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1.
Epidemiology ; 35(4): 568-578, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38912714

RESUMEN

BACKGROUND: The UK delivered its first "booster" COVID-19 vaccine doses in September 2021, initially to individuals at high risk of severe disease, then to all adults. The BNT162b2 Pfizer-BioNTech vaccine was used initially, then also Moderna mRNA-1273. METHODS: With the approval of the National Health Service England, we used routine clinical data to estimate the effectiveness of boosting with BNT162b2 or mRNA-1273 compared with no boosting in eligible adults who had received two primary course vaccine doses. We matched each booster recipient with an unboosted control on factors relating to booster priority status and prior COVID-19 immunization. We adjusted for additional factors in Cox models, estimating hazard ratios up to 182 days (6 months) following booster dose. We estimated hazard ratios overall and within the following periods: 1-14, 15-42, 43-69, 70-97, 98-126, 127-152, and 155-182 days. Outcomes included a positive SARS-CoV-2 test, COVID-19 hospitalization, COVID-19 death, non-COVID-19 death, and fracture. RESULTS: We matched 8,198,643 booster recipients with unboosted controls. Adjusted hazard ratios over 6-month follow-up were: positive SARS-CoV-2 test 0.75 (0.74, 0.75); COVID-19 hospitalization 0.30 (0.29, 0.31); COVID-19 death 0.11 (0.10, 0.14); non-COVID-19 death 0.22 (0.21, 0.23); and fracture 0.77 (0.75, 0.78). Estimated effectiveness of booster vaccines against severe COVID-19-related outcomes peaked during the first 3 months following the booster dose. By 6 months, the cumulative incidence of positive SARS-CoV-2 test was higher in boosted than unboosted individuals. CONCLUSIONS: We estimate that COVID-19 booster vaccination, compared with no booster vaccination, provided substantial protection against COVID-19 hospitalization and COVID-19 death but only limited protection against positive SARS-CoV-2 test. Lower rates of fracture in boosted than unboosted individuals may suggest unmeasured confounding. Observational studies should report estimated vaccine effectiveness against nontarget and negative control outcomes.


Asunto(s)
Vacuna nCoV-2019 mRNA-1273 , Vacuna BNT162 , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , SARS-CoV-2 , Humanos , Inglaterra/epidemiología , COVID-19/prevención & control , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , SARS-CoV-2/inmunología , Vacunas contra la COVID-19/administración & dosificación , Eficacia de las Vacunas , Modelos de Riesgos Proporcionales , Hospitalización/estadística & datos numéricos
2.
BJOG ; 131(2): 222-230, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37431533

RESUMEN

OBJECTIVE: Investigate cost-effectiveness of first trimester pre-eclampsia screening using the Fetal Medicine Foundation (FMF) algorithm and targeted aspirin prophylaxis in comparison with standard care. DESIGN: Retrospective observational study. SETTING: London tertiary hospital. POPULATION: 5957 pregnancies screened for pre-eclampsia using the National Institute for Health and Care Excellence (NICE) method. METHODS: Differences in pregnancy outcomes between those who developed pre-eclampsia, term pre-eclampsia and preterm pre-eclampsia were compared by the Kruskal-Wallis and Chi-square tests. The FMF algorithm was applied retrospectively to the cohort. A decision analytic model was used to estimate costs and outcomes for pregnancies screened using NICE and those screened using the FMF algorithm. The decision point probabilities were calculated using the included cohort. MAIN OUTCOME MEASURES: Incremental healthcare costs and QALY gained per pregnancy screened. RESULTS: Of 5957 pregnancies, 12.8% and 15.9% were screen-positive for development of pre-eclampsia using the NICE and FMF methods, respectively. Of those who were screen-positive by NICE recommendations, aspirin was not prescribed in 25%. Across the three groups, namely, pregnancies without pre-eclampsia, term pre-eclampsia and preterm pre-eclampsia there was a statistically significant trend in rates of emergency caesarean (respectively 21%, 43% and 71.4%; P < 0.001), admission to neonatal intensive care unit (NICU) (5.9%, 9.4%, 41%; P < 0.001) and length of stay in NICU. The FMF algorithm was associated with seven fewer cases of preterm pre-eclampsia, cost saving of £9.06 and QALY gain of 0.00006/pregnancy screened. CONCLUSIONS: Using a conservative approach, application of the FMF algorithm achieved clinical benefit and an economic cost saving.


