Disparate effects of pharmacotherapy on plasma plasminogen activator inhibitor-1 levels in women with the polycystic ovary syndrome

Abstract

Objective: Polycystic ovary syndrome (PCOS) is characterized by obesity and insulin resistance (IR), which result in elevated plasminogen activator inhibitor-1 (PAI-1) levels. We aimed to assess the changes in PAI-1 levels in PCOS during treatment with metformin and during weight loss.

Design: Twenty-three normal weight women with PCOS were given metformin 850 mg bid for 6 months. Fifty overweight/obese women with PCOS were prescribed an energy-restricted diet, were instructed to exercise and were randomized to orlistat 120 mg tid or sibutramine 10 mg qd for 6 months.

Results: In normal weight women, treatment with metformin reduced the body mass index (BMI) and circulating androgens, improved markers of IR and lowered PAI-1 levels. In overweight/obese women, sibutramine and orlistat yielded comparable reductions in BMI and markers of IR. In contrast, the effects on the free androgen index (FAI) differed (p=0.027): sibutramine reduced the FAI (p=0.005), whereas orlistat had no effect. The effects of sibutramine and orlistat on PAI-1 levels also differed (p=0.042): sibutramine reduced PAI-1 levels (p<0.001), whereas orlistat had no effect.

Conclusions: Metformin and sibutramine, but not orlistat, reduce PAI-1 levels in PCOS. The reduction in circulating androgens during metformin and sibutramine treatment might be implicated in this decline.