Clinical, endocrine and metabolic effects of metformin vs N-acetyl-cysteine in women with polycystic ovary syndrome.

OBJECTIVE: To evaluate the clinical, endocrine and metabolic effects of metformin and N-acetyl-cysteine (NAC) in patients with polycystic ovary syndrome (PCOS).

STUDY DESIGN: In this prospective trial, 100 women with PCOS were randomly divided to receive metformin (500 mg p.o. three times daily) or NAC (600 mg p.o. three times daily) for 24 weeks. Hyperandrogenism, lipid profiles, hirsutism scores, menstrual irregularity, insulin sensitivity and tumour necrosis factor-α (TNF-α) levels were measured at baseline and after the treatment period.

RESULTS: Both treatments resulted in a significant decrease in body mass index, hirsutism score, fasting insulin, HOMA index, free testosterone and menstrual irregularity compared with baseline values, and both treatments had equal efficacy. NAC led to a significant decrease in both total cholesterol and low-density lipoprotein levels, whereas metformin only led to a decrease in total cholesterol level. Although TNF-α levels increased following treatment for both groups, the difference from baseline was not significant.

CONCLUSIONS: Metformin and NAC appear to have comparable effects on hyperandrogenism, hyperinsulinaemia and menstrual irregularity in women with PCOS. The effects of metformin and NAC on insulin sensitivity are not associated with TNF-α.