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1.
Lancet ; 403(10429): 838-849, 2024 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-38364839

RESUMEN

BACKGROUND: Individuals with serum antibodies to citrullinated protein antigens (ACPA), rheumatoid factor, and symptoms, such as inflammatory joint pain, are at high risk of developing rheumatoid arthritis. In the arthritis prevention in the pre-clinical phase of rheumatoid arthritis with abatacept (APIPPRA) trial, we aimed to evaluate the feasibility, efficacy, and acceptability of treating high risk individuals with the T-cell co-stimulation modulator abatacept. METHODS: The APIPPRA study was a randomised, double-blind, multicentre, parallel, placebo-controlled, phase 2b clinical trial done in 28 hospital-based early arthritis clinics in the UK and three in the Netherlands. Participants (aged ≥18 years) at risk of rheumatoid arthritis positive for ACPA and rheumatoid factor with inflammatory joint pain were recruited. Exclusion criteria included previous episodes of clinical synovitis and previous use of corticosteroids or disease-modifying antirheumatic drugs. Participants were randomly assigned (1:1) using a computer-generated permuted block randomisation (block sizes of 2 and 4) stratified by sex, smoking, and country, to 125 mg abatacept subcutaneous injections weekly or placebo for 12 months, and then followed up for 12 months. Masking was achieved by providing four kits (identical in appearance and packaging) with pre-filled syringes with coded labels of abatacept or placebo every 3 months. The primary endpoint was the time to development of clinical synovitis in three or more joints or rheumatoid arthritis according to American College of Rheumatology and European Alliance of Associations for Rheumatology 2010 criteria, whichever was met first. Synovitis was confirmed by ultrasonography. Follow-up was completed on Jan 13, 2021. All participants meeting the intention-to-treat principle were included in the analysis. This trial was registered with EudraCT (2013-003413-18). FINDINGS: Between Dec 22, 2014, and Jan 14, 2019, 280 individuals were evaluated for eligibility and, of 213 participants, 110 were randomly assigned to abatacept and 103 to placebo. During the treatment period, seven (6%) of 110 participants in the abatacept group and 30 (29%) of 103 participants in the placebo group met the primary endpoint. At 24 months, 27 (25%) of 110 participants in the abatacept group had progressed to rheumatoid arthritis, compared with 38 (37%) of 103 in the placebo group. The estimated proportion of participants remaining arthritis-free at 12 months was 92·8% (SE 2·6) in the abatacept group and 69·2% (4·7) in the placebo group. Kaplan-Meier arthritis-free survival plots over 24 months favoured abatacept (log-rank test p=0·044). The difference in restricted mean survival time between groups was 53 days (95% CI 28-78; p<0·0001) at 12 months and 99 days (95% CI 38-161; p=0·0016) at 24 months in favour of abatacept. During treatment, abatacept was associated with improvements in pain scores, functional wellbeing, and quality-of-life measurements, as well as low scores of subclinical synovitis by ultrasonography, compared with placebo. However, the effects were not sustained at 24 months. Seven serious adverse events occurred in the abatacept group and 11 in the placebo group, including one death in each group deemed unrelated to treatment. INTERPRETATION: Therapeutic intervention during the at-risk phase of rheumatoid arthritis is feasible, with acceptable safety profiles. T-cell co-stimulation modulation with abatacept for 12 months reduces progression to rheumatoid arthritis, with evidence of sustained efficacy beyond the treatment period, and with no new safety signals. FUNDING: Bristol Myers Squibb.


Asunto(s)
Artritis Reumatoide , Sinovitis , Adolescente , Adulto , Humanos , Abatacept/efectos adversos , Artralgia , Artritis Reumatoide/tratamiento farmacológico , Dolor , Factor Reumatoide
2.
Thorax ; 79(6): 515-523, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38471792

RESUMEN

RATIONALE: Heterogeneity of the host response within sepsis, acute respiratory distress syndrome (ARDS) and more widely critical illness, limits discovery and targeting of immunomodulatory therapies. Clustering approaches using clinical and circulating biomarkers have defined hyper-inflammatory and hypo-inflammatory subphenotypes in ARDS associated with differential treatment response. It is unknown if similar subphenotypes exist in sepsis populations where leucocyte transcriptomic-defined subphenotypes have been reported. OBJECTIVES: We investigated whether inflammatory clusters based on cytokine protein abundance were seen in sepsis, and the relationships with previously described transcriptomic subphenotypes. METHODS: Hierarchical cluster and latent class analysis were applied to an observational study (UK Genomic Advances in Sepsis (GAinS)) (n=124 patients) and two clinical trial datasets (VANISH, n=155 and LeoPARDS, n=484) in which the plasma protein abundance of 65, 21, 11 circulating cytokines, cytokine receptors and regulators were quantified. Clinical features, outcomes, response to trial treatments and assignment to transcriptomic subphenotypes were compared between inflammatory clusters. MEASUREMENTS AND MAIN RESULTS: We identified two (UK GAinS, VANISH) or three (LeoPARDS) inflammatory clusters. A group with high levels of pro-inflammatory and anti-inflammatory cytokines was seen that was associated with worse organ dysfunction and survival. No interaction between inflammatory clusters and trial treatment response was found. We found variable overlap of inflammatory clusters and leucocyte transcriptomic subphenotypes. CONCLUSIONS: These findings demonstrate that differences in response at the level of cytokine biology show clustering related to severity, but not treatment response, and may provide complementary information to transcriptomic sepsis subphenotypes. TRIAL REGISTRATION NUMBER: ISRCTN20769191, ISRCTN12776039.


