Risk factors for SARS-CoV-2 infection at a UK electricity-generating company: a test-negative design case-control study.

OBJECTIVES: Identify workplace risk factors for SARS-CoV-2 infection, using data collected by a UK electricity-generating company. METHODS: Using a test-negative design case-control study, we estimated the OR of infection by job category, site, test reason, sex, vaccination status, vulnerability, site outage and site COVID-19 weekly risk rating, adjusting for age, test date and test type. RESULTS: From an original 80 077 COVID-19 tests, there were 70 646 included in the final analysis. Most exclusions were due to being visitor tests (5030) or tests after an individual first tested positive (2968).Women were less likely to test positive than men (OR=0.71; 95% CI 0.58 to 0.86). Test reason was strongly associated with positivity and although not a cause of infection itself, due to differing test regimes by area, it was a strong confounder for other variables. Compared with routine tests, tests due to symptoms were highest risk (94.99; 78.29 to 115.24), followed by close contact (16.73; 13.80 to 20.29) and broader-defined work contact 2.66 (1.99 to 3.56). After adjustment, we found little difference in risk by job category, but some differences by site with three sites showing substantially lower risks, and one site showing higher risks in the final model. CONCLUSIONS: In general, infection risk was not associated with job category. Vulnerable individuals were at slightly lower risk, tests during outages were higher risk, vaccination showed no evidence of an effect on testing positive, and site COVID-19 risk rating did not show an ordered trend in positivity rates.

Workplace interventions to reduce the risk of SARS-CoV-2 infection outside of healthcare settings.

BACKGROUND: Although many people infected with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) experience no or mild symptoms, some individuals can develop severe illness and may die, particularly older people and those with underlying medical problems. Providing evidence-based interventions to prevent SARS-CoV-2 infection has become more urgent with the potential psychological toll imposed by the coronavirus disease 2019 (COVID-19) pandemic. Controlling exposures to occupational hazards is the fundamental method of protecting workers. When it comes to the transmission of viruses, workplaces should first consider control measures that can potentially have the most significant impact. According to the hierarchy of controls, one should first consider elimination (and substitution), then engineering controls, administrative controls, and lastly, personal protective equipment. This is the first update of a Cochrane review published 6 May 2022, with one new study added. OBJECTIVES: To assess the benefits and harms of interventions in non-healthcare-related workplaces aimed at reducing the risk of SARS-CoV-2 infection compared to other interventions or no intervention. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Web of Science Core Collections, Cochrane COVID-19 Study Register, World Health Organization (WHO) COVID-19 Global literature on coronavirus disease, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform, and medRxiv to 13 April 2023. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and non-randomised studies of interventions. We included adult workers, both those who come into close contact with clients or customers (e.g. public-facing employees, such as cashiers or taxi drivers), and those who do not, but who could be infected by coworkers. We excluded studies involving healthcare workers. We included any intervention to prevent or reduce workers' exposure to SARS-CoV-2 in the workplace, defining categories of intervention according to the hierarchy of hazard controls (i.e. elimination; engineering controls; administrative controls; personal protective equipment). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were incidence rate of SARS-CoV-2 infection (or other respiratory viruses), SARS-CoV-2-related mortality, adverse events, and absenteeism from work. Our secondary outcomes were all-cause mortality, quality of life, hospitalisation, and uptake, acceptability, or adherence to strategies. We used the Cochrane RoB 2 tool to assess risk of bias, and GRADE methods to evaluate the certainty of evidence for each outcome. MAIN RESULTS: We identified 2 studies including a total of 16,014 participants. Elimination-of-exposure interventions We included one study examining an intervention that focused on elimination of hazards, which was an open-label, cluster-randomised, non-inferiority trial, conducted in England in 2021. The study compared standard 10-day self-isolation after contact with an infected person to a new strategy of daily rapid antigen testing and staying at work if the test is negative (test-based attendance). The trialists hypothesised that this would lead to a similar rate of infections, but lower COVID-related absence. Staff (N = 11,798) working at 76 schools were assigned to standard isolation, and staff (N = 12,229) working at 86 schools were assigned to the test-based attendance strategy. The results between test-based attendance and standard 10-day self-isolation were inconclusive for the rate of symptomatic polymerase chain reaction (PCR)-positive SARS-CoV-2 infection (rate ratio (RR) 1.28, 95% confidence interval (CI) 0.74 to 2.21; 1 study; very low-certainty evidence). The results between test-based attendance and standard 10-day self-isolation were inconclusive for the rate of any PCR-positive SARS-CoV-2 infection (RR 1.35, 95% CI 0.82 to 2.21; 1 study; very low-certainty evidence). COVID-related absenteeism rates were 3704 absence days in 566,502 days-at-risk (6.5 per 1000 working days) in the control group and 2932 per 539,805 days-at-risk (5.4 per 1000 working days) in the intervention group (RR 0.83, 95% CI 0.55 to 1.25). We downgraded the certainty of the evidence to low due to imprecision. Uptake of the intervention was 71% in the intervention group, but not reported for the control intervention. The trial did not measure our other outcomes of SARS-CoV-2-related mortality, adverse events, all-cause mortality, quality of life, or hospitalisation. We found seven ongoing studies using elimination-of-hazard strategies, six RCTs and one non-randomised trial. Administrative control interventions We found one ongoing RCT that aims to evaluate the efficacy of the Bacillus Calmette-Guérin (BCG) vaccine in preventing COVID-19 infection and reducing disease severity. Combinations of eligible interventions We included one non-randomised study examining a combination of elimination of hazards, administrative controls, and personal protective equipment. The study was conducted in two large retail companies in Italy in 2020. The study compared a safety operating protocol, measurement of body temperature and oxygen saturation upon entry, and a SARS-CoV-2 test strategy with a minimum activity protocol. Both groups received protective equipment. All employees working at the companies during the study period were included: 1987 in the intervention company and 1798 in the control company. The study did not report an outcome of interest for this systematic review. Other intervention categories We did not find any studies in this category. AUTHORS' CONCLUSIONS: We are uncertain whether a test-based attendance policy affects rates of PCR-positive SARS-CoV-2 infection (any infection; symptomatic infection) compared to standard 10-day self-isolation amongst school and college staff. A test-based attendance policy may result in little to no difference in absenteeism rates compared to standard 10-day self-isolation. The non-randomised study included in our updated search did not report any outcome of interest for this Cochrane review. As a large part of the population is exposed in the case of a pandemic, an apparently small relative effect that would not be worthwhile from the individual perspective may still affect many people, and thus become an important absolute effect from the enterprise or societal perspective. The included RCT did not report on any of our other primary outcomes (i.e. SARS-CoV-2-related mortality and adverse events). We identified no completed studies on any other interventions specified in this review; however, eight eligible studies are ongoing. More controlled studies are needed on testing and isolation strategies, and working from home, as these have important implications for work organisations.

Selective prefrontal-amygdala circuit interactions underlie social and nonsocial valuation in rhesus macaques.

Lesion studies in macaques suggest dissociable functions of the orbitofrontal cortex (OFC) and medial frontal cortex (MFC), with OFC being essential for goal-directed decision making and MFC supporting social cognition. Bilateral amygdala damage results in impairments in both of these domains. There are extensive reciprocal connections between these prefrontal areas and the amygdala; however, it is not known whether the dissociable roles of OFC and MFC depend on functional interactions with the amygdala. To test this possibility, we compared the performance of male rhesus macaques (Macaca mulatta) with crossed surgical disconnection of the amygdala and either MFC (MFC x AMY, n=4) or OFC (OFC x AMY, n=4) to a group of unoperated controls (CON, n=5). All monkeys were assessed for their performance on two tasks to measure: (1) food-retrieval latencies while viewing videos of social and nonsocial stimuli in a test of social interest, and (2) object choices based on current food value using reinforcer devaluation in a test of goal-directed decision making. Compared to the CON group, the MFC x AMY group, but not the OFC x AMY group, showed significantly reduced food-retrieval latencies while viewing videos of conspecifics, indicating reduced social valuation and/or interest. By contrast, on the devaluation task, group OFC x AMY, but not group MFC x AMY, displayed deficits on object choices following changes in food value. These data indicate that the MFC and OFC must functionally interact with the amygdala to support normative social and nonsocial valuation, respectively.Significance StatementAscribing value to conspecifics (social) vs. objects (nonsocial) may be supported by distinct but overlapping brain networks. Here we test whether two nonoverlapping regions of the prefrontal cortex, the medial frontal cortex and the orbitofrontal cortex, must causally interact with the amygdala to sustain social valuation and goal-directed decision making, respectively. We found that these prefrontal-amygdala circuits are functionally dissociable, lending support for the idea that medial frontal and orbital frontal cortex make independent contributions to cognitive appraisals of the environment. These data provide a neural framework for distinct value assignment processes and may enhance our understanding of the cognitive deficits observed following brain injury or in the development of mental health disorders.

Occupational differences in the prevalence and severity of long-COVID: analysis of the Coronavirus (COVID-19) Infection Survey.

OBJECTIVES: To establish whether prevalence and severity of long-COVID symptoms vary by industry and occupation. METHODS: We used Office for National Statistics COVID-19 Infection Survey (CIS) data (February 2021-April 2022) of working-age participants (16-65 years). Exposures were industry, occupation and major Standard Occupational Classification (SOC) group. Outcomes were self-reported: (1) long-COVID symptoms and (2) reduced function due to long-COVID. Binary (outcome 1) and ordered (outcome 2) logistic regression were used to estimate odds ratios (OR)and prevalence (marginal means). RESULTS: Public facing industries, including teaching and education, social care, healthcare, civil service, retail and transport industries and occupations, had the highest likelihood of long-COVID. By major SOC group, those in caring, leisure and other services (OR 1.44, 95% CIs 1.38 to 1.52) had substantially elevated odds than average. For almost all exposures, the pattern of ORs for long-COVID symptoms followed SARS-CoV-2 infections, except for professional occupations (eg, some healthcare, education, scientific occupations) (infection: OR<1 ; long-COVID: OR>1). The probability of reporting long-COVID for industry ranged from 7.7% (financial services) to 11.6% (teaching and education); whereas the prevalence of reduced function by 'a lot' ranged from 17.1% (arts, entertainment and recreation) to 22%-23% (teaching and education and armed forces) and to 27% (not working). CONCLUSIONS: The risk and prevalence of long-COVID differs across industries and occupations. Generally, it appears that likelihood of developing long-COVID symptoms follows likelihood of SARS-CoV-2 infection, except for professional occupations. These findings highlight sectors and occupations where further research is needed to understand the occupational factors resulting in long-COVID.

Potential contribution of vaccination uptake to occupational differences in risk of SARS-CoV-2: analysis of the ONS COVID-19 Infection Survey.

