Volume of Neonatal Care and Survival without Disability at 2 Years in Very Preterm Infants: Results of a French National Cohort Study

Abstract

To investigate the relation between neonatal intensive care unit (NICU) volume and survival, and neuromotor and sensory disabilities at 2years in very preterm infants. The EPIPAGE-2 (Etude Epidémiologique sur les Petits Âges Gestationnels-2) national prospective population-based cohort study was used to include 2447 babies born alive in 66 level III hospitals between 24 and 30 completed weeks of gestation in 2011. The outcome was survival without disabilities (levels 2-5 of the Gross Motor Function Classification System for cerebral palsy with or without unilateral or bilateral blindness or deafness). Units were grouped in quartiles according to volume, defined as the annual admissions of very preterm babies. Multivariate logistic regression analyses with population average models were used. Survival at discharge was lower in hospitals with lower volumes of neonatal activity (aOR 0.55, 95% CI 0.33-0.91). Survival without neuromotor and sensory disabilities at 2years increased with hospital volume, from 75% to 80.7% in the highest volume units. After adjustment for gestational age, small for gestational age, sex, maternal age, infertility treatment, multiple pregnancy, principal cause of prematurity, parental socioeconomic status, and mother's country of birth, survival without neuromotor or sensory disabilities was significantly lower in hospitals with a lower volume of neonatal activity (aOR 0.60, 95% CI 0.38-0.95) than in the highest quartile hospitals. These results suggest that lower neonatal intensive care unit volume is associated with lower survival without an increase in disabilities at 2years. These results could be useful to generate improvements of perinatal regionalization.