Asunto(s)
Citocinas , Fenotipo , Sepsis , Transcriptoma , Humanos , Sepsis/sangre , Sepsis/genética , Masculino , Citocinas/sangre , Femenino , Persona de Mediana Edad , Leucocitos/metabolismo , Biomarcadores/sangre , Anciano , Análisis por Conglomerados , Síndrome de Dificultad Respiratoria/sangre , Síndrome de Dificultad Respiratoria/genética , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Resultado del Tratamiento
3.
Surg Radiol Anat ; 46(8): 1219-1230, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38888835

RESUMEN

PURPOSE: The literature has for too long described the arterial supply of the mandible as coming from a single artery, the inferior alveolar artery, and being of the terminal type. Rather, it appears to come from an extensive and complex arterial network dependent on the lingual, facial, and maxillary arteries and their collateral branches. Our study aims to confirm and demonstrate the arterial vascular richness of the mandible and to establish arterial mapping. METHODS: The arterial vascularization of the mandible was revealed in six anatomic specimens after performing selective injections of the lingual, facial, and maxillary arteries with different dyes. A specimen was injected intra-arterially with colored latex at the level of the maxillary artery for a morphometric study. RESULTS: Eighteen selective arterial injections were performed on six anatomic specimens. The mucocutaneous, musculoperiosteal, and intramedullary vascularizations were analyzed. Each of the arteries has a defined and delimited cutaneo-mucous vascular territory. The facial and maxillary arteries supply the musculoperiosteal vascularization of the mandible from the condyle to the symphysis. The lingual artery supplies only the inner cortex of the parasymphyseal and symphyseal regions. The facial and maxillary arteries provide intramedullary vascularization from the angle of the mandible to the parasymphysis. The vascularization of the symphysis depends on the facial artery. No staining was found in the condyle region. Neoprene latex injection was performed on an anatomic specimen, revealing a permeable anastomosis between the inferior alveolar and facial arteries. CONCLUSION: The arterial vascularization of the mandible is dependent on the maxillary, facial, and lingual arteries. This is a network vasculature. This study makes it possible to establish an arterial map of the mandible. The presence of an anastomosis between the inferior alveolar artery and the facial artery confirms the existence of dynamic and borrowed vascularization. Knowledge of this arterial system makes it possible to adapt maxillofacial surgical care and to anticipate possible intraoperative complications.


Asunto(s)
Arterias , Mandíbula , Humanos , Mandíbula/irrigación sanguínea , Mandíbula/anatomía & histología , Arterias/anatomía & histología , Cadáver , Masculino , Femenino , Arteria Maxilar/anatomía & histología
4.
Diabet Med ; 40(10): e15165, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37307016

RESUMEN

AIMS: To estimate the prevalence of undiagnosed diabetes and suboptimally controlled diabetes and the associated risk factors by community screening in India. METHODS: In this multi-centre, cross-sectional study, house-to-house screening was conducted in people aged ≥40 years in urban and rural areas across 10 states and one union territory in India between November 2018 and March 2020. Participants underwent anthropometry, clinical and biochemical assessments. Capillary random blood glucose and point-of-care glycated haemoglobin (HbA1c ) were used to diagnose diabetes. The prevalence of undiagnosed diabetes and suboptimal control (HbA1c ≥53 mmol/mol [≥7%]) among those with known diabetes was assessed. RESULTS: Among the 42,146 participants screened (22,150 urban, 19,996 rural), 5689 had known diabetes. The age-standardised prevalence of known diabetes was 13.1% (95% CI 12.8-13.4); 17.2% in urban areas and 9.4% in rural areas. The age-standardised prevalence of undiagnosed diabetes was 6.0% (95% CI 5.7-6.2); similar in both urban and rural areas with the highest proportions seen in the East (8.0%) and South (7.8%) regions. When we consider all people with diabetes in the population, 22.8% of individuals in urban areas and 36.7% in rural areas had undiagnosed diabetes. Almost 75% of the individuals with known diabetes had suboptimal glycaemic control. CONCLUSIONS: High prevalence of undiagnosed diabetes and suboptimally controlled diabetes emphasises the urgent need to identify and optimally treat people with diabetes to reduce the burden of diabetes.


Asunto(s)
Diabetes Mellitus , Humanos , Estudios Transversales , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Factores de Riesgo , Hemoglobina Glucada , Población Rural , Prevalencia , India/epidemiología , Glucemia , Población Urbana
5.
Nicotine Tob Res ; 25(7): 1319-1329, 2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37055073

RESUMEN

INTRODUCTION: Learned smoking cues from a smoker's environment are a major cause of lapse and relapse. Quit Sense, a theory-guided Just-In-Time Adaptive Intervention smartphone app, aims to help smokers learn about their situational smoking cues and provide in-the-moment support to help manage these when quitting. METHODS: A two-arm feasibility randomized controlled trial (N = 209) to estimate parameters to inform a definitive evaluation. Smoker's willing to make a quit attempt were recruited using online paid-for adverts and randomized to "usual care" (text message referral to NHS SmokeFree website) or "usual care" plus a text message invitation to install Quit Sense. Procedures, excluding manual follow-up for nonresponders, were automated. Follow-up at 6 weeks and 6 months included feasibility, intervention engagement, smoking-related, and economic outcomes. Abstinence was verified using cotinine assessment from posted saliva samples. RESULTS: Self-reported smoking outcome completion rates at 6 months were 77% (95% CI 71%, 82%), viable saliva sample return rate was 39% (95% CI 24%, 54%), and health economic data 70% (95% CI 64%, 77%). Among Quit Sense participants, 75% (95% CI 67%, 83%) installed the app and set a quit date and, of those, 51% engaged for more than one week. The 6-month biochemically verified sustained abstinence rate (anticipated primary outcome for definitive trial), was 11.5% (12/104) among Quit Sense participants and 2.9% (3/105) for usual care (adjusted odds ratio = 4.57, 95% CIs 1.23, 16.94). No evidence of between-group differences in hypothesized mechanisms of action was found. CONCLUSIONS: Evaluation feasibility was demonstrated alongside evidence supporting the effectiveness potential of Quit Sense. IMPLICATIONS: Running a primarily automated trial to initially evaluate Quit Sense was feasible, resulting in modest recruitment costs and researcher time, and high trial engagement. When invited, as part of trial participation, to install a smoking cessation app, most participants are likely to do so, and, for those using Quit Sense, an estimated one-half will engage with it for more than 1 week. Evidence that Quit Sense may increase verified abstinence at 6-month follow-up, relative to usual care, was generated, although low saliva return rates to verify smoking status contributed to considerable imprecision in the effect size estimate.


