Endocrine Abstracts

Background: PCOS is associated with a clustering of cardiovascular risk factors. Increased serum levels of vascular endothelial growth factor (VEGF) are thought to be proatherogenic, and have also been found to be elevated in PCOS. This study was undertaken to determine the changes of VEGF in patients with PCOS after rimonabant and/or metformin intervention.

Methods: A 6-month randomised open labelled parallel study of rimonabant or metformin in 20 patients with PCOS with a body mass index ≥30 kg/m². Subsequently, patients who were on 3 months of rimonabant were changed over to metformin for 3 months, whereas those on 3 months of metformin were continued on metformin for another 3 months.

Results: After 3 months of rimonabant (V1/2) there was a significant increase in VEGF (99.24+17.61 vs 116.16+15.82 pg/ml, P< 0.01) whilst there was no significant change in VEGF in the metformin group (110.29+25.17 vs 111.47+24.84 pg/ml, P=0.75). However there was a significant decrease in VEGF in the metformin group between month 3 and month 6 (V2/3) (111.47+24.84 vs 91.21+16.44 pg/ml, P=0.04). There was also no significant change in VEGF during metformin treatment in the rimonabant group (V2/V3) (116.16+15.82 vs 106.45+36.43 pg/ml, P=0.18).

Weight change in the rimonabant group was V1/V2 104.6+4.6 vs 98.4+4.7 kg, P<0.01; V2/V3 98.4+4.7 vs 98.6+4.8 kg; P=0.96; in the metformin group V1/V2 103.8+3.9 vs 102.2+4.1 kg, P=0.08; V2/V3 102.2+4.1 vs 100.9+4.2 kg, P=0.02. There was no correlation between changes in weight and VEGF levels.

Conclusion: Metformin decreased VEGF levels after 6 months independent of weight change, however rimonabant increased VEGF levels despite significant weight loss suggesting a proatherogenic pharmacological effect.