Kidney failure attributed to nonrecovery of acute kidney injury (AKI) may be more deadly over the short term than kidney failure resulting from diabetes mellitus and other causes, according to new study findings.
In an analysis of 1,045,540 patients with end-stage kidney disease (mean age 63 years) in the US Renal Data System (USRDS), 32,598 (3%) initiated maintenance dialysis due to AKI. Compared with kidney failure due to diabetes, kidney failure due to AKI was significantly associated with a 28% and 16% higher risk for all-cause mortality in the first 0–3 and 3-6 months in adjusted analyses, respectively, following dialysis initiation, Silvi Shah, MD, MS, of the University of Cincinnati Medical Center in Ohio, and colleagues reported in the Clinical Journal of the American Society of Nephrology. Kidney failure due to AKI was significantly associated with a 6% and 9% higher mortality risk, respectively, compared with kidney failure from causes other than diabetes.
Results showed that 35% of patients with kidney failure due to AKI eventually recovered their kidney function compared with just 4% and 7% of those with kidney failure due to diabetes and other causes, respectively. Further, 95% of these AKI patients recovered within 12 months, the team noted.
Women were 14% less likely to experience kidney recovery than men. The investigators suggested that women may have lower nephron mass, inferior anemia treatment, late dialysis initiation, and/or lower dialysis doses. In addition, black, Native American, Asian, and Hispanic patients were 32%, 28%, 18%, and 18% less likely than white patients to experience recovery, respectively, possibly due to late dialysis initiation.
Heart failure and age older than 80 years also were significantly associated with AKI nonrecovery.
“These observations strongly caution against implementing a ‘one-size-fits-all’ model of incident dialysis care and suggest the necessity of customized care for those with kidney failure due to AKI,” Dr Shah’s team wrote. They suggested reasons why AKI patients could be prone to early death, including illness severity and intolerance to standard dialysis. AKI patients may respond differently to ultrafiltration rates, may need better monitoring for intradialytic hypotension, or react differently to maintenance dialysis drugs, the authors noted.
In addition, patients with a history of predialysis nephrology care had a lower likelihood of kidney recovery than those who did not receive such care. The proportion of patients not receiving predialysis nephrology care was 73% in the group that experienced kidney recovery compared with 56% in the group that did not.
In a discussion of study limitations, the authors pointed out that their cohort included patients with kidney failure due to AKI, so their findings may not be generalizable to all patients with dialysis-requiring AKI. In addition, as USRDS data begin with incident dialysis information, “we were not able to ascertain the level of CKD prior to patients experiencing AKI. To that effect, the variable defining predialysis nephrology care may be considered a surrogate for receiving care for CKD prior to incident dialysis. This may explain our observation that predialysis nephrology care was associated with lower likelihood of kidney recovery.”
Shah S, Leonard AC, Harrison K, et al. Mortality and recovery associated with kidney failure due to acute kidney injury [published online June 17, 2020]. Clin J Am Soc Nephrol. doi: 10.2215/CJN.11200919