Asunto(s)
Aplicaciones Móviles , Cese del Hábito de Fumar , Humanos , Cese del Hábito de Fumar/métodos , Estudios de Factibilidad , Fumar , Autoinforme
6.
Thorax ; 77(10): 950-959, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34716281

RESUMEN

BACKGROUND AND AIMS: The chemoattractant receptor-homologous molecule expressed on T helper type 2 cells (CRTH2) antagonist timapiprant improved lung function and asthma control in a phase 2 study, with evidence suggesting reduced exacerbations. We aimed to assess whether timapiprant attenuated or prevented asthma exacerbations induced by experimental rhinovirus (RV) infection. We furthermore hypothesised that timapiprant would dampen RV-induced type 2 inflammation and consequently improve antiviral immune responses. METHODS: Atopic patients with partially controlled asthma on maintenance inhaled corticosteroids were randomised to timapiprant (n=22) or placebo (n=22) and challenged with RV-A16 3 weeks later. The primary endpoint was the cumulative lower respiratory symptom score over the 14 days post infection. Upper respiratory symptoms, spirometry, airway hyperresponsiveness, exhaled nitric oxide, RV-A16 virus load and soluble mediators in upper and lower airways samples, and CRTH2 staining in bronchial biopsies were additionally assessed before and during RV-A16 infection. RESULTS: Six subjects discontinued the study and eight were not infected; outcomes were assessed in 16 timapiprant-treated and 14 placebo-treated, successfully infected subjects. There were no differences between treatment groups in clinical exacerbation severity including cumulative lower respiratory symptom score day 0-14 (difference 3.0 (95% CI -29.0 to 17.0), p=0.78), virus load, antiviral immune responses, or RV-A16-induced airway inflammation other than in the bronchial biopsies, where CRTH2 staining was increased during RV-A16 infection in the placebo-treated but not the timapiprant-treated group. Timapiprant had a favourable safety profile, with no deaths, serious adverse events or drug-related withdrawals. CONCLUSION: Timapiprant treatment had little impact on the clinicopathological changes induced by RV-A16 infection in partially controlled asthma.


Asunto(s)
Asma , Rhinovirus , Humanos , Proyectos Piloto , Corticoesteroides/uso terapéutico , Inflamación
7.
BMC Med Res Methodol ; 22(1): 70, 2022 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-35300611

RESUMEN

INTRODUCTION: Novel screening tests used to detect a target condition are compared against either a reference standard or other existing screening methods. However, as it is not always possible to apply the reference standard on the whole population under study, verification bias is introduced. Statistical methods exist to adjust estimates to account for this bias. We extend common methods to adjust for verification bias when multiple tests are compared to a reference standard using data from a prospective double blind screening study for prostate cancer. METHODS: Begg and Greenes method and multiple imputation are extended to include the results of multiple screening tests which determine condition verification status. These two methods are compared to the complete case analysis using the IP1-PROSTAGRAM study data. IP1-PROSTAGRAM used a paired-cohort double-blind design to evaluate the use of imaging as alternative tests to screen for prostate cancer, compared to a blood test called prostate specific antigen (PSA). Participants with positive imaging (index) and/or PSA (control) underwent a prostate biopsy (reference standard). RESULTS: When comparing complete case results to Begg and Greenes and methods of multiple imputation there is a statistically significant increase in the specificity estimates for all screening tests. Sensitivity estimates remained similar across the methods, with completely overlapping 95% confidence intervals. Negative predictive value (NPV) estimates were higher when adjusting for verification bias, compared to complete case analysis, even though the 95% confidence intervals overlap. Positive predictive value (PPV) estimates were similar across all methods. CONCLUSION: Statistical methods are required to adjust for verification bias in accuracy estimates of screening tests. Expanding Begg and Greenes method to include multiple screening tests can be computationally intensive, hence multiple imputation is recommended, especially as it can be modified for low prevalence of the target condition.