Asunto(s)
Aspirina , Preeclampsia , Embarazo , Femenino , Recién Nacido , Humanos , Aspirina/uso terapéutico , Primer Trimestre del Embarazo , Preeclampsia/diagnóstico , Preeclampsia/prevención & control , Preeclampsia/tratamiento farmacológico , Estudios de Cohortes , Estudios Retrospectivos , Análisis Costo-Beneficio
3.
Ann Intern Med ; 176(5): 685-693, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37126810

RESUMEN

The COVID-19 vaccines were developed and rigorously evaluated in randomized trials during 2020. However, important questions, such as the magnitude and duration of protection, their effectiveness against new virus variants, and the effectiveness of booster vaccination, could not be answered by randomized trials and have therefore been addressed in observational studies. Analyses of observational data can be biased because of confounding and because of inadequate design that does not consider the evolution of the pandemic over time and the rapid uptake of vaccination. Emulating a hypothetical "target trial" using observational data assembled during vaccine rollouts can help manage such potential sources of bias. This article describes 2 approaches to target trial emulation. In the sequential approach, on each day, eligible persons who have not yet been vaccinated are matched to a vaccinated person. The single-trial approach sets a single baseline at the start of the rollout and considers vaccination as a time-varying variable. The nature of the confounding depends on the analysis strategy: Estimating "per-protocol" effects (accounting for vaccination of initially unvaccinated persons after baseline) may require adjustment for both baseline and "time-varying" confounders. These issues are illustrated by using observational data from 2 780 931 persons in the United Kingdom aged 70 years or older to estimate the effect of a first dose of a COVID-19 vaccine. Addressing the issues discussed in this article should help authors of observational studies provide robust evidence to guide clinical and policy decisions.


Asunto(s)
COVID-19 , Vacunas , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Inmunización Secundaria , Vacunación
4.
PLoS Med ; 20(1): e1004174, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36716318

RESUMEN

BACKGROUND: Sepsis is characterised by dysregulated, life-threatening immune responses, which are thought to be driven by cytokines such as interleukin 6 (IL-6). Genetic variants in IL6R known to down-regulate IL-6 signalling are associated with improved Coronavirus Disease 2019 (COVID-19) outcomes, a finding later confirmed in randomised trials of IL-6 receptor antagonists (IL6RAs). We hypothesised that blockade of IL6R could also improve outcomes in sepsis. METHODS AND FINDINGS: We performed a Mendelian randomisation (MR) analysis using single nucleotide polymorphisms (SNPs) in and near IL6R to evaluate the likely causal effects of IL6R blockade on sepsis (primary outcome), sepsis severity, other infections, and COVID-19 (secondary outcomes). We weighted SNPs by their effect on CRP and combined results across them in inverse variance weighted meta-analysis, proxying the effect of IL6RA. Our outcomes were measured in UK Biobank, FinnGen, the COVID-19 Host Genetics Initiative (HGI), and the GenOSept and GainS consortium. We performed several sensitivity analyses to test assumptions of our methods, including utilising variants around CRP and gp130 in a similar analysis. In the UK Biobank cohort (N = 486,484, including 11,643 with sepsis), IL6R blockade was associated with a decreased risk of our primary outcome, sepsis (odds ratio (OR) = 0.80; 95% confidence interval (CI) 0.66 to 0.96, per unit of natural log-transformed CRP decrease). The size of this effect increased with severity, with larger effects on 28-day sepsis mortality (OR = 0.74; 95% CI 0.47 to 1.15); critical care admission with sepsis (OR = 0.48, 95% CI 0.30 to 0.78) and critical care death with sepsis (OR = 0.37, 95% CI 0.14 to 0.98). Similar associations were seen with severe respiratory infection: OR for pneumonia in critical care 0.69 (95% CI 0.49 to 0.97) and for sepsis survival in critical care (OR = 0.22; 95% CI 0.04 to 1.31) in the GainS and GenOSept consortium, although this result had a large degree of imprecision. We also confirm the previously reported protective effect of IL6R blockade on severe COVID-19 (OR = 0.69, 95% CI 0.57 to 0.84) in the COVID-19 HGI, which was of similar magnitude to that seen in sepsis. Sensitivity analyses did not alter our primary results. These results are subject to the limitations and assumptions of MR, which in this case reflects interpretation of these SNP effects as causally acting through blockade of IL6R, and reflect lifetime exposure to IL6R blockade, rather than the effect of therapeutic IL6R blockade. CONCLUSIONS: IL6R blockade is causally associated with reduced incidence of sepsis. Similar but imprecisely estimated results supported a causal effect also on sepsis related mortality and critical care admission with sepsis. These effects are comparable in size to the effect seen in severe COVID-19, where IL-6 receptor antagonists were shown to improve survival. These data suggest that a randomised trial of IL-6 receptor antagonists in sepsis should be considered.


