Assistant Professor Eastern Virginia Medical School at Old Dominion University Norfolk, Virginia, United States
Objective: Studies addressing preterm birth often focus on immediate neonatal outcomes but there are limited data on their association with long-term outcomes. Our objective was to evaluate the relationship between neonatal morbidity measures and pulmonary and neurocognitive outcomes in children.
Study Design: Secondary analysis of a prospective follow-up study of children (median age 7 years) of mothers at high risk for late preterm birth who were randomized to corticosteroids versus placebo. Children with pulmonary and neurocognitive outcomes were included. Immediate neonatal resuscitation, defined as any intervention in the first 30 minutes other than blow-by oxygen, as well as the neonatal morbidity index (NMI) with and without NICU length of stay (LOS) were evaluated as exposures. The NMI is a validated composite score based on the number of specific events: respiratory distress syndrome, bronchopulmonary dysplasia, grade III/IV intraventricular hemorrhage, periventricular leukomalacia, proven sepsis, or necrotizing enterocolitis. The primary outcomes were: (1) pulmonary impairment (abnormal spirometry and/or asthma diagnosis with medication use), and (2) neurocognitive delay (DAS-II General Conceptual Ability score < 85). Associations were evaluated using relative risk (RR) and Cochran-Armitage trend tests, with a sensitivity analysis among children born preterm.
Results: Among 1,194 children with a median GA at delivery of 36 weeks, NMI ≥ 1 (see Table footnote) was not associated with long-term pulmonary or neurocognitive impairment. However, NMI incorporating NICU LOS was associated with neurocognitive impairment at the highest NMI score (3) and with progressively increasing risk of pulmonary impairment (Tables 1 & 2). Need for immediate neonatal resuscitation was not associated with neurocognitive impairment (Table 2). Sensitivity analysis of children born preterm showed similar findings.
Conclusion: TheNMI incorporating NICU LOS, but not NMI alone, is associated with long-term pulmonary, but not neurocognitive, impairment, supporting its potential as a surrogate predictor for pulmonary outcomes.
