Objective: To examine the relations between obesity or overweight and coronary heart disease (CHD) mortality in men with and without prevalent CHD in a prospective cohort study.Methods: In the Whitehall study of London-based male government employees, 18403 middle age men were followed up for a maximum of 35 years having participated in a medical examination in the late 1960s in which weight, height, CHD status, and a range of other social, physiological, and behavioural characteristics were measured.Results: In age-adjusted analyses of men with baseline CHD there was a modest raised risk in the overweight relative to normal weight groups for all cause mortality (hazard ratio 1.10, 95% confidence interval (CI) 1.00 to 1.20) and CHD mortality (1.28, 95% CI 1.11 to 1.47) but not for stroke mortality (1.01, 95% CI 0.73 to 1.40). Mortality was similarly raised in the obese group. While these slopes were much steeper in men who were apparently CHD-free at study induction, the difference in the gradients according to baseline CHD status did not attain significance at conventional levels (p value for interaction >= 0.24). The weight-mortality relations were somewhat attenuated when potential mediating and confounding factors were added to the multivariable models in both men with and men without a history of CHD.Conclusions: Avoidance of obesity and overweight in adult life in men with and without CHD may reduce their later risk of total and CHD mortality.
Background Several studies have shown that diabetes confers a higher relative risk of vascular mortality among women than among men, but whether this increased relative risk in women exists across age groups and within defined levels of other risk factors is uncertain. We aimed to determine whether differences in established risk factors, such as blood pressure, BMI, smoking, and cholesterol, explain the higher relative risks of vascular mortality among women than among men. Methods In our meta-analysis, we obtained individual participant-level data from studies included in the Prospective Studies Collaboration and the Asia Pacific Cohort Studies Collaboration that had obtained baseline information on age, sex, diabetes, total cholesterol, blood pressure, tobacco use, height, and weight. Data on causes of death were obtained from medical death certificates. We used Cox regression models to assess the relevance of diabetes (any type) to occlusive vascular mortality (ischaemic heart disease, ischaemic stroke, or other atherosclerotic deaths) by age, sex, and other major vascular risk factors, and to assess whether the associations of blood pressure, total cholesterol, and body-mass index (BMI) to occlusive vascular mortality are modified by diabetes. Results Individual participant-level data were analysed from 980 793 adults. During 9·8 million person-years of follow-up, among participants aged between 35 and 89 years, 19 686 (25·6%) of 76 965 deaths were attributed to occlusive vascular disease. After controlling for major vascular risk factors, diabetes roughly doubled occlusive vascular mortality risk among men (death rate ratio [RR] 2·10, 95% CI 1·97–2·24) and tripled risk among women (3·00, 2·71–3·33; χ2 test for heterogeneity p<0·0001). For both sexes combined, the occlusive vascular death RRs were higher in younger individuals (aged 35–59 years: 2·60, 2·30–2·94) than in older individuals (aged 70–89 years: 2·01, 1·85–2·19; p=0·0001 for trend across age groups), and, across age groups, the death RRs were higher among women than among men. Therefore, women aged 35–59 years had the highest death RR across all age and sex groups (5·55, 4·15–7·44). However, since underlying confounder-adjusted occlusive vascular mortality rates at any age were higher in men than in women, the adjusted absolute excess occlusive vascular mortality associated with diabetes was similar for men and women. At ages 35–59 years, the excess absolute risk was 0·05% (95% CI 0·03–0·07) per year in women compared with 0·08% (0·05–0·10) per year in men; the corresponding excess at ages 70–89 years was 1·08% (0·84–1·32) per year in women and 0·91% (0·77–1·05) per year in men. Total cholesterol, blood pressure, and BMI each showed continuous log-linear associations with occlusive vascular mortality that were similar among individuals with and without diabetes across both sexes. Interpretation Independent of other major vascular risk factors, diabetes substantially increased vascular risk in both men and women. Lifestyle changes to reduce smoking and obesity and use of cost-effective drugs that target major vascular risks (eg, statins and antihypertensive drugs) are important in both men and women with diabetes, but might not reduce the relative excess risk of occlusive vascular disease in women with diabetes, which remains unexplained. Funding UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union BIOMED programme, and National Institute on Aging (US National Institutes of Health).
