Performance of insulin resistance indices for identifying metabolic dysfunction-associated steatotic liver disease in women with polycystic ovary syndrome: a retrospective cross-sectional study

Metabolic dysfunction-associated steatotic liver disease (MASLD) is highly prevalent in women with polycystic ovary syndrome (PCOS), largely driven by insulin resistance. However, the comparative discriminative performance of different insulin resistance–related surrogate indices in this population remains unclear. This study aimed to evaluate and compare the ability of the triglyceride–glucose (TyG) index, TyG-body mass index (TyG-BMI), and metabolic score for insulin resistance (METS-IR) to identify MASLD in women with PCOS. This retrospective observational study included 984 women with PCOS, of whom 392 were diagnosed with MASLD. Multivariable logistic regression was used to assess independent associations between insulin resistance-related indices and MASLD. Receiver operating characteristic (ROC) curve analysis was performed to evaluate discriminatory performance, and DeLong’s test was used to compare differences in area under the curve (AUC). All three insulin resistance–related indices were independently associated with MASLD in women with PCOS. METS-IR showed the numerically highest discriminatory ability (AUC = 0.934, 95% CI: 0.920–0.948), followed by TyG-BMI (AUC = 0.929, 95% CI: 0.914–0.943), while the TyG index demonstrated lower performance (AUC = 0.739, 95% CI: 0.709–0.770). DeLong’s test showed that both METS-IR and TyG-BMI had significantly higher AUCs than the TyG index (both P < 0.001), whereas the difference between METS-IR and TyG-BMI was not statistically significant ( P = 0.096). METS-IR and TyG-BMI exhibit superior discriminative performance compared with the TyG index for identifying MASLD in women with PCOS, while their performance is comparable to each other. These indices may provide simple and practical approaches for cross-sectional identification of MASLD and metabolic risk stratification in women with PCOS. Not applicable.