Body composition is improved during 12 months' treatment with metformin alone or combined with oral contraceptives compared with treatment with oral contraceptives in polycystic ovary syndrome

Abstract

Context: Central obesity in polycystic ovary syndrome (PCOS) is associated with increased inflammatory markers and increased risk for type 2 diabetes.

Objective: The objective of the study was to evaluate whether treatment with metformin (M) or M combined with oral contraceptive pills (OCPs) resulted in a more advantageous body composition than treatment with OCP alone.

Setting: The study was conducted at an outpatient clinic.

Patients and interventions: This was a randomized, controlled clinical trial. Ninety patients with PCOS were randomized to 12 months' treatment with M (2 g/d), M + OCP (150 mg desogestrel+30 μg ethinylestradiol), or OCP. Whole-body dual-energy x-ray absorptiometry scans and clinical and hormonal evaluations were performed before and after the intervention period. A total of 65 of 90 patients completed the study.

Main outcome measures: Changes in weight at 6 and 12 months and changes in regional fat mass estimates at 12 months were measured.

Results: Dropout rates between intervention groups were not significantly different. Treatment with M and M+OCP were superior to OCP regarding weight and regional fat mass. The median (quartiles) weight changes during 12 months of M, M+OCP, and OCP treatment were -3.0 (-10.3; 0.6), -1.9 (-4.9; 0.1), and 1.2 (-0.8; 3.0) kg, respectively, P < .05. Upper to lower fat mass ratio was unchanged. Changes in body composition were predicted by the type of medical intervention (M, M+OCP, or OCP) and not by body mass index at study inclusion. OCP and M+OCP were superior to M regarding reduction in free T levels.

Conclusions: M treatment alone or in combination with OCP was associated with weight loss and improved body composition compared with OCP, whereas free T levels decreased during M+OCP or OCP. Combined treatment with M+OCP should be considered as an alternative to treatment with OCP alone to avoid weight gain in PCOS.

Trial registration: ClinicalTrials.gov NCT00451568.