The causal effects of education on adult health, mortality and income: evidence from Mendelian randomization and the raising of the school leaving age

We conducted a genome-wide association study (GWAS) on income among individuals of European descent and leveraged the results to investigate the socio-economic health gradient (N= 668,288). We found 162 genomic loci associated with a common genetic factor underlying various income measures, all with small effect sizes. Our GWAS-derived polygenic index captures 1-4% of income variance, with only one-fourth attributed to direct genetic effects. A phenome-wide association study using this polygenic index showed reduced risks for a broad spectrum of diseases, including hypertension, obesity, type 2 diabetes, coronary atherosclerosis, depression, asthma, and back pain. The income factor showed a substantial genetic correlation (0.92, se=. 006) with educational attainment (EA). Accounting for EA's genetic overlap with income revealed that the remaining genetic signal for higher income related to better mental health but reduced physical health benefits and increased participation in risky behaviours such as drinking and smoking.

Communications Biology

Risk behaviours are common in adolescent and persist into adulthood, people who engage in more risk behaviours are more likely to have lower educational attainment. We applied genetic causal inference methods to explore the causal relationship between adolescent risk behaviours and educational achievement. Risk behaviours were phenotypically associated with educational achievement at age 16 after adjusting for confounders (−0.11, 95%CI: −0.11, −0.09). Genomic-based restricted maximum likelihood (GREML) results indicated that both traits were heritable and have a shared genetic architecture (Risk \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{{{{{\boldsymbol{h …

This paper contributes to the literature on the earnings returns to university graduation. Recent evidence using administrative earnings data from England suggests a zero return to graduation for men and positive returns to graduation for women in annual earnings at age 26. We show that once hours worked are taken into account-typically not available in administrative tax data-returns to graduation are zero for women too. Graduate women work more hours than comparable non-graduate women, explaining their annual earnings return, but in terms of hourly wages, average returns to graduation at this early career stage are around zero for both sexes. This highlights the importance of using both survey and administrative data sources when estimating the returns to university graduation.

BMC medicine

BackgroundThe timing of puberty may have an important impact on adolescent mental health. In particular, earlier age at menarche has been associated with elevated rates of depression in adolescents. Previous research suggests that this relationship may be causal, but replication and an investigation of whether this effect extends to other mental health domains is warranted.MethodsIn this Registered Report, we triangulated evidence from different causal inference methods using a new wave of data (N= 13,398) from the Norwegian Mother, Father, and Child Cohort Study. We combined multiple regression, one-and two-sample Mendelian randomisation (MR), and negative control analyses (using pre-pubertal symptoms as outcomes) to assess the causal links between age at menarche and different domains of adolescent mental health.ResultsOur results supported the hypothesis that earlier age at menarche is …

Journal of the Royal Statistical Society Series B: Statistical Methodology

We discuss the fundamental issue of identification in linear instrumental variable (IV) models with unknown IV validity. With the assumption of the ‘sparsest rule’, which is equivalent to the plurality rule but becomes operational in computation algorithms, we investigate and prove the advantages of non-convex penalized approaches over other IV estimators based on two-step selections, in terms of selection consistency and accommodation for individually weak IVs. Furthermore, we propose a surrogate sparsest penalty that aligns with the identification condition and provides oracle sparse structure simultaneously. Desirable theoretical properties are derived for the proposed estimator with weaker IV strength conditions compared to the previous literature. Finite sample properties are demonstrated using simulations and the selection and estimation method is applied to an empirical study concerning the effect of …

Journal of Neurology, Neurosurgery & Psychiatry

Understanding the causes of Alzheimer’s disease and related dementias remains a challenge. Observational studies investigating dementia risk factors are limited by the pervasive issues of confounding, reverse causation and selection biases. Conducting randomised controlled trials for dementia prevention is often impractical due to the long prodromal phase and the inability to randomise many potential risk factors. In this essay, we introduce Mendelian randomisation as an alternative approach to examine factors that may prevent or delay Alzheimer’s disease. Mendelian randomisation is a causal inference method that has successfully identified risk factors and treatments in various other fields. However, applying this method to dementia risk factors has yielded unexpected findings. Here, we consider five potential explanations and provide recommendations to enhance causal inference from Mendelian …

