SAT382 Lean Mass and Associated Factors in Women with PCOS with Different Phenotypes

Disclosure: T.M. Fighera: None. B.R. Santos: None. P.M. Spritzer: None. Introduction: Obesity, insulin resistance and hyperandrogenism are common findings in women with PCOS. These abnormalities have been associated with muscle mass changes reported in previous studies, with conflicting results comparing women with PCOS versus non-PCOS controls. The aim of the present study was to evaluate clinical and laboratory variables related to lean body mass according to PCOS phenotype. METHODS: In this case-control study, we analyzed 133 women of reproductive age, recruited through public advertisement at the outpatient clinic of a University Hospital. Inclusion criteria were body mass index (BMI) ranging from 18.5 to 39.9 kg/m², age between 17 and 35 years and no intake of drugs known to interfere with hormone levels for at least 3 months before the study. Women with diabetes, thyroid dysfunction, liver or renal disease were excluded. PCOS was defined according to the Rotterdam Consensus. The study protocol was approved by the local Ethics Committee, and written informed consent was obtained from all participants. Blood pressure, BMI, body composition by dual-energy X-ray absorptiometry (DXA), and laboratory measurements for metabolic and hormonal variables were performed in all subjects. Creatinine values were used as an indirect marker of lean mass. RESULTS: Median age was 28 years (23-31), and the median BMI was 27.9kg/m² (24.1-33.7), with higher BMI in women with the AB phenotype of PCOS (n=59) compared to ovulatory (C phenotype) PCOS (n=23) and controls (n=51) (p=0.005). Women with the AB phenotype of PCOS presented higher Ferriman-Gallway score (p<0.001), systolic (p=0.001) and diastolic blood pressure (p=0.002), insulin levels (p=0.006), Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (p=0.008), metabolic syndrome prevalence (p<0.001), testosterone (p=0.008), free androgen index (FAI) (p<0.001), fat mass index (FMI) (0.015), and android-to-gynoid (AG) fat ratio (p=0.036) compared to controls. Appendicular lean mass index (ALMI) was higher in the AB phenotype than controls [7.01 (6.33-8.02) vs 6.69 (5.94-7.09), p= 0.024] and the C phenotype [6.60 (6.16-7.22), p=0.022]. A positive correlation was observed between ALMI and creatinine, even after adjustment to BMI, in women with AB phenotype (rho=0.319, p=0.023), but not with ovulatory PCOS (rho=0.293, p=0.238) or controls (rho=0.277, p=0.097). In a multivariate linear regression model, creatinine, HOMA-IR, and FMI were positively associated with ALMI, explaining 38.4% of the variation in lean mass. CONCLUSIONS: The present results suggest that the higher lean mass observed in women with the AB phenotype of PCOS is associated with hyperinsulinemia and higher fat mass. Sources of research support: INCT/CNPq and FAPERGS Presentation Date: Saturday, June 17, 2023