Cardiovascular disease risk of abdominal obesity vs. metabolic abnormalities

It remains unclear whether abdominal obesity increases cardiovascular disease (CVD) risk independent of the metabolic abnormalities that often accompany it. Therefore, the objective of this study was to evaluate the independent effects of abdominal obesity vs. metabolic syndrome and diabetes on the risk for incident coronary heart disease (CHD) and stroke. The Framingham Offspring, Atherosclerosis Risk in Communities, and Cardiovascular Health studies were pooled to assess the independent effects of abdominal obesity (waist circumference 102cm for men and 88cm for women) vs. metabolic syndrome (excluding the waist circumference criterion) and diabetes on risk for incident CHD and stroke in 20,298 men and women aged 45 years. The average follow-up was 8.3 (s.d. 1.9) years. There were 1,766 CVD events. After adjustment for demographic factors, smoking, alcohol intake, number of metabolic syndrome components, and diabetes, abdominal obesity was not significantly associated with an increased risk of CVD (hazard ratio (HR) (95% confidence interval): 1.09 (0.98, 1.20)). However, after adjustment for demographics, smoking, alcohol intake, and abdominal obesity, having 1-2 metabolic syndrome components, the metabolic syndrome and diabetes were each associated with a significantly increased risk of CVD (2.12 (1.80, 2.50), 2.82 (1.92, 4.12), and 5.33 (3.37, 8.41), respectively). Although abdominal obesity is an important clinical tool for identification of individuals likely to possess metabolic abnormalities, these data suggest that the metabolic syndrome and diabetes are considerably more important prognostic indicators of CVD risk.