Community acquired versus Hospital acquired acute kidney injury at a large Australian metropolitan quaternary referral centre - incidence, associations, and outcomes.

Abstract

To determine incidence and outcomes of community-acquired (CA-AKI) and hospital-acquired acute kidney injury (HA-AKI) among inpatients in the Australian healthcare setting utilising modern health information systems. A retrospective cohort study of adult patients admitted to a quaternary hospital in Melbourne, Australia, between 1 January 2018 and 31 December 2019 utilising an electronic data warehouse. Adult patients admitted for >24 hours who had more than one serum creatinine level recorded during admission. Kidney transplant and maintenance dialysis patients were excluded. Acute kidney injury (AKI), as classified by the Kidney Disease Improving Global Outcomes (KDIGO) criteria, hospital length of stay (LoS), and 30-day mortality. 6477 AKI episodes were identified across 43,791 admissions. Of all AKI episodes, 77% (n=5011), 15% (n=947), and 8% (n=519) were KDIGO Stage 1, 2 and 3, respectively. HA-AKI accounted for 55.9% episodes. Patients required Intensive Care Unit admission in 22.7% (n=1100) of CA-AKI and 19.3% (n=935) of HA-AKI, compared to 7.5%. (n=2815) of patients with no AKI (p=0.001). Patients with AKI were older with more co-morbidities, particularly chronic kidney disease (CKD). LoS was longer in CA-AKI (8.8 days) and HA-AKI (11.8 days) compared to admissions without AKI (4.9 days, p<0.001). 30-day mortality was increased with CA-AKI (10.2%) and HA-AKI (12.8%) compared to no AKI (3.7%, p<0.001). The incidence of AKI detected by the electronic data warehouse was higher than previously reported. Patients who experienced AKI had greater morbidity and mortality. CKD was an important risk factor for AKI in hospitalised patients. This article is protected by copyright. All rights reserved.