OBJECTIVES: To assess variation in vaccination uptake across occupational groups as a potential explanation for variation in risk of SARS-CoV-2 infection. DESIGN: We analysed data from the UK Office of National Statistics COVID-19 Infection Survey linked to vaccination data from the National Immunisation Management System in England from 1 December 2020 to 11 May 2022. We analysed vaccination uptake and SARS-CoV-2 infection risk by occupational group and assessed whether adjustment for vaccination reduced the variation in risk between occupational groups. RESULTS: Estimated rates of triple vaccination were high across all occupational groups (80% or above), but were lowest for food processing (80%), personal care (82%), hospitality (83%), manual occupations (84%) and retail (85%). High rates were observed for individuals working in health (95% for office based, 92% for those in patient-facing roles) and education (91%) and office-based workers not included in other categories (90%). The impact of adjusting for vaccination when estimating relative risks of infection was generally modest (ratio of hazard ratios across all occupational groups reduced from 1.37 to 1.32), but was consistent with the hypothesis that low vaccination rates contribute to elevated risk in some groups. CONCLUSIONS: Variation in vaccination coverage might account for a modest proportion of occupational differences in infection risk. Vaccination rates were uniformly very high in this cohort, which may suggest that the participants are not representative of the general population. Accordingly, these results should be considered tentative pending the accumulation of additional evidence.

Do Concentration or Activity of Selenoproteins Change in Acute Stroke Patients? A Systematic Review and Meta-Analyses.

INTRODUCTION: Stroke is characterized by deleterious oxidative stress. Selenoprotein enzymes are essential endogenous antioxidants, and detailed insight into their role after stroke could define new therapeutic treatments. This systematic review aimed to elucidate how blood selenoprotein concentration and activity change in the acute phase of stroke. METHODS: We searched PubMed, EMBASE, and Medline databases for studies measuring serial blood selenoprotein concentration or activity in acute stroke patients or in stroke patients compared to non-stroke controls. Meta-analyses of studies stratified by the type of stroke, blood compartment, and type of selenoprotein measurement were conducted. RESULTS: Eighteen studies and data from 941 stroke patients and 708 non-stroke controls were included in this review. Glutathione peroxidase (GPx) was the only identified selenoprotein, and its activity was most frequently measured. Results from 12 studies and 693 patients showed that compared to non-stroke controls in acute ischaemic stroke patients, the GPx activity increased in haemolysate (standardized mean difference [SMD]: 0.27, 95% CI: 0.07-0.47) but decreased in plasma (mean difference [MD]: -1.08 U/L, 95% CI: -1.94 to -0.22) and serum (SMD: -0.54, 95% CI: -0.91 to -0.17). From 4 identified studies in 106 acute haemorrhagic stroke patients, the GPx activity decreased in haemolysate (SMD: -0.40, 95% CI: -0.68 to -0.13) and remained unchanged in plasma (MD: -0.10 U/L, 95% CI: -0.81 to 0.61) and serum (MD: -5.00 U/mL, 95% CI: -36.17 to 26.17) compared to non-stroke controls. Results from studies assessing the GPx activity in the haemolysate compartment were inconsistent and characterized by high heterogeneity. CONCLUSIONS: Our results suggest a reduction of the blood GPx activity in acute ischaemic stroke patients, a lack of evidence regarding a role for GPx in haemorrhagic stroke patients, and insufficient evidence for other selenoproteins.

Occupation and COVID-19 mortality in England: a national linked data study of 14.3 million adults.

OBJECTIVES: To estimate occupational differences in COVID-19 mortality and test whether these are confounded by factors such as regional differences, ethnicity and education or due to non-workplace factors, such as deprivation or prepandemic health. METHODS: Using a cohort study of over 14 million people aged 40-64 years living in England, we analysed occupational differences in death involving COVID-19, assessed between 24 January 2020 and 28 December 2020.We estimated age-standardised mortality rates (ASMRs) per 100 000 person-years at risk stratified by sex and occupation. We estimated the effect of occupation on COVID-19 mortality using Cox proportional hazard models adjusted for confounding factors. We further adjusted for non-workplace factors and interpreted the residual effects of occupation as being due to workplace exposures to SARS-CoV-2. RESULTS: In men, the ASMRs were highest among those working as taxi and cab drivers or chauffeurs at 119.7 deaths per 100 000 (95% CI 98.0 to 141.4), followed by other elementary occupations at 106.5 (84.5 to 132.4) and care workers and home carers at 99.2 (74.5 to 129.4). Adjusting for confounding factors strongly attenuated the HRs for many occupations, but many remained at elevated risk. Adjusting for living conditions reduced further the HRs, and many occupations were no longer at excess risk. For most occupations, confounding factors and mediators other than workplace exposure to SARS-CoV-2 explained 70%-80% of the excess age-adjusted occupational differences. CONCLUSIONS: Working conditions play a role in COVID-19 mortality, particularly in occupations involving contact with patients or the public. However, there is also a substantial contribution from non-workplace factors.

Workplace interventions to reduce the risk of SARS-CoV-2 infection outside of healthcare settings.

BACKGROUND: Although many people infected with SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) experience no or mild symptoms, some individuals can develop severe illness and may die, particularly older people and those with underlying medical problems. Providing evidence-based interventions to prevent SARS-CoV-2 infection has become more urgent with the spread of more infectious SARS-CoV-2 variants of concern (VoC), and the potential psychological toll imposed by the coronavirus disease 2019 (COVID-19) pandemic.   Controlling exposures to occupational hazards is the fundamental method of protecting workers. When it comes to the transmission of viruses, such as SARS-CoV-2, workplaces should first consider control measures that can potentially have the most significant impact. According to the hierarchy of controls, one should first consider elimination (and substitution), then engineering controls, administrative controls, and lastly, personal protective equipment (PPE). OBJECTIVES: To assess the benefits and harms of interventions in non-healthcare-related workplaces to reduce the risk of SARS-CoV-2 infection relative to other interventions, or no intervention. SEARCH METHODS: We searched MEDLINE, Embase, Web of Science, Cochrane COVID-19 Study Register, the Canadian Centre for Occupational Health and Safety (CCOHS), Clinicaltrials.gov, and the International Clinical Trials Registry Platform to 14 September 2021. We will conduct an update of this review in six months. SELECTION CRITERIA: We included randomised control trials (RCT) and planned to include non-randomised studies of interventions. We included adult workers, both those who come into close contact with clients or customers (e.g. public-facing employees, such as cashiers or taxi drivers), and those who do not, but who could be infected by co-workers. We excluded studies involving healthcare workers. We included any intervention to prevent or reduce workers' exposure to SARS-CoV-2 in the workplace, defining categories of intervention according to the hierarchy of hazard controls, i.e. elimination; engineering controls; administrative controls; personal protective equipment. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were incidence rate of SARS-CoV-2 infection (or other respiratory viruses), SARS-CoV-2-related mortality, adverse events, and absenteeism from work. Our secondary outcomes were all-cause mortality, quality of life, hospitalisation, and uptake, acceptability, or adherence to strategies. We used the Cochrane RoB 2 tool to assess the risk of bias, and GRADE methods to assess the certainty of evidence for each outcome. MAIN RESULTS: Elimination of exposure interventions We included one study examining an intervention that focused on elimination of hazards. This study is an open-label, cluster-randomised, non-inferiority trial, conducted in England in 2021. The study compared standard 10-day self-isolation after contact with an infected person to a new strategy of daily rapid antigen testing and staying at work if the test is negative (test-based attendance). The trialists hypothesised that this would lead to a similar rate of infections, but lower COVID-related absence. Staff (N = 11,798) working at 76 schools were assigned to standard isolation, and staff (N = 12,229) at 86 schools to the test-based attendance strategy.  The results between test-based attendance and standard 10-day self-isolation were inconclusive for the rate of symptomatic PCR-positive SARS-COV-2 infection rate ratio ((RR) 1.28, 95% confidence interval (CI) 0.74 to 2.21; 1 study, very low-certainty evidence)). The results between test-based attendance and standard 10-day self-isolation were inconclusive for the rate of any PCR-positive SARS-COV-2 infection (RR 1.35, 95% CI 0.82 to 2.21; 1 study, very low-certainty evidence). COVID-related absenteeism rates were 3704 absence days in 566,502 days-at-risk (6.5 per 1000 days at risk) in the control group and 2932 per 539,805 days-at-risk (5.4 per 1000 days at risk) in the intervention group (RR 0.83; 95% CI 0.55 to 1.25). The certainty of the evidence was downgraded to low, due to imprecision. Uptake of the intervention was 71 % in the intervention group, but not reported for the control intervention.  The trial did not measure other outcomes, SARS-CoV-2-related mortality, adverse events, all-cause mortality, quality of life, and hospitalisation. We found one ongoing RCT about screening in schools, using elimination of hazard strategies. Personal protective equipment We found one ongoing non-randomised study on the effects of closed face shields to prevent COVID-19 transmission. Other intervention categories We did not find studies in the other intervention categories. AUTHORS' CONCLUSIONS: We are uncertain whether a test-based attendance policy affects rates of PCR-postive SARS-CoV-2 infection (any infection; symptomatic infection) compared to standard 10-day self-isolation amongst school and college staff. Test-based attendance policy may result in little to no difference in absence rates compared to standard 10-day self-isolation. As a large part of the population is exposed in the case of a pandemic, an apparently small relative effect that would not be worthwhile from the individual perspective may still affect many people, and thus, become an important absolute effect from the enterprise or societal perspective.  The included study did not report on any other primary outcomes of our review, i.e. SARS-CoV-2-related mortality and adverse events. No completed studies were identified on any other interventions specified in this review, but two eligible studies are ongoing. More controlled studies are needed on testing and isolation strategies, and working from home, as these have important implications for work organisations.

Transmission of Antimicrobial-Resistant Staphylococcus aureus Clonal Complex 9 between Pigs and Humans, United States.

Transmission of livestock-associated Staphylococcus aureus clonal complex 9 (LA-SA CC9) between pigs raised on industrial hog operations (IHOs) and humans in the United States is poorly understood. We analyzed whole-genome sequences from 32 international S. aureus CC9 isolates and 49 LA-SA CC9 isolates from IHO pigs and humans who work on or live near IHOs in 10 pig-producing counties in North Carolina, USA. Bioinformatic analysis of sequence data from the 81 isolates demonstrated 3 major LA-SA CC9 clades. North Carolina isolates all fell within a single clade (C3). High-resolution phylogenetic analysis of C3 revealed 2 subclades of intermingled IHO pig and human isolates differing by 0-34 single-nucleotide polymorphisms. Our findings suggest that LA-SA CC9 from pigs and humans share a common source and provide evidence of transmission of antimicrobial-resistant LA-SA CC9 between IHO pigs and humans who work on or live near IHOs in North Carolina.