Journal of Affective Disorders

BackgroundParticipation in higher education has significant and long-lasting consequences for people's socioeconomic trajectories. Maternal depression is linked to poorer educational achievement for children in school, but its impact on university attendance is unclear.MethodsIn an English longitudinal cohort study (N = 8952), we explore whether young people whose mothers experienced elevated depressive symptoms are less likely to attend university, and the role of potential mediators in the young person: educational achievement in school, depressive symptoms, and locus of control. We also examine whether maternal depressive symptoms influence young people's choice of university, and non-attendees' reasons for not participating in higher education.ResultsYoung people whose mothers experienced more recurrent depressive symptoms were less likely to attend university (OR = 0.88, CI = 0.82,0.94, p < …

medRxiv

Background Children with obesity are more likely to have parents with obesity, too. Several environmental explanations have been proposed for this correlation, including foetal programming, and parenting practices. However, body mass index (BMI) is a highly heritable trait; child-parent correlations may reflect direct inheritance of adiposity-related genes. There is some evidence that mother's BMI associates with offspring BMI net of direct genetic inheritance, consistent with both intrauterine and parenting effects, but this requires replication. Here we also investigate the role of father's BMI and diet as a mediating parenting factor. Methods We used Mendelian Randomization (MR) with genetic trio (mother-father-offspring) data from 2,621 families in the Millennium Cohort Study, a UK birth cohort study of individuals born in 2001/02, to examine the association between parental BMI (kg/m2) and offspring birthweight and BMI and diet measured at six-time points between ages 3y and 17y. Paternal and maternal BMI were instrumented with polygenic indices (PGI) for BMI also conditioning upon offspring PGI. This allowed us to separate direct and indirect ("genetic nurture") genetic effects. We compared these results with associations obtained using multivariable regression techniques using phenotypic BMI data only, the standard research approach. Results Mother's and father's BMI were positively associated with offspring BMI to similar degrees. However, in MR analysis, associations between father's BMI and offspring BMI were close to the null, suggesting phenotypic associations reflect the direct transmission of genetic traits. In contrast, mother's …

Journal of Psychiatric Research

Treatment response is hard to predict and detailed mechanisms unknown. Lower levels of the dehydroepiandrosterone sulphate (DHEA(S)) – a precursor to testosterone and estrogen – have been associated to depression and to response to antidepressant treatment. Previous studies however may have been ridden by confounding and reverse causation. The aim of this study is to evaluate whether higher levels of DHEA(S) are causally linked to response to antidepressants using mendelian randomization (MR). We performed a Two-sample MR analysis using data the largest publicly available GWAS of DHEA(S) levels (n = 14,846) using eight common genetic variants associated to DHEA(S) (seven single nucleotide polymorphisms and one variant rs2497306) and the largest GWAS of antidepressant response (n = 5218) using various MR methods (IVW, MR Egger, Weighted mean, weighted mode, MR …