Asunto(s)
Tamizaje Masivo , Antígeno Prostático Específico , Sesgo , Método Doble Ciego , Humanos , Masculino , Estudios Prospectivos , Sensibilidad y Especificidad
8.
PLoS Med ; 17(3): e1003046, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32142507

RESUMEN

BACKGROUND: The majority of people do not achieve recommended levels of physical activity. There is a need for effective, scalable interventions to promote activity. Self-monitoring by pedometer is a potentially suitable strategy. We assessed the effectiveness and cost-effectiveness of a very brief (5-minute) pedometer-based intervention ('Step It Up') delivered as part of National Health Service (NHS) Health Checks in primary care. METHODS AND FINDINGS: The Very Brief Intervention (VBI) Trial was a two parallel-group, randomised controlled trial (RCT) with 3-month follow-up, conducted in 23 primary care practices in the East of England. Participants were 1,007 healthy adults aged 40 to 74 years eligible for an NHS Health Check. They were randomly allocated (1:1) using a web-based tool between October 1, 2014, and December 31, 2015, to either intervention (505) or control group (502), stratified by primary care practice. Participants were aware of study group allocation. Control participants received the NHS Health Check only. Intervention participants additionally received Step It Up: a 5-minute face-to-face discussion, written materials, pedometer, and step chart. The primary outcome was accelerometer-based physical activity volume at 3-month follow-up adjusted for sex, 5-year age group, and general practice. Secondary outcomes included time spent in different intensities of physical activity, self-reported physical activity, and economic measures. We conducted an in-depth fidelity assessment on a subsample of Health Check consultations. Participants' mean age was 56 years, two-thirds were female, they were predominantly white, and two-thirds were in paid employment. The primary outcome was available in 859 (85.3%) participants. There was no significant between-group difference in activity volume at 3 months (adjusted intervention effect 8.8 counts per minute [cpm]; 95% CI -18.7 to 36.3; p = 0.53). We found no significant between-group differences in the secondary outcomes of step counts per day, time spent in moderate or vigorous activity, time spent in vigorous activity, and time spent in moderate-intensity activity (accelerometer-derived variables); as well as in total physical activity, home-based activity, work-based activity, leisure-based activity, commuting physical activity, and screen or TV time (self-reported physical activity variables). Of the 505 intervention participants, 491 (97%) received the Step it Up intervention. Analysis of 37 intervention consultations showed that 60% of Step it Up components were delivered faithfully. The intervention cost £18.04 per participant. Incremental cost to the NHS per 1,000-step increase per day was £96 and to society was £239. Adverse events were reported by 5 intervention participants (of which 2 were serious) and 5 control participants (of which 2 were serious). The study's limitations include a participation rate of 16% and low return of audiotapes by practices for fidelity assessment. CONCLUSIONS: In this large well-conducted trial, we found no evidence of effect of a plausible very brief pedometer intervention embedded in NHS Health Checks on objectively measured activity at 3-month follow-up. TRIAL REGISTRATION: Current Controlled Trials (ISRCTN72691150).


Asunto(s)
Actigrafía/instrumentación , Ejercicio Físico , Monitores de Ejercicio , Estilo de Vida Saludable , Atención Primaria de Salud , Medicina Estatal , Actigrafía/economía , Adulto , Anciano , Análisis Costo-Beneficio , Inglaterra , Femenino , Monitores de Ejercicio/economía , Costos de la Atención en Salud , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Atención Primaria de Salud/economía , Medicina Estatal/economía , Factores de Tiempo
9.
J Med Internet Res ; 22(5): e16629, 2020 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-32427113

RESUMEN

BACKGROUND: The efficacy of a highly tailored digital intervention to support medication adherence and feasibility to support clinical effectiveness as an adjunct to the primary care setting has not been evaluated. OBJECTIVE: This trial aimed to assess the behavioral efficacy of a highly tailored digital intervention to support medication adherence and to evaluate the feasibility of its clinical effectiveness, in patients with either or both hypertension and type 2 diabetes. We also examined quality of life and mechanisms of behavior change. Intervention fidelity, engagement, and satisfaction were also explored. METHODS: This was a multicenter, individually randomized controlled trial of 2 parallel groups: an intervention group that received a highly tailored text message and interactive voice response intervention for 12 weeks, and a control group that received usual care. Medication adherence was measured using self-reports and assessor-blinded practice records of a repeat prescription. Systolic blood pressure and glucose levels were assessed by nurses blinded to group allocation during practice visits at 3 months follow-up. Questionnaires obtained data to assess intervention mechanisms of action and satisfaction and digital log files captured data to evaluate fidelity and engagement. RESULTS: A total of 135 nonadherent patients (62/135, 46% female; 122/135, 90.3%; aged above 50 years) were randomly allocated in the intervention (n=79) or in the control group (n=56); of whom 13% (18/135) were lost at follow-up. Medication adherence was significantly improved in the intervention group compared with the control group (t116=2.27; P=.02, 2-tailed). Systolic blood pressure was 0.6 mmHg (95% CI -7.423 to 6.301), and hemoglobin A1c was 4.5 mmol/mol (95% CI -13.099 to 4.710) lower in the intervention group compared with the control group. Changes in intentional nonadherence and nonintentional nonadherence explained the improvements in medication adherence in the intervention group (beta=.074, SE=0.464; P=.04), but not in the control group (beta=.00, SE 1.35; P=.37). The intervention had 100% fidelity, a median of 12 days of engagement, and 76% overall satisfaction. CONCLUSIONS: Our trial is the first that has been conducted in the United Kingdom and showed that among nonadherent patients with either or both hypertension and type 2 diabetes, a highly tailored digital intervention was effective at improving treatment adherence and feasible to obtain clinically meaningful outcomes. Changes in intentional and nonintentional nonadherence predicted the improvements in medication adherence. The intervention had high fidelity, engagement, and satisfaction. Future research using a rigorous design is needed to evaluate the clinical effectiveness and cost-effectiveness of the intervention in primary care. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN) 10668149; http://www.controlled-trials.com/ISRCTN10668149.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipertensión/tratamiento farmacológico , Cumplimiento de la Medicación/estadística & datos numéricos , Calidad de Vida/psicología , Envío de Mensajes de Texto/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diabetes Mellitus Tipo 2/psicología , Estudios de Factibilidad , Femenino , Humanos , Hipertensión/psicología , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Reino Unido , Adulto Joven
10.
Phys Rev Lett ; 123(8): 088101, 2019 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-31491227

RESUMEN

A biomimetic model of cell-cell communication was developed to probe the passive molecular transport across ion channels inserted in synthetic lipid bilayers formed between contacting droplets arranged in a linear array. Diffusion of a fluorescent probe across the array was measured for different pore concentrations. The diffusion characteristic timescale is found to vary nonlinearly with the pore concentration. Our measurements are successfully modeled by a continuous time random walk description whose waiting time is the first exit time from a droplet through a cluster of pores. The size of the cluster of pores is found to increase with their concentration. Our results provide a direct link between the mesoscopic permeation properties and the microscopic characteristics of the pores, such as their number, size, and spatial arrangement.