Getting ahead of antibiotic-resistant Staphylococcus aureus in U.S. hogs.

Antibiotic-resistant strains of Staphylococcus aureus, an opportunistic bacterial pathogen, have emerged in industrial livestock operations and agricultural settings. In the United States, there is limited access to industrial livestock operations and farm-level antibiotic use data. As a result, studies often rely on retail meat as a proxy for direct animal sampling. To move beyond this limitation and assess S. aureus colonization in hogs, we purchased the heads of recently-slaughtered hogs and compared S. aureus populations in those raised on industrial hog operations versus those raised without antibiotics. S. aureus isolates were analyzed for antibiotic resistance and putative genotypic markers of livestock adaptation. Although methicillin-resistant S. aureus (MRSA) was not detected in this study, all of the hogs from industrial hog operations (n = 9/9) carried multidrug-resistant S. aureus (MDRSA) with two livestock-adaptation markers (scn-negative and clonal complex (CC) 9 or 398) compared to 11% of hogs raised without antibiotics (n = 1/9). Hogs from industrial operations were 9.0 times (95% confidence interval (CI): 1.4-57.1) as likely to carry livestock-adapted S. aureus and 4.5 times (95% CI: 1.3-15.3) as likely to carry MDRSA as hogs raised without antibiotics. In contrast, the majority of antibiotic-free hogs (67%, n = 6/9) contained human-adapted S. aureus (i.e. scn-positive, CC1) compared to 11% (n = 1/9) of IHO hogs. These results indicate that antibiotic use in IHO hogs may make them more conducive hosts to antibiotic-resistant, livestock-adapted S. aureus strains when compared to hogs raised without antibiotics. Our results are important, as they provide strong evidence that antibiotic use practices influence the S. aureus populations carried by U.S. hogs, supporting the need for increased access to routine monitoring of hog operations for antibiotic resistance management using a One Health framework.

Alternative reactive support surfaces (non-foam and non-air-filled) for preventing pressure ulcers.

BACKGROUND: Pressure ulcers (also known as injuries, pressure sores, decubitus ulcers and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Reactive surfaces that are not made of foam or air cells can be used for preventing pressure ulcers. OBJECTIVES: To assess the effects of non-foam and non-air-filled reactive beds, mattresses or overlays compared with any other support surface on the incidence of pressure ulcers in any population in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to non-foam or non-air-filled reactive beds, overlays or mattresses. Comparators were any beds, overlays or mattresses used. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. If a non-foam or non-air-filled surface was compared with surfaces that were not clearly specified, then the included study was recorded and described but not considered further in any data analyses. MAIN RESULTS: We included 20 studies (4653 participants) in this review. Most studies were small (median study sample size: 198 participants). The average participant age ranged from 37.2 to 85.4 years (median: 72.5 years). Participants were recruited from a wide range of care settings but were mainly from acute care settings. Almost all studies were conducted in Europe and America. Of the 20 studies, 11 (2826 participants) included surfaces that were not well described and therefore could not be fully classified. We synthesised data for the following 12 comparisons: (1) reactive water surfaces versus alternating pressure (active) air surfaces (three studies with 414 participants), (2) reactive water surfaces versus foam surfaces (one study with 117 participants), (3) reactive water surfaces versus reactive air surfaces (one study with 37 participants), (4) reactive water surfaces versus reactive fibre surfaces (one study with 87 participants), (5) reactive fibre surfaces versus alternating pressure (active) air surfaces (four studies with 384 participants), (6) reactive fibre surfaces versus foam surfaces (two studies with 228 participants), (7) reactive gel surfaces on operating tables followed by foam surfaces on ward beds versus alternating pressure (active) air surfaces on operating tables and subsequently on ward beds (two studies with 415 participants), (8) reactive gel surfaces versus reactive air surfaces (one study with 74 participants), (9) reactive gel surfaces versus foam surfaces (one study with 135 participants), (10) reactive gel surfaces versus reactive gel surfaces (one study with 113 participants), (11) reactive foam and gel surfaces versus reactive gel surfaces (one study with 166 participants) and (12) reactive foam and gel surfaces versus foam surfaces (one study with 91 participants). Of the 20 studies, 16 (80%) presented findings which were considered to be at high overall risk of bias. PRIMARY OUTCOME: Pressure ulcer incidence We did not find analysable data for two comparisons: reactive water surfaces versus foam surfaces, and reactive water surfaces versus reactive fibre surfaces. Reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds (14/205 (6.8%)) may increase the proportion of people developing a new pressure ulcer compared with alternating pressure (active) air surfaces applied on both operating tables and hospital beds (3/210 (1.4%) (risk ratio 4.53, 95% confidence interval 1.31 to 15.65; 2 studies, 415 participants; I2 = 0%; low-certainty evidence). For all other comparisons, it is uncertain whether there is a difference in the proportion of participants developing new pressure ulcers as all data were of very low certainty. Included studies did not report time to pressure ulcer incidence for any comparison in this review. Secondary outcomes Support-surface-associated patient comfort: the included studies provide data on this outcome for one comparison. It is uncertain if there is a difference in patient comfort between alternating pressure (active) air surfaces and reactive fibre surfaces (one study with 187 participants; very low-certainty evidence). All reported adverse events: there is evidence on this outcome for one comparison. It is uncertain if there is a difference in adverse events between reactive gel surfaces followed by foam surfaces and alternating pressure (active) air surfaces applied on both operating tables and hospital beds (one study with 198 participants; very low-certainty evidence). We did not find any health-related quality of life or cost-effectiveness evidence for any comparison in this review. AUTHORS' CONCLUSIONS: Current evidence is generally uncertain about the differences between non-foam and non-air-filled reactive surfaces and other surfaces in terms of pressure ulcer incidence, patient comfort, adverse effects, health-related quality of life and cost-effectiveness. Reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds may increase the risk of having new pressure ulcers compared with alternating pressure (active) air surfaces applied on both operating tables and hospital beds. Future research in this area should consider evaluation of the most important support surfaces from the perspective of decision-makers. Time-to-event outcomes, careful assessment of adverse events and trial-level cost-effectiveness evaluation should be considered in future studies. Trials should be designed to minimise the risk of detection bias; for example, by using digital photography and adjudicators of the photographs being blinded to group allocation. Further review using network meta-analysis will add to the findings reported here.

ANTECEDENTES: Las úlceras por presión (también conocidas como úlceras y escaras de decúbito) son lesiones localizadas en la piel o en los tejidos blandos subyacentes, o en ambos, causadas por la presión, el cizallamiento o la fricción no aliviados. Las superficies estáticas que no son de espuma o celdas de aire se pueden utilizar para prevenir las úlceras por presión. OBJETIVOS: Evaluar los efectos de las camas, los colchones o los sobrecolchones estáticos sin espuma y sin aire en comparación con cualquier otra superficie especial para el manejo de la presión (SEMP) o sobre la incidencia de las úlceras por presión en cualquier población y en cualquier contexto. MÉTODOS DE BÚSQUEDA: En noviembre de 2019 se hicieron búsquedas en el Registro especializado del Grupo Cochrane de Heridas (Cochrane Wounds), en el Registro Cochrane central de ensayos controlados (Cochrane Central Register of Controlled Trials, CENTRAL); Ovid MEDLINE (incluido In­Process & Other Non­Indexed Citations); Ovid Embase y EBSCO CINAHL Plus. También se buscaron estudios en curso y no publicados en los registros de ensayos clínicos, y se examinaron las listas de referencias de los estudios incluidos pertinentes, así como de las revisiones, los metanálisis y los informes de tecnología sanitaria para identificar estudios adicionales. No hubo restricciones en cuanto al idioma, la fecha de publicación ni el contexto de los estudios. CRITERIOS DE SELECCIÓN: Se incluyeron los ensayos controlados aleatorizados que asignaron a participantes de cualquier edad a camas, colchones o sobrecolchones estáticos sin espuma y sin aire. Los comparadores fueron todas las camas, sobrecolchones o colchones utilizados. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Al menos dos autores de la revisión evaluaron de forma independiente los ensayos según criterios de inclusión predeterminados. Se realizó la extracción de los datos, la evaluación del riesgo de sesgo mediante la herramienta Cochrane "Risk of bias" y la evaluación de la certeza de la evidencia según el método Grading of Recommendations, Assessment, Development and Evaluations. Si se comparaba una superficie sin espuma o sin aire con superficies que no estaban claramente especificadas, se registraba y describía el estudio incluido, pero no se tenía en cuenta en ningún análisis de datos. RESULTADOS PRINCIPALES: En esta revisión se incluyeron 20 estudios (4653 participantes). La mayoría de los estudios eran pequeños (mediana del tamaño muestral de los estudios: 198 participantes). La edad promedio de los participantes varió entre 37,2 y 85,4 años (mediana: 72,5 años). Los participantes se reclutaron en una amplia variedad de ámbitos asistenciales, pero principalmente en ámbitos de cuidados intensivos y de agudos. Casi todos los estudios se realizaron en Europa y América. De los 20 estudios, 11 (2826 participantes) incluían superficies que no estaban bien descritas y, por lo tanto, no se podían clasificar completamente. Se resumieron los datos de las 12 comparaciones siguientes: (1) superficies de agua estáticas versus superficies de aire de presión alternante (activas) (tres estudios con 414 participantes), (2) superficies de agua estáticas versus superficies de espuma (un estudio con 117 participantes), (3) superficies de agua estáticas versus superficies de aire estáticas (un estudio con 37 participantes), (4) superficies de agua estáticas versus superficies de fibras estáticas (un estudio con 87 participantes), (5) superficies de fibras estáticas versus superficies de aire de presión alternante (activas) (cuatro estudios con 384 participantes), (6) superficies de fibras estáticas versus superficies de espuma (dos estudios con 228 participantes), (7) superficies de gel estáticas en las mesas de operaciones, seguidas de superficies de espuma en las camas de las salas, versus superficies de aire de presión alternante (activas) en las mesas de operaciones y posteriormente en las camas de las salas (dos estudios con 415 participantes), (8) superficies de gel estáticas versus superficies de aire estáticas (un estudio con 74 participantes) (9) superficies de gel estáticas versus superficies de espuma (un estudio con 135 participantes), (10) superficies de gel estáticas versus superficies de gel estáticas (un estudio con 113 participantes), (11) superficies de espuma y gel estáticas versus superficies de gel estáticas (un estudio con 166 participantes) y (12) superficies de espuma y gel estáticas versus superficies de espuma (un estudio con 91 participantes). De los 20 estudios, 16 (80%) presentaron resultados que se consideraron con alto riesgo general de sesgo. Desenlace principal: incidencia de las úlceras por presión No se encontraron datos analizables para dos comparaciones: superficies de agua estáticas versus superficies de espuma, ni superficies de agua estáticas versus superficies de fibras estáticas. Las superficies de gel estáticas utilizadas en las mesas de operaciones seguidas de las superficies de espuma aplicadas en las camas de hospital (14/205 [6,8%]) podrían aumentar la proporción de personas que presentan una nueva úlcera por presión en comparación con las superficies de aire de presión alternante (activas) aplicadas en las mesas de operaciones y en las camas de hospital (3/210 [1,4%]) (razón de riesgos 4,53; intervalo de confianza del 95%: 1,31 a 15,65; dos estudios, 415 participantes; I2 = 0%; evidencia de certeza baja). Para todas las demás comparaciones, no hay certeza de que haya una diferencia en la proporción de participantes que presentan nuevas úlceras por presión, ya que todos los datos eran de certeza muy baja. Los estudios incluidos no informaron el tiempo hasta la incidencia de las úlceras por presión para ninguna comparación en esta revisión. Desenlaces secundarios Comodidad del paciente asociada con la SEMP: los estudios incluidos proporcionan datos sobre este desenlace para una comparación. No está claro si existe una diferencia en la comodidad del paciente entre las superficies de aire de presión alternante (activas) y las superficies de fibras estáticas (un estudio con 187 participantes; evidencia de certeza muy baja). Todos los eventos adversos informados: hay evidencia sobre este desenlace para una comparación. No se sabe si existe una diferencia en los eventos adversos entre las superficies de gel estáticas seguidas de superficies de espuma y las superficies de aire de presión alternante (activas) aplicadas tanto en las mesas de operaciones como en las camas de hospital (un estudio con 198 participantes; evidencia de certeza muy baja). No se encontró evidencia acerca de la calidad de vida relacionada con la salud ni de la coste­efectividad para ninguna comparación en esta revisión. CONCLUSIONES DE LOS AUTORES: Por lo general no se desconoce la evidencia actual sobre las diferencias entre las superficies estáticas sin espuma y sin aire y otras superficies en términos de la incidencia de las úlceras por presión, la comodidad del paciente, los efectos adversos, la calidad de vida relacionada con la salud y la coste­efectividad. Las superficies de gel estáticas utilizadas en las mesas de operaciones, seguidas de las superficies de espuma aplicadas en las camas de hospital, podrían aumentar el riesgo de aparición de nuevas úlceras por presión en comparación con las superficies de aire de presión alternante (activas) aplicadas en las mesas de operaciones y en las camas de hospital. Los estudios de investigación futuros en este campo deberían considerar la evaluación de las SEMP más importantes desde la perspectiva de aquellos que toman decisiones. En los estudios futuros se deben considerar los desenlaces de tiempo hasta el evento, la evaluación cuidadosa de los eventos adversos y la evaluación de la coste­efectividad a nivel de ensayo. Los ensayos deben estar diseñados para minimizar el riesgo de sesgo de detección; por ejemplo, con el uso de fotografía digital y el cegamiento de los adjudicatarios de las fotografías a la asignación a los grupos. Una revisión posterior mediante metanálisis en red ampliará los resultados aquí proporcionados.

