Serum uric acid levels in patients with different phenotypes of polycystic ovary syndrome.

Background & objectives Polycystic ovary syndrome (PCOS) is a common endocrinopathy in reproductive-aged women, frequently associated with insulin resistance, obesity, and increased cardiovascular risk. Serum uric acid, linked to oxidative stress and endothelial dysfunction, may contribute to the cardiometabolic complications of PCOS. Although hyperuricemia is common in PCOS, differences in serum uric acid among phenotypes remain unclear. This study compared serum uric acid across PCOS phenotypes, hypothesising that classic, obese phenotypes would exhibit higher levels due to synergistic metabolic and hormonal effects. Methods A total of 180 women with PCOS [phenotypes A(n=96), B (n=19), C (n=35), and D (n=30)] and 51 age-matched controls were included. PCOS was diagnosed according to the revised 2003 Rotterdam criteria, and phenotyping was based on the presence of hyperandrogenism, oligo-anovulation, and polycystic ovarian morphology. Fasting serum uric acid levels were measured using the uricase method, and hyperuricemia was detected as ≥6.0 mg/dL. Analyses were performed using the Shapiro-Wilk test for normality, Levene's test for homogeneity, and appropriate parametric or non-parametric tests with Holm correction for multiple comparisons. Results Among 231 women evaluated, age distributions were similar between groups. Median body mass index (BMI) and waist circumference (WC) were higher in the PCOS cohort, most prominently in Phenotype A (both P<0.001). Serum uric acid was significantly higher in Phenotype A [4.8 (2.7-8.9) mg/dL] than in controls [4.1 (2.7-6.3) mg/dL] and Phenotype C [4.2 (2.6-5.8) mg/dL] (both P<0.001). Hyperuricemia was more frequent in PCOS than in controls (P=0.035), occurring predominantly in Phenotype A. Most hyperuricemic patients were obese; notably, no obese controls were available for comparison. Serum uric acid levels were positively associated with BMI (Spearman rho=0.452, +) and WC (0.412, P<0.001), yet in BMI categories, no significant differences were found in serum uric acid among phenotypes. Interpretation & conclusions Among PCOS patients, elevated serum uric acid is significantly associated with the classic hyperandrogenic phenotype (Phenotype A) and may also be related to obesity, emphasising the importance of monitoring serum uric acid in obese classical PCOS females, particularly those presenting with Phenotype A.