General Psychiatry

Background Psychiatric comorbidities are common in patients with epilepsy. Reasons for the co-occurrence of psychiatric conditions and epilepsy remain poorly understood. Aim We aimed to triangulate the relationship between epilepsy and psychiatric conditions to determine the extent and possible origins of these conditions. Methods Using nationwide Swedish health registries, we quantified the lifetime prevalence of psychiatric disorders in patients with epilepsy. We then used summary data from genome-wide association studies to investigate whether the identified observational associations could be attributed to a shared underlying genetic aetiology using cross-trait linkage disequilibrium score regression. Finally, we assessed the potential bidirectional relationships using two-sample Mendelian randomisation. Results In a cohort of 7 628 495 individuals, we found that almost half of the 94 435 individuals diagnosed with epilepsy were also diagnosed with a psychiatric condition in their lifetime (adjusted lifetime prevalence, 44.09%; 95% confidence interval (CI) 43.78% to 44.39%). We found evidence for a genetic correlation between epilepsy and some neurodevelopmental and psychiatric conditions. For example, we observed a genetic correlation between epilepsy and attention-deficit/hyperactivity disorder (rg =0.18, 95% CI 0.09 to 0.27, p<0.001)—a correlation that was more pronounced in focal epilepsy (rg =0.23, 95% CI 0.09 to 0.36, p<0.001). Findings from Mendelian randomisation using common genetic variants did not support bidirectional effects between epilepsy and neurodevelopmental or psychiatric conditions. Conclusions …

BackgroundResearchers are increasingly expected to draw policy implications from their research, yet this can be distracting or misleading when describing single studies. Rather than helping ensure that research benefits society, it may distort research and evidence-based policy. This is propelled by incentives such as career structures increasingly favoring evidence of ‘impact’and a need to appeal to competitive publication and funding decisions. We discuss this issue, use an example from the health inequality literature to highlight the complications of drawing policy conclusions, and consider options to improve both research and evidence-based policy making.

Health Economics

We study the effect of economic conditions early in life on the occurrence of type‐2 diabetes in adulthood using contextual economic indicators and within‐sibling pair variation. We use data from Lifelines: a longitudinal cohort study and biobank including 51,270 siblings born in the Netherlands from 1950 onward. Sibling fixed‐effects account for selective fertility. To identify type‐2 diabetes we use biomarkers on the hemoglobin A1c concentration and fasting glucose in the blood. We find that adverse economic conditions around birth increase the probability of type‐2 diabetes later in life both in males and in females. Inference based on self‐reported diabetes leads to biased results, incorrectly suggesting the absence of an effect. The same applies to inference that does not account for selective fertility.

BJOG: An International Journal of Obstetrics & Gynaecology

Objective To examine antiseizure medication (ASM) prescription during pregnancy. Design Population‐based drug utilisation study. Setting UK primary and secondary care data, 1995–2018, from the Clinical Practice Research Datalink GOLD version. Population or Sample 752 112 completed pregnancies among women registered for a minimum of 12 months with an ‘up to standard’ general practice prior to the estimated start of pregnancy and for the duration of their pregnancy. Methods We described ASM prescription across the study period, overall and by ASM indication, examined patterns of prescription during pregnancy including continuous prescription and discontinuation, and used logistic regression to investigate factors associated with those ASM prescription patterns. Main Outcome Measures Prescription of ASMs during pregnancy and discontinuation of ASMs before and during pregnancy …

Genome biology

BackgroundPubertal growth patterns correlate with future health outcomes. However, the genetic mechanisms mediating growth trajectories remain largely unknown. Here, we modeled longitudinal height growth with Super-Imposition by Translation And Rotation (SITAR) growth curve analysis on ~ 56,000 trans-ancestry samples with repeated height measurements from age 5 years to adulthood. We performed genetic analysis on six phenotypes representing the magnitude, timing, and intensity of the pubertal growth spurt. To investigate the lifelong impact of genetic variants associated with pubertal growth trajectories, we performed genetic correlation analyses and phenome-wide association studies in the Penn Medicine BioBank and the UK Biobank.ResultsLarge-scale growth modeling enables an unprecedented view of adolescent growth across contemporary and 20th-century pediatric cohorts. We identify …

Journal of Neurology, Neurosurgery & Psychiatry

Background Alzheimer’s disease (AD)-related neuropathological changes can occur decades before clinical symptoms. We aimed to investigate whether neurodevelopment and/or neurodegeneration affects the risk of AD, through reducing structural brain reserve and/or increasing brain atrophy, respectively.Methods We used bidirectional two-sample Mendelian randomisation to estimate the effects between genetic liability to AD and global and regional cortical thickness, estimated total intracranial volume, volume of subcortical structures and total white matter in 37 680 participants aged 8–81 years across 5 independent cohorts (Adolescent Brain Cognitive Development, Generation R, IMAGEN, Avon Longitudinal Study of Parents and Children and UK Biobank). We also examined the effects of global and regional cortical thickness and subcortical volumes from the Enhancing NeuroImaging Genetics through …

