A comparison between rimonabant and metformin in reducing biochemical hyperandrogenaemia and insulin resistance in patients with polycystic ovary syndrome (PCOS): a randomized open-label parallel study.
BACKGROUND
Weight loss and metformin therapy are reported to be beneficial in improving the biochemical hyperandrogenaemia and insulin resistance of polycystic ovary syndrome (PCOS). Rimonabant has been found to reduce weight and improve the metabolic profile in patients with obesity, type 2 diabetes and metabolic syndrome.


OBJECTIVE
To compare the effects of insulin sensitization with metformin to weight reduction by rimonabant on biochemical hyperandrogenaemia and insulin resistance in patients with PCOS.


METHODS
A randomized, open-label parallel study.


METHODS
Endocrinology outpatient clinic in a referral centre.


METHODS
Twenty patients with PCOS and biochemical hyperandrogenaemia with a body mass index (BMI) >or= 30 kg/m(2) were recruited.


METHODS
Patients were randomized to 1.5 g daily of metformin or 20 mg daily of rimonabant.


METHODS
The primary end-point of the study was a change in total testosterone.


RESULTS
After 12 weeks of rimonabant there was a significant reduction (mean +/- SEM) in weight (104.6 +/- 4.6 vs. 98.4 +/- 4.7 kg, P < 0.01), waist circumference (116.0 +/- 3.3 vs. 109.2 +/- 3.7 cm, P < 0.01), hip circumference (128.5 +/- 4.0 vs. 124.1 +/- 4.2 cm, P < 0.03), waist-hip ratio (0.90 +/- 0.02 vs. 0.88 +/- 0.01, P < 0.01) free androgen index (FAI) (26.6 +/- 6.1 vs. 16.6 +/- 4.1, P < 0.01), testosterone [4.6 +/- 0.4 vs. 3.1 +/- 0.3 nmol/l (132.7 +/- 11.5 vs. 89.4 +/- 8.65 ng/dl), P < 0.01] and insulin resistance as measured by the homeostasis model assessment (HOMA) method (4.4 +/- 0.5 vs. 3.4 +/- 0.4, P = 0.05). There was no change in any of these parameters in the metformin-treated group.


CONCLUSIONS
This study suggests that the weight loss through rimonabant therapy may be of use in patients with PCOS and appears superior to insulin sensitization by metformin in reducing the FAI and insulin resistance in obese PCOS patients treated over a 12-week period.
Sathyapalan
Thozhukat
T
Department of Diabetes and Endocrinology, University of Hull, Hull, UK. tsathyapal@rediffmail.com
Cho
Li Wei
LW
Kilpatrick
Eric S
ES
Coady
Anne-Marie
AM
Atkin
Stephen L
SL
D000328:Adult; D005260:Female; D006801:Humans; D017588:Hyperandrogenism / Q000188:drug therapy*; D007333:Insulin Resistance / Q000502:physiology; D008687:Metformin / Q000627:therapeutic use*; D010880:Piperidines / Q000627:therapeutic use*; D011085:Polycystic Ovary Syndrome / Q000188:drug therapy*; D011720:Pyrazoles / Q000627:therapeutic use*; D000077285:Rimonabant; D013739:Testosterone / Q000097:blood; D015431:Weight Loss / Q000187:drug effects
D010880:Piperidines; D011720:Pyrazoles; D013739:Testosterone; D008687:Metformin; D000077285:Rimonabant