Survival and predictors of neonatal mortality: a hospital-based retrospective follow-up study from Addis Ababa, Ethiopia.

Background: Neonatal mortality remains one of the most pressing global health challenges, disproportionately affecting low- and middle-income countries. In Ethiopia, complex interrelated factors contribute to high neonatal mortality rates, creating a multifaceted public health concern that demands comprehensive investigation. Despite the magnitude of this challenge, there exists a notable lack of longitudinal studies that examine the temporal patterns of neonatal deaths, survival, and associated risk factors throughout the complete neonatal period. This study addresses this gap by evaluating survival outcomes and identifying determinants of mortality among neonates admitted to the neonatal intensive care unit at Zewditu Memorial Hospital, a referral facility serving a high-burden urban population in Addis Ababa, Ethiopia. Methods: A retrospective cohort study of 1,014 neonates admitted to the neonatal intensive care unit from September 11, 2020 to September 10, 2023 was conducted. Systematic random sampling was used to select patients. An electronic data collection method was used, and the data were exported to STATA version 17.0 for cleaning and analysis. Bi-variable and multivariable Cox proportional hazard regression models were employed to identify mortality risk predictors. Kaplan-Meier survival estimates and log-rank tests were used to compare survival probabilities. Model adequacy was assessed using the Cox-Snell residual test. Results: Over 7,945 neonate-days, the mortality incidence rate was 13.72 deaths per 1,000 neonate-days (95% confidence interval (CI) [11.37-16.55]), with most deaths occurring within the first week. Significant predictors of mortality risk were extremely low birth-weight (<1,000 g; Adjusted Hazard Ratio (AHR) = 18.94, 95% CI [7.89-45.23]), very low birth weight (1,000-1,499 g; AHR = 5.09, 95% CI [2.75-9.43]), perinatal asphyxia (AHR = 3.52, 95% CI [2.25-5.49]), neonatal sepsis (AHR = 2.47, 95% CI [1.28-4.77]), respiratory distress syndrome (AHR = 1.65, 95% CI [1.01-2.68]), and meconium aspiration syndrome (AHR = 2.35, 95% CI [1.20-4.57]). Conclusion: This study found associations between elevated neonatal mortality rates and birth weight and specific perinatal complications as key factors linked to survival. The predominance of deaths within the first week, particularly among neonates with low birth weight, perinatal asphyxia, sepsis, respiratory distress syndrome, and meconium aspiration syndrome, necessitates the implementation of risk-stratified care and intensive early monitoring. These findings provide evidence for targeted interventions that could substantially reduce neonatal mortality in resource-constrained healthcare settings.