Foam surfaces for preventing pressure ulcers.

BACKGROUND: Pressure ulcers (also known as pressure injuries) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Foam surfaces (beds, mattresses or overlays) are widely used with the aim of preventing pressure ulcers. OBJECTIVES: To assess the effects of foam beds, mattresses or overlays compared with any support surface on the incidence of pressure ulcers in any population in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to foam beds, mattresses or overlays. Comparators were any beds, mattresses or overlays. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. If a foam surface was compared with surfaces that were not clearly specified, then the included study was recorded and described but not considered further in any data analyses. MAIN RESULTS: We included 29 studies (9566 participants) in the review. Most studies were small (median study sample size: 101 participants). The average age of participants ranged from 47.0 to 85.3 years (median: 76.0 years). Participants were mainly from acute care settings. We analysed data for seven comparisons in the review: foam surfaces compared with: (1) alternating pressure air surfaces, (2) reactive air surfaces, (3) reactive fibre surfaces, (4) reactive gel surfaces, (5) reactive foam and gel surfaces, (6) reactive water surfaces, and (7) another type of foam surface. Of the 29 included studies, 17 (58.6%) presented findings which were considered at high overall risk of bias. PRIMARY OUTCOME: pressure ulcer incidence Low-certainty evidence suggests that foam surfaces may increase the risk of developing new pressure ulcers compared with (1) alternating pressure (active) air surfaces (risk ratio (RR) 1.59, 95% confidence interval (CI) 0.86 to 2.95; I2 = 63%; 4 studies, 2247 participants), and (2) reactive air surfaces (RR 2.40, 95% CI 1.04 to 5.54; I2 = 25%; 4 studies, 229 participants). We are uncertain regarding the difference in pressure ulcer incidence in people treated with foam surfaces and the following surfaces: (1) reactive fibre surfaces (1 study, 68 participants); (2) reactive gel surfaces (1 study, 135 participants); (3) reactive gel and foam surfaces (1 study, 91 participants); and (4) another type of foam surface (6 studies, 733 participants). These had very low-certainty evidence. Included studies have data on time to pressure ulcer development for two comparisons. When time to ulcer development is considered using hazard ratios, the difference in the risk of having new pressure ulcers, over 90 days' follow-up, between foam surfaces and alternating pressure air surfaces is uncertain (2 studies, 2105 participants; very low-certainty evidence). Two further studies comparing different types of foam surfaces also reported time-to-event data, suggesting that viscoelastic foam surfaces with a density of 40 to 60 kg/m3 may decrease the risk of having new pressure ulcers over 11.5 days' follow-up compared with foam surfaces with a density of 33 kg/m3 (1 study, 62 participants); and solid foam surfaces may decrease the risk of having new pressure ulcers over one month's follow-up compared with convoluted foam surfaces (1 study, 84 participants). Both had low-certainty evidence. There was no analysable data for the comparison of foam surfaces with reactive water surfaces (one study with 117 participants). Secondary outcomes Support-surface-associated patient comfort: the review contains data for three comparisons for this outcome. It is uncertain if there is a difference in patient comfort measure between foam surfaces and alternating pressure air surfaces (1 study, 76 participants; very low-certainty evidence); foam surfaces and reactive air surfaces (1 study, 72 participants; very low-certainty evidence); and different types of foam surfaces (4 studies, 669 participants; very low-certainty evidence). All reported adverse events: the review contains data for two comparisons for this outcome. We are uncertain about differences in adverse effects between foam surfaces and alternating pressure (active) air surfaces (3 studies, 2181 participants; very low-certainty evidence), and between foam surfaces and reactive air surfaces (1 study, 72 participants; very low-certainty evidence). Health-related quality of life: only one study reported data on this outcome. It is uncertain if there is a difference (low-certainty evidence) between foam surfaces and alternating pressure (active) air surfaces in health-related quality of life measured with two different questionnaires, the EQ-5D-5L (267 participants) and the PU-QoL-UI (233 participants). Cost-effectiveness: one study reported trial-based cost-effectiveness evaluations. Alternating pressure (active) air surfaces are probably more cost-effective than foam surfaces in preventing pressure ulcer incidence (2029 participants; moderate-certainty evidence). AUTHORS' CONCLUSIONS: Current evidence suggests uncertainty about the differences in pressure ulcer incidence, patient comfort, adverse events and health-related quality of life between using foam surfaces and other surfaces (reactive fibre surfaces, reactive gel surfaces, reactive foam and gel surfaces, or reactive water surfaces). Foam surfaces may increase pressure ulcer incidence compared with alternating pressure (active) air surfaces and reactive air surfaces. Alternating pressure (active) air surfaces are probably more cost-effective than foam surfaces in preventing new pressure ulcers. Future research in this area should consider evaluation of the most important support surfaces from the perspective of decision-makers. Time-to-event outcomes, careful assessment of adverse events and trial-level cost-effectiveness evaluation should be considered in future studies. Trials should be designed to minimise the risk of detection bias; for example, by using digital photography and by blinding adjudicators of the photographs to group allocation. Further review using network meta-analysis will add to the findings reported here.

