Outcomes of Community-Acquired Acute Kidney Injury: A Cohort Study of US Veterans.

BACKGROUND: Community-acquired acute kidney injury (CA-AKI) occurs outside of the hospital and is the most common form of AKI. CA-AKI is not well understood, which hinders efforts to prevent, identify, and manage CA-AKI. OBJECTIVE: Examine 30-day outcomes following CA-AKI using national administrative and lab data from the Veterans Health Administration (VA). RESEARCH DESIGN: Retrospective cohort study. SUBJECTS: VA primary care patients with recorded outpatient serum creatinine (SCr) with observed CA-AKI (cases) and a standardized mortality ratio propensity-weighted 5% comparator sample without observed CA-AKI in 2013-2017. MEASURES: CA-AKI was defined as a ≥1.5-fold relative increase in outpatient SCr or inpatient SCr (≤24 h from admission) from a reference outpatient SCr ≤12 months prior. Outcomes were 30-day mortality and hospitalization and were assessed in separate weighted Cox regression models. RESULTS: Among 220,777 CA-AKI events and 492,539 comparators without observed CA-AKI, CA-AKI was associated with a higher risk of 30-day all-cause mortality [hazard ratio (HR)=4.17, 95% CI: 3.74, 4.63] and hospitalization (HR=1.82, 95% CI: 1.74, 1.90) versus comparator. Risks increased with severity (mortality HR=3.02, 7.67, and 12.22 for AKI stages 1-3, respectively). Outpatient CA-AKI was associated with a high risk of mortality (HR=2.04, 95% CI: 1.83, 2.28) and even higher for inpatient CA-AKI, present [≤24 h from admission (HR=11.32, 95% CI: 10.16, 12.61)]. CONCLUSIONS: In a national cohort of Veterans, CA-AKI was associated with a 2-fold increased risk of hospitalization and a 3-11-fold risk of mortality. Improving identification and management is critical to mitigate adverse outcomes of CA-AKI.

Duke Scholars

Author Virginia Wang Population Health Sciences

Author Valerie A. Smith Population Health Sciences

Author Christopher Barrett Bowling Medicine, Geriatrics and Palliative Care

Author Matthew Leonard Maciejewski Population Health Sciences

Author Clarissa Jonas Diamantidis Medicine, General Internal Medicine