Diagnostic Accuracy of the Non-Invasive Markers Nfls, Ni-Nash-Ds, and Fib-4 for Assessment of Different Aspects of Non-Alcoholic Fatty Liver Disease in Individuals With Obesity: Cross-Sectional Study

Abstract

Background: Non-invasive markers have been developed to assess the presence and severity of liver abnormalities related to non-alcoholic fatty liver disease (NAFLD). Objective: To analyze the diagnostic accuracy of non-invasive NAFLD markers (NAFLD liver fat score [NLFS], non-invasive non-alcoholic steatohepatitis detection score [NI-NASH-DS] and fibrosis score based on four variables [FIB-4]) in individuals with obesity undergoing bariatric surgery. Methods: A descriptive retrospective cross-sectional study was carried out enrolling 91 individuals who underwent bariatric surgery at a tertiary-level public university hospital. Non-invasive NAFLD markers were calculated using laboratory tests, clinical and anthropometric variables and diagnostic accuracy tests were calculated comparing them in relation to the gold-standard test for this analysis (histopathological evaluation). Results: A total of 85.7% of the participants were female and mean age was 39.1±9.8 years. The average body mass index was 38.4±3.6 kg/m2. At histopathological examination, 84 (92.3%) patients presented with steatosis, 82 (90.1%) with some type of fibrosis; 21 (23.1%) patients were diagnosed with NASH according to the NAFLD activity score criteria. The overall accuracy of NLFS score was 58.2% for general hepatic steatosis and 61.5% for moderate to severe steatosis. The overall accuracy of FIB-4 was 95.4% for advanced fibrosis. NI-NASH-DS had a 74.7% overall accuracy for NASH. Conclusion: In a population of individuals with obesity, the FIB-4 score had high overall accuracy in assessing the presence of advanced liver fibrosis, whereas the NFLS and NI-NASH-DS had moderate accuracies for the assessment of steatosis and NASH, respectively.