The Lancet Child & Adolescent Health

BackgroundPaediatric multisystem inflammatory syndrome temporally associated with SARS-CoV-2 (PIMS-TS), also known as multisystem inflammatory syndrome in children (MIS-C) emerged in April, 2020. The paediatric comparisons within the RECOVERY trial aimed to assess the effect of intravenous immunoglobulin or corticosteroids compared with usual care on duration of hospital stay for children with PIMS-TS and to compare tocilizumab (anti-IL-6 receptor monoclonal antibody) or anakinra (anti-IL-1 receptor antagonist) with usual care for those with inflammation refractory to initial treatment.MethodsWe did this randomised, controlled, open-label, platform trial in 51 hospitals in the UK. Eligible patients were younger than 18 years and had been admitted to hospital for PIMS-TS. In the first randomisation, patients were randomly assigned (1: 1: 1) to usual care (no additional treatments), usual care plus …

Behavioral & Brain Sciences

When building causal knowledge in behavioural genetics, the natural randomisation of genotypes at conception (approximately analogous to the artificial randomisation occurring in randomised controlled trials) facilitates the discovery of genetic causes. More importantly, the randomisation of genetic material within families also enables a better identification of (environmental) risk factors and aetiological pathways to diseases and behaviours.

Molecular Psychiatry

Identifying mechanisms underlying the intergenerational transmission of risk for attention-deficit/hyperactivity disorder (ADHD) traits can inform interventions and provide insights into the role of parents in shaping their children’s outcomes. We investigated whether genetic transmission and genetic nurture (environmentally mediated effects) underlie associations between polygenic scores indexing parental risk and protective factors and their offspring’s ADHD traits. This birth cohort study included 19,506 genotyped mother-father-offspring trios from the Norwegian Mother, Father and Child Cohort Study. Polygenic scores were calculated for parental factors previously associated with ADHD, including psychopathology, substance use, neuroticism, educational attainment, and cognitive performance. Mothers reported on their 8-year-old children’s ADHD traits (n = 9,454 children) using the Parent/Teacher Rating …

Risk behaviours such as alcohol use, smoking, and physical inactivity are common in adolescence and persist into adulthood. People who engage in more risk behaviour are more likely to have lower educational attainment. Genome-wide association studies show that participation in risk behaviours and level of education are both heritable and have a highly polygenic architecture, suggesting an important role of many variants across the genome. The extent to which risk behaviours and educational attainment have shared genetic overlap is unknown, yet knowledge of this could help understand how these traits co-occur and influence each other. In the ALSPAC cohort, we used genome-based restricted maximum likelihood (GREML) to estimate the genetic covariance between risk behaviours and educational achievement. We found a strong genetic component of educational achievement and a modest genetic component of the risk behaviours. Whereby children who have a higher genetic liability for education also have a lower genetic liability for risky behaviours.

International Journal of Population Data Science

The negative relationship between education and crime is well documented for many countries. In England, continued participation in education beyond the compulsory minimum school leaving age of 16 is strongly associated with a lower probability of experiencing custody in later teenage years, however the non-random selection of young people into continued participation means cross-sectional estimates of the relationship are likely to contain considerable bias. This paper estimates the causal effect of continuing in education post-16 on the probability of experiencing youth custody at ages 17 and 18, addressing the endogeneity of continued participation by exploiting the natural experiment created by the ‘raising of the participation age’in England in 2012/13. Unlike previous cohorts who could leave education aged 16, young people starting the final year of compulsory schooling in September 2012 were required to remain in education or training until the end of the school year in which they turned 17, and those starting the final year in September 2013 were required to remain in education or training until age 18. Using this exogenous variation in participation between cohorts we estimate the causal effect of continued participation on custody outcomes at ages 17 and 18 using Two-Stage Least Squares and Regression Discontinuity methods. The effect of the law change was to increase the proportion of young people participating in education at age 17 by 1.7 pp (1.2 pp) for boys (girls), from a base of 82.1%(85.0%) immediately prior to the reform. Despite this increase in participation, there was no identified effect on the probability of …

