Serum uric acid concentration as non-classic cardiovascular risk factor in women with polycystic ovary syndrome: effect of treatment with ethinyl-estradiol plus cyproterone acetate versus metformin

BACKGROUND: Serum uric acid levels have emerged as a cardiovascular risk factor, and interventions aimed to decrease its level have been related with an improvement in clinical and non-clinical cardiovascular outcomes. METHODS: Serum uric acid levels were measured in 40 polycystic ovary syndrome (PCOS) patients and 40 non-hyperandrogenic women matched for BMI and grade of obesity, and were followed-up in 34 PCOS patients who were randomized to an oral contraceptive containing 35 mg ethinyl-estradiol plus 2 mg cyproterone acetate (Diane(35) Diario) or metformin (850 mg twice daily) for 24 weeks. RESULTS: There were no statistically significant differences in uric acid levels between PCOS and non-hyperandrogenic control women. Considering all PCOS and non-hyperandrogenic control women as a whole, obese women showed higher uric acid concentrations than lean and overweight women, and the main determinant of serum uric acid level was the BMI. In PCOS women, Diane(35) Diario treatment was related with a decrease in uric acid levels (P = 0.018), whereas no changes were observed with metformin. CONCLUSIONS: Obesity is the main determinant of serum uric acid concentrations in PCOS patients, yet amelioration of androgen excess with an antiandrogenic contraceptive pill results in a significant decrease in these levels, an effect that is not observed with metformin. ClinicalTrials.gov NLM Identifier: NCT00428311.