Endocrine Abstracts

Background: Women with polycystic ovarian syndrome (PCOS) tend to have a cluster of several coronary risk factors, including atherogenic dyslipidaemia. Metformin has been used to improve their hyperandrogenism and to induce ovulation. However, its effects on hyperlipidaemia are less clear and it is not known if metformin also ameliorates lipid intrinsic variability.

Aim: The primary end point of the study was to evaluate the effects of metformin and a hypocaloric diet on mean serum lipids levels and their biological variation in obese PCOS patients. Secondary end points included changes in body mass index (BMI), waist-hip ratio, percentage of body fat, HOMA-IR and blood pressure.

Methods: This was an open labelled study. Eleven obese patients (BMI 33.7±6 kg/m² (mean±S.D.)) were recruited. The biological variation was assessed by measuring total cholesterol, LDL, HDL and tryglicerides at 4-day intervals on 10 consecutive occasions before and after 3 months treatment with metformin and midly hypocaloric diet (1500 kcal/day).

The study was approved by our local ethics committee. The clinical trial registration number is ISRCTN65353256.

Results: Treatment with metformin and a hypocaloric diet improved mean LDL levels (3±0.8 vs 3.20±0.8, P=0.03) and its intrinsic biological variation (CV_i=10.6 vs 12%). Significant improvements in BMI, waist-hip ratio and blood pressure were also observed. No significant changes on mean HOMA-IR, total cholesterol, HDL and tryglicerides or their biological variation were noticeable.

Conclusion: The addition of metformin to a mildly hypocaloric diet improved the cardiometabolic risk factor profile and biological variation of LDL in obese PCOS patients.