Diagnostic Accuracy and Optimal Cut-off of Controlled Attenuation Parameter for the Detection of Hepatic Steatosis in Indian Population

Background And Aims: Ultrasound of the liver is not good to pick up mild steatosis. Controlled attenuation parameter (CAP) evaluated in transient elastography (FibroScan) is widely available in India. However, data regarding the diagnostic accuracy and optimal cut-off values of CAP for diagnosing hepatic steatosis are scarce in Indian population. MRI-PDFF is an accurate technique for quantifying hepatic steatosis. Thus, this study examined the diagnostic accuracy and optimal cut-off values of CAP for diagnosing steatosis with MRI-PDFF as reference standard.

Methods: A total of 137 adults underwent CAP and MRI-PDFF measurements prospectively. A subset of participants (n = 23) underwent liver biopsy as part of liver transplantation evaluation. The optimal cut-off values, area under the receiver operating characteristic (AUROC) curves, sensitivity, and specificity for CAP in detecting MRI-PDFF ≥5% and ≥10% were assessed.

Results: The mean age and body mass index (BMI) were 44.2 ±10.4 years and 28.3 ±3.9 kg/m, respectively. The mean hepatic steatosis was 13.0 ±7.7% by MRI-PDFF and 303 ±54 dB/m by CAP. The AUROC of CAP for detecting hepatic steatosis (MRI-PDFF ≥5%) was 0.93 (95% CI, 0.88-0.98) at the cut-off of 262 dB/m, and of MRI-PDFF ≥10% was 0.89 (95% CI, 0.84-0.94) at the cut-off of 295 dB/m. The CAP of 262 dB/m had 90% sensitivity and 91% specificity for detecting MRI-PDFF ≥5%, while the CAP of 295 dB/m had 86% sensitivity and 77% specificity for detecting MRI-PDFF ≥10%.

Conclusions: The optimal cut-off of CAP for the presence of liver steatosis (MRI-PDFF ≥5%) was 262 dB/m in Indian individuals. This CAP cut-off was associated with good sensitivity and specificity to pick up mild steatosis.