Asunto(s)
COVID-19 , Sepsis , Humanos , Interleucina-6/genética , Hospitalización , Receptores de Interleucina-6/genética , Sepsis/tratamiento farmacológico , Sepsis/genética , Análisis de la Aleatorización Mendeliana
5.
Biom J ; 65(8): e2200116, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37727079

RESUMEN

Randomized controlled trials (RCTs) are vulnerable to bias from missing data. When outcomes are missing not at random (MNAR), estimates from complete case analysis (CCA) and multiple imputation (MI) may be biased. There is no statistical test for distinguishing between outcomes missing at random (MAR) and MNAR. Current strategies rely on comparing dropout proportions and covariate distributions, and using auxiliary information to assess the likelihood of dropout being associated with the outcome. We propose using the observed variance difference across trial arms as a tool for assessing the risk of dropout being MNAR in RCTs with continuous outcomes. In an RCT, at randomization, the distributions of all covariates should be equal in the populations randomized to the intervention and control arms. Under the assumption of homogeneous treatment effects and homoskedastic outcome errors, the variance of the outcome will also be equal in the two populations over the course of follow-up. We show that under MAR dropout, the observed outcome variances, conditional on the variables included in the model, are equal across trial arms, whereas MNAR dropout may result in unequal variances. Consequently, unequal observed conditional trial arm variances are an indicator of MNAR dropout and possible bias of the estimated treatment effect. Heterogeneous treatment effects or heteroskedastic outcome errors are another potential cause of observing different outcome variances. We show that for longitudinal data, we can isolate the effect of MNAR outcome-dependent dropout by considering the variance difference at baseline in the same set of patients who are observed at final follow-up. We illustrate our method in simulation for CCA and MI, and in applications using individual-level data and summary data.


Asunto(s)
Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Simulación por Computador , Probabilidad , Sesgo
6.
J Infect Dis ; 226(11): 1877-1881, 2022 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-35429382

RESUMEN

General population studies have shown strong humoral response following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination with subsequent waning of anti-spike antibody levels. Vaccine-induced immune responses are often attenuated in frail and older populations, but published data are scarce. We measured SARS-CoV-2 anti-spike antibody levels in long-term care facility residents and staff following a second vaccination dose with Oxford-AstraZeneca or Pfizer-BioNTech. Vaccination elicited robust antibody responses in older residents, suggesting comparable levels of vaccine-induced immunity to that in the general population. Antibody levels are higher after Pfizer-BioNTech vaccination but fall more rapidly compared to Oxford-AstraZeneca recipients and are enhanced by prior infection in both groups.


Asunto(s)
COVID-19 , Vacunas , Humanos , Anciano , SARS-CoV-2 , ChAdOx1 nCoV-19 , Vacuna BNT162 , Cuidados a Largo Plazo , COVID-19/prevención & control , Anticuerpos Antivirales , Inglaterra
7.
J Nutr ; 152(10): 2255-2268, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-35687367

RESUMEN

BACKGROUND: Economic evaluations of nutrition-sensitive agriculture (NSA) interventions are scarce, limiting assessment of their potential affordability and scalability. OBJECTIVES: We conducted cost-consequence analyses of 3 participatory video-based interventions of fortnightly women's group meetings using the following platforms: 1) NSA videos; 2) NSA and nutrition-specific videos; or 3) NSA videos with a nutrition-specific participatory learning and action (PLA) cycle. METHODS: Interventions were tested in a 32-mo, 4-arm cluster-randomized controlled trial, Upscaling Participatory Action and Videos for Agriculture and Nutrition (UPAVAN) in the Keonjhar district, Odisha, India. Impacts were evaluated in children aged 0-23 mo and their mothers. We estimated program costs using data collected prospectively from expenditure records of implementing and technical partners and societal costs using expenditure assessment data collected from households with a child aged 0-23 mo and key informant interviews. Costs were adjusted for inflation, discounted, and converted to 2019 US$. RESULTS: Total program costs of each intervention ranged from US$272,121 to US$386,907. Program costs per pregnant woman or mother of a child aged 0-23 mo were US$62 for NSA videos, US$84 for NSA and nutrition-specific videos, and US$78 for NSA videos with PLA (societal costs: US$125, US$143, and US$122, respectively). Substantial shares of total costs were attributable to development and delivery of the videos and PLA (52-69%) and quality assurance (25-41%). Relative to control, minimum dietary diversity was higher in the children who underwent the interventions incorporating nutrition-specific videos and PLA (adjusted RRs: 1.19 and 1.27; 95% CIs: 1.03-1.37 and 1.11, 1.46, respectively). Relative to control, minimum dietary diversity in mothers was higher in those who underwent NSA video (1.21 [1.01, 1.45]) and NSA with PLA (1.30 [1.10, 1.53]) interventions. CONCLUSION: NSA videos with PLA can increase both maternal and child dietary diversity and have the lowest cost per unit increase in diet diversity. Building on investments made in developing UPAVAN, cost-efficiency at scale could be increased with less intensive monitoring, reduced startup costs, and integration within existing government programs. This trial was registered at clinicaltrials.gov as ISRCTN65922679.