This is the final version. Available on open access from Nature Research via the DOI in this record. ; Data availability: GWAS summary statistics for FG/FI analyses presented in this manuscript are deposited on https://www.magicinvestigators.org/downloads/ and will be also be available through the NHGRI-EBI GWAS Catalog https://www.ebi.ac.uk/gwas/downloads/summary-statistics. Raw files for RNA-seq mRNA expression in islet donors have been deposited in NCBI GEO database with the accession code GSE50398. Summary-level GWAS results for genetic correlation analysis with glycemic traits were downloaded from the LDHub database (http://ldsc.broadinstitute.org/ldhub/). Islets from 89 cadaver donors were provided by the Nordic Islet Transplantation Programme (http://www.medscinet.com/nordicislets/). The dexseq_count python script for RNA sequencing analysis in human pancreatic islets was downloaded from http://www-huber.embl.de/pub/DEXSeq/analysis/scripts/. Raw files for RNA-seq mRNA expression in islet donors have been deposited in NCBI GEO database with the accession code GSE50398. ; Differences between sexes contribute to variation in the levels of fasting glucose and insulin. Epidemiological studies established a higher prevalence of impaired fasting glucose in men and impaired glucose tolerance in women, however, the genetic component underlying this phenomenon is not established. We assess sex-dimorphic (73,089/50,404 women and 67,506/47,806 men) and sex-combined (151,188/105,056 individuals) fasting glucose/fasting insulin genetic effects via genome-wide association study meta-analyses in individuals of European descent without diabetes. Here we report sex dimorphism in allelic effects on fasting insulin at IRS1 and ZNF12 loci, the latter showing higher RNA expression in whole blood in women compared to men. We also observe sex-homogeneous effects on fasting glucose at seven novel loci. Fasting insulin in women shows stronger genetic correlations than in men with waist-to-hip ratio and anorexia nervosa. Furthermore, waist-to-hip ratio is causally related to insulin resistance in women, but not in men. These results position dissection of metabolic and glycemic health sex dimorphism as a steppingstone for understanding differences in genetic effects between women and men in related phenotypes. ; Academy of Finland ; ADA ; Biotechnology and Biological Sciences Research Council (BBSRC) ; BHF ; Clinical Translational Science Institute ; Croatian Ministry of Science ; Directorate C - Public Health and Risk Assessment, Health & Consumer Protection ; Dutch Kidney Foundation ; Estonian Research Council ; European Research Council (ERC) ; European Regional Development Fund (ERDF) ; European Union Horizon 2020 ; Federal Ministry of Education and Research (BMBF), Germany ; Finnish Funding Agency for Technology and Innovation ; German Research Foundation ; Greek General Secretary of Research and Technology ; Icelandic National Bioethics Committee ; IFB Adiposity Diseases ; IngaBritt och Arne Lundberg's Research Foundation ; Italian Ministry of Health ; Knut & Alice Wallenberg foundation ; Kuopio University Hospital from Ministry of Health and Social Affairs ; Affymetrix, Inc ; Lundberg Foundation ; Medical Research Council (MRC) ; Mid-Atlantic Nutrition Obesity Research Center ; Ministry of Education and Culture of Finland ; MRC-GSK pilot programme ; NHLBI ; NIA ; NIH ; Nordic Centre of Excellence on Systems biology in controlled dietary interventions and cohort studies, SYSDIET ; Novo Nordisk Foundation ; NWO/ZonMW ; Spinozapremie ; Rutgers University Cell and DNA Repository ; Stockholm County Council ; Swedish Foundation for Strategic Research ; Swedish Heart-Lung Foundation ; Swedish Research Council ; Swiss National Science Foundation ; TEKES ; Torsten och Ragnar Söderbergs Stiftelser ; Wellcome Trust ; Yrjö Jahnsson Foundation ; Note that the full list of funders and grant numbers is available in the online article and in the PDF in this record