Estimation of Liver Fat by FibroScan in Patients With Nonalcoholic Fatty Liver Disease

Abstract

BackgroundAssessment of nonalcoholic fatty liver disease (NAFLD) includes estimation of liver fat (steatosis).Controlled attenuation parameter (CAP) value obtained by FibroScan ® (Echosens, Paris, France) is an alternative to liver biopsy for diagnosing and estimating steatosis (S). This study aimed to estimate the liver fat by CAP in NAFLD patients. MethodsAn observational cross-sectional study was conducted at the Liver Unit of Bir Hospital, from January 2021 to May 2021 after ethical clearance from the Institutional Review Board of the National Academy of Medical Sciences. A convenient sampling method was used. Data were analyzed with descriptive and inferential statistics involving bivariate and multivariate analysis. ResultsA total of 127 NAFLD patients were enrolled. The mean (±SD) CAP value was 271.53 (±50.69) dB/m. Total cholesterol, triglyceride, and body mass index (BMI) correlated positively (p<0.05) while systolic blood pressure correlated negatively with CAP value (p=0.031). On multivariate analysis, patients with BMI ≥25 kg/m 2 were found 3.7 times more likely to have CAP ≥291 dB/m (S3, severe steatosis) than those with BMI <25 kg/m 2 (p=0.048, 95% CI 1.01, 13.50). The mean (±SD) CAP values were 276.19 (±49.93) and 246.60 (±48.50) dB/m among those with BMI ≥25 kg/m 2 and <25 kg/m 2 , respectively (p=0.016, using independent ttest). CAP steatosis grading correlated positively with both the ultrasound grading (p<0.001) and fibrosis grading by liver stiffness measurement (p=0.004). ConclusionIn this observational cross-sectional study of NAFLD patients, the mean (±SD) CAP value was 271.53 (±50.69) dB/m, which corresponds to moderate steatosis (S2). Obese NAFLD patients with ≥25 kg/m 2 were 3.7 times more likely to have severe steatosis (S3) than nonobese NAFLD patients with BMI <25 kg/m 2 .