International Journal of Epidemiology

The 2015 Pelotas (Brazil) Birth Cohort is a prospective study of all children born between 1 January and 31 December 2015 to women living in Pelotas city. 1 Pelotas is a relatively poor city in Southern Brazil; see Table 1 for comparisons between Pelotas and Brazil on several socioeconomic indicators, infant mortality rates and violence. The 2015 cohort is the fourth in a series of similar cohort studies in Pelotas, which included children born in 1982, 1993 and 2004. The 2015 cohort was the first to include an assessment during pregnancy. The original aims were to investigate early life exposures for health outcomes, with special attention to physical activity and social inequalities. The original cohort profile 1 described follow-ups in pregnancy, at birth and at ages 3 and 12 months. Two nested randomized trials of an exercise intervention in pregnancy 2 and an infant-sleep intervention 3 were also described.

International Journal of Epidemiology

Background Many observational studies support light-to-moderate alcohol intake as potentially protective against premature death. We used a genetic approach to evaluate the linear and nonlinear relationships between alcohol consumption and mortality from different underlying causes. Methods We used data from 278 093 white-British UK Biobank participants, aged 37–73 years at recruitment and with data on alcohol intake, genetic variants, and mortality. Habitual alcohol consumption was instrumented by 94 variants. Linear Mendelian randomization (MR) analyses were conducted using five complementary approaches, and nonlinear MR analyses by the doubly-ranked method. Results There were 20 834 deaths during the follow-up (median 12.6 years). In conventional analysis, the association between alcohol consumption and mortality …

International Journal of Epidemiology

To date, there have been> 750 million reported cases of COVID-19 globally since the pandemic began in early 2020. 1 In the UK, there have been> 1 million patients hospitalized and 180000 deaths due to COVID-19. 2 Previous viral epidemics and conditions causing acute respiratory distress syndrome caused long-lasting health impacts on the affected survivors. 3, 4 At the time of conception of the Post-Hospitalisation COVID-19 (PHOSP-COVID) cohort in March 2020, the longer-term pulmonary and multisystem effects of COVID-19 and impact on health status were unknown. 5 We identified a need to establish a cohort of hospitalized COVID-19 survivors to collect detailed information about the medium-and long-term effects of COVID-19 on physical and mental health, lifestyle and occupation status.Although the majority of individuals with COVID-19 were not hospitalized, we expected that the consequences of …

International Journal of Epidemiology

To date, there have been> 750 million reported cases of COVID-19 globally since the pandemic began in early 2020. 1 In the UK, there have been> 1 million patients hospitalized and 180000 deaths due to COVID-19. 2 Previous viral epidemics and conditions causing acute respiratory distress syndrome caused long-lasting health impacts on the affected survivors. 3, 4 At the time of conception of the Post-Hospitalisation COVID-19 (PHOSP-COVID) cohort in March 2020, the longer-term pulmonary and multisystem effects of COVID-19 and impact on health status were unknown. 5 We identified a need to establish a cohort of hospitalized COVID-19 survivors to collect detailed information about the medium-and long-term effects of COVID-19 on physical and mental health, lifestyle and occupation status.Although the majority of individuals with COVID-19 were not hospitalized, we expected that the consequences of …

