Controlled attenuation parameter reflects steatosis in compensated advanced chronic liver disease

BACKGROUND & AIMS Controlled Attenuation Parameter (CAP) for steatosis assessment has not been validated in compensated advanced chronic liver disease cACLD. We primarily aimed at assessing the accuracy of CAP for the diagnosis and quantification of steatosis in cACLD. Secondary aim: to assess the validity of non-invasive criteria for cACLD according to liver stiffness measurement (LSM). METHODS This is a single center retrospective study including patients with cACLD defined as LSM ≥10 kPa, CAP measurement and liver biopsy (reference standard for steatosis and fibrosis) observed in 06/2015-06/2017. Steatosis was graded as S0 ( 66%). The diagnostic performance of CAP for any grade of steatosis and for high-grade steatosis (≥S2) was studied. RESULTS Among 461 consecutive patients, 111 with LSM-based diagnosis of cACLD were included (63% male, median age 55 yrs, median BMI 28.1 Kg/m2 , etiology: 32% NAFLD/NASH, 32% alcohol or viral +metabolic syndrome, 15% viral, 6% autoimmune, 4% alcohol, 11% others). Median LSM and CAP were 16.1 kPa and 277 dB/m, respectively. On liver biopsy, steatosis was found in 88/111 patients (79%); 44 patients (43 with metabolic syndrome) had high-grade steatosis. CAP was accurate in identifying any grade of steatosis (AUROC 0.847;95%CI 0.767-0.926,p<0.0001), and ≥S2 steatosis (0.860;95%CI0.788-0.932,p<0.0001). CAP performed similarly in patients with CAP-IQR≥ or <40 dB/m. CONCLUSIONS Steatosis is frequent in patients with cACLD and metabolic syndrome. CAP diagnostic accuracy for any steatosis and high-grade steatosis is good in this population. A CAP-IQR ≥40 dB/m does not impair CAP diagnostic accuracy in cACLD.