Low Apgar Score and the Risk of Neonatal Acute Kidney Injury: Evidence from a Matched Retrospective Cohort Study

Background: The Apgar score is a widely used indicator for assessing newborn health immediately after birth. However, its predictive value for specific organ dysfunctions such as acute kidney injury (AKI) remains uncertain. This study aimed to evaluate the association between low ۵-minute Apgar scores and the risk of AKI in neonates admitted to the neonatal intensive care unit (NICU). Methods: In this retrospective matched cohort study conducted between ۲۰۲۲ and ۲۰۲۴ at Amir Al-Momenin Hospital, ۸۰ neonates (۴۰ with Apgar <۷ and ۴۰ with Apgar ≥۷) were enrolled. Neonates were matched ۱:۱ for gestational age and admission time. Serum creatinine was measured on days ۱, ۳, ۵, and ۷, and urine output was assessed on day ۳ to diagnose AKI based on modified neonatal KDIGO criteria. Statistical analyses included the Chi-square test for categorical variables, Mann–Whitney U test for non-normally distributed continuous variables, and logistic regression analysis. Results: Low ۵-minute Apgar scores were associated with a significantly higher incidence of AKI (۲۰% vs. ۵%, P = ۰.۰۴۳), with a ۶.۳-fold increased risk (OR = ۶.۲۹, ۹۵% CI: ۱.۰۴–۳۷.۹۰, P = ۰.۰۴۵). Gestational age between ۲۸–۳۲ weeks independently increased the risk of AKI (OR = ۱۳.۸۴, P = ۰.۰۲۷). Although day ۱ serum creatinine was higher in the normal Apgar group (P = ۰.۰۰۲), no differences were observed afterward. Male sex and vaginal delivery were more common in the low Apgar group but were not associated with AKI in multivariable analysis. Conclusion: A ۵-minute Apgar score <۷ and gestational age between ۲۸–۳۲ weeks are significant risk factors for AKI in NICU neonates. These findings highlight the potential of using Apgar score and gestational age for early risk stratification and targeted monitoring.

کلیدواژه ها:

Acute kidney injury ، Apgar score ، Neonatal Intensive Care Unit ، Neonates ، Renal function