Impact of diabetes on coronary artery disease in women and men - A meta-analysis of prospective studies

OBJECTIVE - Women are at a much lower risk of coronary disease mortality th an men are. It is widely believed that diabetes "erases" this female advant age, increasing the risk of heart disease much more in women than in men. I n reality, the extent of this increased risk is controversial, with studies showing conflicting results and wide confidence intervals. Clarification o f this issue has implications for the pathogenesis of coronary disease, and for public health efforts to reduce coronary disease in women. RESEARCH DESIGN AND METHODS - We performed a meta-analysis to calculate a s ummary estimate of the relative risk of coronary death among women with dia betes as compared to those without. For comparison, we also calculated the analogous risk among men. All prospective cohort studies containing both me n and women, and both patients with and without diabetes, were examined. Si xteen studies were identified; 10 had sufficient data for statistical analy sis. RESULTS - After combining studies that adjusted for other cardiac risk fact ors, the relative risk of coronary death from diabetes was 2.58 (95% CI 2.0 5-3.26) for women and 1.85 (1.47-2.33) for men. This difference is statisti cally significant (P = 0.045). Other sensitivity analyses did not change th ese estimates appreciably. CONCLUSIONS - The impact of diabetes on the risk of coronary death is signi ficantly greater for women than men. Further research is required to explai n this clinically meaningful difference between the sexes.