Influence of adiposity on leptin, LH and androgen levels in lean, overweight and obese PCOS patients.

BACKGROUND: Leptin modulates hypothalamic-pituitary-gohadal axis functions.
OBJECTIVE: To assess the influence of leptin on LH, and to investigate the potential association of leptin with body mass index (BMI) and androgen concentrations in women with polycystic ovary syndrome (PCOS).
DESIGN: Levels of leptin, LH, FSH, E2, testosterone, and androstenedione were measured. PATIENTS: 91 patients with PCOS were included in this study.
METHODS: Patients were stratified into three groups according to BMI: normal weight (NW group, N=31), overweight patients (OW group N=30) and obese PCOS patients (Ob group, N=30). Results-Hyperandrogenemia was present in the studied group. A significant correlation was observed between BMI and androgens (both P < 0.01), and between leptin levels and androgens (respectfully for androstenendione P < 0.01 and for testosterone P < 0.05). A positive correlation between the LH and leptin levels in NW (P < 0.05) and OW (P < 0.001) patients was noticed, while negative correlation is seen in the Ob group (P < 0.01). In OW patients the significant positive correlation between leptin levels and androstenendione was found (P < 0.001), after correction for BMI. A linear regression model indicated that leptin concentrations and BMI contributed negatively and significantly (P < 0.001) to LH concentrations.
CONCLUSION: LH secretion in PCOS patients can be viewed as a consequence of the activity of different adipocyte and neuroendocrine factors. The attenuation in basal LH levels in obese PCOS women might be related to a leptin-resistant state.