[Female obesity: testosteronemia is positively correlated with peripheral insulin resistance]

Hyperinsulinemia and hyperandrogenemia are frequent in obese women. The aim of this study is to examine the relationship between the degree of insulin resistance and plasma androgens, and the role of android obesity. We studied 16 obese (BMI = 39.3 +/- 1.6 kg/m2) premenopausal non diabetic women (age = 28.2 +/- 1.4 years). The peripheral insulin sensitivity was determined during an euglycemic insulin clamp study. Serum total testosterone (TT), free testosterone (FT), androstenedione (A) were measured in each women. We compared these results to those of 5 control subjects (BMI = 20 +/- 1 kg/m2). Insulin resistance was more severe in the obese women than in the control subjects: Vmax = 9.1 +/- 0.5 mg/kg/mm vs 19.1 +/- 1.0 mg/kg/mn (p < 0.01) and Km = 152.2 +/- 13.9 microU/ml vs 42.6 +/- 5.8 microU/ml (p < 0.01). Significant positive correlations were demonstrated in the obese women between Km and both total testosterone (r = 0.74; p < 0.01) and free testosterone (r = 0.52; p < 0.05). There was no correlation between Km and Androstenedione. The waist to hip ratio (WHR) differentiated two groups of age--and weight-matched obese women; Gr 1:10 upper body obese women (WHR = 0.90 +/- 0.10; BMI = 39.0 +/- 1.9 kg/m2); Gr 2: 6 lower body obese (WHR = 0.77 +/- 0.02; BMI = 40.0 +/- 3.1 kg/m2. Insulin resistance was more severe in the Gr I: Km = 174 +/- 17 microU/ml, than in the Gr 2: Km = 101 +/- 8 microU/ml (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)