School-age neurodevelopmental outcomes after non-emergency red blood cell transfusions in preterm infants: a propensity score-matched study from the Epipage 2 cohort.

The objective of this study is to evaluate whether non-emergency red blood cell transfusions (RBCT) is associated with neurologic outcomes in preterm infants born at 27-31 weeks of gestation. This analysis used data from the Etude Epidémiologique sur les Petits Ages Gestationnels (EPIPAGE-2), a French nationwide prospective cohort. Infants born at 27-31 weeks and surviving to 5½ years were included, excluding those with emergency RBCT indications. Neurologic outcomes, defined as moderate or severe disabilities, a composite of motor, neurosensory, and cognitive disabilities, were assessed at 5½ years with standardized scales. Behavioral difficulties were evaluated using parental questionnaires. Transfused and non-transfused infants were matched 1:1 using propensity scores. Statistical analyses included odds ratios (ORs) and mean differences. Of the 2182 infants included (656 transfused, 1526 non-transfused), 1062 were matched (531 per group). In the unmatched cohort, RBCT exposure was significantly associated with the composite outcome of moderate to severe neurological disabilities (OR, 1.40; 95%CI, 1.04-1.87). Cognitive impairment and developmental coordination disorders were significantly increased with RBCT (OR, 1.40; 95%CI, 1.07-1.81 and OR, 1.44; 95%CI, 1.06-1.96), respectively. After adjustment using the propensity score, RBCTs were not significantly associated with any individual outcome: cerebral palsy, overall cognitive deficiency, coordination disorders, behavioral difficulties, or moderate-to-severe neurological disabilities. Only the association with cognitive performance relating to working memory persisted (mean difference, - 2.3; 95%CI, - 4.2 to - 0.5).

conclusionAfter controlling for potential confounders, non-emergency RBCTs in preterm infants born at 27-31 weeks were not significantly associated with long-term neurologic outcomes but reduced working memory warrants further investigation.

trial registrationNCT03078439. WHAT IS KNOWN: • Red blood cell transfusions (RBCTs) are frequently administered to preterm infants and have been associated with adverse neonatal outcomes in observational studies. • The long-term neurodevelopmental consequences of RBCT exposure remain uncertain because transfused infants are generally sicker and more immature, making confounding difficult to address. WHAT IS NEW: • In a large nationwide cohort of preterm infants born at 27-31 weeks' gestation, non-emergency RBCT exposure was associated with poorer neurodevelopmental outcomes in unadjusted analyses but not after propensity score matching.A modest reduction in working memory performance persisted after adjustment, suggesting a potential domain-specific effect that warrants further investigation.