SERUM LEPTIN IN OBESE WOMEN WITH POLYCYSTIC-OVARY-SYNDROME IS CORRELATED WITH BODY-WEIGHT AND FAT DISTRIBUTION BUT NOT WITH ANDROGEN AND INSULIN LEVELS

Leptin is a hormone produced in the adipose tissue and its concentrati ons in peripheral blood are significantly correlated with the amount o f body fat. Whether other factors, including the pattern of body fat d istribution and several hormones (such as insulin, sex steroids, and g lucocorticoids), may be involved in the regulation of circulating bloo d leptin levels is controversial. Women with the polycystic ovary synd rome (PCOS) are hyperandrogenic and most of them are characterized by hyperinsulinemia, insulin resistance, and obesity, particularly the vi sceral phenotype. To assess the potential contribution of anthropometr ic factors, androgens, and insulin in determining leptin levels, we ex amined their relationship with body-mass index (BMI), visceral (VAT) a nd subcutaneous (SAT) adipose tissue areas, basal androgen levels, and fasting and glucose-stimulated (AUC) insulin in different groups of o bese women with PCOS (n = 23) and of age-matched obese (n = 16) and no n-obese (n = 10) otherwise healthy controls. The VAT/SAT ratio was mea sured as a parameter of body fat distribution. Serum leptin levels wer e significantly higher in obese PCOS women than in obese and normal-we ight healthy controls and, within the controls, in the obese than in t he non-obese group. In all women considered together, and in each grou p separately, leptin concentrations were highly significantly correlat ed with BMI. In addition, after adjusting for BMI, both VAT and the VA T/SAT ratio were positively and significantly correlated with leptin. Partial correlations with the VAT/SAT ratio remained significant in bo th the obese PCOS group and in controls considered separately, whereas the correlation with the SAT value was significant only in the contro l group. After adjusting for BMI, no correlation between leptin, andro gens and fasting or stimulated (like AUC) insulin was found. These fin dings indicate that leptin levels in obese women with PCOS are higher than those observed in obese and non-obese controls. Moreover, they su ggest that, other than BMI, the pattern of body fat distribution may b e an independent factor related to circulating leptin levels, which, o n the contrary, do not appear to be related to either androgen or insu lin concentrations. Copyright (C) 1998 by W.B. Saunders Company.