International Journal of Epidemiology

Background Over 120 million people in the USA live in areas with unsafe ozone (O3) levels. Studies among adults have linked exposure to worse lung function and higher risk of asthma and chronic obstructive pulmonary disease (COPD). However, few studies have examined the effects of O3 in children, and existing studies are limited in terms of their geographic scope or outcomes considered. Methods We leveraged a dataset of encounters at 42 US children’s hospitals from 2004–2015. We used a one-stage case-crossover design to quantify the association between daily maximum 8-hour O3 in the county in which the hospital is located and risk of emergency department (ED) visits for any cause and for respiratory disorders, asthma, respiratory infections, allergies and ear disorders. Results Approximately 28 million visits were available during this period …

International Journal of Epidemiology

To date, there have been> 750 million reported cases of COVID-19 globally since the pandemic began in early 2020. 1 In the UK, there have been> 1 million patients hospitalized and 180000 deaths due to COVID-19. 2 Previous viral epidemics and conditions causing acute respiratory distress syndrome caused long-lasting health impacts on the affected survivors. 3, 4 At the time of conception of the Post-Hospitalisation COVID-19 (PHOSP-COVID) cohort in March 2020, the longer-term pulmonary and multisystem effects of COVID-19 and impact on health status were unknown. 5 We identified a need to establish a cohort of hospitalized COVID-19 survivors to collect detailed information about the medium-and long-term effects of COVID-19 on physical and mental health, lifestyle and occupation status.Although the majority of individuals with COVID-19 were not hospitalized, we expected that the consequences of …

International Journal of Epidemiology

Qualitative research and mixed methods are core competencies for epidemiologists. In response to the shortage of guidance on graduate course development, we wrote a course development guide aimed at faculty and students designing similar courses in epidemiology curricula. The guide combines established educational theory with faculty and student experiences from a recent introductory course for epidemiology and biostatistics doctoral students at the University of Zurich and Swiss Federal Institute of Technology, Zurich. We propose a student-centred course with inverse classroom teaching and practice exercises with faculty input. Integration of student input during the course development process helps align the course syllabus with student needs. The proposed course comprises six sessions that cover learning outcomes in comprehension, knowledge, application, analysis, synthesis and evaluation …

International Journal of Epidemiology

Background Depressive symptoms are common in knee osteoarthritis (OA), exacerbate knee pain severity and may influence outcomes of oral analgesic treatments. The aim was to assess whether oral analgesic effectiveness in knee OA varies by fluctuations in depressive symptoms. Methods The sample included Osteoarthritis Initiative (OAI) participants not treated with oral analgesics at enrolment (n = 1477), with radiographic disease at the first follow-up visit (defined as the index date). Oral analgesic treatment and depressive symptoms, assessed with the Center for Epidemiological Studies Depression [(CES-D) score ≥16] Scale, were measured over three annual visits. Knee pain severity was measured at visits adjacent to treatment and modifier using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale (rescaled range = 0–100 …

International Journal of Epidemiology

The purpose of establishing the Mothers and Newborns (MN) Cohort under the auspices of the Columbia Center for Children’s Environmental Health (CCCEH) was to create a longitudinal birth cohort study that would further the understanding of prenatal and early-life environmental exposures on children’s health outcomes. We specifically wanted to look at these associations in minority populations who are under-represented in research. 1 With this data collection, we intended to further the science of exposure to environmental toxicants on health outcomes including neurodevelopment, asthma and obesity, as well as to inform policy makers of these associations and opportunities to intervene.Women in the MN cohort were recruited from March 1998 through to August 2006 at prenatal ambulatory care clinics of New York Presbyterian Medical Center or Harlem Hospital. These clinics provided care for women who …

