Endocrine Abstracts

OBJECTIVE: To evaluate and compare the effect of treatment with orlistat versus metformin on the hormonal and biochemical features of patients with polycystic ovarian syndrome (PCOS)

METHODS: 21 Caucasian women with PCOS (mean plus/minus SEM, age 27 plus/minus 0.9 years, and body mass index 36.7 plus/minus 3.3) participated in this prospective, randomised, open labelled, study. All subjects had an eight week run in period of dietary modification and then randomised to receive either metformin (500 mg TDS) or Orlistat (120 mg TDS) for 3 months. Weight, blood pressure and fasting blood samples were taken at screening, randomization and on completion. Insulin resistance was calculated using the Homeostasis Model Assessment method (HOMA-IR = (Insulin x glucose)/22.5).

RESULTS: The results are expressed as mean plus/minus SEM. When compared to baseline, treatment with both orlistat (3.24 plus/minus 0.4 vs 3.97 plus/minus 0.4 mmol/L, p=0.039) and metformin (3.37 plus/minus 0.4 vs 4.16 plus/minus 0.3 mmol/L, p=0.048) produced a significant reduction in total testosterone. Treatment with orlistat produced a 4.69% reduction in weight which was significantly less than at baseline (99.0 plus/minus 6.0 vs 94.6 plus/minus 6.1 Kg, p=0.002) and to the change produced by metformin (4.69% vs 1.02%, p=0.006). Orlistat treatment produced a 12.5% reduction in fasting insulin and a 10.8% reduction in HOMA-IR while treatment with metformin produced a 7.39% reduction in fasting insulin and 7.19% reduction in HOMA-IR compared to baseline. Between group comparison showed similar but non-significant reduction of fasting insulin (p=0.426) and HOMA-IR (p=0.756). No significant difference in SHBG concentration or lipid parameters was seen for either group.

CONCLUSIONS: In this study orlistat produced a significant reduction in weight and total testosterone. The reduction in total testosterone was similar to that seen following treatment with metformin. Orlistat may therefore prove to be a useful adjunct in the treatment of PCOS.