Asunto(s)
Dieta , Estado Nutricional , Agricultura , Niño , Análisis Costo-Beneficio , Femenino , Humanos , India , Poliésteres , Embarazo
8.
PLoS Comput Biol ; 17(9): e1009255, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34570767

RESUMEN

Approximately 85% of tuberculosis (TB) related deaths occur in low- and middle-income countries where health resources are scarce. Effective priority setting is required to maximise the impact of limited budgets. The Optima TB tool has been developed to support analytical capacity and inform evidence-based priority setting processes for TB health benefits package design. This paper outlines the Optima TB framework and how it was applied in Belarus, an upper-middle income country in Eastern Europe with a relatively high burden of TB. Optima TB is a population-based disease transmission model, with programmatic cost functions and an optimisation algorithm. Modelled populations include age-differentiated general populations and higher-risk populations such as people living with HIV. Populations and prospective interventions are defined in consultation with local stakeholders. In partnership with the latter, demographic, epidemiological, programmatic, as well as cost and spending data for these populations and interventions are then collated. An optimisation analysis of TB spending was conducted in Belarus, using program objectives and constraints defined in collaboration with local stakeholders, which included experts, decision makers, funders and organisations involved in service delivery, support and technical assistance. These analyses show that it is possible to improve health impact by redistributing current TB spending in Belarus. Specifically, shifting funding from inpatient- to outpatient-focused care models, and from mass screening to active case finding strategies, could reduce TB prevalence and mortality by up to 45% and 50%, respectively, by 2035. In addition, an optimised allocation of TB spending could lead to a reduction in drug-resistant TB infections by 40% over this period. This would support progress towards national TB targets without additional financial resources. The case study in Belarus demonstrates how reallocations of spending across existing and new interventions could have a substantial impact on TB outcomes. This highlights the potential for Optima TB and similar modelling tools to support evidence-based priority setting.


Asunto(s)
Asignación de Recursos/economía , Programas Informáticos , Tuberculosis/economía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Niño , Preescolar , Biología Computacional , Análisis Costo-Beneficio , Femenino , Costos de la Atención en Salud/estadística & datos numéricos , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Modelos Biológicos , Modelos Económicos , Prevalencia , Estudios Prospectivos , República de Belarús/epidemiología , Tuberculosis/epidemiología , Tuberculosis/transmisión , Adulto Joven
9.
Stat Med ; 41(8): 1462-1481, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35098576

RESUMEN

Outcome values in randomized controlled trials (RCTs) may be missing not at random (MNAR), if patients with extreme outcome values are more likely to drop out (eg, due to perceived ineffectiveness of treatment, or adverse effects). In such scenarios, estimates from complete case analysis (CCA) and multiple imputation (MI) will be biased. We investigate the use of the trimmed means (TM) estimator for the case of univariable missingness in one continuous outcome. The TM estimator operates by setting missing values to the most extreme value, and then "trimming" away equal fractions of both groups, estimating the treatment effect using the remaining data. The TM estimator relies on two assumptions, which we term the "strong MNAR" and "location shift" assumptions. We derive formulae for the TM estimator bias resulting from the violation of these assumptions for normally distributed outcomes. We propose an adjusted TM estimator, which relaxes the location shift assumption and detail how our bias formulae can be used to establish the direction of bias of CCA and TM estimates, to inform sensitivity analyses. The TM approach is illustrated in a sensitivity analysis of the CoBalT RCT of cognitive behavioral therapy (CBT) in 469 individuals with 46 months follow-up. Results were consistent with a beneficial CBT treatment effect, with MI estimates closer to the null and TM estimates further from the null than the CCA estimate. We propose using the TM estimator as a sensitivity analysis for data where extreme outcome value dropout is plausible.


Asunto(s)
Ensayos Clínicos como Asunto , Pacientes Desistentes del Tratamiento , Sesgo , Humanos
10.
Pediatr Diabetes ; 23(1): 19-32, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34713540

RESUMEN

BACKGROUND: The changing diabetes in children (CDiC) project is a public-private partnership implemented by Novo Nordisk, to improve access to diabetes care for children with type 1 diabetes. This paper outlines the findings from an evaluation of CDiC in Bangladesh and Kenya, assessing whether CDiC has achieved its objectives in each of six core program components. RESEARCH DESIGN AND METHODS: The Rapid Assessment Protocol for Insulin Access (RAPIA) framework was used to analyze the path of insulin provision and the healthcare infrastructure in place for diagnosis and treatment of diabetes. The RAPIA facilitates a mixed-methods approach to multiple levels of data collection and systems analysis. Information is collected through questionnaires, in-depth interviews and focus group discussions, site visits, and document reviews, engaging a wide range of stakeholders (N = 127). All transcripts were analyzed thematically. RESULTS: The CDiC scheme provides a stable supply of free insulin to children in implementing facilities in Kenya and Bangladesh, and offers a comprehensive package of pediatric diabetes care. However, some elements of the CDiC program were not functioning as originally intended. Transitions away from donor funding and toward government ownership are a particular concern, as patients may incur additional treatment costs, while services offered may be reduced. Additionally, despite subsidized treatment costs, indirect costs remain a substantial barrier to care. CONCLUSION: Public-private partnerships such as the CDiC program can improve access to life-saving medicines. However, our analysis found several limitations, including concerns over the sustainability of the project in both countries. Any program reliant on external funding and delivered in a high-turnover staffing environment will be vulnerable to sustainability concerns.


