RESUMO
Animals actively sample their environment through orienting actions such as saccadic eye movements. Saccadic targets are selected based both on sensory evidence immediately preceding the saccade, and a "salience map" or prior built-up over multiple saccades. In the primate cortex, the selection of each individual saccade depends on competition between target-selective cells that ramp up their firing rate to saccade release. However, it is less clear how a cross-saccade prior might be implemented, either in neural firing or through an activity-silent mechanism such as modification of synaptic weights on sensory inputs. Here, we present evidence from magnetoencephalography for 2 distinct processes underlying the selection of the current saccade, and the representation of the prior, in human parietal cortex. While the classic ramping decision process for each saccade was reflected in neural firing rates (measured in the event-related field), a prior built-up over multiple saccades was implemented via modulation of the gain on sensory inputs from the preferred target, as evidenced by rapid frequency tagging. A cascade of computations over time (initial representation of the prior, followed by evidence accumulation and then an integration of prior and evidence) provides a mechanism by which a salience map may be built up across saccades in parietal cortex. It also provides insight into the apparent contradiction that inactivation of parietal cortex has been shown not to affect performance on single-trials, despite the presence of clear evidence accumulation signals in this region.
Assuntos
Lobo Parietal , Movimentos Sacádicos , Animais , Humanos , Lobo Parietal/fisiologia , Estimulação LuminosaRESUMO
The ongoing reproducibility crisis in psychology and cognitive neuroscience has sparked increasing calls to re-evaluate and reshape scientific culture and practices. Heeding those calls, we have recently launched the EEGManyPipelines project as a means to assess the robustness of EEG research in naturalistic conditions and experiment with an alternative model of conducting scientific research. One hundred sixty-eight analyst teams, encompassing 396 individual researchers from 37 countries, independently analyzed the same unpublished, representative EEG data set to test the same set of predefined hypotheses and then provided their analysis pipelines and reported outcomes. Here, we lay out how large-scale scientific projects can be set up in a grassroots, community-driven manner without a central organizing laboratory. We explain our recruitment strategy, our guidance for analysts, the eventual outputs of this project, and how it might have a lasting impact on the field.
Assuntos
Eletroencefalografia , Projetos de Pesquisa , Humanos , Reprodutibilidade dos TestesRESUMO
Frequency tagging has been successfully used to investigate selective stimulus processing in electroencephalography (EEG) or magnetoencephalography (MEG) studies. Recently, new projectors have been developed that allow for frequency tagging at higher frequencies (>60 Hz). This technique, rapid invisible frequency tagging (RIFT), provides two crucial advantages over low-frequency tagging as (i) it leaves low-frequency oscillations unperturbed, and thus open for investigation, and ii) it can render the tagging invisible, resulting in more naturalistic paradigms and a lack of participant awareness. The development of this technique has far-reaching implications as oscillations involved in cognitive processes can be investigated, and potentially manipulated, in a more naturalistic manner.
Assuntos
Eletroencefalografia , Magnetoencefalografia , Humanos , Eletroencefalografia/métodos , Magnetoencefalografia/métodos , CogniçãoRESUMO
BACKGROUND: Multimorbidity, characterised by the coexistence of multiple chronic conditions in an individual, is a rising public health concern. While much of the existing research has focused on cross-sectional patterns of multimorbidity, there remains a need to better understand the longitudinal accumulation of diseases. This includes examining the associations between important sociodemographic characteristics and the rate of progression of chronic conditions. METHODS AND FINDINGS: We utilised electronic primary care records from 13.48 million participants in England, drawn from the Clinical Practice Research Datalink (CPRD Aurum), spanning from 2005 to 2020 with a median follow-up of 4.71 years (IQR: 1.78, 11.28). The study focused on 5 important chronic conditions: cardiovascular disease (CVD), type 2 diabetes (T2D), chronic kidney disease (CKD), heart failure (HF), and mental health (MH) conditions. Key sociodemographic characteristics considered include ethnicity, social and material deprivation, gender, and age. We employed a flexible spline-based parametric multistate model to investigate the associations between these sociodemographic characteristics and the rate of different disease transitions throughout multimorbidity development. Our findings reveal distinct association patterns across different disease transition types. Deprivation, gender, and age generally demonstrated stronger associations with disease diagnosis compared to ethnic group differences. Notably, the impact of these factors tended to attenuate with an increase in the number of preexisting conditions, especially for deprivation, gender, and age. For example, the hazard ratio (HR) (95% CI; p-value) for the association of deprivation with T2D diagnosis (comparing the most deprived quintile to the least deprived) is 1.76 ([1.74, 1.78]; p < 0.001) for those with no preexisting conditions and decreases to 0.95 ([0.75, 1.21]; p = 0.69) with 4 preexisting conditions. Furthermore, the impact of deprivation, gender, and age was typically more pronounced when transitioning from an MH condition. For instance, the HR (95% CI; p-value) for the association of deprivation with T2D diagnosis when transitioning from MH is 2.03 ([1.95, 2.12], p < 0.001), compared to transitions from CVD 1.50 ([1.43, 1.58], p < 0.001), CKD 1.37 ([1.30, 1.44], p < 0.001), and HF 1.55 ([1.34, 1.79], p < 0.001). A primary limitation of our study is that potential diagnostic inaccuracies in primary care records, such as underdiagnosis, overdiagnosis, or ascertainment bias of chronic conditions, could influence our results. CONCLUSIONS: Our results indicate that early phases of multimorbidity development could warrant increased attention. The potential importance of earlier detection and intervention of chronic conditions is underscored, particularly for MH conditions and higher-risk populations. These insights may have important implications for the management of multimorbidity.
Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Insuficiência Renal Crônica , Humanos , Multimorbidade , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Estudos Transversais , Inglaterra/epidemiologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Doença Crônica , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Atenção Primária à SaúdeRESUMO
BACKGROUND: Primary care electronic health records (EHR) are widely used to study long-term conditions in epidemiological and health services research. Therefore, it is important to understand how well the recorded prevalence of these conditions in EHRs, compares to other reliable sources overall, and varies by socio-demographic characteristics. We aimed to describe the prevalence and socio-demographic variation of cardiovascular, renal, and metabolic (CRM) and mental health (MH) conditions in a large, nationally representative, English primary care database and compare with prevalence estimates from other population-based studies. METHODS: This was a cross-sectional study using the Clinical Practice Research Datalink (CPRD) Aurum primary care database. We calculated prevalence of 18 conditions and used logistic regression to assess how this varied by age, sex, ethnicity, and socio-economic status. We searched the literature for population prevalence estimates from other sources for comparison with the prevalences in CPRD Aurum. RESULTS: Depression (16.0%, 95%CI 16.0-16.0%) and hypertension (15.3%, 95%CI 15.2-15.3%) were the most prevalent conditions among 12.4 million patients. Prevalence of most conditions increased with socio-economic deprivation and age. CRM conditions, schizophrenia and substance misuse were higher in men, whilst anxiety, depression, bipolar and eating disorders were more common in women. Cardiovascular risk factors (hypertension and diabetes) were more prevalent in black and Asian patients compared with white, but the trends in prevalence of cardiovascular diseases by ethnicity were more variable. The recorded prevalences of mental health conditions were typically twice as high in white patients compared with other ethnic groups. However, PTSD and schizophrenia were more prevalent in black patients. The prevalence of most conditions was similar or higher in the primary care database than diagnosed disease prevalence reported in national health surveys. However, screening studies typically reported higher prevalence estimates than primary care data, especially for PTSD, bipolar disorder and eating disorders. CONCLUSIONS: The prevalence of many clinically diagnosed conditions in primary care records closely matched that of other sources. However, we found important variations by sex and ethnicity, which may reflect true variation in prevalence or systematic differences in clinical presentation and practice. Primary care data may underrepresent the prevalence of undiagnosed conditions, particularly in mental health.
Assuntos
Hipertensão , Saúde Mental , Masculino , Humanos , Feminino , Prevalência , Estudos Transversais , Atenção Primária à SaúdeRESUMO
AIMS: Individuals with non-alcoholic steatohepatitis or elevated liver enzymes have increased cardiovascular mortality but are often excluded from prevention trials. We investigated the effectiveness of fixed-dose combination therapy for the prevention of major cardiovascular events (MCVE) among individuals with and without presumed non-alcoholic steatohepatitis (pNASH). METHODS AND RESULTS: Two thousand four hundred participants over 50 were randomized into the intervention and control groups. Consent was obtained post-randomization. Consenting participants in the intervention group were given a pill containing aspirin, atorvastatin, hydrochlorothiazide, and valsartan (polypill). Participants were followed for 5 years. Presumed non-alcoholic steatohepatitis was diagnosed by ultrasonography and elevated liver enzymes. The primary outcome was MCVE. ClinicalTrials.gov: NCT01245608. Among the originally randomized population, 138 of 1249 in the intervention group (11.0%) and 137 of 1017 controls (13.5%) had MCVE during the 5-year follow-up [unadjusted risk ratio (RR) 0.83, 95% confidence interval (CI) 0.66-1.03]. Of the 1508 participants who consented to additional measurements and treatment, 63 of 787 (8.0%) intervention group participants and 86 of 721 (11.9%) controls had MCVE (adjusted RR 0.61, 95% CI 0.44-0.83). Although the adjusted relative risk of MCVE in participants with pNASH (0.35, 95% CI 0.17-0.74) was under half that for participants without pNASH (0.73, 95% CI 0.49-1.00), the difference did not reach statistical significance. There was no change in liver enzymes in participants taking polypill but among those with pNASH, there was a significant decrease after 60 months of follow-up (intragroup -12.0 IU/L, 95% CI -14.2 to -9.6). CONCLUSION: Among patients consenting to receive fixed-dose combination therapy, polypill is safe and effective for the prevention of MCVE, even among participants with fatty liver and increased liver enzymes.
