Diagnostic Value of the Triglyceride-Glucose Index in Predicting Metabolic Syndrome in Women with Polycystic Ovary Syndrome

Background: Polycystic ovary syndrome (PCOS) is associated with a high risk of metabolic syndrome (MetS), increasing cardiovascular complications. The Triglyceride-Glucose (TyG) index is a simple marker of insulin resistance, but its utility in predicting MetS in Vietnamese PCOS patients is underexplored. Methods: A cross-sectional study was conducted on 105 women diagnosed with PCOS (Rotterdam criteria) at Da Nang Hospital of Women and Children from September 2019 to June 2020. Clinical parameters, lipid profiles, glucose, and TyG index (calculated as ln[Triglycerides × Glucose/2]) were assessed. MetS was diagnosed following the IDF 2006 criteria. Data were analyzed using SPSS 20.0 and MedCalc 12.5, with p < 0.05 considered significant. Results: Mean TyG index was 8.98 ± 0.61. TyG was higher in women ≥35 years (9.16 ± 0.58 vs. 8.84 ± 0.61, p = 0.043), those with hypertension (9.41 ± 0.36 vs. 8.77 ± 0.59, p < 0.05), and those with MetS (9.73 ± 0.59 vs. 9.29 ± 0.47, p < 0.05). TyG predicted MetS with an AUC of 0.772, sensitivity of 83.3%, specificity of 64%, and cut-off >8.895, outperforming individual MetS components. Conclusion: The TyG index is a valuable, cost-effective tool for predicting MetS in Vietnamese women with PCOS, supporting early screening and intervention to reduce cardiovascular risk.