Serum lipoprotein responses during active and stable weight reduction in reproductive obese females.

An increase in high density lipoprotein-cholesterol (HDL-C) and a reduction in low density lipoprotein-cholesterol (LDL-C) accompany weight reduction in obese males. In contrast, obese females have had variable responses in these two lipoproteins after weight reduction. To evaluate the effects of weight reduction in obese women, 15 morbidly obese eugonadotropic women of reproductive age had serum lipids and lipoproteins measured before and after achieving a stable and reduced weight by either diet and/or a gastric stapling procedure. Total testosterone (T), free testosterone (free T), and testosterone-binding globulin serum concentrations were also determined before and after achieving a stable reduced weight to assess the role of androgens in modulating any lipoprotein changes. In 10 subjects, lipid analysis was also performed during active weight loss. Total serum triglycerides fell from 106 +/- 53 to 76 +/- 30 mg/dl during active weight loss (P less than 0.025). Total cholesterol, LDL-C, HDL-C, and the LDL-C to HDL-C ratio did not change. In contrast, after achieving a stable reduced weight (mean weight reduction, 25.9 +/- 6.7 kg), HDL-C rose from 24 +/- 8 to 32 +/- 9 mg/dl (P less than 0.005). This was accompanied by a reduction in LDL-C from 145 +/- 23 to 135 +/- 30 mg/dl (P less than 0.01) and in the LDL-C to HDL-C ratio from 6.7 +/- 2.6 to 4.8 +/- 1.9 (P less than 0.001). Total triglycerides and total cholesterol were unchanged. After obtaining a stable reduced weight, testosterone-binding globulin increased and free T fell, but no significant correlation existed between the changes in androgens and the changes in lipoprotein responses. Thus, in morbidly obese women, weight reduction increases HDL-C and lowers LDL-C serum concentrations. The reduction in the LDL-C to HDL-C ratio suggests that weight loss may favorably reduce the risk of coronary artery disease in these patients. A concurrent reduction of free T with weight loss does not appear to be a major controlling influence in these lipoprotein alterations.