11.
Crit Care ; 23(1): 156, 2019 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-31053084

RESUMEN

BACKGROUND: Randomised controlled trials (RCTs) enrolling patients with sepsis or acute respiratory distress syndrome (ARDS) generate heterogeneous trial populations. Non-random variation in the treatment effect of an intervention due to differences in the baseline risk of death between patients in a population represents one form of heterogeneity of treatment effect (HTE). We assessed whether HTE in two sepsis and one ARDS RCTs could explain indeterminate trial results and inform future trial design. METHODS: We assessed HTE for vasopressin, hydrocortisone and levosimendan in sepsis and simvastatin in ARDS patients, on 28-day mortality, using the total Acute Physiology And Chronic Health Evaluation II (APACHE II) score as the baseline risk measurement, comparing above (high) and below (low) the median score. Secondary risk measures were the acute physiology component of APACHE II and predicted risk of mortality using the APACHE II score. HTE was quantified both in additive (difference in risk difference (RD)) and multiplicative (ratio of relative risks (RR)) scales using estimated treatment differences from a logistic regression model with treatment risk as the interaction term. RESULTS: The ratio of the odds of death in the highest APACHE II quartile was 4.9 to 7.4 times compared to the lowest quartile, across the three trials. We did not observe HTE for vasopressin, hydrocortisone and levosimendan in the two sepsis trials. In the HARP-2 trial, simvastatin reduced mortality in the low APACHE II group and increased mortality in the high APACHE II group (difference in RD = 0.34 (0.12, 0.55) (p = 0.02); ratio of RR 3.57 (1.77, 7.17) (p < 0.001). The HTE patterns were inconsistent across the secondary risk measures. The sensitivity analyses of HTE effects for vasopressin, hydrocortisone and levosimendan were consistent with the main analyses and attenuated for simvastatin. CONCLUSIONS: We assessed HTE in three recent ICU RCTs, using multivariable baseline risk of death models. There was considerable within-trial variation in the baseline risk of death. We observed potential HTE for simvastatin in ARDS, but no evidence of HTE for vasopressin, hydrocortisone or levosimendan in the two sepsis trials. Our findings could be explained either by true lack of HTE (no benefit of vasopressin, hydrocortisone or levosimendan vs comparator for any patient subgroups) or by lack of power to detect HTE. Our results require validation using similar trial databases.


Asunto(s)
Enfermedad Crítica/terapia , Adhesión a Directriz/tendencias , Síndrome de Dificultad Respiratoria/tratamiento farmacológico , Sepsis/tratamiento farmacológico , Resultado del Tratamiento , APACHE , Adulto , Anciano , Antiinflamatorios/uso terapéutico , Cardiotónicos/uso terapéutico , Enfermedad Crítica/mortalidad , Femenino , Mortalidad Hospitalaria/tendencias , Humanos , Hidrocortisona/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Unidades de Cuidados Intensivos/organización & administración , Unidades de Cuidados Intensivos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Síndrome de Dificultad Respiratoria/mortalidad , Sepsis/mortalidad , Simendán/uso terapéutico , Simvastatina/uso terapéutico , Vasoconstrictores/uso terapéutico , Vasopresinas/uso terapéutico
12.
Lancet ; 389(10085): 2193-2203, 2017 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-28494920

RESUMEN

BACKGROUND: Proliferative diabetic retinopathy is the most common cause of severe sight impairment in people with diabetes. Proliferative diabetic retinopathy has been managed by panretinal laser photocoagulation (PRP) for the past 40 years. We report the 1 year safety and efficacy of intravitreal aflibercept. METHODS: In this phase 2b, single-blind, non-inferiority trial (CLARITY), adults (aged ≥18 years) with type 1 or 2 diabetes and previously untreated or post-laser treated active proliferative diabetic retinopathy were recruited from 22 UK ophthalmic centres. Patients were randomly assigned (1:1) to repeated intravitreal aflibercept (2 mg/0·05 mL at baseline, 4 weeks, and 8 weeks, and from week 12 patients were reviewed every 4 weeks and aflibercept injections were given as needed) or PRP standard care (single spot or mutlispot laser at baseline, fractionated fortnightly thereafter, and from week 12 patients were assessed every 8 weeks and treated with PRP as needed) for 52 weeks. Randomisation was by minimisation with a web-based computer generated system. Primary outcome assessors were masked optometrists. The treating ophthalmologists and participants were not masked. The primary outcome was defined as a change in best-corrected visual acuity at 52 weeks with a linear mixed-effect model that estimated adjusted treatment effects at both 12 weeks and 52 weeks, having excluded fluctuations in best corrected visual acuity owing to vitreous haemorrhage. This modified intention-to-treat analysis was reapplied to the per protocol participants. The non-inferiority margin was prespecified as -5 Early Treatment Diabetic Retinopathy Study letters. Safety was assessed in all participants. This trial is registered with ISRCTN registry, number 32207582. FINDINGS: We recruited 232 participants (116 per group) between Aug 22, 2014 and Nov 30, 2015. 221 participants (112 in aflibercept group, 109 in PRP group) contributed to the modified intention-to-treat model, and 210 participants (104 in aflibercept group and 106 in PRP group) within per protocol. Aflibercept was non-inferior and superior to PRP in both the modified intention-to-treat population (mean best corrected visual acuity difference 3·9 letters [95% CI 2·3-5·6], p<0·0001) and the per-protocol population (4·0 letters [2·4-5·7], p<0·0001). There were no safety concerns. The 95% CI adjusted difference between groups was more than the prespecified acceptable margin of -5 letters at both 12 weeks and 52 weeks. INTERPRETATION: Patients with proliferative diabetic retinopathy who were treated with intravitreal aflibercept had an improved outcome at 1 year compared with those treated with PRP standard care. FUNDING: The Efficacy and Mechanism Evaluation Programme, a Medical Research Council and National Institute for Health Research partnership.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Retinopatía Diabética/terapia , Coagulación con Láser/métodos , Receptores de Factores de Crecimiento Endotelial Vascular/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Adulto , Anciano , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/efectos adversos , Retinopatía Diabética/fisiopatología , Femenino , Humanos , Inyecciones Intravítreas , Coagulación con Láser/efectos adversos , Masculino , Persona de Mediana Edad , Receptores de Factores de Crecimiento Endotelial Vascular/administración & dosificación , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/efectos adversos , Sensibilidad y Especificidad , Método Simple Ciego , Resultado del Tratamiento , Agudeza Visual/efectos de los fármacos
13.
Cochrane Database Syst Rev ; 2: CD009315, 2018 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-29482264

