ETD

• Anthropometric indices
• Insulin resistance
• Metabolic syndrome
• Polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in women of reproductive age and is characterized by marked clinical, hormonal, and metabolic heterogeneity. Obesity, particularly central and visceral adiposity, plays a key role in modulating both the severity of the syndrome and the long-term cardiometabolic outcomes. However, body mass index (BMI), the most used marker of adiposity, often fails to adequately reflect fat distribution, especially in normal-weight women with PCOS. Therefore, alternative and complementary anthropometric indices have been proposed to better capture central obesity and cardiometabolic risk in this population.
The primary aim of this study was to evaluate which anthropometric indices show the strongest association with cardiometabolic risk factors in women with PCOS, with particular focus on the Body Roundness Index (BRI). Secondary objectives were to assess whether the predictive value of anthropometric measures was affected by age and to identify the most useful indices for detecting metabolic risk in normal-weight women with PCOS.
This retrospective, cross-sectional study included women aged 13–40 years diagnosed with PCOS according to the Rotterdam criteria. Clinical, anthropometric, hormonal, and metabolic data were collected at the time of diagnosis from medical charts of patients referred to the Gynecological Endocrinology Unit of the University of Pisa between 2015 and 2025. Different anthropometric indices and metabolic parameters were collected, and composite indices of cardiometabolic risk were calculted. Receiver operating characteristic (ROC) analyses were performed to compare the ability of anthropometric measures to predict metabolic alterations. Multivariate analysis of covariance and regression analyses were used to evaluate independent associations after adjustment for age.
A total of 245 women with PCOS were included in the analysis. Although approximately half of the population was overweight or obese, insulin resistance and hyperinsulinemia were present in only one quarter of patients. BMI, waist circumference, and BRI were all strongly associated with metabolic alterations. However, BMI showed a stronger association with glucose homeostasis, while waist-derived measures (particularly waist circumference and BRI) were superior predictors of metabolic syndrome and dyslipidemia. Women with higher BRI values exhibited significantly worse metabolic and hormonal profiles. Multivariate analyses confirmed that BRI and age both explained an independent proportion of cardiometabolic parameters, while BMI did not add incremental contribution beyond BRI in explaining the overall cardiometabolic risk. Both in total population and in the sub-group of normal-weight women with PCOS, BRI remained significantly associated with one or more of the cardiometabolic composite indices of risk considered, whereas BMI alone still failed to independently correlate to these indices. However, when all these analyses were performed using waist circumference instead of BRI, the results were similar in terms of significance.
In conclusion, BRI demonstrated better performance in identifying PCOS patients with higher cardiometabolic risk than BMI did, confirming the independent role of body shape and fat distribution over simple weight in defining risk. BRI's ability to identify metabolic syndrome and insulin resistance was similar to that of waist circumference, which is one of the criteria used to diagnose metabolic syndrome. However, BRI provides additional information into body shape and visceral fat accumulation, not just central obesity.
Overall, an integrated anthropometric approach combining traditional and novel indices is likely to provide the most accurate assessment of metabolic risk and support personalized management strategies in women with PCOS.