Epidemiology, characteristics, and outcomes of patients with acute‐on‐chronic liver failure in Australia.

Background and Aim: Acute‐on‐chronic liver failure (ACLF) is distinct from acute decompensation (AD) of cirrhosis in its clinical presentation, pathophysiology, and prognosis. There are limited published Australian ACLF data. Methods: We performed a single‐center retrospective cohort study of all adults with cirrhosis admitted with a decompensating event to a liver transplantation (LT) centre between 2015 and 2020. ACLF was defined using the European Association for the Study of the Liver‐Chronic Liver Failure (EASL‐CLIF) definition while those who did not meet the definition were classified as AD. The primary outcome of interest was 90‐day LT‐free survival. Results: A total of 615 patients had 1039 admissions for a decompensating event. On their index admission, 34% (209/615) of patients were classified as ACLF. Median admission model for end‐stage liver disease (MELD) and MELD‐Na scores were higher in ACLF patients compared with AD (21 vs 17 and 25 vs 20 respectively, both P < 0.001). Both the presence and severity of ACLF (grade ≥ 2) significantly predicted worse LT‐free survival compared with patients with AD. The EASL‐CLIF ACLF score (CLIF‐C ACLF), MELD and MELD‐Na scores performed similarly in predicting 90‐day mortality. Patients with index ACLF had a higher risk of 28‐day mortality (28.1% vs 5.1%, P < 0.001) and shorter times to readmission compared with those with AD. Conclusion: ACLF complicates over a third of hospital admissions for cirrhosis with decompensating events and is associated with a high short‐term mortality. The presence and grade of ACLF predicts 90‐day mortality and should be identified as those at greatest risk of poor outcome without intervention such as LT. [ABSTRACT FROM AUTHOR]