Patterns of Abdominal Fat Distribution: The Framingham Heart Study

Abstract

Background The prevalence of abdominal obesity exceeds that of general obesity. We sought to determine the prevalence of abdominal subcutaneous and visceral obesity, and to characterize the different patterns of fat distribution in a community-based sample.

Methods Participants from the Framingham Heart Study (n=3348, 48% women, mean age 52 years) underwent multi-detector computed tomography; SAT and VAT volumes were assessed. Sex-specific high SAT and VAT definitions were based on 90^th percentile cut-points from a healthy-referent sample. Metabolic risk factors were examined in sub-groups of elevated SAT and VAT.

Results The prevalence of high SAT was 30% (women) and 31% (men), and high VAT was 44% (women) and 42% (men). Overall, 27.8% of the sample was discordant for high SAT and high VAT: 19.9% had SAT below but VAT ≥ the 90^th percentile, and 7.9% had SAT above but VAT < the 90^th percentile. The prevalence of metabolic syndrome was higher among women and men with SAT < the 90^th percentile and high VAT than in those with high SAT but VAT < the 90^th percentile, despite lower BMI and WC. Findings were similar for hypertension, elevated triglycerides, and low HDL cholesterol.

Conclusions Nearly one-third of our sample has abdominal subcutaneous obesity, and over 40% have visceral obesity. Clinical measures of BMI and waist circumference may misclassify individuals in terms of VAT and metabolic risk.