Comparison of Fibrosis-4 with FibroScan for Liver Fibrosis Assessment in Non-Alcoholic Fatty Liver Disease Patients: A Cross-sectional Study

Objective: To compare the efficacy and accuracy of the Fibrosis-4 (FIB-4) index with FibroScan in assessing liver fibrosis in patients with non-alcoholic fatty liver disease (NAFLD). Methods: This cross-sectional study was conducted at Patel Hospital, Karachi, Pakistan, from October 2023 to April 2024. All known cases of NAFLD or non-alcoholic steatohepatitis (NASH) aged ≥18 years, regardless of gender, were included. FIB-4 scores were measured using age, platelet level, aspartate transaminase (AST), and alanine transaminase (ALT). FibroScan categorized liver fibrosis into stages F0 to F4 with specific stiffness ranges: F0 (1–6 kPa), F1 (6.1–7 kPa), F2 (7.1–9 kPa), F3 (9.1–10.3 kPa), and F4 (≥10.4 kPa). Results: Of the 146 patients, the median age was 52.00 (IQR: 47.00–54.00) years. Based on FibroScan results, 61 (41.8%) patients were classified as F1, 35 (24.0%) as F2, 30 (20.5%) as F3, and 20 (13.7%) as F4. The diagnostic performance of FIB-4 showed an area under the curve of 0.83 (95% CI: 0.76–0.90). The optimal cut-off for FIB-4 was 1.28 with sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy of 98.0%, 65.6%, 59.7%, 98.4%, and 76.7%, respectively. Spearman's correlation test (ρ) was applied and a significantly moderate correlation was found between FibroScan and FIB-4 (ρ = 0.50, p < 0.001). Conclusion: FIB-4 demonstrated higher accuracy and diagnostic performance in determining liver fibrosis in NAFLD patients compared to FibroScan.