Assuntos
Doenças Cardiovasculares , Hepatopatia Gordurosa não Alcoólica , Anti-Hipertensivos/uso terapêutico , Combinação de Medicamentos , Humanos , Hidroclorotiazida/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/complicaçõesRESUMO
BACKGROUND: Severe mental illness (SMI; schizophrenia, bipolar disorders (BDs), and other nonorganic psychoses) is associated with increased risk of cardiovascular disease (CVD) and CVD-related mortality. To date, no systematic review has investigated changes in population level CVD-related mortality over calendar time. It is unclear if this relationship has changed over time in higher-income countries with changing treatments. METHODS AND FINDINGS: To address this gap, a systematic review was conducted, to assess the association between SMI and CVD including temporal change. Seven databases were searched (last: November 30, 2021) for cohort or case-control studies lasting ≥1 year, comparing frequency of CVD mortality or incidence in high-income countries between people with versus without SMI. No language restrictions were applied. Random effects meta-analyses were conducted to compute pooled hazard ratios (HRs) and rate ratios, pooled standardised mortality ratios (SMRs), pooled odds ratios (ORs), and pooled risk ratios (RRs) of CVD in those with versus without SMI. Temporal trends were explored by decade. Subgroup analyses by age, sex, setting, world region, and study quality (Newcastle-Ottawa scale (NOS) score) were conducted. The narrative synthesis included 108 studies, and the quantitative synthesis 59 mortality studies (with (≥1,841,356 cases and 29,321,409 controls) and 28 incidence studies (≥401,909 cases and 14,372,146 controls). The risk of CVD-related mortality for people with SMI was higher than controls across most comparisons, except for total CVD-related mortality for BD and cerebrovascular accident (CVA) for mixed SMI. Estimated risks were larger for schizophrenia than BD. Pooled results ranged from SMR = 1.55 (95% confidence interval (CI): 1.33 to 1.81, p < 0.001), for CVA in people with BD to HR/rate ratio = 2.40 (95% CI: 2.25 to 2.55, p < 0.001) for CVA in schizophrenia. For schizophrenia and BD, SMRs and pooled HRs/rate ratios for CHD and CVD mortality were larger in studies with outcomes occurring during the 1990s and 2000s than earlier decades (1980s: SMR = 1.14, 95% CI: 0.57 to 2.30, p = 0.71; 2000s: SMR = 2.59, 95% CI: 1.93 to 3.47, p < 0.001 for schizophrenia and CHD) and in studies including people with younger age. The incidence of CVA, CVD events, and heart failure in SMI was higher than controls. Estimated risks for schizophrenia ranged from HR/rate ratio 1.25 (95% CI: 1.04 to 1.51, p = 0.016) for total CVD events to rate ratio 3.82 (95% CI: 3.1 to 4.71, p < 0.001) for heart failure. Incidence of CHD was higher in BD versus controls. However, for schizophrenia, CHD was elevated in higher-quality studies only. The HR/rate ratios for CVA and CHD were larger in studies with outcomes occurring after the 1990s. Study limitations include the high risk of bias of some studies as they drew a comparison cohort from general population rates and the fact that it was difficult to exclude studies that had overlapping populations, although attempts were made to minimise this. CONCLUSIONS: In this study, we found that SMI was associated with an approximate doubling in the rate ratio of CVD-related mortality, particularly since the 1990s, and in younger groups. SMI was also associated with increased incidence of CVA and CHD relative to control participants since the 1990s. More research is needed to clarify the association between SMI and CHD and ways to mitigate this risk.
Assuntos
Doenças Cardiovasculares , Insuficiência Cardíaca , Transtornos Mentais , Transtornos Psicóticos , Esquizofrenia , Doenças Cardiovasculares/epidemiologia , Humanos , Transtornos Mentais/complicações , Transtornos Mentais/epidemiologia , Esquizofrenia/complicações , Esquizofrenia/epidemiologiaRESUMO
Sustained attention has long been thought to benefit perception in a continuous fashion, but recent evidence suggests that it affects perception in a discrete, rhythmic way. Periodic fluctuations in behavioral performance over time, and modulations of behavioral performance by the phase of spontaneous oscillatory brain activity point to an attentional sampling rate in the theta or alpha frequency range. We investigated whether such discrete sampling by attention is reflected in periodic fluctuations in the decodability of visual stimulus orientation from magnetoencephalographic (MEG) brain signals. In this exploratory study, human subjects attended one of the two grating stimuli, while MEG was being recorded. We assessed the strength of the visual representation of the attended stimulus using a support vector machine (SVM) to decode the orientation of the grating (clockwise vs. counterclockwise) from the MEG signal. We tested whether decoder performance depended on the theta/alpha phase of local brain activity. While the phase of ongoing activity in the visual cortex did not modulate decoding performance, theta/alpha phase of activity in the frontal eye fields and parietal cortex, contralateral to the attended stimulus did modulate decoding performance. These findings suggest that phasic modulations of visual stimulus representations in the brain are caused by frequency-specific top-down activity in the frontoparietal attention network, though the behavioral relevance of these effects could not be established.
