BACKGROUND There is a gap of knowledge in the long-term outcomes of patients who have complete recovery of kidney function after an episode of acute kidney injury (AKI). We sought to determine if complete recovery of kidney function after an episode of AKI is associated with development of incident stage 3 chronic kidney disease (CKD) and mortality in patients with normal baseline kidney function. DESIGN Retrospective cohort study. SETTING & PARTICIPANTS 3,809 patients from an integrated healthcare delivery system that had a hospitalization between January 1, 1999 and December 31, 2009 with follow-up through March 31, 2010. PREDICTOR AKI defined by ICD-9 codes and using the Acute Kidney Injury Network (AKIN) definition with complete recovery defined by reduction in serum creatinine to less than 1.10 times the baseline value. OUTCOMES AND MEASUREMENTS Incident stage 3 CKD persistent for 3 months and all-cause mortality. RESULTS After a median follow-up of 2.5 years, incident stage 3 CKD occurred in 15% and 3% of those with and without AKI, respectively, with an unadjusted HR of 5.93 (95% CI, 4.49-7.84) and a HR of 3.82 (95% CI, 2.81-5.19) in propensity score-stratified analyses. Deaths occurred in 35% and 24% of those with and without AKI, respectively, with an unadjusted HR of 1.46 (95% CI, 1.27-1.68). In the propensity score stratified analyses, HR decreased to 1.08 (95% CI, 0.93-1.27). LIMITATIONS Measurements of albuminuria were not available. CONCLUSIONS Complete recovery of kidney function after an episode of AKI in subjects with normal baseline kidney function is associated with an increased risk of development of incident stage 3 CKD but not all-cause mortality.

Lower kidney function is associated with incident asymptomatic PAD. In addition, the combination of impaired kidney function and incident PAD better predicts cardiovascular outcomes.