Incidence, risk factors, and outcomes of acute liver injury in hospitalized adults with acute kidney injury: a large multicenter study

Abstract

Background: Acute kidney injury (AKI) and acute liver injury (ALI) were associated with poor outcomes during hospitalization, respectively. However, the clinical outcome of AKI combined with ALI (AKI-ALI) remains unknown. The current study aimed to describe AKI-ALI's incidences, risk factors, and outcomes.

Methods: The study population included patients aged 18-99 years with enough serum creatinine and liver testing hospitalized at 19 medical centers throughout China between 2000 and 2021. AKI was defined by Kidney Disease Improving Global Outcomes and ALI was defined by the change of liver enzymes based on Asia Pacific Association of Study of Liver consensus guidelines. Cox proportional hazard model was used to identify risk factors for AKI-ALI, and a time-dependent Cox proportional hazard regression model was used to estimate the association between AKI-ALI and in-hospital mortality.

Results: Among the 18,461 patients with AKI, 1689 (9.1%) combined with ALI. Male patients or those who have used nonsteroidal anti-inflammatory drugs or vasopressors, and who have heart failure or shock, with higher AST or GGT values, were associated with an increased risk of AKI-ALI. Compared with AKI-nonALI, patients with AKI-ALI were at higher risk of in-hospitalized mortality (hazard ratio [HR] 1.76, 95% confidence interval [CI] 1.54, 2.00). In addition, a stronger association between AKI-ALI and in-hospital mortality was found in those with lower AKI grades (p for interaction = 0.037).

Conclusions: ALI was not uncommon among patients with AKI, especially in patients who used vasopressors and had shock. This study highlights the association between AKI-ALI and a significantly increased risk of mortality. It suggests that dynamic monitoring of liver function is essential, particularly in patients with AST and GGT exceeding the normal upper limit, to improve the in-hospital prognosis of AKI patients.

Keywords: Acute kidney injury; Acute liver injury; Cox regression; Epidemiology; Hospitalization; Ischemia injury; Mortality; Multicenter; Prognosis; Risk factors.