Time to diagnosis of acute kidney injury and its predictors among outborn neonates in India: a competing-risk analysis of tele-ICU network data (2022–2024)

Abstract

Background There is limited data on neonatal acute kidney injury (AKI) from resource-constrained settings. In this study, we describe time to AKI diagnosis and its predictors among neonates born outside the treating hospital (outborn) in India, accounting for competing events like death and discharge against medical advice (DAMA). Methods This multicentre retrospective study leveraged data from a tele-NICU network across 27 sites in India from May 2022–June 2024. It included neonates 28 days or younger at admission with two or more serum creatinine values measured within a seven-day span, beginning after 48 h of life. AKI was determined using neonatal modified Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Primary outcome was time-to-AKI diagnosis. Cumulative incidence function was used to estimate AKI risk over time and Cox proportional hazards model was used to identify predictors amid competing events. Secondary outcomes like death, DAMA and length of hospitalisation were described. Findings Among 570 neonates, sex was recorded for 506; of these, 411 (81.2%) were male and 95 (18.8%) were female. The mean gestational age was 35.4 weeks (SD 3.1; range 24.3–42.7 weeks). Median post-natal age at admission was 2 days (IQR 1–5). AKI occurred in 170 (29.8%) neonates. Median time-to-AKI diagnosis was 2 days (IQR 1–5) post-admission; five-day cumulative incidence was 0.23 (95% CI: 0.20–0.27). Significant predictors of early AKI included dehydration (HR 3.63, 95% CI: 1.67–7.92), mechanical ventilation (HR 1.84, 95% CI: 1.32–2.56) and vasopressor use (HR 1.33, 95% CI: 1.05–1.69). AKI was associated with higher DAMA (34.7% vs. 25.2%, p=0.02) and Death (13.5% vs. 5.3%, p < 0.01). Interpretation Outborn neonates have rapid time-to-AKI diagnosis post-admission, highlighting a critical high-risk window for kidney-protective interventions. Policy changes to strengthen medical transport and referral systems may additionally reduce AKI risk among outborn neonates. Funding Fred Lovejoy Resident Research and Education Award (Boston Children's Hospital).