Increased CKD Risk after Community-Acquired AKI

Patients with acute kidney injury (AKI) seen in the emergency department are at increased risk of chronic kidney disease (CKD) and death within 5 years, reports a study in Kidney International.

The prospective cohort study included 616 patients admitted to the emergency department of a Portuguese tertiary hospital and followed up for a median of 5 years. Of these, 130 met criteria for AKI. Another 159 had transient azotemia and 15 had stable CKD; the remaining 312 had normal kidney function. Risks of CKD and mortality associated with community-acquired AKI were assessed, along with the added predictive value of plasma biomarkers measured in the emergency department.

With adjustment for clinical factors, patients with AKI were at significantly increased risk of stage 3 CKD, hazard ratio (HR) 5.7; and death, HR 1.9. In a model including biomarkers, serum cystatin C increased predictive ability for both markers: HR 1.5 for stage 3 CKD and 1.6 for death.

Plasma neutrophil gelatinase-associated lipocalin had no predictive value in addition to AKI. Patients with transient azotemia were also at increased risk of CKD: HR 2.4.

Critically ill hospitalized patients who survive an episode of AKI have a known increase in risk of progression to CKD. Less is known about the risk of CKD or death associated with community-acquired AKI, a less severe but more common condition.

The new study shows a fivefold increase in the risk of stage 3 CKD among patients with community-acquired AKI, compared to emergency department patients with normal renal function. The AKI patients also show a modest but significant increase in mortality risk. The researchers conclude: “Our findings highlight the importance of follow-up of patients with community-acquired acute kidney injury, for potential early initiation of renal protective strategies” [Soto K, et al. The risk of chronic kidney disease and mortality are increased after community-acquired acute kidney injury. Kidney Int 2016; 90:1090–1099].