Accuracy of Noninvasive Fibrosis Scoring Systems in African American and White Patients With Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease fibrosis score (NFS), fibrosis-4 (FIB-4) score, aspartate aminotransferase (AST)-to-platelet ratio index (APRI) score, and AST–alanine aminotransferase (ALT) ratio are noninvasive fibrosis scoring systems for the staging of liver fibrosis in patients with chronic liver disease. METHODS: In a large cohort of patients with nonalcoholic fatty liver disease, we compared AST–ALT ratio, NFS, FIB-4 score, and APRI score in predicting advanced fibrosis (defined as fibrosis stage ≥ 3) in histologically confirmed African American (AA) and white patients. We identified 907 patients: 677 (74.6%) white and 230 (25.3%) AA patients with nonalcoholic fatty liver disease. RESULTS: Of the 907 patients, 115 (12.8%) patients had advanced fibrosis (stages 3 and 4) in the total cohort: 6 (2.6%) AAs, and 109 (16.2%) whites. In AAs, the area under the receiver operating characteristic (area under the curve) for predicting advanced fibrosis was 0.58 by NFS, 0.86 by APRI score, 0.77 by FIB-4 score, and 0.65 by AST–ALT ratio. In whites, the area under the receiver operating characteristic for predicting advanced fibrosis was 0.82 by NFS, 0.82 by APRI score, 0.88 by FIB-4 score, and 0.76 by AST–ALT ratio. In the AA population, NFS > 0.675, FIB-4 score > 2.67, and APRI score > 1.5 each has a negative predictive value of 98%, whereas the negative predictive values in whites are 91%, 88%, and 85%, respectively. DISCUSSION: Noninvasive fibrosis scoring systems can reliably exclude advanced fibrosis in both AAs and whites and have acceptable discriminatory ability to predict advanced fibrosis in whites. The utility of noninvasive fibrosis scoring systems in predicting advanced fibrosis in AAs needs further validation in a larger multicenter cohort.