Recovery From Dialysis-Treated Acute Kidney Injury in Patients With Cirrhosis: A Population-Based Study

Abstract

Rationale & objective: The decision to initiate kidney replacement therapy (KRT) for acute kidney injury (AKI) in cirrhosis remains controversial because it is unclear which patients will benefit. We sought to characterize factors associated with recovery from KRT-treated AKI in patients with cirrhosis to inform shared clinical decision-making.

Study design: Population-based retrospective cohort study.

Setting & participants: Adult patients from Ontario, Canada, identified using administrative data to have cirrhosis at the time of hospital admission with AKI (based on serum creatinine level) who were treated with KRT (January 1, 2009, to December 31, 2016) and followed up until the end of 2017.

Exposures: Demographic characteristics and comorbidities before admission.

Outcomes: Kidney recovery defined as the absence of KRT for at least 30 days.

Analytical approach: The cumulative incidences of kidney recovery, death, and liver transplant were calculated at 1, 3, 6, and 12 months, and independent predictors of kidney recovery were evaluated using Fine and Gray competing risk regression models that generated subdistribution hazards ratios (sHRs).

Results: Overall, 722 patients were included (median age, 61 [interquartile range, 54-68] years; Model for End-Stage Liver Disease (MELD)-Na score, 26 [interquartile range, 22-34]; 66% were male; 52% had viral hepatitis, 25% nonalcoholic fatty liver disease, 18% alcohol-associated liver disease). The cumulative incidences of kidney recovery at 1, 3, 6, and 12 months were 3%, 22%, 25%, and 26%, respectively. Higher MELD-Na score (sHR per 5 units greater, 0.72 [95% CI, 0.65-0.80]), acute-on-chronic liver failure (sHR, 0.61 [95% CI, 0.43-0.86]), and sepsis (sHR, 0.57 [95% CI, 0.41-0.81]) were associated with a lower hazard of kidney recovery, whereas those on a liver transplant waitlist (sHR, 3.10 [95% CI, 1.96-4.88]) and who were admitted to a teaching hospital (sHR, 1.48 [95% CI, 1.05-2.08]) were more likely to experience kidney recovery.

Limitations: Observational design, AKI etiology not identified.

Conclusions: Kidney recovery from KRT occurred in only one quarter of patients and was very unlikely after 3 months. These findings provide information regarding prognosis that may guide decisions regarding KRT initiation and continuation.

Keywords: Acute kidney injury (AKI); ICES; cirrhosis; competing risk; dialysis; dialysis initiation; kidney function; kidney recovery; liver transplant; mortality; renal prognosis; renal replacement therapy (RRT); routinely collected health care data.