A Noninvasive Scoring System for Liver Fibrosis in Patients With Metabolic Dysfunction-Associated Fatty Liver Disease

Background and Aims: Metabolic dysfunction-associated fatty liver disease (MAFLD) is diagnosed in patients with hepatic steatosis who meet at least one of the following criteria: body mass index >25, diabetes mellitus type 2, and metabolic dysfunction. Given about one-third of Americans meet the criteria for MAFLD, there is an unmet need for a score to noninvasively triage patients who need transient elastography and possible biopsy. We determined the risk factors for advanced fibrosis (F3+ on transient elastography) in a cohort of 2671 MAFLD patients and developed the MAFLD fibrosis-4 (FIB-4) score to help clinicians predict the risk of advanced fibrosis. Methods: Multivariate logistic regression analysis and independent t-tests were used to evaluate the relationship between physical exam parameters, lab values, and interview responses and risk of advanced fibrosis. The most significant risk factors were used to build the MAFLD FIB-4 score, equivalent to −46.55 + (7.89∗log[waist circumference]) + (1.25∗log[fasting plasma glucose]) + (0.85∗FIB-4 score). Results: Risk factors for advanced fibrosis in MAFLD patients are elevated body mass index (odds ratio [OR] = 5.90; P <.01), waist circumference (OR = 3.53; P <.01), high fasting plasma glucose (OR = 2.45; P <.01), high homeostasis model assessment-estimated insulin resistance score (OR = 2.18; P =.02), high triglycerides (OR = 1.94; P =.03), positive hepatitis C RNA (OR = 14.92; P =.02), high ferritin (OR = 1.58; P =.05), and alanine transaminase > aspartate aminotransferase (OR = 1.54; P =.04). The MAFLD FIB-4 score has a specificity of 80%, sensitivity of 97%, and receiver operating characteristic of 0.85 (compared to the receiver operating characteristic of 0.60 for FIB-4 and 0.68 for nonalcoholic fatty liver disease existing scores) for the detection of advanced fibrosis in MAFLD patients. Conclusion: Clinicians can utilize the MAFLD FIB-4 score to noninvasively identify patients with advanced fibrosis risk for further evaluation and management.