Asunto(s)
Diabetes Mellitus/terapia , Accesibilidad a los Servicios de Salud/normas , Adolescente , Bangladesh/epidemiología , Niño , Preescolar , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Femenino , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Lactante , Kenia/epidemiología , Masculino , Asociación entre el Sector Público-Privado/tendencias , Adulto Joven
11.
Qual Health Res ; 32(1): 145-158, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34841984

RESUMEN

Focusing only on biomedical targets neglects the important role that psychosocial factors play in effective diabetes self-management. This study aims to understand the lived experiences of children with Type 1 Diabetes (T1DM) in Kenya. Children (n = 15) participated in focus group discussions and photo diary data collection. Focus group discussions and semi-structured interviews were also conducted with caregivers (n = 14). We describe an adaptation to diabetes over time, identifying four overarching themes: knowledge and awareness, economic exclusion, the importance of social support, and striving for normality. Photo diaries are then categorized to explore daily realities of diabetes management. Children with T1DM in Kenya face varied barriers to care but can lead a "normal" and fulfilling life, provided adequate support is in place. To improve the lives of children with diabetes in this context and others like it, stakeholders must take note of children's experiences and recognize their multidimensional needs.


Asunto(s)
Diabetes Mellitus Tipo 1 , Cuidadores , Niño , Diabetes Mellitus Tipo 1/terapia , Grupos Focales , Humanos , Kenia , Investigación Cualitativa
12.
Epidemiology ; 32(2): 194-201, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33470711

RESUMEN

Advice regarding the analysis of observational studies of exposure effects usually is against adjustment for factors that occur after the exposure, as they may be caused by the exposure (or mediate the effect of exposure on outcome), so potentially leading to collider stratification bias. However, such factors could also be caused by unmeasured confounding factors, in which case adjusting for them will also remove some of the bias due to confounding. We derive expressions for collider stratification bias when conditioning and confounding bias when not conditioning on the mediator, in the presence of unmeasured confounding (assuming that all associations are linear and there are no interactions). Using simulations, we show that generally neither the conditioned nor the unconditioned estimate is unbiased, and the trade-off between them depends on the magnitude of the effect of the exposure that is mediated relative to the effect of the unmeasured confounders and their relations with the mediator. We illustrate the use of the bias expressions via three examples: neuroticism and mortality (adjusting for the mediator appears the least biased option), glycated hemoglobin levels and systolic blood pressure (adjusting gives smaller bias), and literacy in primary school pupils (not adjusting gives smaller bias). Our formulae and simulations can inform quantitative bias analysis as well as analysis strategies for observational studies in which there is a potential for unmeasured confounding.


Asunto(s)
Factores de Confusión Epidemiológicos , Sesgo , Humanos
13.
Euro Surveill ; 26(46)2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34794537

RESUMEN

We describe the impact of changing epidemiology and vaccine introduction on characteristics of COVID-19 outbreaks in 330 long-term care facilities (LTCF) in England between November 2020 and June 2021. As vaccine coverage in LTCF increased and national incidence declined, the total number of outbreaks and outbreak severity decreased across the LTCF. The number of infected cases per outbreak decreased by 80.6%, while the proportion of outbreaks affecting staff only increased. Our study supports findings of vaccine effectiveness in LTCF.


Asunto(s)
COVID-19 , Vacunas , Brotes de Enfermedades/prevención & control , Humanos , Cuidados a Largo Plazo , SARS-CoV-2
14.
PLoS Med ; 17(3): e1003062, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32203549

