Global epidemiology of acute kidney injury in hospitalised patients with decompensated cirrhosis: the International Club of Ascites GLOBAL AKI prospective, multicentre, cohort study.

Background: Acute kidney injury (AKI) is a serious complication of cirrhosis. A systematic, global characterisation of AKI occurring in patients with cirrhosis is lacking. We therefore aimed to assess global differences in the characteristics, management, and outcomes of AKI in hospitalised patients with cirrhosis.

Methods: In this prospective, multicentre, cohort study, we enrolled adults (≥18 years) with decompensated cirrhosis who were hospitalised for a cirrhosis-related complication, with or without AKI, at 65 centres across five continents. We captured AKI prevalence, stage, phenotype, and details on AKI management and clinical course. Universal health coverage index and gross national income per capita were also collected. The primary outcome was 28-day mortality. Multivariable models including demographic and clinical variables, cirrhosis cause, cirrhosis severity, AKI severity, AKI management variables, universal health coverage, and gross national income were used to analyse independent associations with 28-day mortality. Secondary outcomes were AKI classification, progression, and resolution. This study is complete and registered with ClinicalTrials.gov (NCT05387811).

Findings: Between July 1, 2022, and May 31, 2023, we enrolled 3821 patients who were hospitalised for decompensated cirrhosis. Mean age was 57·7 years (SD 13·1), 2467 (64·6%) were men, and 1354 (35·4%) were women. Most patients were White (2128 [55·7%]). 1456 (38·1%, 95% CI 36·6-39·6) of 3821 patients had AKI (943 [64·8%] men and 513 [35·2%] women). Globally, patients presented with similar AKI stages, but patients from North America and Asia had the highest MELD-Na scores at presentation and the highest rates of peak AKI stage 3. Overall, hypovolaemic AKI was the most common phenotype (858 [58·9%] of 1456), followed by HRS-AKI (253 [17·4%]) and acute tubular necrosis (216 [14·8%]). The prevalences of hypovolaemic AKI and HRS-AKI were similar across regions, but acute tubular necrosis was more frequent in Asia (p<0·0001 across regions). Additionally, regional differences in the management of AKI (use of albumin, vasopressors, and diuretics) were found. 335 (28·6%) of 1171 patients with initial AKI stages 1 or 2 had progression to higher stages during hospitalisation. AKI resolved in 862 (59·2%) cases during hospitalisation. 333 (22·9%) patients with AKI had died by 28 days. Multivariable analyses showed that increased age, female sex, presence of ascites, presence of hepatic encephalopathy, increased white blood cell count, increased MELD-Na, hospital-acquired AKI, a lower universal health coverage index (<80), and not being in a high-income country were independently associated with an increased risk of 28-day mortality. Increased serum albumin was associated with a decreased risk of 28-day mortality.

Interpretation: This study found important regional differences in AKI severity, phenotype, management, and outcomes in patients with decompensated cirrhosis. Health-care coverage remains an important driver of survival in patients with cirrhosis and AKI.

Funding: European Association Study for the Study of the Liver and the Italian Society of Internal Medicine.