Assuntos
Córtex Visual , Percepção Visual , Humanos , Magnetoencefalografia , Lobo Parietal , Estimulação LuminosaRESUMO
BACKGROUND & AIMS: The epidemiology of autoimmune liver disease (AILD) is challenging to study because of the diseases' rarity and because of cohort selection bias. Increased incidence farther from the Equator has been reported for multiple sclerosis, another autoimmune disease. We assessed the incidence of primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and autoimmune hepatitis (AIH) in relation to latitude. METHODS: We performed a retrospective cohort study using anonymized UK primary care records from January 1, 2002, to May 10, 2016. All adults without a baseline diagnosis of AILD were included and followed up until the first occurrence of an AILD diagnosis, death, or they left the database. Latitude was measured as registered general practice rounded down to whole degrees. RESULTS: The cohort included 8,590,421 records with 53.3 × 107 years of follow-up evaluation from 694 practices. There were 1314 incident cases of PBC, 396 of PSC, and 1034 of AIH. Crude incidences were as follows: PBC, 2.47 (95% CI, 2.34-2.60); PSC, 0.74 (95% CI, 0.67-0.82); and AIH, 1.94 (95% CI, 1.83-2.06) per 100,000 per year. PBC incidence correlated with female sex, smoking, and deprivation; PSC incidence correlated with male sex and non-smoking; AIH incidence correlated with female sex and deprivation. A more northerly latitude was associated strongly with incidence of PBC: 2.16 (95% CI, 1.79-2.60) to 4.86 (95% CI, 3.93-6.00) from 50°N to 57°N (P = .002) and incidence of AIH: 2.00 (95% CI, 1.65-2.43) to 3.28 (95% CI, 2.53-4.24) (P = .003), but not incidence of PSC: 0.82 (95% CI, 0.60-1.11) to 1.02 (95% CI, 0.64-1.61) (P = .473). Incidence after adjustment for age, sex, smoking, and deprivation status showed similar positive correlations for PBC and AIH with latitude, but not PSC. Incident AIH cases were younger at more northerly latitude. CONCLUSIONS: We describe an association in the United Kingdom between more northerly latitude and the incidence of PBC and AIH that requires both confirmation and explanation.
Assuntos
Doenças Autoimunes , Colangite Esclerosante , Hepatite Autoimune , Cirrose Hepática Biliar , Hepatopatias , Adulto , Feminino , Hepatite Autoimune/epidemiologia , Humanos , Masculino , Estudos RetrospectivosRESUMO
Sodium-glucose co-transporter-2 (SGLT2) inhibitors are widely prescribed in people with type 2 diabetes. We aimed to investigate whether SGLT2 inhibitor prescription is associated with COVID-19, when compared with an active comparator. We performed a propensity-score-matched cohort study with active comparators and a negative control outcome in a large UK-based primary care dataset. Participants prescribed SGLT2 inhibitors (n = 9948) and a comparator group prescribed dipeptidyl peptidase-4 (DPP-4) inhibitors (n = 14 917) were followed up from January 30 to July 27, 2020. The primary outcome was confirmed or clinically suspected COVID-19. The incidence rate of COVID-19 was 19.7/1000 person-years among users of SGLT2 inhibitors and 24.7/1000 person-years among propensity-score-matched users of DPP-4 inhibitors. The adjusted hazard ratio was 0.92 (95% confidence interval 0.66 to 1.29), and there was no evidence of residual confounding in the negative control analysis. We did not observe an increased risk of COVID-19 in primary care amongst those prescribed SGLT2 inhibitors compared to DPP-4 inhibitors, suggesting that clinicians may safely use these agents in the everyday care of people with type 2 diabetes during the COVID-19 pandemic.
Assuntos
COVID-19/epidemiologia , Suscetibilidade a Doenças , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Idoso , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pontuação de Propensão , Estudos Retrospectivos , SARS-CoV-2 , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêuticoRESUMO
INTRODUCTION: Renin-angiotensin system (RAS) inhibitors have been postulated to influence susceptibility to Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). This study investigated whether there is an association between their prescription and the incidence of COVID-19 and all-cause mortality. METHODS: We conducted a propensity-score matched cohort study comparing the incidence of COVID-19 among patients with hypertension prescribed angiotensin-converting enzyme I (ACE) inhibitors or angiotensin II type-1 receptor blockers (ARBs) to those treated with calcium channel blockers (CCBs) in a large UK-based primary care database (The Health Improvement Network). We estimated crude incidence rates for confirmed/suspected COVID-19 in each drug exposure group. We used Cox proportional hazards models to produce adjusted hazard ratios for COVID-19. We assessed all-cause mortality as a secondary outcome. RESULTS: The incidence rate of COVID-19 among users of ACE inhibitors and CCBs was 9.3 per 1000 person-years (83 of 18,895 users [0.44%]) and 9.5 per 1000 person-years (85 of 18,895 [0.45%]), respectively. The adjusted hazard ratio was 0.92 (95% CI 0.68 to 1.26). The incidence rate among users of ARBs was 15.8 per 1000 person-years (79 out of 10,623 users [0.74%]). The adjusted hazard ratio was 1.38 (95% CI 0.98 to 1.95). There were no significant associations between use of RAS inhibitors and all-cause mortality. CONCLUSION: Use of ACE inhibitors was not associated with the risk of COVID-19 whereas use of ARBs was associated with a statistically non-significant increase compared to the use of CCBs. However, no significant associations were observed between prescription of either ACE inhibitors or ARBs and all-cause mortality.
Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anti-Hipertensivos/uso terapêutico , COVID-19/complicações , Bloqueadores dos Canais de Cálcio/uso terapêutico , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antagonistas de Receptores de Angiotensina/efeitos adversos , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Anti-Hipertensivos/efeitos adversos , COVID-19/mortalidade , Bloqueadores dos Canais de Cálcio/efeitos adversos , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mortalidade , Pontuação de Propensão , Modelos de Riscos Proporcionais , Sistema Renina-Angiotensina , Reino Unido , Adulto JovemRESUMO
Whereas subcortical structures such as the basal ganglia have been widely explored in relation to motor control, recent evidence suggests that their mechanisms extend to the domain of attentional switching. We here investigated the subcortical involvement in reward related top-down control of visual alpha-band oscillations (8-13 Hz), which have been consistently linked to mechanisms supporting the allocation of visuospatial attention. Given that items associated with contextual saliency (e.g., monetary reward or loss) attract attention, it is not surprising that the acquired salience of visual items further modulates. The executive networks controlling such reward-dependent modulations of oscillatory brain activity have yet to be fully elucidated. Although such networks have been explored in terms of corticocortical interactions, subcortical regions are likely to be involved. To uncover this, we combined MRI and MEG data from 17 male and 11 female participants, investigating whether derived measures of subcortical structural asymmetries predict interhemispheric modulation of alpha power during a spatial attention task. We show that volumetric hemispheric lateralization of globus pallidus (GP) and thalamus (Th) explains individual hemispheric biases in the ability to modulate posterior alpha power. Importantly, for the GP, this effect became stronger when the value saliency parings in the task increased. Our findings suggest that the GP and Th in humans are part of a subcortical executive control network, differentially involved in modulating posterior alpha activity in the presence of saliency. Further investigation aimed at uncovering the interaction between subcortical and neocortical attentional networks would provide useful insight in future studies.SIGNIFICANCE STATEMENT Whereas the involvement of subcortical regions into higher level cognitive processing, such as attention and reward attribution, has been already indicated in previous studies, little is known about its relationship with the functional oscillatory underpinnings of said processes. In particular, interhemispheric modulation of alpha band (8-13 Hz) oscillations, as recorded with magnetoencephalography, has been previously shown to vary as a function of salience (i.e., monetary reward/loss) in a spatial attention task. We here provide novel insights into the link between subcortical and cortical control of visual attention. Using the same reward-related spatial attention paradigm, we show that the volumetric lateralization of subcortical structures (specifically globus pallidus and thalamus) explains individual biases in the modulation of visual alpha activity.
Assuntos
Ritmo alfa , Atenção/fisiologia , Globo Pálido/fisiologia , Recompensa , Adulto , Percepção Auditiva/fisiologia , Condicionamento Clássico , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Magnetoencefalografia , Masculino , Percepção Visual/fisiologia , Adulto JovemRESUMO
BACKGROUND: A fixed-dose combination therapy (polypill strategy) has been proposed as an approach to reduce the burden of cardiovascular disease, especially in low-income and middle-income countries (LMICs). The PolyIran study aimed to assess the effectiveness and safety of a four-component polypill including aspirin, atorvastatin, hydrochlorothiazide, and either enalapril or valsartan for primary and secondary prevention of cardiovascular disease. METHODS: The PolyIran study was a two-group, pragmatic, cluster-randomised trial nested within the Golestan Cohort Study (GCS), a cohort study with 50â045 participants aged 40-75 years from the Golestan province in Iran. Clusters (villages) were randomly allocated (1:1) to either a package of non-pharmacological preventive interventions alone (minimal care group) or together with a once-daily polypill tablet (polypill group). Randomisation was stratified by three districts (Gonbad, Aq-Qala, and Kalaleh), with the village as the unit of randomisation. We used a balanced randomisation algorithm, considering block sizes of 20 and balancing for cluster size or natural log of the cluster size (depending on the skewness within strata). Randomisation was done at a fixed point in time (Jan 18, 2011) by statisticians at the University of Birmingham (Birmingham, UK), independent of the local study team. The non-pharmacological preventive interventions (including educational training about healthy lifestyle-eg, healthy diet with low salt, sugar, and fat content, exercise, weight control, and abstinence from smoking and opium) were delivered by the PolyIran field visit team at months 3 and 6, and then every 6 months thereafter. Two formulations of polypill tablet were used in this study. Participants were first prescribed polypill one (hydrochlorothiazide 12·5 mg, aspirin 81 mg, atorvastatin 20 mg, and enalapril 5 mg). Participants who developed cough during follow-up