ANTECEDENTES: Las úlceras por presión (también conocidas como úlceras de decúbito) son lesiones localizadas en la piel o en los tejidos blandos subyacentes, o en ambos, y causadas por la presión, el cizallamiento o la fricción no aliviados. Las superficies de espuma (camas, colchones o sobrecolchones) se utilizan ampliamente con el objetivo de prevenir las úlceras por presión. OBJETIVOS: Evaluar los efectos de las camas, los colchones o los sobrecolchones de espuma en comparación con cualquier superficie especial de manejo de presión (SEMP) sobre la incidencia de las úlceras por presión en cualquier población y en cualquier ámbito. MÉTODOS DE BÚSQUEDA: En noviembre de 2019 se realizaron búsquedas en el Registro especializado del Grupo Cochrane de Heridas (Cochrane Wounds); en el Registro Cochrane central de ensayos controlados (Cochrane Central Register of Controlled Trials; CENTRAL); en Ovid MEDLINE (incluido In­Process & Other Non­Indexed Citations); en Ovid Embase y en EBSCO CINAHL Plus. También se buscaron estudios en curso y no publicados en los registros de ensayos clínicos, y se examinaron las listas de referencias de los estudios incluidos pertinentes, así como de las revisiones, los metanálisis y los informes de tecnología sanitaria para identificar estudios adicionales. No hubo restricciones en cuanto al idioma, la fecha de publicación ni el contexto de los estudios. CRITERIOS DE SELECCIÓN: Se incluyeron los ensayos controlados aleatorizados que asignaron a participantes de cualquier edad a camas, colchones o sobrecolchones de espuma. Los comparadores fueron cualquier cama, colchón o sobrecolchón. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Al menos dos autores de la revisión evaluaron de forma independiente los ensayos según los criterios de inclusión predeterminados. Se realizó la extracción de los datos, la evaluación del "riesgo de sesgo" mediante la herramienta Cochrane "Risk of bias" y la evaluación de la certeza de la evidencia según el método Grading of Recommendations, Assessment, Development and Evaluations. Si se comparaba una superficie de espuma con superficies que no estaban claramente especificadas, se registraba y describía el estudio incluido, pero no se tenía en cuenta en ningún análisis de datos. RESULTADOS PRINCIPALES: En la revisión se incluyeron 29 estudios (9566 participantes). La mayoría de los estudios eran pequeños (mediana del tamaño muestral de los estudios: 101 participantes). El promedio de edad de los participantes varió entre 47,0 y 85,3 años (mediana: 76,0 años). Los participantes procedían principalmente de ámbitos de cuidados intensivos y de agudos. En la revisión se analizaron los datos de siete comparaciones: superficies de espuma comparadas con: (1) superficies de aire de presión alternante, (2) superficies de aire estáticas, (3) superficies de fibra estáticas, (4) superficies de gel estáticas, (5) superficies de espuma y gel estáticas, (6) superficies de agua estáticas y (7) otro tipo de superficie de espuma. De los 29 estudios incluidos, 17 (58,6%) presentaron resultados que se consideraron con alto riesgo general de sesgo. Desenlace principal: incidencia de úlceras por presión Evidencia de certeza baja indica que las superficies de espuma podrían aumentar el riesgo de desarrollar nuevas úlceras por presión en comparación con (1) las superficies de aire de presión alternante (activas) (razón de riesgos [RR] 1,59; intervalo de confianza [IC] del 95%: 0,86 a 2,95; I2 = 63%; cuatro estudios, 2247 participantes) y (2) las superficies de aire estáticas (RR 2,40; IC del 95%: 1,04 a 5,54; I2 = 25%; cuatro estudios, 229 participantes). No hay certeza acerca de la diferencia en la incidencia de las úlceras por presión en las personas tratadas con superficies de espuma y las siguientes superficies: (1) superficies de fibras estáticas (un estudio, 68 participantes); (2) superficies de gel estáticas (un estudio, 135 participantes); (3) superficies estáticas de gel y espuma (un estudio, 91 participantes); y (4) otro tipo de superficies de espuma (seis estudios, 733 participantes). Al respecto se cuenta con evidencia de certeza muy baja. Los estudios incluidos cuentan con datos sobre el tiempo hasta la aparición de úlceras por presión para dos comparaciones. Cuando se considera el tiempo hasta la aparición de la úlcera con el uso de los cocientes de riesgos instantáneos, no está clara la diferencia en el riesgo de tener nuevas úlceras por presión, durante 90 días de seguimiento, entre las superficies de espuma y las de aire de presión alternante (dos estudios, 2105 participantes; evidencia de certeza muy baja). Otros dos estudios que compararon diferentes tipos de superficies de espuma también proporcionaron datos sobre el tiempo hasta el evento, e indicaron que las superficies de espuma viscoelástica con una densidad de 40 a 60 kg/m3 podrían disminuir el riesgo de presentar nuevas úlceras por presión durante 11,5 días de seguimiento en comparación con las superficies de espuma con una densidad de 33 kg/m3 (un estudio, 62 participantes) y las superficies de espuma sólida podrían disminuir el riesgo de presentar nuevas úlceras por presión durante un mes de seguimiento en comparación con las superficies de espuma alveolar (un estudio, 84 participantes). Ambos con evidencia de certeza baja. No hubo datos que se pudieran analizar para la comparación de las superficies de espuma con las de agua estáticas (un estudio con 117 participantes). Desenlaces secundarios Comodidad del paciente asociada con la SEMP: la revisión contiene datos de tres comparaciones para este desenlace. No se sabe si existe una diferencia en la medida de comodidad del paciente entre las superficies de espuma y las superficies de aire de presión alternante (un estudio, 76 participantes; evidencia de certeza muy baja); las superficies de espuma y las superficies de aire estáticas (un estudio, 72 participantes; evidencia de certeza muy baja); y los diferentes tipos de superficies de espuma (cuatro estudios, 669 participantes; evidencia de certeza muy baja). Todos los eventos adversos informados: la revisión contiene datos de dos comparaciones para este desenlace. No están claras las diferencias en los efectos adversos entre las superficies de espuma y las superficies de aire de presión alternante (activas) (tres estudios, 2181 participantes; evidencia de certeza muy baja), ni entre las superficies de espuma y las superficies de aire estáticas (un estudio, 72 participantes; evidencia de certeza muy baja). Calidad de vida relacionada con la salud: sólo un estudio proporcionó datos sobre este desenlace. No se sabe si existe una diferencia (evidencia de certeza baja) entre las superficies de espuma y las superficies de aire de presión alternante (activas) en la calidad de vida relacionada con la salud medida con dos cuestionarios diferentes, el EQ­5D­5L (267 participantes) y el PU­QoL­UI (233 participantes). Coste­efectividad: un estudio proporcionó evaluaciones de coste­efectividad a nivel de ensayo. Las superficies de aire de presión alternante (activas) son probablemente más coste­efectivas que las superficies de espuma en la prevención de la incidencia de las úlceras por presión (2029 participantes; evidencia de certeza moderada). CONCLUSIONES DE LOS AUTORES: La evidencia actual indica que no hay certeza acerca de las diferencias en la incidencia de las úlceras por presión, la comodidad del paciente, los eventos adversos ni la calidad de vida relacionada con la salud entre el uso de superficies de espuma y otras SEMP (superficies de fibras estáticas, superficies de gel estáticas, superficies de espuma y gel estáticas o superficies de agua estáticas). Las superficies de espuma podrían aumentar la incidencia de las úlceras por presión en comparación con las superficies de aire de presión alternante (activas) y las superficies de aire estáticas. Las superficies de aire de presión alternante (activas) son probablemente más coste­efectivas que las superficies de espuma para prevenir nuevas úlceras por presión. Los estudios de investigación futuros en este campo deberían considerar la evaluación de las SEMP más importantes desde la perspectiva de los responsables de la toma de decisiones. En los estudios futuros se deben considerar los desenlaces de tiempo hasta el evento, la evaluación cuidadosa de los eventos adversos y la evaluación de la coste­efectividad a nivel de ensayo. Los ensayos deben estar diseñados para minimizar el riesgo de sesgo de detección; por ejemplo, con el uso de fotografía digital y el cegamiento de los adjudicatarios de las fotografías a la asignación a los grupos. Una revisión posterior mediante metanálisis en red ampliará los resultados aquí proporcionados.

Beds, overlays and mattresses for preventing and treating pressure ulcers: an overview of Cochrane Reviews and network meta-analysis.

BACKGROUND: Pressure ulcers (also known as pressure injuries, pressure sores and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Specific kinds of beds, overlays and mattresses are widely used with the aim of preventing and treating pressure ulcers. OBJECTIVES: To summarise evidence from Cochrane Reviews that assess the effects of beds, overlays and mattresses on reducing the incidence of pressure ulcers and on increasing pressure ulcer healing in any setting and population. To assess the relative effects of different types of beds, overlays and mattresses for reducing the incidence of pressure ulcers and increasing pressure ulcer healing in any setting and population. To cumulatively rank the different treatment options of beds, overlays and mattresses in order of their effectiveness in pressure ulcer prevention and treatment. METHODS: In July 2020, we searched the Cochrane Library. Cochrane Reviews reporting the effectiveness of beds, mattresses or overlays for preventing or treating pressure ulcers were eligible for inclusion in this overview. Two review authors independently screened search results and undertook data extraction and risk of bias assessment using the ROBIS tool. We summarised the reported evidence in an overview of reviews. Where possible, we included the randomised controlled trials from each included review in network meta-analyses. We assessed the relative effectiveness of beds, overlays and mattresses for preventing or treating pressure ulcers and their probabilities of being, comparably, the most effective treatment. We assessed the certainty of the evidence using the GRADE approach. MAIN RESULTS: We include six Cochrane Reviews in this overview of reviews, all at low or unclear risk of bias. Pressure ulcer prevention: four reviews (of 68 studies with 18,174 participants) report direct evidence for 27 pairwise comparisons between 12 types of support surface on the following outcomes: pressure ulcer incidence, time to pressure ulcer incidence, patient comfort response, adverse event rates, health-related quality of life, and cost-effectiveness. Here we focus on outcomes with some evidence at a minimum of low certainty. (1) Pressure ulcer incidence: our overview includes direct evidence for 27 comparisons that mostly (19/27) have very low-certainty evidence concerning reduction of pressure ulcer risk. We included 40 studies (12,517 participants; 1298 participants with new ulcers) in a network meta-analysis involving 13 types of intervention. Data informing the network are sparse and this, together with the high risk of bias in most studies informing the network, means most network contrasts (64/78) yield evidence of very low certainty. There is low-certainty evidence that, compared with foam surfaces (reference treatment), reactive air surfaces (e.g. static air overlays) (risk ratio (RR) 0.46, 95% confidence interval (CI) 0.29 to 0.75), alternating pressure (active) air surfaces (e.g. alternating pressure air mattresses, large-celled ripple mattresses) (RR 0.63, 95% CI 0.42 to 0.93), and reactive gel surfaces (e.g. gel pads used on operating tables) (RR 0.47, 95% CI 0.22 to 1.01) may reduce pressure ulcer incidence. The ranking of treatments in terms of effectiveness is also of very low certainty for all interventions. It is unclear which treatment is best for preventing ulceration. (2) Time to pressure ulcer incidence: four reviews had direct evidence on this outcome for seven comparisons. We included 10 studies (7211 participants; 699 participants with new ulcers) evaluating six interventions in a network meta-analysis. Again, data from most network contrasts (13/15) are of very low certainty. There is low-certainty evidence that, compared with foam surfaces (reference treatment), reactive air surfaces may reduce the hazard of developing new pressure ulcers (hazard ratio (HR) 0.20, 95% CI 0.04 to 1.05). The ranking of all support surfaces for preventing pressure ulcers in terms of time to healing is uncertain. (3) Cost-effectiveness: this overview includes direct evidence for three comparisons. For preventing pressure ulcers, alternating pressure air surfaces are probably more cost-effective than foam surfaces (moderate-certainty evidence). Pressure ulcer treatment: two reviews (of 12 studies with 972 participants) report direct evidence for five comparisons on: complete pressure ulcer healing, time to complete pressure ulcer healing, patient comfort response, adverse event rates, and cost-effectiveness. Here we focus on outcomes with some evidence at a minimum of low certainty. (1) Complete pressure ulcer healing: our overview includes direct evidence for five comparisons. There is uncertainty about the relative effects of beds, overlays and mattresses on ulcer healing. The corresponding network meta-analysis (with four studies, 397 participants) had only three direct contrasts and a total of six network contrasts. Again, most network contrasts (5/6) have very low-certainty evidence. There was low-certainty evidence that more people with pressure ulcers may heal completely using reactive air surfaces than using foam surfaces (RR 1.32, 95% CI 0.96 to 1.80). We are uncertain which surfaces have the highest probability of being the most effective (all very low-certainty evidence). (2) Time to complete pressure ulcer healing: this overview includes direct evidence for one comparison: people using reactive air surfaces may be more likely to have healed pressure ulcers compared with those using foam surfaces in long-term care settings (HR 2.66, 95% CI 1.34 to 5.17; low-certainty evidence). (3) Cost-effectiveness: this overview includes direct evidence for one comparison: compared with foam surfaces, reactive air surfaces may cost an extra 26 US dollars for every ulcer-free day in the first year of use in long-term care settings (low-certainty evidence). AUTHORS' CONCLUSIONS: Compared with foam surfaces, reactive air surfaces may reduce pressure ulcer risk and may increase complete ulcer healing. Compared with foam surfaces, alternating pressure air surfaces may reduce pressure ulcer risk and are probably more cost-effective in preventing pressure ulcers. Compared with foam surfaces, reactive gel surfaces may reduce pressure ulcer risk, particularly for people in operating rooms and long-term care settings. There are uncertainties for the relative effectiveness of other support surfaces for preventing and treating pressure ulcers, and their efficacy ranking. More high-quality research is required; for example, for the comparison of reactive air surfaces with alternating pressure air surfaces. Future studies should consider time-to-event outcomes and be designed to minimise any risk of bias.

