Longer time to resolve means greater risk of major adverse kidney events

The timing of functional recovery from acute kidney injury is associated with the risk of future adverse events, researchers found.

Pavan K. Bhatraju, MD, MSc, Department of Medicine, University of Washington, Seattle, and colleagues, found that patients who had non-resolving acute kidney injury (AKI) within the first 72 hours after diagnosis had more than a 50% greater risk of major adverse kidney events compared to patients with resolving AKI.

The study was published in JAMA Network Open.

AKI is defined, per the Kidney Disease: Improving Global Outcomes (KDIGO) consensus group, as an increase in the concentration of serum creatinine of 0.3 mg/dL or more, or 50% or more of the baseline within a 48-hour period or within 7 days after hospitalization, or a decrease in urine output.

However, Bhatraju and colleagues pointed out that this definition doesn’t stratify patients based on the differences of their recovery patterns, and that the trajectory of renal dysfunction “is a potentially important and clinically intuitive parameter by which to risk stratify AKI.”

Here the researchers wanted to determine whether that trajectory within 72 hours after the onset of AKI is associated with major adverse kidney events (MAKE), such as chronic kidney disease, dialysis, and death.

In this prospective multicenter cohort study, Bhatraju and colleagues enrolled 1,538 adults (964 men; mean [SD] age, 64.6 [12.7] years) with or without AKI 3 months after hospital discharge.

Those participants with AKI were classified as having resolving AKI (defined as a decrease in serum creatinine concentration of 0.3 mg/dL or more or 25% or more from maximum in the first 72 hours after AKI diagnosis) or non-resolving AKI.

Half of the 1,538 study participants had no AKI, while 475 (31%) had resolving AKI, and 294 (19%) had non-resolving AKI.

Participants with non-resolving AKI were more likely than those with resolving AKI to be men, have diabetes, and have preexisting chronic kidney disease. Participants with resolving AKI were more likely than those with non-resolving AKI to have sepsis, and KDIGO stages 2 and 3. Of the 769 patients with AKI, 74% had KDIGO stage 1 AKI.

MAKE occurred in 36% (550) of the 1,538 participants in the study. The incidence rate of MAKE was 5.9 events per 100 patient-years among participants without AKI, 11.9 events per 100 patient-years among those with resolving AKI, and 16.6 events per 100 patient-years among those with non-resolving AKI. Bhatraju and colleagues determined that the adjusted hazard ratio for MAKE was higher for both patients with resolving AKI (adjusted hazard ratio, 1.52; 95% CI, 1.01-2.29, and for those with non-resolving AKI (adjusted hazard ratio 2.30; 95% CI, 1.52-3.48), compared with participants without AKI.

Patients with non-resolving AKI had a 51% greater risk of MAKE (95% CI, 22%-88%) compared to those with resolving AKI.

Bhatraju and colleagues suggested the results of their study have two major implications. First, their findings appear to be generalizable to most hospitalized patients with AKI. Second, they noted that identifying patients with non-resolving AKI could “facilitate prognostic enrichment” of AKI clinical trials, as well as help target resources for the follow-up and early detection of chronic kidney disease in patients with AKI.

In a commentary accompanying the study, Ravindra L. Mehta, MBBS, MD, DM, University of California, San Diego, wrote that in trying to understand the connection between the timing of AKI recovery and adverse outcomes, “it is important to realize that these are just initial pieces of the puzzle.”

For example, she pointed out that varying definitions of what kidney recovery actually entails results in widely disparate recovery rates, suggesting that a uniform definition is necessary.

Evidence suggests more research in this area is needed, she wrote. “It is, however, clear that clinicians managing patients with AKI should consider the severity of the disease and the ensuing course and tailor their diagnostic and therapeutic interventions to facilitate rapid and complete recovery of kidney function.

“Ultimately, restoring good health is the goal for which both patients and physicians are striving.”

  1. The amount of time it takes to recover kidney function after acute kidney injury is associated with long-term clinical outcomes.

  2. Patients with longer recovery times had a significantly greater risk of long-term major adverse kidney events, such as chronic kidney disease, dialysis, and death, than patients with early recovery.

Michael Bassett, Contributing Writer, BreakingMED™

Bhatraju reports no disclosures.

Mehta reports no disclosures.

Cat ID: 127

Topic ID: 81,127,730,127,192,925