Elevated Serum Fibroblast Growth Factor 21 and Associated Metabolic Dysregulation in Polycystic Ovary Syndrome: A Case–Control Study

Objective: Polycystic ovary syndrome (PCOS) is a prevalent endocrine disorder that not only disrupts reproductive function but is also associated with significant metabolic and hepatic disturbances. This case–control study aimed to compare metabolic and liver function parameters between women with PCOS and healthy controls, with a focus on the potential role of fibroblast growth factor 21 (FGF21) as a diagnostic biomarker. Methods: Participants were selected according to the Rotterdam criteria and included age- and BMI-matched women with PCOS and healthy controls. Fasting blood samples were collected from all subjects to measure serum lipid profiles, liver enzymes, and FGF21 concentrations. Standard enzymatic colorimetric assays were used for lipid measurements, while liver enzymes were determined via spectrophotometric methods. Circulating FGF21 levels were quantified using a commercially available ELISA kit. Results PCOS patients exhibited significantly higher serum FGF21 levels (122 ± 42.3 ng/mL) compared to controls (63.5 ± 21.5 ng/mL, p < 0.001). ROC curve analysis identified an optimal FGF21 cutoff value of approximately 87.78 ng/mL, yielding a sensitivity of 91% and specificity of 90% for PCOS diagnosis. Conclusion The study reinforces the association of PCOS with distinct metabolic and hepatic abnormalities. The elevated levels of FGF21 in PCOS patients may reflect a compensatory response to metabolic stress and point to its promise as a novel diagnostic marker. These findings highlight the importance of comprehensive metabolic screening in PCOS and may inform future therapeutic approaches.