Beds, overlays and mattresses for treating pressure ulcers.

BACKGROUND: Pressure ulcers (also known as pressure injuries, pressure sores, decubitus ulcers and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Beds, overlays or mattresses are widely used with the aim of treating pressure ulcers. OBJECTIVES: To assess the effects of beds, overlays and mattresses on pressure ulcer healing in people with pressure ulcers of any stage, in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to pressure-redistributing beds, overlays or mattresses. Comparators were any beds, overlays or mattresses that were applied for treating pressure ulcers. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. MAIN RESULTS: We included 13 studies (972 participants) in the review. Most studies were small (median study sample size: 72 participants). The average age of participants ranged from 64.0 to 86.5 years (median: 82.7 years) and all studies recruited people with existing pressure ulcers (the baseline ulcer area size ranging from 4.2 to 18.6 cm2,median 6.6 cm2). Participants were recruited from acute care settings (six studies) and community and long-term care settings (seven studies). Of the 13 studies, three (224 participants) involved surfaces that were not well described and therefore could not be classified. Additionally, six (46.2%) of the 13 studies presented findings which were considered at high overall risk of bias. We synthesised data for four comparisons in the review: alternating pressure (active) air surfaces versus foam surfaces; reactive air surfaces versus foam surfaces; reactive water surfaces versus foam surfaces, and a comparison between two types of alternating pressure (active) air surfaces. We summarise key findings for these four comparisons below. (1) Alternating pressure (active) air surfaces versus foam surfaces: we are uncertain if there is a difference between alternating pressure (active) air surfaces and foam surfaces in the proportion of participants whose pressure ulcers completely healed (two studies with 132 participants; the reported risk ratio (RR) in one study was 0.97, 95% confidence interval (CI) 0.26 to 3.58). There is also uncertainty for the outcomes of patient comfort (one study with 83 participants) and adverse events (one study with 49 participants). These outcomes have very low-certainty evidence. Included studies did not report time to complete ulcer healing, health-related quality of life, or cost effectiveness. (2) Reactive air surfaces versus foam surfaces: it is uncertain if there is a difference in the proportion of participants with completely healed pressure ulcers between reactive air surfaces and foam surfaces (RR 1.32, 95% CI 0.96 to 1.80; I2 = 0%; 2 studies, 156 participants; low-certainty evidence). When time to complete pressure ulcer healing is considered using a hazard ratio, data from one small study (84 participants) suggests a greater hazard for complete ulcer healing on reactive air surfaces (hazard ratio 2.66, 95% CI 1.34 to 5.17; low-certainty evidence). These results are sensitive to the choice of outcome measure so should be interpreted as uncertain. We are also uncertain whether there is any difference between these surfaces in patient comfort responses (1 study, 72 participants; very low-certainty evidence) and in adverse events (2 studies, 156 participants; low-certainty evidence). There is low-certainty evidence that reactive air surfaces may cost an extra 26 US dollars for every ulcer-free day in the first year of use (1 study, 87 participants). Included studies did not report health-related quality of life. (3) Reactive water surfaces versus foam surfaces: it is uncertain if there is a difference between reactive water surfaces and foam surfaces in the proportion of participants with healed pressure ulcers (RR 1.07, 95% CI 0.70 to 1.63; 1 study, 101 participants) and in adverse events (1 study, 120 participants). All these have very low-certainty evidence. Included studies did not report time to complete ulcer healing, patient comfort, health-related quality of life, or cost effectiveness. (4) Comparison between two types of alternating pressure (active) air surfaces: it is uncertain if there is a difference between Nimbus and Pegasus alternating pressure (active) air surfaces in the proportion of participants with healed pressure ulcers, in patient comfort responses and in adverse events: each of these outcomes had four studies (256 participants) but very low-certainty evidence. Included studies did not report time to complete ulcer healing, health-related quality of life, or cost effectiveness. AUTHORS' CONCLUSIONS: We are uncertain about the relative effects of most different pressure-redistributing surfaces for pressure ulcer healing (types directly compared are alternating pressure air surfaces versus foam surfaces, reactive air surfaces versus foam surfaces, reactive water surfaces versus foam surfaces, and Nimbus versus Pegasus alternating pressure (active) air surfaces). There is also uncertainty regarding the effects of these different surfaces on the outcomes of comfort and adverse events. However, people using reactive air surfaces may be more likely to have pressure ulcers completely healed than those using foam surfaces over 37.5 days' follow-up, and reactive air surfaces may cost more for each ulcer-free day than foam surfaces. Future research in this area could consider the evaluation of alternating pressure air surfaces versus foam surfaces as a high priority. Time-to-event outcomes, careful assessment of adverse events and trial-level cost-effectiveness evaluation should be considered in future studies. Further review using network meta-analysis will add to the findings reported here.

Alternating pressure (active) air surfaces for preventing pressure ulcers.

BACKGROUND: Pressure ulcers (also known as pressure injuries, pressure sores, decubitus ulcers and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Alternating pressure (active) air surfaces are widely used with the aim of preventing pressure ulcers. OBJECTIVES: To assess the effects of alternating pressure (active) air surfaces (beds, mattresses or overlays) compared with any support surface on the incidence of pressure ulcers in any population in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to alternating pressure (active) air beds, overlays or mattresses. Comparators were any beds, overlays or mattresses. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. MAIN RESULTS: We included 32 studies (9058 participants) in the review. Most studies were small (median study sample size: 83 participants). The average age of participants ranged from 37.2 to 87.0 years (median: 69.1 years). Participants were largely from acute care settings (including accident and emergency departments). We synthesised data for six comparisons in the review: alternating pressure (active) air surfaces versus: foam surfaces, reactive air surfaces, reactive water surfaces, reactive fibre surfaces, reactive gel surfaces used in the operating room followed by foam surfaces used on the ward bed, and another type of alternating pressure air surface. Of the 32 included studies, 25 (78.1%) presented findings which were considered at high overall risk of bias. PRIMARY OUTCOME: pressure ulcer incidence Alternating pressure (active) air surfaces may reduce the proportion of participants developing a new pressure ulcer compared with foam surfaces (risk ratio (RR) 0.63, 95% confidence interval (CI) 0.34 to 1.17; I2 = 63%; 4 studies, 2247 participants; low-certainty evidence). Alternating pressure (active) air surfaces applied on both operating tables and hospital beds may reduce the proportion of people developing a new pressure ulcer compared with reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds (RR 0.22, 95% CI 0.06 to 0.76; I2 = 0%; 2 studies, 415 participants; low-certainty evidence). It is uncertain whether there is a difference in the proportion of people developing new pressure ulcers between alternating pressure (active) air surfaces and the following surfaces, as all these comparisons have very low-certainty evidence: (1) reactive water surfaces; (2) reactive fibre surfaces; and (3) reactive air surfaces. The comparisons between different types of alternating pressure air surfaces are presented narratively. Overall, all comparisons suggest little to no difference between these surfaces in pressure ulcer incidence (7 studies, 2833 participants; low-certainty evidence). Included studies have data on time to pressure ulcer incidence for three comparisons. When time to pressure ulcer development is considered using a hazard ratio (HR), it is uncertain whether there is a difference in the risk of developing new pressure ulcers, over 90 days' follow-up, between alternating pressure (active) air surfaces and foam surfaces (HR 0.41, 95% CI 0.10 to 1.64; I2 = 86%; 2 studies, 2105 participants; very low-certainty evidence). For the comparison with reactive air surfaces, there is low-certainty evidence that people treated with alternating pressure (active) air surfaces may have a higher risk of developing an incident pressure ulcer than those treated with reactive air surfaces over 14 days' follow-up (HR 2.25, 95% CI 1.05 to 4.83; 1 study, 308 participants). Neither of the two studies with time to ulcer incidence data suggested a difference in the risk of developing an incident pressure ulcer over 60 days' follow-up between different types of alternating pressure air surfaces. Secondary outcomes The included studies have data on (1) support-surface-associated patient comfort for comparisons involving foam surfaces, reactive air surfaces, reactive fibre surfaces and alternating pressure (active) air surfaces; (2) adverse events for comparisons involving foam surfaces, reactive gel surfaces and alternating pressure (active) air surfaces; and (3) health-related quality of life outcomes for the comparison involving foam surfaces. However, all these outcomes and comparisons have low or very low-certainty evidence and it is uncertain whether there are any differences in these outcomes. Included studies have data on cost effectiveness for two comparisons. Moderate-certainty evidence suggests that alternating pressure (active) air surfaces are probably more cost-effective than foam surfaces (1 study, 2029 participants) and that alternating pressure (active) air mattresses are probably more cost-effective than overlay versions of this technology for people in acute care settings (1 study, 1971 participants). AUTHORS' CONCLUSIONS: Current evidence is uncertain about the difference in pressure ulcer incidence between using alternating pressure (active) air surfaces and other surfaces (reactive water surfaces, reactive fibre surfaces and reactive air surfaces). Alternating pressure (active) air surfaces may reduce pressure ulcer risk compared with foam surfaces and reactive gel surfaces used on operating tables followed by foam surfaces applied on hospital beds. People using alternating pressure (active) air surfaces may be more likely to develop new pressure ulcers over 14 days' follow-up than those treated with reactive air surfaces in the nursing home setting; but as the result is sensitive to the choice of outcome measure it should be interpreted cautiously. Alternating pressure (active) air surfaces are probably more cost-effective than reactive foam surfaces in preventing new pressure ulcers. Future studies should include time-to-event outcomes and assessment of adverse events and trial-level cost-effectiveness. Further review using network meta-analysis will add to the findings reported here.

Reactive air surfaces for preventing pressure ulcers.

