NASHVILLE, TN—While future chronic kidney disease is linked to the extent of recovery of kidney function following acute kidney injury, how the timing of recovery affects the rate of future loss of kidney function is not as well understood.
In response, a retrospective cohort study in the American Journal of Kidney Diseases examined the independent association between the timing of recovery from moderate to severe AKI and future loss of kidney function.
VA Tennessee Valley Health System researchers focused on 47,903 veterans with Stage 2 or 3 AKI who recovered to within 120% of baseline creatinine level within 90 days of peak injury. They grouped the timing of recovery of kidney function from peak inpatient serum creatinine level into 1-4, 5-10, 11-30 and 31-90 days.
The study team was looking for a sustained 40% decline in estimated glomerular filtration rate below that calculated from the last serum creatinine level available during the 90-day recovery period or kidney failure (2 outpatient estimated glomerular filtration rates<15mL/min/1.73m2, dialysis procedures > 90 days apart, kidney transplantation or registry within the U.S. Renal Data System).
Results indicated that, among 47,903 patients, 29,316 (61%), 10,360 (22%), 4,520 (9%) and 3,707 (8%) recovered within 1-4, 5-10, 11-30 and 31-90 days, respectively.
Researchers reported that, with a median follow-up of 42 months, unadjusted incidence rates for the kidney outcome were 2.01, 3.55, 3.86 and 3.68 events/100 person-years, respectively. Compared with 1-4 days, recovery within 5-10, 11-30 and 31-90 days was associated with increased rates of the primary outcome: adjusted HRs were 1.33 (95% CI, 1.24-1.43), 1.41 (95% CI, 1.28-1.54) and 1.58 (95% CI, 1.43-1.75), respectively, the study noted.
The authors said the results were limited by the predominantly male population, residual confounding and inability to make causal inferences because of the retrospective observational study design. They added, “The timing of recovery provides an added dimension to AKI phenotyping and prognostic information regarding the future occurrence of loss of kidney function. Studies to identify effective interventions on the timing of recovery from AKI are warranted.”
1. Siew ED, Abdel-Kader K, Perkins AM, Greevy RA Jr, et. Al. Timing of RecoveryFrom Moderate to Severe AKI and the Risk for Future Loss of Kidney Function. Am JKidney Dis. 2019 Sep 16. pii: S0272-6386(19)30854-6. doi:10.1053/j.ajkd.2019.05.031. [Epub ahead of print] PubMed PMID: 31537394.