Impact of total and central obesity on vascular mortality in patients undergoing coronary angiography

OBJECTIVE: To prospectively investigate the impact of total and central obesity on vascular mortality in patients undergoing coronary angiography. DESIGN: Prospective cohort study; mean follow-up 2.2 y. SUBJECTS: Men (n = 513) and women (n = 243) undergoing coronary angiography for the evaluation of coronary artery disease. MEASUREMENTS: Body mass index (BMI) was used as a measure of total obesity; waist-to-hip ratio (WHR) and waist circumference (WCf) as measures of central obesity. The primary study end point was vascular mortality; secondary study end points were total mortality, major coronary events, and cumulative vascular events. RESULTS: For both genders, BMI, WHR, and WCf correlated significantly with fasting plasma glucose, with HOMA insulin resistance, with triglycerides, and inversely with HDL cholesterol (P < 0.001 for all correlations). In Cox regression analysis adjusting for age, gender, smoking, and total cholesterol, BMI was not associated with any study end point. In contrast, WHR (standardized adjusted odds ratios (OR) 2.01, 95% CI 1.02-3.93 for men and 2.63, 95% CI 1.38-5.00 for women), and WCf (OR = 2.31, 95% CI 1.16-4.60 for men and 8.71, 95% CI 1.78-42.68 for women) proved independently predictive of vascular mortality. Additional adjustment for diabetes and hypertension did not substantially alter these results. Also, the predictive value of WHR and Wcf was retained after adjustment for drug treatment and the presence of significant coronary artery disease at baseline. Further, WHR and WCf were associated with total mortality, major coronary events, and cumulative vascular end points. CONCLUSION: Both total and central obesity are associated with insulin resistance and with an atherogenic lipoprotein profile. However, only central obesity is significantly and independently predictive of the 2-y vascular mortality in coronary patients.