BACKGROUND: Pressure ulcers (also known as pressure injuries, pressure sores, decubitus ulcers and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Reactive air surfaces (beds, mattresses or overlays) can be used for preventing pressure ulcers. OBJECTIVES: To assess the effects of reactive air beds, mattresses or overlays compared with any support surface on the incidence of pressure ulcers in any population in any setting. SEARCH METHODS: In November 2019, we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials that allocated participants of any age to reactive air beds, overlays or mattresses. Comparators were any beds, overlays or mattresses that were applied for preventing pressure ulcers. DATA COLLECTION AND ANALYSIS: At least two review authors independently assessed studies using predetermined inclusion criteria. We carried out data extraction, 'Risk of bias' assessment using the Cochrane 'Risk of bias' tool, and the certainty of the evidence assessment according to Grading of Recommendations, Assessment, Development and Evaluations methodology. If a reactive air surface was compared with surfaces that were not clearly specified, then we recorded and described the concerned study but did not included it in further data analyses. MAIN RESULTS: We included 17 studies (2604 participants) in this review. Most studies were small (median study sample size: 83 participants). The average participant age ranged from 56 to 87 years (median: 72 years). Participants were recruited from a wide range of care settings with the majority being acute care settings. Almost all studies were conducted in the regions of Europe and America. Of the 17 included studies, two (223 participants) compared reactive air surfaces with surfaces that were not well described and therefore could not be classified. We analysed data for five comparisons: reactive air surfaces compared with (1) alternating pressure (active) air surfaces (seven studies with 1728 participants), (2) foam surfaces (four studies with 229 participants), (3) reactive water surfaces (one study with 37 participants), (4) reactive gel surfaces (one study with 66 participants), and (5) another type of reactive air surface (two studies with 223 participants). Of the 17 studies, seven (41.2%) presented findings which were considered at high overall risk of bias. PRIMARY OUTCOME: Pressure ulcer incidence Reactive air surfaces may reduce the proportion of participants developing a new pressure ulcer compared with foam surfaces (risk ratio (RR) 0.42; 95% confidence interval (CI) 0.18 to 0.96; I2 = 25%; 4 studies, 229 participants; low-certainty evidence). It is uncertain if there is a difference in the proportions of participants developing a new pressure ulcer on reactive air surfaces compared with: alternating pressure (active) air surfaces (6 studies, 1648 participants); reactive water surfaces (1 study, 37 participants); reactive gel surfaces (1 study, 66 participants), or another type of reactive air surface (2 studies, 223 participants). Evidence for all these comparisons is of very low certainty. Included studies have data on time to pressure ulcer incidence for two comparisons. When time to pressure ulcer incidence is considered using a hazard ratio (HR), low-certainty evidence suggests that in the nursing home setting, people on reactive air surfaces may be less likely to develop a new pressure ulcer over 14 days' of follow-up than people on alternating pressure (active) air surfaces (HR 0.44; 95% CI 0.21 to 0.96; 1 study, 308 participants). It is uncertain if there is a difference in the hazard of developing new pressure ulcers between two types of reactive air surfaces (1 study, 123 participants; very low-certainty evidence). Secondary outcomes Support-surface-associated patient comfort: the included studies have data on this outcome for three comparisons. We could not pool any data as comfort outcome measures differed between included studies; therefore a narrative summary is provided. It is uncertain if there is a difference in patient comfort responses between reactive air surfaces and foam surfaces over the top of an alternating pressure (active) air surfaces (1 study, 72 participants), and between those using reactive air surfaces and those using alternating pressure (active) air surfaces (4 studies, 1364 participants). Evidence for these two comparisons is of very low certainty. It is also uncertain if there is a difference in patient comfort responses between two types of reactive air surfaces (1 study, 84 participants; low-certainty evidence). All reported adverse events: there were data on this outcome for one comparison: it is uncertain if there is a difference in adverse events between reactive air surfaces and foam surfaces (1 study, 72 participants; very low-certainty evidence). The included studies have no data for health-related quality of life and cost-effectiveness for all five comparisons. AUTHORS' CONCLUSIONS: Current evidence is uncertain regarding any differences in the relative effects of reactive air surfaces on ulcer incidence and patient comfort, when compared with reactive water surfaces, reactive gel surfaces, or another type of reactive air surface. Using reactive air surfaces may reduce the risk of developing new pressure ulcers compared with using foam surfaces. Also, using reactive air surfaces may reduce the risk of developing new pressure ulcers within 14 days compared with alternating pressure (active) air surfaces in people in a nursing home setting. Future research in this area should consider evaluation of the most important support surfaces from the perspective of decision-makers. Time-to-event outcomes, careful assessment of adverse events and trial-level cost-effectiveness evaluation should be considered in future studies. Trials should be designed to minimise the risk of detection bias; for example, by using digital photography and adjudicators of the photographs being blinded to group allocation. Further review using network meta-analysis will add to the findings reported here.

ANTECEDENTES: Las úlceras por presión (también conocidas como escaras o úlceras de decúbito) son lesiones localizadas en la piel o en los tejidos blandos subyacentes, o en ambos, causadas por la presión, el roce o la fricción no aliviados. Las superficies de aire estáticas (camas, colchones o sobrecolchones) se pueden utilizar para prevenir las úlceras por presión. OBJETIVOS: Evaluar los efectos de las camas, los colchones o los sobrecolchones de aire estáticos en comparación con cualquier superficie especial para el manejo de la presión (SEMP) sobre la incidencia de las úlceras por presión en cualquier población y en cualquier ámbito. MÉTODOS DE BÚSQUEDA: En noviembre de 2019 se hicieron búsquedas en el Registro especializado del Grupo Cochrane de Heridas (Cochrane Wounds), en el Registro Cochrane central de ensayos controlados (CENTRAL); Ovid MEDLINE (incluido In­Process & Other Non­Indexed Citations); Ovid Embase y EBSCO CINAHL Plus. También se buscaron estudios en curso y no publicados en los registros de ensayos clínicos, y se examinaron las listas de referencias de los estudios incluidos pertinentes, así como de las revisiones, los metanálisis y los informes de tecnología sanitaria para identificar estudios adicionales. No hubo restricciones en cuanto al idioma, la fecha de publicación ni el contexto de los estudios. CRITERIOS DE SELECCIÓN: Se incluyeron los ensayos controlados aleatorizados que asignaron a participantes de cualquier edad a camas, colchones o sobrecolchones de aire estáticos. Los comparadores fueron cualquier cama, colchón o sobrecolchón utilizados para prevenir las úlceras por presión. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Al menos dos autores de la revisión evaluaron de forma independiente los ensayos según criterios de inclusión predeterminados. Se realizó la extracción de los datos, la evaluación del riesgo de sesgo mediante la herramienta Cochrane "Risk of bias" y la evaluación de la certeza de la evidencia según el método Grading of Recommendations, Assessment, Development and Evaluations. Si se comparaba una superficie de aire estática con superficies que no estaban claramente especificadas, se registraba y describía el estudio en cuestión pero no se incluía en análisis de datos adicionales. RESULTADOS PRINCIPALES: En esta revisión se incluyeron 17 estudios (2604 participantes). La mayoría de los estudios eran pequeños (mediana del tamaño muestral de los estudios: 83 participantes). La media de edad de los participantes varió entre 56 y 87 años (mediana: 72 años). Los participantes fueron reclutados en una amplia variedad de ámbitos asistenciales, siendo la mayoría de ellos ámbitos de cuidados intensivos y de agudos. Casi todos los estudios se realizaron en las regiones de Europa y América. De los 17 estudios incluidos, dos (223 participantes) compararon superficies de aire estáticas con superficies que no estaban bien descritas y, por tanto, no pudieron clasificarse. Se analizaron los datos de cinco comparaciones: superficies de aire estáticas comparadas con (1) superficies de aire de presión alternante (activas) (siete estudios con 1728 participantes), (2) superficies de espuma (cuatro estudios con 229 participantes), (3) superficies de agua estáticas (un estudio con 37 participantes), (4) superficies de gel estáticas (un estudio con 66 participantes) y (5) otro tipo de superficies de aire estáticas (dos estudios con 223 participantes). De los 17 estudios incluidos, siete (41,2%) presentaron resultados que se consideraron con alto riesgo general de sesgo. Desenlace principal: incidencia de úlceras por presión Las superficies de aire estáticas podrían reducir la proporción de participantes que desarrollan nuevas úlceras por presión en comparación con las superficies de espuma (razón de riesgos [RR] 0,42; intervalo de confianza [IC] del 95%: 0,18 a 0,96; I2 = 25%; cuatro estudios, 229 participantes; evidencia de certeza baja). No se sabe si existe una diferencia en las proporciones de participantes que desarrollan una nueva úlcera por presión en superficies de aire estáticas en comparación con: superficies de aire de presión alternante (activas) (seis estudios, 1648 participantes); superficies de agua estáticas (un estudio, 37 participantes); superficies de gel estáticas (un estudio, 66 participantes) u otro tipo de superficies de aire estáticas (dos estudios, 223 participantes). La evidencia para todas estas comparaciones es de certeza muy baja. Los estudios incluidos cuentan con datos sobre el tiempo hasta la incidencia de úlceras por presión para dos comparaciones. Cuando el tiempo hasta la incidencia de la úlcera por presión se considera con el cociente de riesgos instantáneos (CRI), la evidencia de certeza baja indica que en el ámbito de las residencia de ancianos, las personas sobre superficies de aire estáticas podrían tener menos probabilidades de presentar una nueva úlcera por presión a lo largo de 14 días de seguimiento que las personas sobre superficies de aire de presión alternante (activas) (CRI 0,44; IC del 95%: 0,21 a 0,96; un estudio, 308 participantes). No se sabe si hay una diferencia en el riesgo de presentar nuevas úlceras por presión entre dos tipos de superficies de aire estáticas (un estudio, 123 participantes; evidencia de certeza muy baja). Desenlaces secundarios Comodidad del paciente asociada con la SEMP: los estudios incluidos contienen datos de tres comparaciones para este desenlace. No fue posible agrupar los datos puesto que las medidas de desenlace de comodidad difirieron entre los estudios incluidos; por lo tanto, se proporciona un resumen narrativo. No se sabe si existe una diferencia en las respuestas de comodidad del paciente entre las superficies de espuma y las superficies de aire estáticas sobre superficies de aire de presión alternante (activas) (un estudio, 72 participantes) ni entre aquellos que utilizaron superficies de aire estáticas y los que utilizaron superficies de aire de presión alternante (activas) (cuatro estudios, 1364 participantes). La evidencia para estas dos comparaciones es de certeza muy baja. Tampoco se sabe si hay una diferencia en las respuestas de comodidad de los pacientes entre dos tipos de superficies de aire estáticas (un estudio, 84 participantes; evidencia de certeza baja). Todos los eventos adversos notificados: hubo datos sobre este desenlace para una comparación: no se sabe si existe una diferencia en los eventos adversos entre las superficies de aire estáticas y las superficies de espuma (un estudio, 72 participantes; evidencia de certeza muy baja). Los estudios incluidos no tienen datos sobre la calidad de vida relacionada con la salud y la coste­efectividad para ninguna de las cinco comparaciones. CONCLUSIONES DE LOS AUTORES: La evidencia actual es incierta en cuanto a las diferencias en los efectos relativos de las superficies de aire estáticas sobre la incidencia de úlceras y la comodidad del paciente, cuando se compararon con las superficies de agua estáticas, las superficies de gel estáticas u otro tipo de superficies de aire estáticas. El uso de superficies de aire estáticas podría reducir el riesgo de aparición de nuevas úlceras por presión en comparación con el uso de superficies de espuma. Además, el uso de superficies de aire estáticas podría reducir el riesgo de aparición de nuevas úlceras por presión en los 14 días siguientes en comparación las superficies de aire de presión alternante (activas) en personas en una residencia de ancianos. Los estudios de investigación futuros en este campo deberían considerar la evaluación de las SEMP más importantes desde la perspectiva de aquellos que toman decisiones. En los estudios futuros se deben considerar los desenlaces de tiempo hasta el evento, la evaluación cuidadosa de los eventos adversos y la evaluación de la coste­efectividad a nivel de ensayo. Los ensayos deben estar diseñados para minimizar el riesgo de sesgo de detección; por ejemplo, con el uso de fotografía digital y el cegamiento de los adjudicatarios de las fotografías a la asignación a los grupos. Una revisión posterior mediante metanálisis en red ampliará los resultados aquí proporcionados.