RESUMEN

BACKGROUND: Nutritional labelling is advocated as a means to promote healthier food purchasing and consumption, including lower energy intake. Internationally, many different nutritional labelling schemes have been introduced. There is no consensus on whether such labelling is effective in promoting healthier behaviour. OBJECTIVES: To assess the impact of nutritional labelling for food and non-alcoholic drinks on purchasing and consumption of healthier items. Our secondary objective was to explore possible effect moderators of nutritional labelling on purchasing and consumption. SEARCH METHODS: We searched 13 electronic databases including CENTRAL, MEDLINE and Embase to 26 April 2017. We also handsearched references and citations and sought unpublished studies through websites and trials registries. SELECTION CRITERIA: Eligible studies: were randomised or quasi-randomised controlled trials (RCTs/Q-RCTs), controlled before-and-after studies, or interrupted time series (ITS) studies; compared a labelled product (with information on nutrients or energy) with the same product without a nutritional label; assessed objectively measured purchasing or consumption of foods or non-alcoholic drinks in real-world or laboratory settings. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies for inclusion and extracted study data. We applied the Cochrane 'Risk of bias' tool and GRADE to assess the quality of evidence. We pooled studies that evaluated similar interventions and outcomes using a random-effects meta-analysis, and we synthesised data from other studies in a narrative summary. MAIN RESULTS: We included 28 studies, comprising 17 RCTs, 5 Q-RCTs and 6 ITS studies. Most (21/28) took place in the USA, and 19 took place in university settings, 14 of which mainly involved university students or staff. Most (20/28) studies assessed the impact of labelling on menus or menu boards, or nutritional labelling placed on, or adjacent to, a range of foods or drinks from which participants could choose. Eight studies provided participants with only one labelled food or drink option (in which labelling was present on a container or packaging, adjacent to the food or on a display board) and measured the amount consumed. The most frequently assessed labelling type was energy (i.e. calorie) information (12/28).Eleven studies assessed the impact of nutritional labelling on purchasing food or drink options in real-world settings, including purchases from vending machines (one cluster-RCT), grocery stores (one ITS), or restaurants, cafeterias or coffee shops (three RCTs, one Q-RCT and five ITS). Findings on vending machines and grocery stores were not interpretable, and were rated as very low quality. A meta-analysis of the three RCTs, all of which assessed energy labelling on menus in restaurants, demonstrated a statistically significant reduction of 47 kcal in energy purchased (MD -46.72 kcal, 95% CI -78.35, -15.10, N = 1877). Assuming an average meal of 600 kcal, energy labelling on menus would reduce energy purchased per meal by 7.8% (95% CI 2.5% to 13.1%). The quality of the evidence for these three studies was rated as low, so our confidence in the effect estimate is limited and may change with further studies. Of the remaining six studies, only two (both ITS studies involving energy labels on menus or menus boards in a coffee shop or cafeteria) were at low risk of bias, and their results support the meta-analysis. The results of the other four studies which were conducted in a restaurant, cafeterias (2 studies) or a coffee shop, were not clearly reported and were at high risk of bias.Seventeen studies assessed the impact of nutritional labels on consumption in artificial settings or scenarios (henceforth referred to as laboratory studies or settings). Of these, eight (all RCTs) assessed the effect of labels on menus or placed on a range of food options. A meta-analysis of these studies did not conclusively demonstrate a reduction in energy consumed during a meal (MD -50 kcal, 95% CI -104.41, 3.88, N = 1705). We rated the quality of the evidence as low, so our confidence in the effect estimate is limited and may change with further studies.Six laboratory studies (four RCTs and two Q-RCTs) assessed the impact of labelling a single food or drink option (such as chocolate, pasta or soft drinks) on energy consumed during a snack or meal. A meta-analysis of these studies did not demonstrate a statistically significant difference in energy (kcal) consumed (SMD 0.05, 95% CI -0.17 to 0.27, N = 732). However, the confidence intervals were wide, suggesting uncertainty in the true effect size. We rated the quality of the evidence as low, so our confidence in the effect estimate is limited and may change with further studies.There was no evidence that nutritional labelling had the unintended harm of increasing energy purchased or consumed. Indirect evidence came from five laboratory studies that involved mislabelling single nutrient content (i.e. placing low energy or low fat labels on high-energy foods) during a snack or meal. A meta-analysis of these studies did not demonstrate a statistically significant increase in energy (kcal) consumed (SMD 0.19, 95% CI -0.14to 0.51, N = 718). The effect was small and the confidence intervals wide, suggesting uncertainty in the true effect size. We rated the quality of the evidence from these studies as very low, providing very little confidence in the effect estimate. AUTHORS' CONCLUSIONS: Findings from a small body of low-quality evidence suggest that nutritional labelling comprising energy information on menus may reduce energy purchased in restaurants. The evidence assessing the impact on consumption of energy information on menus or on a range of food options in laboratory settings suggests a similar effect to that observed for purchasing, although the evidence is less definite and also of low quality.Accordingly, and in the absence of observed harms, we tentatively suggest that nutritional labelling on menus in restaurants could be used as part of a wider set of measures to tackle obesity. Additional high-quality research in real-world settings is needed to enable more certain conclusions.Further high-quality research is also needed to address the dearth of evidence from grocery stores and vending machines and to assess potential moderators of the intervention effect, including socioeconomic status.


