[The relationship between leptin, insulin-like growth factor-1 (IGF-1) and hyperinsulinemia of patients with polycystic ovarian syndrome].

Objective: To identify the effect of IGF-1 and leptin on the hyperinsulinemia (HI) of patients with polycystic ovarian syndrome (PCOS).

Methods: The case-control compared method was applied to the study. Ninety-two PCOS and 92 control subjects were involved in the study. The group of PCOS was further divided into two subgroups of 46 PCOS-HI and 46 PCOS-NHI. The leptin, IGF-1 and other hormones such as serum testosterone, DHT, DHEA, DHEA-S were measured by RIA method.

Results: Leptin and IGF-1 were higher in PCOS group (16.8 +/- 9.8 ng/mL, 214.8 +/- 131.6 ng/mL) than those in control group (11.6 +/- 6.8 ng/ mL, 118.0 +/- 82.9 ng/mL respectively, P < 0.05). Serum leptin level was higher in hyperinsulinemia group (9.2 +/- 10.2 ng/mL) than that in normal insulin group (12.5 +/- 7.6 ng/mL, P < 0.05). IGF-1 (208.7 +/- 109.7 ng/mL vs. 151.7 +/- 120.0 ng/mL, P = 0.66) and fasting glucose (5.1 +/- 0.5 mmol/L vs. 4.9 +/- 0.4 mmol/L, P = 0.15) had no significant difference between two groups. Multiple logistic regression showed that after the body mass index (BMI) adjusted, the testosterone, LH/FSH, DHT, DHEA, and DHEA-S, leptin and IGF-1 showed to be the independent risk factor for PCOS, but not to be for hyperinsulinemia in patients with PCOS.

Conclusion: The leptin and IGF-1 may contribute to the pathogenesis of PCOS, but the relationship between leptin, IGF-1 and hyperinsulinemia needs more researches to confirm.