To examine risk factors for mortality among preterm infants during newborn and subsequent hospitalizations, and whether they differ by race/ethnicity.
We conducted a cross-sectional analysis using the 2016 Kids Inpatient Database. Hospitalizations of preterm infants were categorized as “newborn” for birth admissions, and “post-newborn” for all others. Multivariate logistic regression was performed to calculate associations of mortality with sociodemographic factors.
Of 285915 hospitalizations, there were 7827 (2.7%) deaths. During newborn hospitalizations, adjusted OR (aOR) of death equaled 1.14 (95% CI 1.09–1.20) for males, 68.73 (61.91–76.30) for <29 weeks GA, and 0.81 (0.71–0.92) for transfer. Stratified by race/ethnicity, aOR was 0.69 (0.61–0.71) for Medicaid only among black infants. During post-newborn hospitalizations, death was associated with transfer (aOR 5.02, 3.31–7.61).
Risk factors for death differ by hospitalization types and race/ethnicity. Analysis by hospitalization types may identify risk factors that inform public health interventions for reducing infant mortality.
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Datasets utilized in the paper are publicly available through the Agency for Healthcare Research and Quality at https://www.hcup-us.ahrq.gov/kidoverview.jsp
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Matoba, N., Kwon, S., Collins, J.W. et al. Risk factors for death during newborn and post-newborn hospitalizations among preterm infants. J Perinatol 42, 1288–1293 (2022). https://doi.org/10.1038/s41372-022-01363-z