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Aims Genetic disposition and lifestyle factors are understood as independent components underlying the risk of multiple diseases. In this study, we aim to investigate the interplay between genetics, educational attainment—an important denominator of lifestyle—and coronary artery disease (CAD) risk. Methods and results Based on the effect sizes of 74 genetic variants associated with educational attainment, we calculated a ‘genetic education score’ in 13 080 cases and 14 471 controls and observed an inverse correlation between the score and risk of CAD [P = 1.52 × 10−8; odds ratio (OR) 0.79, 95% confidence interval (CI) 0.73–0.85 for the higher compared with the lowest score quintile]. We replicated in 146 514 individuals from UK Biobank (P = 1.85 × 10−6) and also found strong associations between the ‘genetic education score’ with ‘modifiable’ risk factors including smoking (P = 5.36 × 10−23), body mass index (BMI) (P = 1.66 × 10−30), and hypertension (P = 3.86 × 10−8). Interestingly, these associations were only modestly attenuated by adjustment for years spent in school. In contrast, a model adjusting for BMI and smoking abolished the association signal between the ‘genetic education score’ and CAD risk suggesting an intermediary role of these two risk factors. Mendelian randomization analyses performed with summary statistics from large genome-wide meta-analyses and sensitivity analysis using 1271 variants affecting educational attainment (OR 0.68 for the higher compared with the lowest score quintile; 95% CI 0.63–0.74; P = 3.99 × 10−21) further strengthened these findings. Conclusion Genetic variants known to affect educational attainment may have implications for a health-conscious lifestyle later in life and subsequently affect the risk of CAD.

AIMS: Because low-grade inflammation may play a role in the pathogenesis of coronary heart disease (CHD), and pro-inflammatory cytokines govern inflammatory cascades, this study aimed to assess the associations of several pro-inflammatory cytokines and CHD risk in a new prospective study, including meta-analysis of prospective studies. METHODS AND RESULTS: Interleukin-6 (IL-6), IL-18, matrix metalloproteinase-9 (MMP-9), soluble CD40 ligand (sCD40L), and tumour necrosis factor-α (TNF-α) were measured at baseline in a case-cohort study of 1514 participants and 833 incident CHD events within population-based prospective cohorts at the Danish Research Centre for Prevention and Health. Age- and sex-adjusted hazard ratios (HRs) for CHD per 1-SD higher log-transformed baseline levels were: 1.37 (95% CI: 1.21-1.54) for IL-6, 1.26 (1.11-1.44) for IL-18, 1.30 (1.16-1.46) for MMP-9, 1.01 (0.89-1.15) for sCD40L, and 1.13 (1.01-1.27) for TNF-α. Multivariable adjustment for conventional vascular risk factors attenuated the HRs to: 1.26 (1.08-1.46) for IL-6, 1.12 (0.95-1.31) for IL-18, 1.21 (1.05-1.39) for MMP-9, 0.93 (0.78-1.11) for sCD40L, and 1.14 (1.00-1.31) for TNF-α. In meta-analysis of up to 29 population-based prospective studies, adjusted relative risks for non-fatal MI or CHD death per 1-SD higher levels were: 1.25 (1.19-1.32) for IL-6; 1.13 (1.05-1.20) for IL-18; 1.07 (0.97-1.19) for MMP-9; 1.07 (0.95-1.21) for sCD40L; and 1.17 (1.09-1.25) for TNF-α. CONCLUSIONS: Several different pro-inflammatory cytokines are each associated with CHD risk independent of conventional risk factors and in an approximately log-linear manner. The findings lend support to the inflammation hypothesis in vascular disease, but further studies are needed to assess causality.

Aims It is uncertain whether there are associations between circulating levels of insulin markers and coronary heart disease (CHD) risk. We report an updated meta-analysis of studies of circulating levels of three insulin markers (fasting insulin, non-fasting insulin, and pro-insulin) and CHD risk. Methods and results Prospective studies based in Western populations that reported on associations between levels of fasting insulin, non-fasting insulin, and pro-insulin and incident CHD [defined as non-fatal myocardial infarction (MI) or coronary death] were identified by computer-based searches and by manual searches of the relevant literature. Nineteen relevant population-based studies were identified, of which 14 reported on fasting insulin levels involving 2649 CHD cases, eight reported on non-fasting insulin levels involving 1980 CHD cases and three reported on pro-insulin levels involving 413 CHD cases. In a comparison of individuals who had circulating levels of each of these markers in the top third with those in the bottom third of the population, the odds ratio for CHD was 1.12 [95% confidence interval (CI): 0.98–1.28] for raised fasting insulin, 1.35 (1.14–1.60) for raised non-fasting insulin, and 2.23 (1.65–3.00) for raised pro-insulin. There was no good evidence of heterogeneity in these estimates attributable to the several study characteristics recorded, including sex, assay methods used, or degree of adjustment of risk estimates, but the available data in many of these subgroups, particularly by sex, are sparse. Conclusion Associations between CHD risk and fasting or non-fasting insulin levels are likely to be more modest than previously suspected. Preliminary data suggest that pro-insulin levels may be more strongly associated with CHD risk than are insulin levels, and this possibility should be evaluated in larger and more rigorous studies.

Aims To determine whether circulating von Willebrand factor concentrations are prospectively related to risk of coronary heart disease in the general population. Methods and Results We measured baseline von Willebrand factor values in the stored serum samples of 625 men with major coronary events and in 1266 controls ‘nested’ in a prospective study of 5661 men aged 40–59 years, recruited from general practices in 18 British towns in 1978–1980 and followed up for 16 years for fatal coronary heart disease and non-fatal myocardial infarction. We conducted a meta-analysis of previous relevant studies to place our results in context. Men in the top third of baseline von Willebrand factor values (tertile cutoff >126 IU . dl 1 ) had an odds ratio for coronary heart disease of 1·83 (95% confidence interval 1·43–2·35; 2P

AIMS: To examine associations between Chlamydia pneumoniae IgA titres and incident coronary heart disease, and to compare them with associations previously reported between C. pneumoniae IgG titres and coronary heart disease. METHODS AND RESULTS: We measured serum concentrations of C. pneumoniae IgA antibodies in 502 coronary heart disease cases and in 1005 age- and town-matched controls 'nested' in a community-based prospective study of 5661 British men (mean follow-up in controls, 16 years), and conducted a meta-analysis of published prospective studies to place our findings in context. Two hundred and twenty-one (44%) of the cases were in the top third of C. pneumoniae IgA titres compared with 336 (33%) of the controls, yielding an odds ratio for coronary heart disease of 1.84 (95% confidence interval 1.40-2.43) which was largely unchanged after adjustment. In aggregate, the present study and nine previously reported prospective studies of C. pneumoniae IgA titres involved 2283 cases, yielding a combined odds ratio for coronary heart disease of 1.25 (1.03-1.53), with no significant heterogeneity among the ten studies (chi(2)9=7.8; P>0.1). This combined odds ratio is compatible with that previously reported for C. pneumoniae IgG titres and coronary heart disease (1.15, 0.97-1.36). CONCLUSION: Neither C. pneumoniae IgA titres nor IgG titres are strongly predictive of coronary heart disease in the general population.