were switched by a trained study physician to polypill two, which included valsartan 40 mg instead of enalapril 5 mg. Participants were followed up for 60 months. The primary outcome-occurrence of major cardiovascular events (including hospitalisation for acute coronary syndrome, fatal myocardial infarction, sudden death, heart failure, coronary artery revascularisation procedures, and non-fatal and fatal stroke)-was centrally assessed by the GCS follow-up team, who were masked to allocation status. We did intention-to-treat analyses by including all participants who met eligibility criteria in the two study groups. The trial was registered with ClinicalTrials.gov, number NCT01271985. FINDINGS: Between Feb 22, 2011, and April 15, 2013, we enrolled 6838 individuals into the study-3417 (in 116 clusters) in the minimal care group and 3421 (in 120 clusters) in the polypill group. 1761 (51·5%) of 3421 participants in the polypill group were women, as were 1679 (49·1%) of 3417 participants in the minimal care group. Median adherence to polypill tablets was 80·5% (IQR 48·5-92·2). During follow-up, 301 (8·8%) of 3417 participants in the minimal care group had major cardiovascular events compared with 202 (5·9%) of 3421 participants in the polypill group (adjusted hazard ratio [HR] 0·66, 95% CI 0·55-0·80). We found no statistically significant interaction with the presence (HR 0·61, 95% CI 0·49-0·75) or absence of pre-existing cardiovascular disease (0·80; 0·51-1·12; pinteraction=0·19). When restricted to participants in the polypill group with high adherence, the reduction in the risk of major cardiovascular events was even greater compared with the minimal care group (adjusted HR 0·43, 95% CI 0·33-0·55). The frequency of adverse events was similar between the two study groups. 21 intracranial haemorrhages were reported during the 5 years of follow-up-ten participants in the polypill group and 11 participants in the minimal care group. There were 13 physician-confirmed diagnoses of upper gastrointestinal bleeding in the polypill group and nine in the minimal care group. INTERPRETATION: Use of polypill was effective in preventing major cardiovascular events. Medication adherence was high and adverse event numbers were low. The polypill strategy could be considered as an additional effective component in controlling cardiovascular diseases, especially in LMICs. FUNDING: Tehran University of Medical Sciences, Barakat Foundation, and Alborz Darou.
Assuntos
Fármacos Cardiovasculares/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Combinação de Medicamentos , Prevenção Secundária/métodos , Adulto , Idoso , Anticolesterolemiantes/administração & dosagem , Anti-Hipertensivos/administração & dosagem , Aspirina/administração & dosagem , Atorvastatina/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/epidemiologia , LDL-Colesterol/efeitos dos fármacos , Diabetes Mellitus/epidemiologia , Enalapril/administração & dosagem , Feminino , Humanos , Hidroclorotiazida/administração & dosagem , Masculino , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/administração & dosagem , Valsartana/administração & dosagemRESUMO
BACKGROUND: The database used for the NHS Bowel Cancer Screening Programme (BCSP) derives participant information from primary care records. Combining predictors with FOBTs has shown to improve referral decisions and accuracy. The richer data available from GP databases could be used to complement screening referral decisions by identifying those at greatest risk of colorectal cancer. We determined the availability of data for key predictors and whether this information could be used to inform more accurate screening referral decisions. METHODS: An English BCSP cohort was derived using the electronic notifications received from the BCSP database to GP records. The cohort covered a period between 13th May 2009 to 17th January 2017. Completeness of variables and univariable associations were assessed. Risk prediction models were developed using Cox regression and multivariable fractional polynomials with backwards elimination. Optimism adjusted performance metrics were reported. The sensitivity and specificity of a combined approach using the negative FOBT model plus FOBT positive patients was determined using a probability equivalent to a 3% PPV NICE guidelines level. RESULTS: 292,059 participants aged 60-74 were derived for the BCSP screening cohort. A model including the screening test result had a C-statistic of 0.860, c-slope of 0.997, and R2 of 0.597. A model developed for negative screening results only had a C-statistic of 0.597, c-slope of 0.940, and R2 of 0.062. Risk predictors included in the models included; age, sex, alcohol consumption, IBS diagnosis, family history of gastrointestinal cancer, smoking status, previous negatives and whether a GP had ordered a blood test. For the combined screening approach, sensitivity increased slightly from 53.90% (FOBT only) to 58.82% but at the expense of an increased referral rate. CONCLUSIONS: This research has identified several potential predictors for CRC in a BCSP population. A risk prediction model developed for BCSP FOBT negative patients was not clinically useful due to a low sensitivity and increased referral rate. The predictors identified in this study should be investigated in a refined algorithm combining the quantitative FIT result. Combining data from multiple sources enables fuller patient profiles using the primary care and screening database interface.
