Long-Term Kidney Outcomes Following Dialysis-Treated Childhood Acute Kidney Injury: A Population-Based Cohort Study

Significance Statement AKI is common among hospitalized neonates and children and associated with adverse short- and long-term kidney outcomes. However, data for long-term outcomes of children with episodes of dialysis-treated AKI are limited. Using Ontario provincial health administrative databases, the authors identified 1688 pediatric survivors hospitalized and treated with dialysis for AKI episodes in 1996–2017, and followed them for a median of 9.6 years. Compared with matched hospitalized comparators, AKI survivors were at significantly increased risk of long-term kidney failure or death. The authors also observed significantly higher long-term rates of CKD and hypertension among the dialysis-treated AKI survivors. These findings support enhanced surveillance of kidney function and blood pressure after episodes of severe childhood AKI, with the aim of improving long-term kidney and patient survival. Background AKI is common during pediatric hospitalizations and associated with adverse short-term outcomes. However, long-term outcomes among survivors of pediatric AKI who received dialysis remain uncertain. Methods To determine the long-term risk of kidney failure (defined as receipt of chronic dialysis or kidney transplant) or death over a 22-year period for pediatric survivors of dialysis-treated AKI, we used province-wide health administrative databases to perform a retrospective cohort study of all neonates and children (aged 0–18 years) hospitalized in Ontario, Canada, from April 1, 1996, to March 31, 2017, who survived a dialysis-treated AKI episode. Each AKI survivor was matched to four hospitalized pediatric comparators without dialysis-treated AKI, on the basis of age, sex, and admission year. We reported the incidence of each outcome and performed Cox proportional hazards regression analyses, adjusting for relevant covariates. Results We identified 1688 pediatric dialysis–treated AKI survivors (median age 5 years) and 6752 matched comparators. Among AKI survivors, 53.7% underwent mechanical ventilation and 33.6% had cardiac surgery. During a median 9.6-year follow-up, AKI survivors were at significantly increased risk of a composite outcome of kidney failure or death versus comparators. Death occurred in 113 (6.7%) AKI survivors, 44 (2.6%) developed kidney failure, 174 (12.1%) developed hypertension, 213 (13.1%) developed CKD, and 237 (14.0%) had subsequent AKI. AKI survivors had significantly higher risks of developing CKD and hypertension versus comparators. Risks were greatest in the first year after discharge and gradually decreased over time. Conclusions Survivors of pediatric dialysis–treated AKI are at higher long-term risks of kidney failure, death, CKD, and hypertension, compared with a matched hospitalized cohort.