International Journal of Epidemiology

To date, there have been> 750 million reported cases of COVID-19 globally since the pandemic began in early 2020. 1 In the UK, there have been> 1 million patients hospitalized and 180000 deaths due to COVID-19. 2 Previous viral epidemics and conditions causing acute respiratory distress syndrome caused long-lasting health impacts on the affected survivors. 3, 4 At the time of conception of the Post-Hospitalisation COVID-19 (PHOSP-COVID) cohort in March 2020, the longer-term pulmonary and multisystem effects of COVID-19 and impact on health status were unknown. 5 We identified a need to establish a cohort of hospitalized COVID-19 survivors to collect detailed information about the medium-and long-term effects of COVID-19 on physical and mental health, lifestyle and occupation status.Although the majority of individuals with COVID-19 were not hospitalized, we expected that the consequences of …

International Journal of Epidemiology

Background Culture-independent diagnostic testing (CIDT) provides rapid results to clinicians and is quickly displacing traditional detection methods. Increased CIDT use and sensitivity likely result in higher case detection but might also obscure infection trends. Severe illness outcomes, such as hospitalization and death, are likely less affected by changes in testing practices and can be used as indicators of the expected case incidence trend had testing methods not changed. Methods Using US Foodborne Diseases Active Surveillance Network data during 1996–2019 and mixed effects quasi-Poisson regression, we estimated the expected yearly incidence for nine enteric pathogens. Results Removing the effect of CIDT use, CIDT panel testing and culture-confirmation of CIDT testing, the modelled incidence in all but three pathogens (Salmonella, Shigella …

International Journal of Epidemiology

Background Congenital hearing loss (HL), one of the most common paediatric chronic conditions, significantly affects speech and language development. Its early diagnosis and medical intervention can be achieved via newborn hearing screening. However, data on the prevalence and aetiology of congenital HL in infants who fail newborn hearing screening are limited. Methods The sample population included 153 913 infants who underwent newborn hearing screening, and the prevalence of congenital HL, defined as moderate to profound bilateral HL (BHL) or unilateral HL (UHL) (≥40 dB HL), in one prefecture of Japan was measured to minimize the loss-to-follow-up rate, a common factor affecting the screening procedure. Comprehensive aetiological investigation, including physiology, imaging, genetic tests, and congenital cytomegalovirus screening, was performed on …

International Journal of Epidemiology

The purpose of establishing the Mothers and Newborns (MN) Cohort under the auspices of the Columbia Center for Children’s Environmental Health (CCCEH) was to create a longitudinal birth cohort study that would further the understanding of prenatal and early-life environmental exposures on children’s health outcomes. We specifically wanted to look at these associations in minority populations who are under-represented in research. 1 With this data collection, we intended to further the science of exposure to environmental toxicants on health outcomes including neurodevelopment, asthma and obesity, as well as to inform policy makers of these associations and opportunities to intervene.Women in the MN cohort were recruited from March 1998 through to August 2006 at prenatal ambulatory care clinics of New York Presbyterian Medical Center or Harlem Hospital. These clinics provided care for women who …

International Journal of Epidemiology

Background Over 120 million people in the USA live in areas with unsafe ozone (O3) levels. Studies among adults have linked exposure to worse lung function and higher risk of asthma and chronic obstructive pulmonary disease (COPD). However, few studies have examined the effects of O3 in children, and existing studies are limited in terms of their geographic scope or outcomes considered. Methods We leveraged a dataset of encounters at 42 US children’s hospitals from 2004–2015. We used a one-stage case-crossover design to quantify the association between daily maximum 8-hour O3 in the county in which the hospital is located and risk of emergency department (ED) visits for any cause and for respiratory disorders, asthma, respiratory infections, allergies and ear disorders. Results Approximately 28 million visits were available during this period …

International Journal of Epidemiology

Data from a single study are rarely sufficient to comprehensively understand a phenomenon of interest or to build predictive models with statistical power. Meta-analyses, including aggregated data for several cohort studies, can be carried out to synthesize published results, but the use of harmonized individual-level data from different studies is preferable to reach the maximal comparability across the studies. A significant barrier to the co-analysis approach is finding relevant studies and accessing their data.Such barriers have, amongst others, led to designing the FAIR (Findable, Accessible, Interoperable and Reusable) principles, which have been recognized internationally. 1 Currently, it is still difficult to obtain a comprehensive overview of available data from existing observational studies on cardiovascular diseases. Because there is no requirement to register studies other than clinical trials, information on …

