Objective: To assess whether the extent of abdominal fat distribution, as measured by the waist to hip ratio (WHR), might account for the sex differences in the levels of cardiovascular risk factors.
Design: Cross-sectional age-matched study.
Subjects: 1264 men and 1264 premenopausal women, aged 30-49 y, free from known cardiovascular diseases and diabetes, included in the prospective study, D.E.S.I.R.
Measurements: (1) body mass index (BMI), WHR and blood pressures; (2) fasting concentrations of blood glucose, insulin, lipids and lipoprotein subfractions, and apolipoproteins; and (3) smoking status, physical activity, and alcohol consumption.
Results: After taking into account age and BMI, there were gradual relationships, within and across sexes, between WHR and the levels of most lipids and lipoproteins, of fasting glucose and insulin, and, to a lesser extent, of blood pressures. In particular, men and women with similar BMI and WHR had similar levels of triglycerides. Multivariate regression analysis showed that the variance of cardiovascular risk factors explained by the model was increased when sex was included, after controlling for age, BMI and lifestyle habits (all P<0.01). If WHR was included in the model, sex had no additional effect on total cholesterol (P>0.09 for change in total r2 ) or triglycerides (P>0.40 for change in total r2). In contrast, for other cardiovascular risk factors, adjustment for covariates and WHR did not fully eliminate the sex differences, although WHR increased the variance explained with or without additional control for sex (all P<0.01).
Conclusion: The continuous increase of cardiovascular risk factors with WHR, especially for lipids and lipoproteins, suggests that the abdominal body fat distribution may partially explain the relative unhealthier cardiovascular risk profile of men.