Objective: Although body mass index (BMI) is commonly used to assess risk for cardiovascular disease (CVD), there is an obvious need for prospective studies of different ethnics to evaluate the predicting power of various obesity variables for CVD outcomes.
Methods: The study population consisted of 1931 men aged ≥40 years free of CVD at baseline. After a median follow up of 7.6 years, 254 CVD events occurred. Demographic data were collected at baseline; blood pressure and anthropometric variables such as BMI, waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) were measured according to a standard protocol. CVD outcome was defined as any coronary heart disease events, stroke, or CVD death. Cox proportional hazards regression was used to calculate hazard ratio (HR) of CVD for each anthropometric variables in two model; age adjusted model and full model adjusted for age, hypertension, smoking, family history of premature CAD. Receiver operator characteristic (ROC) curves were constructed to assess sensitivity and specificity of the variables in prediction of risk.
Results: In the age adjusted model all measures of obesity predict CVD in a high level of significance. According to Cox proportional hazard modeling, after controlling confounding factors, HRs and 95% CI (for 1 S.D. increase) for CVD were 1.17 (1.011.03) with BMI, 1.24 (1.061.37) with WC, 1.19 (1.051.35) with WHR and WHtR. Area under ROC curve (95% CI) were 0.56 (0.50.6) for BMI, 0.59 (0.550.62) for WC, 0.59 (0.560.64) for WHR and WHtR.
Conclusions: Waist-related variables are superior clinical measures of obesity for predicting CVD outcomes in Iranian adult men. WHR or WHtR are not more useful than WC alone.
Keywords: Obesity, Cardiovascular disease, follow-up.