RESUMEN

BACKGROUND: Circulating lipoprotein lipids cause coronary heart disease (CHD). However, the precise way in which one or more lipoprotein lipid-related entities account for this relationship remains unclear. Using genetic instruments for lipoprotein lipid traits implemented through multivariable Mendelian randomisation (MR), we sought to compare their causal roles in the aetiology of CHD. METHODS AND FINDINGS: We conducted a genome-wide association study (GWAS) of circulating non-fasted lipoprotein lipid traits in the UK Biobank (UKBB) for low-density lipoprotein (LDL) cholesterol, triglycerides, and apolipoprotein B to identify lipid-associated single nucleotide polymorphisms (SNPs). Using data from CARDIoGRAMplusC4D for CHD (consisting of 60,801 cases and 123,504 controls), we performed univariable and multivariable MR analyses. Similar GWAS and MR analyses were conducted for high-density lipoprotein (HDL) cholesterol and apolipoprotein A-I. The GWAS of lipids and apolipoproteins in the UKBB included between 393,193 and 441,016 individuals in whom the mean age was 56.9 y (range 39-73 y) and of whom 54.2% were women. The mean (standard deviation) lipid concentrations were LDL cholesterol 3.57 (0.87) mmol/L and HDL cholesterol 1.45 (0.38) mmol/L, and the median triglycerides was 1.50 (IQR = 1.11) mmol/L. The mean (standard deviation) values for apolipoproteins B and A-I were 1.03 (0.24) g/L and 1.54 (0.27) g/L, respectively. The GWAS identified multiple independent SNPs associated at P < 5 × 10-8 for LDL cholesterol (220), apolipoprotein B (n = 255), triglycerides (440), HDL cholesterol (534), and apolipoprotein A-I (440). Between 56%-93% of SNPs identified for each lipid trait had not been previously reported in large-scale GWASs. Almost half (46%) of these SNPs were associated at P < 5 × 10-8 with more than one lipid-related trait. Assessed individually using MR, LDL cholesterol (odds ratio [OR] 1.66 per 1-standard-deviation-higher trait; 95% CI: 1.49-1.86; P < 0.001), triglycerides (OR 1.34; 95% CI: 1.25-1.44; P < 0.001) and apolipoprotein B (OR 1.73; 95% CI: 1.56-1.91; P < 0.001) had effect estimates consistent with a higher risk of CHD. In multivariable MR, only apolipoprotein B (OR 1.92; 95% CI: 1.31-2.81; P < 0.001) retained a robust effect, with the estimate for LDL cholesterol (OR 0.85; 95% CI: 0.57-1.27; P = 0.44) reversing and that of triglycerides (OR 1.12; 95% CI: 1.02-1.23; P = 0.01) becoming weaker. Individual MR analyses showed a 1-standard-deviation-higher HDL cholesterol (OR 0.80; 95% CI: 0.75-0.86; P < 0.001) and apolipoprotein A-I (OR 0.83; 95% CI: 0.77-0.89; P < 0.001) to lower the risk of CHD, but these effect estimates attenuated substantially to the null on accounting for apolipoprotein B. A limitation is that, owing to the nature of lipoprotein metabolism, measures related to the composition of lipoprotein particles are highly correlated, creating a challenge in making exclusive interpretations on causation of individual components. CONCLUSIONS: These findings suggest that apolipoprotein B is the predominant trait that accounts for the aetiological relationship of lipoprotein lipids with risk of CHD.


Asunto(s)
Apolipoproteína B-100/genética , Enfermedad Coronaria/genética , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Apolipoproteína A-I/sangre , Apolipoproteína A-I/genética , Apolipoproteína B-100/sangre , Biomarcadores/sangre , HDL-Colesterol/sangre , HDL-Colesterol/genética , LDL-Colesterol/sangre , LDL-Colesterol/genética , Enfermedad Coronaria/sangre , Enfermedad Coronaria/diagnóstico , Femenino , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Análisis de la Aleatorización Mendeliana , Persona de Mediana Edad , Análisis Multivariante , Fenotipo , Medición de Riesgo , Factores de Riesgo , Triglicéridos/sangre
15.
PLoS Med ; 16(1): e1002739, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30703100

RESUMEN

BACKGROUND: Psoriasis is a common inflammatory skin disease that has been reported to be associated with obesity. We aimed to investigate a possible causal relationship between body mass index (BMI) and psoriasis. METHODS AND FINDINGS: Following a review of published epidemiological evidence of the association between obesity and psoriasis, mendelian randomization (MR) was used to test for a causal relationship with BMI. We used a genetic instrument comprising 97 single-nucleotide polymorphisms (SNPs) associated with BMI as a proxy for BMI (expected to be much less confounded than measured BMI). One-sample MR was conducted using individual-level data (396,495 individuals) from the UK Biobank and the Nord-Trøndelag Health Study (HUNT), Norway. Two-sample MR was performed with summary-level data (356,926 individuals) from published BMI and psoriasis genome-wide association studies (GWASs). The one-sample and two-sample MR estimates were meta-analysed using a fixed-effect model. To test for a potential reverse causal effect, MR analysis with genetic instruments comprising variants from recent genome-wide analyses for psoriasis were used to test whether genetic risk for this skin disease has a causal effect on BMI. Published observational data showed an association of higher BMI with psoriasis. A mean difference in BMI of 1.26 kg/m2 (95% CI 1.02-1.51) between psoriasis cases and controls was observed in adults, while a 1.55 kg/m2 mean difference (95% CI 1.13-1.98) was observed in children. The observational association was confirmed in UK Biobank and HUNT data sets. Overall, a 1 kg/m2 increase in BMI was associated with 4% higher odds of psoriasis (meta-analysis odds ratio [OR] = 1.04; 95% CI 1.03-1.04; P = 1.73 × 10(-60)). MR analyses provided evidence that higher BMI causally increases the odds of psoriasis (by 9% per 1 unit increase in BMI; OR = 1.09 (1.06-1.12) per 1 kg/m2; P = 4.67 × 10(-9)). In contrast, MR estimates gave little support to a possible causal effect of psoriasis genetic risk on BMI (0.004 kg/m2 change in BMI per doubling odds of psoriasis (-0.003 to 0.011). Limitations of our study include possible misreporting of psoriasis by patients, as well as potential misdiagnosis by clinicians. In addition, there is also limited ethnic variation in the cohorts studied. CONCLUSIONS: Our study, using genetic variants as instrumental variables for BMI, provides evidence that higher BMI leads to a higher risk of psoriasis. This supports the prioritization of therapies and lifestyle interventions aimed at controlling weight for the prevention or treatment of this common skin disease. Mechanistic studies are required to improve understanding of this relationship.


