Objective: The objectives were to study the relationships of insulin resistance with generalized and abdominal obesity, and body fat patterning in urban postpubertal Asian Indian children.
Design: Cross-sectional, population-based epidemiological study.
Subjects: In all, 250 (155 males and 95 females) healthy urban postpubertal children.
Measurements: Anthropometric profile, percentage of body fat (%BF), fasting serum insulin, and lipoprotein profile.
Results: Fasting insulin correlated significantly with body mass index (BMI), %BF, waist circumference (WC), central and peripheral skinfold thicknesses and sum of four skinfold thicknesses (Sigma 4SF) in both sexes, and with systolic blood pressure and waist-to hip circumference ratio (W-HR) in males only. Consistent increase in fasting insulin was noted with increasing values of central skinfold thickness at each tertile of peripheral skinfold thickness, WC, and %BF. Central skinfold thickness correlated with fasting insulin even after adjusting for WC, W-HR, and %BF. The odds ratios (OR) (95% CI) of hyperinsulinemia (fasting insulin concentrations in the highest quartile) were 4.7 (2.4-9.4) in overweight subjects, 8 (4.1-15.5) with high %BF, 6.4 (3.2-12.9) with high WC, 3.7 (1.9-7.3) with high W-HR, 6.8 (3.3-13.9) with high triceps skinfold thickness, 8 (4.1-15.7) with high subscapular skinfold thickness, and 10.1 (5-20.5) with high Sigma 4SF. In step-wise multiple logistic regression analysis, %BF [OR (95% CI): 3.2 (1.4-7.8)] and Sigma 4SF [OR (95% CI): 4.5 (1.8-11.3)] were independent predictors of hyperinsulinemia, similar to insulin resistance assessed by HOMA (homeostatic model of assessment) in the study.
Conclusion: A high prevalence of insulin resistance in postpubertal urban Asian Indian children was associated with excess body fat, abdominal adiposity, and excess truncal subcutaneous fat. Primary prevention strategies for coronary heart disease and diabetes mellitus in Asian Indians should focus on the abnormal body composition profile in childhood.