Asunto(s)
Bebidas , Comercio , Ingestión de Energía , Etiquetado de Alimentos , Alimentos/normas , Ingesta Diaria Recomendada , Distribuidores Automáticos de Alimentos , Humanos , Análisis de Series de Tiempo Interrumpido , Laboratorios , Ensayos Clínicos Controlados no Aleatorios como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Restaurantes
14.
Biostatistics ; 17(4): 634-49, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26993061

RESUMEN

The problem of selection bias has long been recognized in the analysis of two-stage trials, where promising candidates are selected in stage 1 for confirmatory analysis in stage 2. To efficiently correct for bias, uniformly minimum variance conditionally unbiased estimators (UMVCUEs) have been proposed for a wide variety of trial settings, but where the population parameter estimates are assumed to be independent. We relax this assumption and derive the UMVCUE in the multivariate normal setting with an arbitrary known covariance structure. One area of application is the estimation of odds ratios (ORs) when combining a genome-wide scan with a replication study. Our framework explicitly accounts for correlated single nucleotide polymorphisms, as might occur due to linkage disequilibrium. We illustrate our approach on the measurement of the association between 11 genetic variants and the risk of Crohn's disease, as reported in Parkes and others (2007. Sequence variants in the autophagy gene IRGM and multiple other replicating loci contribute to Crohn's disease susceptibility. Nat. Gen. 39: (7), 830-832.), and show that the estimated ORs can vary substantially if both selection and correlation are taken into account.


Asunto(s)
Estudio de Asociación del Genoma Completo/normas , Polimorfismo de Nucleótido Simple , Sesgo de Selección , Enfermedad de Crohn/genética , Humanos
15.
Stat Med ; 35(22): 3907-22, 2016 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-27103068

RESUMEN

Seamless phase II/III clinical trials offer an efficient way to select an experimental treatment and perform confirmatory analysis within a single trial. However, combining the data from both stages in the final analysis can induce bias into the estimates of treatment effects. Methods for bias adjustment developed thus far have made restrictive assumptions about the design and selection rules followed. In order to address these shortcomings, we apply recent methodological advances to derive the uniformly minimum variance conditionally unbiased estimator for two-stage seamless phase II/III trials. Our framework allows for the precision of the treatment arm estimates to take arbitrary values, can be utilised for all treatments that are taken forward to phase III and is applicable when the decision to select or drop treatment arms is driven by a multiplicity-adjusted hypothesis testing procedure. © 2016 The Authors. Statistics in Medicine Published by John Wiley & Sons Ltd.


Asunto(s)
Ensayos Clínicos Fase II como Asunto , Ensayos Clínicos Fase III como Asunto , Proyectos de Investigación , Sesgo , Biometría , Humanos
16.
BMC Public Health ; 16(1): 1033, 2016 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-27716297

RESUMEN

BACKGROUND: Very brief interventions (VBIs) for physical activity are promising, but there is uncertainty about their potential effectiveness and cost. We assessed potential efficacy, feasibility, acceptability, and cost of three VBIs in primary care, in order to select the most promising intervention for evaluation in a subsequent large-scale RCT. METHODS: Three hundred and ninety four adults aged 40-74 years were randomised to a Motivational (n = 83), Pedometer (n = 74), or Combined (n = 80) intervention, delivered immediately after a preventative health check in primary care, or control (Health Check only; n = 157). Potential efficacy was measured as the probability of a positive difference between an intervention arm and the control arm in mean physical activity, measured by accelerometry at 4 weeks. RESULTS: For the primary outcome the estimated effect sizes (95 % CI) relative to the Control arm for the Motivational, Pedometer and Combined arms were respectively: +20.3 (-45.0, +85.7), +23.5 (-51.3, +98.3), and -3.1 (-69.3, +63.1) counts per minute. There was a73% probability of a positive effect on physical activity for each of the Motivational and Pedometer VBIs relative to control, but only 46 % for the Combined VBI. Only the Pedometer VBI was deliverable within 5 min. All VBIs were acceptable and low cost. CONCLUSIONS: Based on the four criteria, the Pedometer VBI was selected for evaluation in a large-scale trial. TRIAL REGISTRATION: Current Controlled Trials ISRCTN02863077 . Retrospectively registered 05/10/2012.