Assuntos
Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer , Registros Eletrônicos de Saúde , Modelos Estatísticos , Encaminhamento e Consulta , Fatores Etários , Idoso , Consumo de Bebidas Alcoólicas , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade , Fatores Sexuais , FumarRESUMO
Low frequency oscillations such as alpha (8-12 Hz) are hypothesized to rhythmically gate sensory processing, reflected by 40-100 Hz gamma band activity, via the mechanism of pulsed inhibition. We applied transcranial alternating current stimulation (TACS) at individual alpha frequency (IAF) and flanking frequencies (IAF-4 Hz, IAF+4 Hz) to the occipital cortex of healthy human volunteers during concurrent magnetoencephalography (MEG), while participants performed a visual detection task inducing strong gamma-band responses. Occipital (but not retinal) TACS phasically suppressed stimulus-induced gamma oscillations in the visual cortex and impaired target detection, with stronger phase-to-amplitude coupling predicting behavioral impairments. Retinal control TACS ruled out retino-thalamo-cortical entrainment resulting from (subthreshold) retinal stimulation. All TACS frequencies tested were effective, suggesting that visual gamma-band responses can be modulated by a range of low frequency oscillations. We propose that TACS-induced membrane potential modulations mimic the rhythmic change in cortical excitability by which spontaneous low frequency oscillations may eventually exert their impact when gating sensory processing via pulsed inhibition.
Assuntos
Ritmo Gama/fisiologia , Magnetoencefalografia , Estimulação Transcraniana por Corrente Contínua , Córtex Visual/fisiologia , Percepção Visual/fisiologia , Feminino , Humanos , Magnetoencefalografia/métodos , Masculino , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto JovemRESUMO
It is well known that attentional selection of relevant information relies on local synchronization of alpha band neuronal oscillations in visual cortices for inhibition of distracting inputs. Additionally, evidence for long-range coupling of neuronal oscillations between visual cortices and regions engaged in the anticipation of upcoming stimuli has been more recently provided. Nevertheless, on the one hand the relation between long-range functional coupling and anatomical connections is still to be assessed, and, on the other hand, the specific role of the alpha and beta frequency bands in the different processes underlying visuo-spatial attention still needs further clarification. We address these questions using measures of linear (frequency-specific) and nonlinear (cross-frequency) phase-synchronization in a cohort of 28 healthy subjects using magnetoencephalography. We show that alpha band phase-synchronization is modulated by the orienting of attention according to a parieto-occipital top-down mechanism reflecting behavior, and its hemispheric asymmetry is predicted by volume's asymmetry of specific tracts of the Superior-Longitudinal-Fasciculus. We also show that a network comprising parietal regions and the right putative Frontal-Eye-Field, but not the left, is recruited in the deployment of spatial attention through an alpha-beta cross-frequency coupling. Overall, we demonstrate that the visuospatial attention network features subsystems indexed by characteristic spectral fingerprints, playing different functional roles in the anticipation of upcoming stimuli and with diverse relation to fiber tracts.
Assuntos
Ritmo alfa/fisiologia , Atenção/fisiologia , Ritmo beta/fisiologia , Sincronização Cortical/fisiologia , Magnetoencefalografia/métodos , Rede Nervosa/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Substância Branca/fisiologia , Adulto , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Vias Neurais/fisiologia , Adulto JovemRESUMO
RATIONALE & OBJECTIVE: Chronic kidney disease (CKD) can substantially affect patients' health-related quality of life. Electronic patient-reported outcome measures (ePROMs) may capture symptoms and health-related quality of life and assist in the management of CKD. This study explored patient and clinician views on the use of a renal ePROM system. STUDY DESIGN: Qualitative study. SETTING & PARTICIPANTS: 12 patients with stage 4 or 5 CKD (non-dialysis dependent); 22 clinicians (6 CKD community nurses, 1 clinical psychologist, 10 nephrologists, 3 specialist registrars, and 2 renal surgeons) in the United Kingdom. ANALYTICAL APPROACH: Semi-structured interviews and focus group discussion during which patients received paper versions of the Kidney Disease Quality of Life-36 and the Integrated Patient Outcome Scale-Renal to exemplify the type of content that could be included in an ePROM. Thematic analysis of interview transcripts. RESULTS: 4 themes were identified: (1) general opinions of PROMs, (2) potential benefits and applications of an ePROM system, (3) practical considerations for the implementation of ePROMs, and (4) concerns, barriers, and facilitators. Patients were willing to complete ePROMs on a regular basis as part of their care despite clinician concerns about patient burden. Patients assessed the questionnaires favorably. Clinicians suggested that the extent of adoption of renal ePROM systems in routine clinical settings should be based on evidence of significant impact on patient outcomes. Clinicians were concerned that an ePROM system may raise patient expectations to unrealistic levels and expose clinicians to the risk for litigation. Patients and clinicians identified potential benefits and highlighted issues and concerns that need to be addressed to ensure the successful implementation of the renal ePROM system. LIMITATIONS: Transferability of the findings may be limited because only English-speaking participants were recruited to the study. CONCLUSIONS: A renal ePROM system may play a supportive role in the routine clinical management of patients with advanced CKD if the concerns of clinicians and patients can be sufficiently addressed.