Asunto(s)
Índice de Masa Corporal , Psoriasis/etiología , Adolescente , Adulto , Anciano , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Análisis de la Aleatorización Mendeliana , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/genética , Polimorfismo de Nucleótido Simple/genética , Psoriasis/genética , Factores de Riesgo , Adulto Joven
17.
Circulation ; 135(24): 2373-2388, 2017 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-28500271

RESUMEN

BACKGROUND: The implications of different adiposity measures on cardiovascular disease etiology remain unclear. In this article, we quantify and contrast causal associations of central adiposity (waist-to-hip ratio adjusted for body mass index [WHRadjBMI]) and general adiposity (body mass index [BMI]) with cardiometabolic disease. METHODS: Ninety-seven independent single-nucleotide polymorphisms for BMI and 49 single-nucleotide polymorphisms for WHRadjBMI were used to conduct Mendelian randomization analyses in 14 prospective studies supplemented with coronary heart disease (CHD) data from CARDIoGRAMplusC4D (Coronary Artery Disease Genome-wide Replication and Meta-analysis [CARDIoGRAM] plus The Coronary Artery Disease [C4D] Genetics; combined total 66 842 cases), stroke from METASTROKE (12 389 ischemic stroke cases), type 2 diabetes mellitus from DIAGRAM (Diabetes Genetics Replication and Meta-analysis; 34 840 cases), and lipids from GLGC (Global Lipids Genetic Consortium; 213 500 participants) consortia. Primary outcomes were CHD, type 2 diabetes mellitus, and major stroke subtypes; secondary analyses included 18 cardiometabolic traits. RESULTS: Each one standard deviation (SD) higher WHRadjBMI (1 SD≈0.08 U) associated with a 48% excess risk of CHD (odds ratio [OR] for CHD, 1.48; 95% confidence interval [CI], 1.28-1.71), similar to findings for BMI (1 SD≈4.6 kg/m2; OR for CHD, 1.36; 95% CI, 1.22-1.52). Only WHRadjBMI increased risk of ischemic stroke (OR, 1.32; 95% CI, 1.03-1.70). For type 2 diabetes mellitus, both measures had large effects: OR, 1.82 (95% CI, 1.38-2.42) and OR, 1.98 (95% CI, 1.41-2.78) per 1 SD higher WHRadjBMI and BMI, respectively. Both WHRadjBMI and BMI were associated with higher left ventricular hypertrophy, glycemic traits, interleukin 6, and circulating lipids. WHRadjBMI was also associated with higher carotid intima-media thickness (39%; 95% CI, 9%-77% per 1 SD). CONCLUSIONS: Both general and central adiposity have causal effects on CHD and type 2 diabetes mellitus. Central adiposity may have a stronger effect on stroke risk. Future estimates of the burden of adiposity on health should include measures of central and general adiposity.


Asunto(s)
Adiposidad/genética , Distribución de la Grasa Corporal/métodos , Enfermedad Coronaria/genética , Diabetes Mellitus Tipo 2/genética , Análisis de la Aleatorización Mendeliana/métodos , Accidente Cerebrovascular/genética , Enfermedad Coronaria/epidemiología , Diabetes Mellitus Tipo 2/epidemiología , Humanos , Estudios Longitudinales , Estudios Observacionales como Asunto/métodos , Polimorfismo de Nucleótido Simple/genética , Estudios Prospectivos , Accidente Cerebrovascular/epidemiología
18.
Dev Med Child Neurol ; 60(3): 275-282, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29238964

RESUMEN

AIM: Difficulties in reading comprehension can arise from either word reading or listening comprehension difficulties, or a combination of the two. We sought to determine whether children with rolandic epilepsy had poor reading comprehension relative to typically developing comparison children, and whether such difficulties were associated with word reading and/or general language comprehension difficulties. METHOD: In this cross-sectional study, children with rolandic epilepsy (n=25; 16 males, 9 females; mean age 9y 1mo, SD 1y 7mo) and a comparison group (n=39; 25 males, 14 females; mean age 9y 1mo, SD 1y 3mo) completed assessments of reading comprehension, listening comprehension, word/non-word reading, speech articulation, and Non-verbal IQ. RESULTS: Reading comprehension and word reading were worse in children with rolandic epilepsy (F1,61 =6.89, p=0.011, ηp2=0.10 and F1,61 =6.84, p=0.011, ηp2=0.10 respectively), with listening comprehension being marginal (F1,61 =3.81, p=0.055, ηp2=0.06). Word reading and listening comprehension made large and independent contributions to reading comprehension, explaining 70% of the variance. INTERPRETATION: Children with rolandic epilepsy may be at risk of reading comprehension difficulties. Thorough assessment of individual children is required to ascertain whether the difficulties lie with decoding text, or with general comprehension skills, or both. WHAT THIS PAPER ADDS: Children with rolandic epilepsy may be at risk of poor reading comprehension. This was related to poor word reading, poor listening comprehension, or both. Reading comprehension interventions should be tailored to the profile of difficulties.


