Relationship between controlled attenuation parameter and hepatic steatosis as assessed by ultrasound in alcoholic or nonalcoholic fatty liver disease

Background/Aims: The aim of this study was to evaluate the relationship between controlled attenuation parameter (CAP) and hepatic steatosis, as assessed by ultrasound (US) in patients with alcoholic liver disease (ALD) or non-alcoholic fatty liver disease (NAFLD). Methods: Patients with either ALD or NAFLD who were diagnosed with fatty liver with US and whose CAP scores were measured, were retrospectively enrolled in this study. The degree of hepatic steatosis assessed by US was categorized into mild (S1), moderate (S2), and severe (S3). Results: A total of 186 patients were included: 106 with NAFLD and 80 with ALD. Regarding hepatic steatosis, the CAP score was significantly correlated with US (ρ=0.580, p<0.001), and there was no significant difference between the NAFLD and ALD groups (ρ=0.569, p<0.001; ρ=0.519, p<0.001; p=0.635). Using CAP, area under receiver operating characteristic curves for ≥S2 and ≥S3 steatosis were excellent (0.789 and 0.843, respectively). For sensitivity ≥90%, CAP cutoffs for the detection of ≥S2 and ≥S3 steastosis were separated with a gap of approximately 35 dB/m in all patients and in each of the NAFLD and ALD groups. Conclusions: The CAP score is well correlated with hepatic steatosis, as assessed by US, in both ALD and NAFLD.