Neonatal Acute Kidney Injury and the Risk of Intraventricular Hemorrhage in the Very Low Birth Weight Infant

Abstract

Despite improvements in survival of premature infants, many have comorbid conditions. The role of the kidney in multiorgan dysfunction is unclear, particularly in regard to intraventricular hemorrhage (IVH). We hypothesized that infants diagnosed with acute kidney injury (AKI) have an increased risk of IVH independent of gestational age (GA) and other variables associated with both comorbidities. This prospective cohort study consisted of 125 infants with a birth weight ≤1,200 g and/or GA ≤31 weeks. A definition of AKI was used from KDIGO, not including urine output as nonoliguria is common in this population. IVH was based on serial head ultrasounds. Neonates with AKI had a higher trend towards having IVH compared to those without [14/35 (40%) vs. 22/83 (26.5%), p = 0.1]. Infants with AKI were more likely to have stage 2 IVH or higher than those without AKI [12/36 (33.3%) vs. 6/82 (7.3%); p < 0.01]. AKI was associated with a 3.6-fold increased risk of a grade 2 or higher IVH [hazard ratio (HR) 3.55, 95% confidence interval (CI) 1.39-9.07] and over 4-fold increase in risk of a grade 3 or higher IVH (HR 4.34, 95% CI 1.43-13.21). While there was no association between AKI and IVH overall, those with AKI had a higher hazard ratio to develop a grade 2 or higher IVH even when controlling for birth weight, antenatal steroid use, and 5-min Apgar score. Future studies are indicated to expand sample size and to control for other clinical variables that could be associated with both AKI and IVH.