Long-term outcomes of community-acquired versus hospital-acquired acute kidney injury: a retrospective analysis

Aim: To compare long-term outcomes in CA-AKI to HA-AKI. The hypothesis was that renal and patient survival would be better in CA-AKI than in HA-AKI. Methods: Retrospective cohort analysis of patients hospitalized from 2004 to 2005, in Upstate New York Veterans Affairs hospitals. The groups: CA-AKI (n = 560), HA-AKI (n = 158), or No AKI (NA) (n = 2,320). Risk, injury, failure, loss, and end-stage kidney (RIFLE) criterion was used to define AKI. Primary outcomes: doubling of serum creatinine, end-stage renal disease (ESRD), death, and a composite of the three. Secondary outcomes: de novo chronic kidney disease (CKD), recovery of renal function, and re-admission rate. The cumulative incidence of outcomes was determined over a period of 3 years after discharge. Results: CA-AKI was 3.5 times as prevalent as HA-AKI. In comparison to patients with HA-AKI, those with CA-AKI had better estimated glomerular filtration rate (71.3 vs. 61.1 mL/min/1.73 m(2), p < 0.001) and lower prevalence of CKD (42.3 vs. 51.9%, p = 0.03) at baseline. More patients with CA-AKI than HA-AKI met RIFLE failure criterion (43.8 vs. 29.1%, p < 0.001). By 3 years, no differences were found for the individual primary and secondary outcomes tested (all p > 0.05). Conclusions: CA-AKI was found to be considerably more common than HA-AKI and had similar long-term consequences.