Adiposity, fat distribution, and cardiovascular risk

Study Objective: To determine the relative importance of adiposity and fat distribution to cardiovascular risk profile. Design: A cross-sectional study. Setting: Clinical research center funded by the National Institutes of Health. Patients: Convenience sample of 33 healthy premenopausal women with a wide range of body weight who did not have diabetes mellitus, hirsutism and virilism, gynecologic disorder, cardiac disease, or hypertension. Women participating in exercise or dietary programs or taking medication were excluded. All subjects completed the study. Interventions: Total body fat mass was determined by hydrostatic weighing, and fat distribution was assessed by subscapular skinfold thickness, subscapular-to-triceps skinfold ratio, the waist-to-hip ratio, and computed tomography. Cardiovascular risk was assessed by the serum insulin response during oral glucose stimulation; levels of triglycerides and total cholesterol; high-density lipoprotein cholesterol to total cholesterol concentrations; and systolic and diastolic blood pressures. Measurements and Main Results: The anthropometric parameters chosen were significantly associated with the cardiovascular risk profile (P < 0.001). Visceral fat distribution assessed by computed tomography accounted for a significantly greater degree of variance in the cardiovascular risk factors than the total body fat mass (P < 0.05). The cumulative insulin response was the primary metabolic variable relating the anthropometric indices to cardiovascular risk. Conclusions: Intra-abdominal fat deposition constitutes a greater cardiovascular risk than obestiy alone. Hyperinsulinemia may constitute an important component of the increased cardiovascular risk of abdominal obesity.