Publication:

Leptin and LH/FSH ratio as independent predictors of polycystic ovary syndrome in normoglycemic women: a case-control study

Background Polycystic ovary syndrome (PCOS) is a multifaceted disorder characterized by reproductive, metabolic, and endocrine disturbances. While insulin resistance (IR) is recognized as a central feature, the interplay of adipokines, lipid metabolism, gonadotropin imbalance, and inflammation in normoglycemic PCOS women remains underexplored.

Methods A case-control study was conducted on 30 newly diagnosed normoglycemic women with PCOS (Rotterdam criteria, 2003) and 30 age-matched healthy controls. Anthropometric, hormonal (LH, FSH, LH/FSH ratio, prolactin, estrogen, progesterone, testosterone), metabolic (fasting glucose, HbA1c, insulin, HOMA-IR), lipid (cholesterol, triglycerides, HDL), adipokine (leptin), and hematological parameters were assessed. Group comparisons were performed using independent t-test/Mann-Whitney test as appropriate. Correlation analysis explored inter-relationships among variables, and multivariate logistic regression identified independent predictors of PCOS.

Results Compared with controls, PCOS women had significantly higher BMI (26.3±5.3 versus 23.4±3.2 kg/m2; p=0.014), WHR (0.861±0.061 versus 0.799 ±0.060; p<0.001), LH (7.5±3.7 versus 5.3±2.2 mIU/ml; p=0.006), LH/FSH ratio (1.37±0.76 versus 0.76±0.32; p<0.001), estrogen (54.5±18.2 versus 38.0±11.1 pg/ml; p<0.001), testosterone (49.7±25.1 versus 34.5±14.0 ng/dl; p=0.001), fasting insulin (11.55±10.8 versus 5.63±2.6 uIU/ml; p=0.004), HOMA-IR (2.47±2.4 versus 1.17±0.54; p=0.007), and leptin (31.3±17.4 versus 16.4±10.5 ng/ml; p<0.001), with significantly lower FSH (5.6±1.7 versus 7.2±1.9 mIU/ml; p<0.001) and HDL (43.0±10.0 versus 54.3±15.3 mg/dl; p<0.001). Correlation analysis revealed positive associations between BMI and leptin, insulin, and HOMA-IR; WHR and testosterone; TLC and leptin/WHR; and LH/FSH ratio and estrogen, while HDL correlated negatively with HOMA-IR and TLC. Logistic regression identified leptin (OR=1.105, 95% CI 1.016-1.201, p=0.020) and LH/FSH ratio (OR=18.48, 95% CI 1.82-187.7, p=0.014) as independent predictors of PCOS.

Conclusions Normoglycemic PCOS women show distinct hormonal, metabolic, and adipokine alterations, with leptin and LH/FSH emerging as robust independent predictors. These findings highlight the early convergence of adiposity, insulin resistance, inflammation, and gonadotropin imbalance in PCOS, underscoring the need for early biomarker-based risk stratification and intervention even before the onset of overt glycemic abnormalities.