Aims/hypothesis  

Intra-abdominal fat (IAF) is an important risk factor for CHD and type 2 diabetes, and in cross-sectional studies is associated with the metabolic syndrome (MetS). Our aim was to determine whether IAF accumulation predicts the future development of MetS in non-diabetic Japanese-Americans.

Subjects and methods  

We conducted a prospective study of 457 Japanese-American men and women (mean±SD: age 51.5 ± 12.0 years, BMI 23.9 ± 3.1 kg/m²) without diabetes or MetS at baseline. Of these, 408 completed a 5-year follow-up and 366 completed a 10-year follow-up. BMI, waist circumference, IAF and subcutaneous fat (SCF) areas by computed tomography, blood pressure, fasting plasma glucose, insulin, triacylglycerol and HDL-cholesterol were measured at baseline and at 5- and 10-year follow-up. MetS was defined using National Cholesterol Education Program Adult Treatment Panel III criteria.

Results  

Incidence of MetS was 15.3% at 5 years and 17.8% at 10 years. A change of 1 SD in IAF area was associated with a 2.1-fold increase in the odds of MetS at 10 years (odds ratio = 2.08, 95% CI 1.41–3.07) after adjusting for age, sex, baseline IAF and the presence of each individual MetS criteria at baseline. This association was independent of changes in fasting insulin and SCF areas.

Conclusions/interpretation  

We conclude that IAF accumulation over time independently predicts the development of MetS and thus may play an important role in the development of MetS in Japanese-Americans.