Assuntos
Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Insuficiência Renal Crônica/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Índice de Gravidade de DoençaRESUMO
BACKGROUND: All studies classified as research involving human participants require research ethics review. Most regulation and guidance on ethical oversight of research involving human participants was written for pharmacotherapy interventions. Interpretation of such guidance for cluster-randomized trials and stepped-wedge trials, which commonly evaluate complex non-therapeutic interventions such as knowledge translation, public health, or health service delivery interventions, can pose challenges to researchers and regulators. CURRENT GUIDANCE: The Ottawa Statement on the Ethical Design and Conduct of Cluster-Randomized Trials provides guidance on the ethical oversight and consent procedures for cluster-randomized trials, and while not explicit, this includes stepped-wedge trials. Yet, stepped-wedge trials have unique characteristics that differentiate them from standard cluster-randomized trials. In particular, they can be used to evaluate knowledge translation interventions within the context of a routine health system rollout; they may have a non-randomized design; and the decision to implement the intervention is not always made by the researcher. Many stepped-wedge trials do not undergo ethical review and do not report trial registration. This suggests that those undertaking these studies and research ethics committees perceive them as non-research activities. RECOMMENDATIONS: Through an ethical analysis of two case studies, we argue that stepped-wedge trials, like parallel arm cluster trials, are systematic investigations designed to produce generalizable knowledge. We contend that stepped-wedge trials usually include human research participants, which may be patients, health care providers, or both. Stepped-wedge trials are therefore research involving human participants for the purpose of ethical review. Nevertheless, the use of a waiver or alteration of consent may be appropriate in many stepped-wedge trials due to the infeasibility of obtaining informed consent and the low-risk nature of the interventions. To ensure that traditional ethical principles such as respect for persons are upheld, these studies must undergo research ethics review.
Assuntos
Ensaios Clínicos como Assunto/ética , Ensaios Clínicos como Assunto/métodos , Atenção à Saúde , Revisão Ética , Pesquisa Biomédica/ética , Comitês de Ética em Pesquisa , Ética em Pesquisa , Humanos , Consentimento Livre e Esclarecido , Melhoria de Qualidade , Ensaios Clínicos Controlados Aleatórios como Assunto/ética , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , PesquisadoresRESUMO
Selective attention is reflected neurally in changes in the power of posterior neural oscillations in the alpha (8-12 Hz) and gamma (40-100 Hz) bands. Although a neural mechanism that allows relevant information to be selectively processed has its advantages, it may lead to lucrative or dangerous information going unnoticed. Neural systems are also in place for processing rewarding and punishing information. Here, we examine the interaction between selective attention (left vs. right) and stimulus's learned value associations (neutral, punished, or rewarded) and how they compete for control of posterior neural oscillations. We found that both attention and stimulus-value associations influenced neural oscillations. Whereas selective attention had comparable effects on alpha and gamma oscillations, value associations had dissociable effects on these neural markers of attention. Salient targets (associated with positive and negative outcomes) hijacked changes in alpha power-increasing hemispheric alpha lateralization when salient targets were attended, decreasing it when they were being ignored. In contrast, hemispheric gamma-band lateralization was specifically abolished by negative distractors. Source analysis indicated occipital generators of both attentional and value effects. Thus, posterior cortical oscillations support both the ability to selectively attend while at the same time retaining the ability to remain sensitive to valuable features in the environment. Moreover, the versatility of our attentional system to respond separately to salient from merely positively valued stimuli appears to be carried out by separate neural processes reflected in different frequency bands.
Assuntos
Ritmo alfa/fisiologia , Associação , Atenção/fisiologia , Ritmo Gama/fisiologia , Lobo Occipital/fisiologia , Feminino , Lateralidade Funcional , Humanos , Magnetoencefalografia , Masculino , Testes Neuropsicológicos , Adulto JovemRESUMO
BACKGROUND AND PURPOSE: Primary prevention of stroke and transient ischemic attack (TIA) is important to reduce the burden of these conditions; however, prescribing of prevention drugs is suboptimal. We aimed to identify individual clinical and demographic characteristics associated with potential missed opportunities for prevention therapy with lipid-lowering, anticoagulant, or antihypertensive drugs before stroke/TIA. METHODS: We analyzed anonymized electronic primary care records from a UK primary care database that covers 561 family practices. Patients with first-ever stroke/TIA, ≥18 years, with diagnosis between January 1, 2009, and December 31, 2013, were included. Missed opportunities for prevention were defined as people with clinical indications for lipid-lowering, anticoagulant, or antihypertensive drugs but not prescribed these drugs before their stroke/TIA. Mixed-effect logistic regression models evaluated the relationship between missed opportunities and individual clinical/demographic characteristics. RESULTS: The inclusion criteria were met by 29 043 people with stroke/TIA. Patients with coronary heart disease, chronic kidney disease, peripheral arterial disease, or diabetes mellitus were at less risk of a missed opportunity for prescription of lipid-lowering and antihypertensive drugs. However, patients with a 10-year cardiovascular disease risk ≥20% but without these diagnoses had increased risk of having a missed opportunity for prescription of lipid-lowering drugs or antihypertensive drugs. Women were less likely to be prescribed anticoagulants but more likely to be prescribed antihypertensive drugs. The elderly (≥85 years of age) were less likely to be prescribed all 3 prevention drugs, compared with people aged 75 to 79 years. CONCLUSIONS: Knowing the patient characteristics predictive of missed opportunities for stroke prevention may help primary care identify and appropriately manage these patients. Improving the management of these groups may reduce their risk and potentially prevent large number of future strokes and TIAs in the population.