Intra-abdominal obesity and metabolic risk factors: a study of young adults

OBJECTIVE: To assess the relative importance of the extent and regional distribution of fat for metabolic risk factors in young adults. DESIGN: Cross-sectional study of findings from a hospital-based case-control study. SUBJECTS: A total of 46 adult Danish Caucasian patients (40 men and six women, aged 34-54 y). Of these, 22 had had non fatal acute myocardial infarction before 41 y of age and 24 were age- and gender-matched controls without coronary heart disease. MEASUREMENTS: Four measurements of fat: body mass index (BMI, kg/m(2)), body fat percentage measured using a dual energy X-ray absorptiometry (DEXA) scanner, waist/hip circumference ratio (WHR), and intra-abdominal adipose tissue area measured using computed tomography (CT) scanning, and eight metabolic risk factors: systolic and diastolic blood pressure, HbA(1c) percentage, fasting concentrations of capillary whole blood glucose, high-density lipoprotein (HDL) cholesterol, serum triglyceride, plasma plasminogen activator inhibitor 1 (PAI-1), and urinary albumin:creatinine excretion ratio. RESULTS: Of 46 participants, 10 were obese (BMI >30 kg/m(2)), 12 were abdominally obese (WHR >0.90 for men and >0.85 for women), and 20 were intra-abdominally obese (intra-abdominal adipose tissue area >135 cm(2)). Men had a higher intra-abdominal adipose tissue area than women (P=0.0053, Mann-Whitney U-test). In multiple regression analyses of the four fat variables, only intra-abdominal adipose tissue area significantly predicted the levels of six metabolic risk factors: systolic blood pressure, diastolic blood pressure, fasting concentrations of capillary whole blood glucose, serum HDL cholesterol, serum triglyceride, and PAI-1. The intra-abdominal adipose tissue area had a linear relation with the six metabolic risk factors. CONCLUSIONS: For young individuals, intra-abdominal fat is the important component of the body fat for six of the eight metabolic risk factors. Intra-abdominal fat might contribute to that most patients with acute myocardial infarction at a young age are men.