Asunto(s)
Ejercicio Físico , Conductas Relacionadas con la Salud , Promoción de la Salud/métodos , Atención Primaria de Salud , Actigrafía , Adulto , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Motivación , Resultado del Tratamiento
17.
Am J Public Health ; 105(9): e54-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26180980

RESUMEN

OBJECTIVES: We examined the probability of an obese person attaining normal body weight. METHODS: We drew a sample of individuals aged 20 years and older from the United Kingdom's Clinical Practice Research Datalink from 2004 to 2014. We analyzed data for 76,704 obese men and 99,791 obese women. We excluded participants who received bariatric surgery. We estimated the probability of attaining normal weight or 5% reduction in body weight. RESULTS: During a maximum of 9 years' follow-up, 1283 men and 2245 women attained normal body weight. In simple obesity (body mass index = 30.0-34.9 kg/m(2)), the annual probability of attaining normal weight was 1 in 210 for men and 1 in 124 for women, increasing to 1 in 1290 for men and 1 in 677 for women with morbid obesity (body mass index = 40.0-44.9 kg/m(2)). The annual probability of achieving a 5% weight reduction was 1 in 8 for men and 1 in 7 for women with morbid obesity. CONCLUSIONS: The probability of attaining normal weight or maintaining weight loss is low. Obesity treatment frameworks grounded in community-based weight management programs may be ineffective.


Asunto(s)
Peso Corporal Ideal , Obesidad/fisiopatología , Pérdida de Peso , Adulto , Anciano , Índice de Masa Corporal , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/fisiopatología , Probabilidad , Reino Unido
18.
Stat Med ; 34(8): 1417-37, 2015 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-25645331

RESUMEN

When developing a new diagnostic test for a disease, there are often multiple candidate classifiers to choose from, and it is unclear if any will offer an improvement in performance compared with current technology. A two-stage design can be used to select a promising classifier (if one exists) in stage one for definitive validation in stage two. However, estimating the true properties of the chosen classifier is complicated by the first stage selection rules. In particular, the usual maximum likelihood estimator (MLE) that combines data from both stages will be biased high. Consequently, confidence intervals and p-values flowing from the MLE will also be incorrect. Building on the results of Pepe et al. (SIM 28:762-779), we derive the most efficient conditionally unbiased estimator and exact confidence intervals for a classifier's sensitivity in a two-stage design with arbitrary selection rules; the condition being that the trial proceeds to the validation stage. We apply our estimation strategy to data from a recent family history screening tool validation study by Walter et al. (BJGP 63:393-400) and are able to identify and successfully adjust for bias in the tool's estimated sensitivity to detect those at higher risk of breast cancer.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Detección Precoz del Cáncer/normas , Diseño de Investigaciones Epidemiológicas , Salud de la Familia/estadística & datos numéricos , Análisis de Varianza , Sesgo , Biomarcadores/análisis , Simulación por Computador , Intervalos de Confianza , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/estadística & datos numéricos , Femenino , Humanos , Funciones de Verosimilitud , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Medición de Riesgo/normas , Medición de Riesgo/estadística & datos numéricos , Estadísticas no Paramétricas , Encuestas y Cuestionarios/normas
19.
Ann Behav Med ; 49(1): 7-17, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24806469

RESUMEN

BACKGROUND: Meta-analyses have identified promising behavior change techniques (BCTs) in changing obesity-related behaviors from intervention descriptions. However, it is unclear whether these BCTs are used by intervention participants and are related to outcomes. PURPOSE: The purpose of this study is to investigate BCT use by participants of an intervention targeting physical activity and diet and whether BCT use was related to behavior change and weight loss. METHODS: Intervention participants (N = 239; 40-69 years) with recently diagnosed type 2 diabetes in the ADDITION-Plus trial received a theory-based intervention which taught them a range of BCTs. BCT usage was reported at 1 year. RESULTS: Thirty-six percent of the participants reported using all 16 intervention BCTs. Use of a higher number of BCTs and specific BCTs (e.g., goal setting) were associated with a reduction in body mass index (BMI). CONCLUSIONS: BCT use was associated with weight loss. Future research should identify strategies to promote BCT use in daily life. ( TRIAL REGISTRATION: ISRCTN99175498.).


Asunto(s)
Terapia Conductista/métodos , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/rehabilitación , Dieta , Conductas Relacionadas con la Salud , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
20.
Soft Matter ; 11(5): 871-81, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25514137

RESUMEN

We report on normal contact and friction measurements of model multicontact interfaces formed between smooth surfaces and substrates textured with a statistical distribution of spherical micro-asperities. Contacts are either formed between a rigid textured lens and a smooth rubber, or a flat textured rubber and a smooth rigid lens. Measurements of the real area of contact A versus normal load P are performed by imaging the light transmitted at the microcontacts. For both interfaces, A(P) is found to be sub-linear with a power law behavior. Comparison with two multi-asperity contact models, which extend the Greenwood-Williamson (J. Greenwood and J. Williamson, Proc. Royal Soc. London Ser. A, 295, 300 (1966)) model by taking into account the elastic interaction between asperities at different length scales, is performed, and allows their validation for the first time. We find that long range elastic interactions arising from the curvature of the nominal surfaces are the main source of the non-linearity of A(P). At a shorter range, and except for very low pressures, the pressure dependence of both density and area of microcontacts remains well described by Greenwood-Williamson's model, which neglects any interaction between asperities. In addition, in steady sliding, friction measurements reveal that the mean shear stress at the scale of the asperities is systematically larger than that found for a macroscopic contact between a smooth lens and a rubber. This suggests that frictional stresses measured at macroscopic length scales may not be simply transposed to microscopic multicontact interfaces.

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