Visceral Adiposity Index (VAI) Levels and Metabolic Risk Across Phenotypes of Polycystic Ovary Syndrome (PCOS)

Background and Objectives: Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder often associated with metabolic disturbances such as insulin resistance and metabolic syndrome (MetS). Visceral adiposity index (VAI) is a validated marker that reflects visceral fat distribution and cardiometabolic risk. This study aimed to compare VAI levels among different PCOS phenotypes to evaluate cardiometabolic risk across these phenotypes. Materials and Methods: This prospective case–control study included 180 PCOS patients and 51 healthy controls without any metabolic or reproductive issues. Patients were divided into the following subtypes based on the Rotterdam criteria: Phenotype A (n = 96), clinical and/or biochemical hyperandrogenism (HA) + oligo-anovulation (OA) + polycystic ovarian morphology (PCOM); Phenotype B (n = 19), HA + OA; Phenotype C (n = 35), HA + PCOM; and Phenotype D (n = 30), OA + PCOM. VAI was calculated for women using anthropometric and biochemical parameters. Results: In the total PCOS group, VAI levels were significantly higher than in controls (p < 0.001). Phenotypes A and B had higher VAI values than controls and also higher in Phenotype A than in Phenotypes C and D (p = 0.003 and p = 0.001, respectively). While present in 38 patients (21.10%) in the PCOS group, there was no metabolic syndrome (MetS) in controls (p < 0.001). In Phenotypes A, B, and D, while more patients had MetS than controls (p < 0.001, 0.004, and 0.021, respectively), more patients had MetS in Phenotype A compared to Phenotypes C and D (p = 0.003 and p = 0.021, respectively). Given ROC analysis, the VAI cut-off value in predicting MetS in the PCOS group was 1.66 (sensitivity = 94.74% and specificity = 83.10%). Conclusions: PCOS phenotypes characterized by HA and OA, particularly Phenotypes A and B, are associated with higher VAI values and an increased frequency of MetS risk. Early identification of these phenotypes may facilitate the implementation of targeted metabolic risk reduction and early intervention strategies, thereby contributing to the reduction of cardiovascular risk.