The Value of Five Novel Anthropometric Indicators in Evaluating MASLD and Liver Fibrosis in MASLD: A Cross-Sectional Study.

Background: Metabolic dysfunction-associated fatty liver disease (MASLD) is the most prevalent chronic liver disease globally. Early screening is critical for preventing liver fibrosis (LF) and cirrhosis, but liver biopsy and imaging are costly and less accessible in primary care settings. Simple, economical anthropometric indicators are urgently needed for large-scale initial screening. Methods: Using data from NHANES 2017-2020, we applied logistic regression, generalized additive models, and ROC analysis to evaluate five novel anthropometric indices (BRI, LAP, WTI, WWI, and ABSI) for predicting MASLD and LF in individuals with MASLD. Results: All indices showed significant positive dose-response associations with MASLD risk (fully adjusted ORs: BRI, 1.86; LAP, 1.03; WTI, 5.31; WWI, 3.31; and ABSI, 2.13). BRI and LAP demonstrated the highest predictive performance for MASLD (AUC = 0.82). For LF among individuals with MASLD, BRI (AUC = 0.71) outperformed FIB-4 and APRI. Stratified analyses revealed sex-, age-, and BMI-related differences: WTI performed better in women; ABSI and BRI in men; WWI, ABSI, and BRI in younger adults; and BRI in lean individuals. Nonlinear associations with MASLD were observed for all indices, whereas only WWI showed a linear association with LF. Conclusions: BRI is independently associated with MASLD and LF in individuals with MASLD and demonstrates superior predictive performance and clinical net benefit compared with other noninvasive models. These findings support its potential use for the early identification of MASLD and LF risk in primary care settings.