Racial influence on the polycystic ovary syndrome phenotype: A black and white case-control study

Objective: To estimate racial disparities in the polycystic ovary syndrome (PCOS) phenotype between white and black women with PCOS. Design: Case-control study. Setting: Two academic medical centers. Patient(s): A total of 242 women not taking confounding medications in otherwise good health. Intervention(s): Phenotyping during the follicular phase or anovulation after an overnight fast in women. Main outcome measure(s): Biometric, serum hormones, glycemic and metabolic parameters, and body composition by dual-energy x-ray absorptiometry. Result(s): We studied 77 white and 43 black women with PCOS and 35 white and 87 black controls. Black women with PCOS were similar reproductively to white women with PCOS. Black women with PCOS had lower levels of serum transaminases, higher high-density lipoprotein cholesterol levels (mean difference [MD], 18.2 mg/dL; 95% confidence intervals [CI], 14.3, 22.1 mg/dL), lower triglyceride levels (MD, -43.2 mg/dL; 95% CI, -64.5, -21.9), and enhanced insulinogenic index on the oral glucose tolerance test compared with white women with PCOS. Black women with PCOS had higher bone mineral density (MD, 0.1 g/cm²; 95% CI, 0.1, 0.2 g/cm²), lower percent body fat on dual-energy x-ray absorptiometry (MD, -2.8%; 95% CI, -5.1%, -0.5%), and overall a higher quality of life. Although most of these findings disappeared when the differences with racially matched controls were compared, black women with PCOS compared with black controls had lower estradiol levels than white women with PCOS compared with white controls (MD, -12.9 pg/mL; 95% CI, -24.9, -0.8 pg/mL), higher systolic blood pressure (MD, 9.1 mm Hg; 95% CI, 0.8, 17.4 mm Hg), and lower fasting glucose levels (MD, -12.0 mg/dL; 95% CI, -22.3, -1.7 mg/dL). Conclusion(s): Racial disparities in PCOS phenotype are minor and mixed. Future studies should explore if race impacts treatment effects.