Waist Circumference as a Predictor of Hepatic Steatosis and Fibrosis in the NHANES 2017–2018 Cohort

PURPOSE: Steatotic liver disease (SLD) is a prevalent condition that can progress to fibrosis if untreated. The most commonly used screening tool for liver disease is the FIB-4 score, which can help rule out advanced liver fibrosis. This study aims to assess whether a simple tool such as waist circumference (WC) can screen for both hepatic steatosis and fibrosis. METHODS: This study was based on analysis of patient data from the NHANES 2017-2018 database, including WC, laboratory values, and Fibroscan data. Of 9254 participants, 6846 were excluded due to incomplete or missing lab and Fibroscan data (2408 included). Receiver operator characteristics (ROC) curve analyses assessed the performance of WC, fatty liver index (FLI), and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) in predicting steatosis at two cut-off points: controlled attenuation parameter (CAP) ≥248 dB/m and ≥294 dB/m. ROC analyses also compared WC and FIB-4 performance in predicting significant fibrosis based on liver stiffness measurement (LSM) cutoff: <8.2 kPa (F0-F1) or ≥8.2 kPa (F2-F4). Analyses were performed using JMP Pro version 17. RESULTS: WC was shown to be a strong predictor of steatosis and fibrosis among men and women. WC and FLI were comparable predictors for steatosis among men; however, FLI outperformed WC as a predictor of steatosis among women. WC and FLI were shown to be more effective predictors of steatosis in men and women at both CAP cutoff values when compared with HOMA-IR. All three measures were more predictive of steatosis in men than in women. In a subgroup analysis of 1053 participants ages 35-65 years, WC outperformed FIB-4 in predicting significant fibrosis. CONCLUSION: WC is an independent predictor of hepatic steatosis and fibrosis among US adults. WC should be measured routinely in primary care settings, facilitating earlier intervention for those at risk for liver steatosis and fibrosis.