Transient Elastography (Fibroscan) Compared to FIB-4, APRI, and AST/ALT Ratio for Assessment of Liver Significant Fibrosis in Patients With Nonalcoholic Fatty Liver Disease

Abstract

Introduction: Non alcoholic fatty liver disease (NAFLD) is the second most common cause of liver cirrhosis affecting up to 100 million population in the United States. Serum tests such Fibrosis-4 index (FIB-4), aspartate to platelet ratio (ARPI) and aspartate transaminase to alanine transaminase ratio (AST/ALT) compared with transient elastography (TE) have not been well studied. Our aim is to compare the staging of significant fibrosis by TE with serums tests. Methods: Our study is a retrospective cross sectional study that reviewed a total of 195 patients with NAFLD from March 2014-March 2017. Groups were divided based on liver stiffness measurement (LSM) of non significant fibrosis F0-F1 (kpa <7.5) and significant fibrosis F2-F4 (kpa >7.5). Statistical analysis was performed using SPSS 21. Data were expressed as mean ± standard deviation. The correlation between non-invasive tests and transient elastography was tested using the nonparametric Spearman's correlation coefficient. Areas under the receiver operating characteristics curves (AUROC) and the 95% confidence intervals (CI) of the AUROC values were calculated for detection of significant fibrosis. Results: The population were predominantly white (54%) and males (60%) with a mean age of 51 years. The mean body mass index (BMI) was 31.2. In our study 30% and 39% patients had diabetes and hypertension respectively while 25% had hyperlipidemia. Obese patients (BMI>30) had more significant fibrosis compared to non-obese (BMI <30) pts (p=0.001). FIB-4, APRI and AST/ALT ratio correlated significantly with fibroscan score(r=0.472, p<0.0001;r=0.418, p<0.0001;r =0.219, p=0.003). Area under the ROC curve (AUROCs) of FIB-4, APRI and AST/ALT were 0.705, 0.644 and 0.643 for significant fibrosis (according to 7.5kpa). FIB-4 had a higher accuracy for the prediction of singifiant fibrosis (p<0.0001) and APRI and AST/ALT ratio had a intermittent accuracy (p=0.002, p=0.003, respectilvy). Conclusion: In NAFLD patients, all serum tests (FIB-4, APRI, AST/ALT) showed correlation with LSM by TE with the FIB-4 being the most accurate to assess significant fibrosis compared to APRI and AST/ALT ratio. Considering the risks of liver biopsy, usage of serum tests can be a helpful diagnostic tool to identify patients with higher risk of significant fibrosis taking into account overall clinical condition and additional tests like transient elastography.988_A Figure 1. Distribution of ethnic groups in study population988_B Figure 2. General characteristics of study population988_C Figure 3. The Area Under an ROC Curve (AUROC) for FIB-4, APRI, AST/ALT