Serious adverse events reported in placebo randomised controlled trials of oral naltrexone: a systematic review and meta-analysis.

BACKGROUND: Naltrexone is an opioid antagonist used in many different conditions, both licensed and unlicensed. It is used at widely varying doses from 3 to 250 mg. The aim of this review was to extensively evaluate the safety of oral naltrexone by examining the risk of serious adverse events and adverse events in randomised controlled trials of naltrexone compared to placebo. METHODS: A systematic search of the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, other databases and clinical trials registries was undertaken up to May 2018. Parallel placebo-controlled randomised controlled trials longer than 4 weeks published after 1 January 2001 of oral naltrexone at any dose were selected. Any condition or age group was included, excluding only studies in opioid or ex-opioid users owing to possible opioid/opioid antagonist interactions. The systematic review used the guidance of the Cochrane Handbook and Preferred Reporting Items for Systematic Reviews and Meta-analyses harms checklist throughout. Numerical data were independently extracted by two people and cross-checked. Risk of bias was assessed with the Cochrane risk-of-bias tool. Meta-analyses were performed in R using random effects models throughout. RESULTS: Eighty-nine randomised controlled trials with 11,194 participants were found, studying alcohol use disorders (n = 38), various psychiatric disorders (n = 13), impulse control disorders (n = 9), other addictions including smoking (n = 18), obesity or eating disorders (n = 6), Crohn's disease (n = 2), fibromyalgia (n = 1) and cancers (n = 2). Twenty-six studies (4,960 participants) recorded serious adverse events occurring by arm of study. There was no evidence of increased risk of serious adverse events for naltrexone compared to placebo (risk ratio 0.84, 95% confidence interval 0.66-1.06). Sensitivity analyses pooling risk differences supported this conclusion (risk difference -0.01, 95% confidence interval -0.02-0.00) and subgroup analyses showed that results were consistent across different doses and disease groups. Secondary analysis revealed only six marginally significant adverse events for naltrexone compared to placebo, which were of mild severity. CONCLUSIONS: Naltrexone does not appear to increase the risk of serious adverse events over placebo. These findings confirm the safety of oral naltrexone when used in licensed indications and encourage investments to undertake efficacy studies in unlicensed indications. TRIAL REGISTRATION: PROSPERO 2017 CRD42017054421 .

Chlorhexidine bathing of the critically ill for the prevention of hospital-acquired infection.

BACKGROUND: Hospital-acquired infection is a frequent adverse event in patient care; it can lead to longer stays in the intensive care unit (ICU), additional medical complications, permanent disability or death. Whilst all hospital-based patients are susceptible to infections, prevalence is particularly high in the ICU, where people who are critically ill have suppressed immunity and are subject to increased invasive monitoring. People who are mechanically-ventilated are at infection risk due to tracheostomy and reintubation and use of multiple central venous catheters, where lines and tubes may act as vectors for the transmission of bacteria and may increase bloodstream infections and ventilator-associated pneumonia (VAP). Chlorhexidine is a low-cost product, widely used as a disinfectant and antiseptic, which may be used to bathe people who are critically ill with the aim of killing bacteria and reducing the spread of hospital-acquired infections. OBJECTIVES: To assess the effects of chlorhexidine bathing on the number of hospital-acquired infections in people who are critically ill. SEARCH METHODS: In December 2018 we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trial registries for ongoing and unpublished studies, and checked reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that compared chlorhexidine bathing with soap-and-water bathing of patients in the ICU. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed study eligibility, extracted data and undertook risk of bias and GRADE assessment of the certainty of the evidence . MAIN RESULTS: We included eight studies in this review. Four RCTs included a total of 1537 individually randomised participants, and four cluster-randomised cross-over studies included 23 randomised ICUs with 22,935 participants. We identified one study awaiting classification, for which we were unable to assess eligibility.The studies compared bathing using 2% chlorhexidine-impregnated washcloths or dilute solutions of 4% chlorhexidine versus soap-and-water bathing or bathing with non-antimicrobial washcloths.Eight studies reported data for participants who had a hospital-acquired infection during the ICU stay. We are uncertain whether using chlorhexidine for bathing of critically ill people reduces the rate of hospital-acquired infection, because the certainty of the evidence is very low (rate difference 1.70, 95% confidence interval (CI) 0.12 to 3.29; 21,924 participants). Six studies reported mortality (in hospital, in the ICU, and at 48 hours). We cannot be sure whether using chlorhexidine for bathing of critically-ill people reduces mortality, because the certainty of the evidence is very low (odds ratio 0.87, 95% CI 0.76 to 0.99; 15,798 participants). Six studies reported length of stay in the ICU. We noted that individual studies found no evidence of a difference in length of stay; we did not conduct meta-analysis because data were skewed. It is not clear whether using chlorhexidine for bathing of critically ill people reduced length of stay in the ICU, because the certainty of the evidence is very low. Seven studies reported skin reactions as an adverse event, and five of these reported skin reactions which were thought to be attributable to the bathing solution. Data in these studies were reported inconsistently and we were unable to conduct meta-analysis; we cannot tell whether using chlorhexidine for bathing of critically ill people reduced adverse events, because the certainty of the evidence is very low.We used the GRADE approach to downgrade the certainty of the evidence of each outcome to very low. For all outcomes, we downgraded evidence because of study limitations (most studies had a high risk of performance bias, and we noted high risks of other bias in some studies). We downgraded evidence due to indirectness, because some participants in studies may have had hospital-acquired infections before recruitment. We noted that one small study had a large influence on the effect for hospital-acquired infections, and we assessed decisions made in analysis of some cluster-randomised cross-over studies on the effect for hospital-acquired infections and for mortality; we downgraded the evidence for these outcomes due to inconsistency. We also downgraded the evidence on length of stay in the ICU, because of imprecision. Data for adverse events were limited by few events and so we downgraded for imprecision. AUTHORS' CONCLUSIONS: Due to the very low-certainty evidence available, it is not clear whether bathing with chlorhexidine reduces hospital-acquired infections, mortality, or length of stay in the ICU, or whether the use of chlorhexidine results in more skin reactions.

The effect of commitment-making on weight loss and behaviour change in adults with obesity/overweight; a systematic review.

BACKGROUND: Adherence to weight loss interventions is crucial to successful outcomes, yet little is known about how best to improve it. This suggests a need for developing and improving adherence strategies, such as formal commitments. This review aims to identify the effect of including a commitment device alongside lifestyle interventions on weight loss, and identify the most appropriate delivery mechanisms and target behaviours. METHODS: We searched five databases and hand-searched reference lists for trials of behavioural interventions to achieve weight loss among adults with excess weight or obesity. Interventions incorporating commitment devices were included in a narrative review and meta-analysis where appropriate. Commitment devices with financial incentives were excluded. RESULTS: Of 2675 unique studies, ten met the inclusion criteria. Data from three randomised trials including 409 participants suggests that commitment interventions increases short-term weight loss by a mean of 1.5 kg (95% CI: 0.7, 2.4). Data from two randomised trials including 302 patients suggests that benefits were sustained at 12 months (mean difference 1.7 kg; 95% CI: 0.0, 3.4). Commitment devices appeared most successful when made publicly, and targeting diet rather than physical activity. CONCLUSIONS: Using commitment devices, such as behavioural contracts, as part of a weight loss intervention may be useful in improving weight loss outcomes and dietary changes, at least in the short-term. However, evidence is limited and of variable quality so results must be interpreted with caution. Poor reporting of intervention details may have limited the number of identified studies. More rigorous methodology and longer term follow-ups are required to determine the effectiveness of behavioural contracts given their potential for use in public health interventions.

Does pre-existing cognitive impairment impact on amount of stroke rehabilitation received? An observational cohort study.

OBJECTIVE: To examine whether stroke survivors in inpatient rehabilitation with pre-existing cognitive impairment receive less therapy than those without. DESIGN: Prospective observational cohort. SETTING: Four UK inpatient stroke rehabilitation units. PARTICIPANTS: A total of 139 stroke patients receiving rehabilitation, able to give informed consent/had an individual available to act as personal consultee. In total, 33 participants were categorized with pre-existing cognitive impairment based on routine documentation by clinicians and 106 without. MEASURES: Number of inpatient therapy sessions received during the first eight weeks post-stroke, referral to early supported discharge, and length of stay. RESULTS: On average, participants with pre-existing cognitive impairment received 40 total physiotherapy and occupational therapy sessions compared to 56 for those without (mean difference = 16.0, 95% confidence interval (CI) = 2.9, 29.2), which was not fully explained by adjusting for potential confounders (age, sex, National Institutes of Health Stroke Scale (NIHSS), and pre-stroke modified Rankin Scale (mRS)). While those with pre-existing cognitive impairment received nine fewer single-discipline physiotherapy sessions (95% CI = 3.7, 14.8), they received similar amounts of single-discipline occupational therapy, psychology, and speech and language therapy; two more non-patient-facing occupational therapy sessions (95% CI = -4.3, -0.6); and nine fewer patient-facing occupational therapy sessions (95% CI = 3.5, 14.9). There was no evidence to suggest they were discharged earlier, but of the 85 participants discharged within eight weeks, 8 (42%) with pre-existing cognitive impairment were referred to early supported discharge compared to 47 (75%) without. CONCLUSION: People in stroke rehabilitation with pre-existing cognitive impairments receive less therapy than those without, but it remains unknown whether this affects outcomes.