Asunto(s)
Trastornos del Conocimiento/etiología , Comprensión/fisiología , Dislexia/etiología , Epilepsia Rolándica/complicaciones , Epilepsia Rolándica/psicología , Estimulación Acústica , Análisis de Varianza , Niño , Trastornos del Conocimiento/diagnóstico , Estudios Transversales , Dislexia/diagnóstico , Femenino , Humanos , Pruebas del Lenguaje , Masculino , Estudios Retrospectivos
19.
Clin Psychol Psychother ; 25(3): 440-445, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29446195

RESUMEN

We examine associations between client attachment style and therapeutic alliance in a 3-arm randomized controlled trial of brief motivational interviewing and cognitive-behavioural therapy compared with longer term motivational interviewing and cognitive-behavioural therapy or standard care alone. Client self-report measures of attachment style were completed at baseline, and both clients and therapists in the treatment arms of the trial completed alliance measures 1 month into therapy. We found that insecure-anxious attachment was positively associated with therapist-rated alliance, whereas clients with insecure-avoidant attachment were more likely to report poorer bond with therapist. There was no evidence that client attachment significantly predicted clinical or substance misuse outcomes either directly or indirectly via alliance. Nor evidence that the length of therapy offered interacted with attachment to predict alliance.


Asunto(s)
Uso de la Marihuana/psicología , Apego a Objetos , Relaciones Profesional-Paciente , Psicoterapia/métodos , Trastornos Psicóticos/terapia , Adulto , Terapia Cognitivo-Conductual , Femenino , Humanos , Masculino , Entrevista Motivacional , Psicoterapia Breve , Trastornos Psicóticos/psicología , Adulto Joven
20.
PLoS Med ; 14(1): e1002221, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28118352

RESUMEN

BACKGROUND: It has been suggested that greater maternal adiposity during pregnancy affects lifelong risk of offspring fatness via intrauterine mechanisms. Our aim was to use Mendelian randomisation (MR) to investigate the causal effect of intrauterine exposure to greater maternal body mass index (BMI) on offspring BMI and fat mass from childhood to early adulthood. METHODS AND FINDINGS: We used maternal genetic variants as instrumental variables (IVs) to test the causal effect of maternal BMI in pregnancy on offspring fatness (BMI and dual-energy X-ray absorptiometry [DXA] determined fat mass index [FMI]) in a MR approach. This was investigated, with repeat measurements, from ages 7 to 18 in the Avon Longitudinal Study of Parents and Children (ALSPAC; n = 2,521 to 3,720 for different ages). We then sought to replicate findings with results for BMI at age 6 in Generation R (n = 2,337 for replication sample; n = 6,057 for total pooled sample). In confounder-adjusted multivariable regression in ALSPAC, a 1 standard deviation (SD, equivalent of 3.7 kg/m2) increase in maternal BMI was associated with a 0.25 SD (95% CI 0.21-0.29) increase in offspring BMI at age 7, with similar results at later ages and when FMI was used as the outcome. A weighted genetic risk score was generated from 32 genetic variants robustly associated with BMI (minimum F-statistic = 45 in ALSPAC). The MR results using this genetic risk score as an IV in ALSPAC were close to the null at all ages (e.g., 0.04 SD (95% CI -0.21-0.30) at age 7 and 0.03 SD (95% CI -0.26-0.32) at age 18 per SD increase in maternal BMI), which was similar when a 97 variant generic risk score was used in ALSPAC. When findings from age 7 in ALSPAC were meta-analysed with those from age 6 in Generation R, the pooled confounder-adjusted multivariable regression association was 0.22 SD (95% CI 0.19-0.25) per SD increase in maternal BMI and the pooled MR effect (pooling the 97 variant score results from ALSPAC with the 32 variant score results from Generation R) was 0.05 SD (95%CI -0.11-0.21) per SD increase in maternal BMI (p-value for difference between the two results = 0.05). A number of sensitivity analyses exploring violation of the MR results supported our main findings. However, power was limited for some of the sensitivity tests and further studies with relevant data on maternal, offspring, and paternal genotype are required to obtain more precise (and unbiased) causal estimates. CONCLUSIONS: Our findings provide little evidence to support a strong causal intrauterine effect of incrementally greater maternal BMI resulting in greater offspring adiposity.


Asunto(s)
Adiposidad/genética , Índice de Masa Corporal , Variación Genética , Absorciometría de Fotón , Adolescente , Niño , Inglaterra , Femenino , Humanos , Estudios Longitudinales , Masculino , Análisis de la Aleatorización Mendeliana , Análisis Multivariante , Embarazo , Análisis de Regresión
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