Exp Clin Endocrinol Diabetes 2006; 114 - OR3_15
DOI: 10.1055/s-2006-932853

Benefit of metformin therapy in women with polycystic ovary syndrome is independent of insulin resistance

S Tan 1, S Hahn 1, S Rösler 2, S Benson 3, R Kimmig 2, K Mann 1, OE Janssen 1
  • 1University Hospital of Essen Medical School, Division of Endocrinology, Department of Medicine, Essen, Germany
  • 2University Hospital of Essen Medical School, Department of Obstetrics and Gynecology, Essen, Germany
  • 3University Hospital of Essen Medical School, Institute for Medical Psychology, Essen, Germany

Introduction: Polycystic Ovary Syndrome (PCOS) is characterised by chronic anovulation paired with infertility and hyperandrogenism. PCOS affects 5–10% of reproductive age women. 50% of PCOS patients are obese. Insulin sensitising agents have been shown to improve both reproductive and metabolic aspects of PCOS. Not all of PCOS affected women are insulin resistant and it is not clear whether insulin resistance is part of the pathogenesis of PCOS.

Objective: To determine whether pre-treatment insulin resistance modulates the improvement of clinical and biochemical markers of metformin treatment of PCOS patients.

Methods: 188 PCOS patients (mean age 28.8±6.4 years) were divided into three groups according to BMI (I: BMI<25kg/m2, II: BMI 25–29kg/m2, III: BMI >30kg/m2) and were treated with metformin in a weight adapted dose for six months. At baseline and after six months of metformin therapy, a personal interview, physical examination and blood testing were performed. Markers of insulin resistance were assessed by a 3h oral glucose tolerance test. The three groups did not differ significantly in age or the presence of clinical or biochemical signs of PCOS except for BMI and the degree of insulin resistance.

Main Outcome Measures: ovulation rate, presence of acne, alopecia, hirsutism and polycystic ovaries (PCO)

Results: In all three groups testosterone levels decreased significantly (I: 2.6±0.9vs. 1.8±0.7, p<0.0001, II: 2.5±0.9 vs. 1.9±0.6, p=0.0005, III: 2.7±0.9 vs. 2.1±0.8, p<0.0001). Improvement of menstrual disturbance (I: 97.7 vs. 40.5%, p<0.0001, II: 92.9 vs. 53.8%, p<0.0001, III: 96.0 vs. 49.0%, p<0.0001) and acne (I: 31.8 vs. 11.6%, p=0.012, II: 53.7 vs. 22.0%,p=0.004, III: 42.2 vs. 27.8%,p=0.006) was similiar in the three groups. Independent of BMI, alopecia, hirsutism and PCO did not improve significantly.

Conclusion: Metformin improves testosterone-levels, menstrual disturbance and acne in PCOS-women independently of insulin resistance.