RESUMO
INTRODUCTION: We conducted a pilot project to test the hypothesis that decreasing insulin concentrations with diazoxide would affect parameters of vitamin D in obese women with and without polycystic ovary syndrome (PCOS). MATERIALS AND METHODS: Eight obese women with PCOS and nine matched controls participated in the study. Diazoxide was administered orally 100 mg three times daily for 10 days, and parameters of vitamin D were measured at baseline and end-of-study. RESULTS: At baseline, women with polycystic ovary syndrome had significantly lower serum 25-hydroxyvitamin D (25[OH]D) levels than controls. After treatment with diazoxide, there were no significant changes in vitamin D parameters when PCOS and control women were evaluated separately. Diazoxide exhibited differential effects on 25(OH)D concentrations in PCOS as compared with normal women (P for interaction=0.045), and serum 25(OH)D levels converged after diazoxide treatment. CONCLUSIONS: Obese women with PCOS had significantly lower serum 25(OH)D levels at baseline than age- and body mass index-matched controls. Short-term administration with diazoxide seemed to have differential effects on 25(OH)D levels in PCOS as compared with control women. Further studies are necessary to confirm this finding.