International Journal of Epidemiology

Background In settings with large case detection gaps, active case-finding (ACF) may play a critical role in the uberculosis (TB) response. However, ACF is resource intensive, and its effectiveness depends on whether people detected with TB through ACF might otherwise spontaneously resolve or be diagnosed through routine care. We analysed the potential effectiveness of ACF for TB relative to the counterfactual scenario of routine care alone. Methods We constructed a Markov simulation model of TB natural history, diagnosis, symptoms, ACF and treatment, using a hypothetical reference setting using data from South East Asian countries. We calibrated the model to empirical data using Bayesian methods, and simulated potential 5-year outcomes with an ‘aspirational’ ACF intervention (reflecting maximum possible effectiveness) compared with the standard-of-care outcomes …

International Journal of Epidemiology

Data from a single study are rarely sufficient to comprehensively understand a phenomenon of interest or to build predictive models with statistical power. Meta-analyses, including aggregated data for several cohort studies, can be carried out to synthesize published results, but the use of harmonized individual-level data from different studies is preferable to reach the maximal comparability across the studies. A significant barrier to the co-analysis approach is finding relevant studies and accessing their data.Such barriers have, amongst others, led to designing the FAIR (Findable, Accessible, Interoperable and Reusable) principles, which have been recognized internationally. 1 Currently, it is still difficult to obtain a comprehensive overview of available data from existing observational studies on cardiovascular diseases. Because there is no requirement to register studies other than clinical trials, information on …

International Journal of Epidemiology

Background The incidence of differentiated thyroid cancer (DTC) is higher in women than in men but whether sex steroid hormones contribute to this difference remains unclear. Studies of reproductive and hormonal factors and thyroid cancer risk have provided inconsistent results. Methods Original data from 1 252 907 women in 16 cohorts in North America, Europe, Australia and Asia were combined to evaluate associations of DTC risk with reproductive and hormonal factors. Multivariable-adjusted Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% CIs. Results During follow-up, 2142 women were diagnosed with DTC. Factors associated with higher risk of DTC included younger age at menarche (<10 vs 10–11 years; HR, 1.28; 95% CI, 1.00–1.64), younger (<40; HR, 1.31; 95% CI, 1.05–1.62) and older (≥55; HR, 1.33 …

International Journal of Epidemiology

Background Frequent fruit and vegetable consumption is considered a promising dietary behaviour that protects health. However, most existing studies about the factors associated with this phenomenon among Africans are based on single-country reports, apart from one meta-regression combining smaller studies. This study harmonized large datasets and assessed factors associated with the frequency of fruit and vegetable consumption in this population. Methods Individual-level data on sociodemographics, lifestyle and diet from 20 443 participants across five African countries (Burkina Faso, Ghana, Kenya, South Africa and Nigeria), from the Stroke Investigative Research and Educational Network (SIREN) and Africa Wits-INDEPTH partnership for Genomic Research (AWI-Gen) studies, were harmonized. Total frequency of fruit and vegetable consumption (in portions/week …

International Journal of Epidemiology

Background Sustainable dietary patterns that incorporate multiple dimensions may have benefits for both human health and the environment. We examined the association between sustainable dietary patterns assessed by using the Sustainable Diet Index-US (SDI-US) and mortality in US adults. Methods This study used data from the National Health and Nutrition Examination Survey 2007–18 (N = 22 414 aged ≥20 years). The SDI-US (range: 4–20) was composed of four sub-indices representing nutritional, environmental, economic and sociocultural dimensions, and was computed using 24-h dietary recalls, food expenditures and food preparation habits. A higher score indicates a more sustainable dietary pattern. All-cause mortality from baseline until 31 December 2019 was obtained through linkage to the National Death Index. Hazard ratios (HRs) with 95% CIs were …