Doctor: Rym El Rafei
Title: Postnatal growth and neurodevelopmental outcomes of very preterm children in Europe
Supervisor: Jennifer Zeitlin
Doctoral school: ED 393 Epidemiology and Biomedical Information Sciences, Université Paris Cité
Date of thesis defense: 05/2022
Jury: Géraldine Gascoin-Lachambre
Very preterm (VPT) infants (<32 weeks of gestational age (GA)) face higher risks than term infants for neurodevelopmental problems, including impairment in cognitive and motor function. These infants are prone to extrauterine growth restriction (EUGR), which has been associated with neurodevelopmental impairment (NDI). As postnatal growth is a modifiable factor, reducing EUGR may be one way to improve these outcomes. This doctoral project aimed to describe EUGR prevalence, based on discharge weight, and to evaluate its association with NDI using data from the population-based Effective Perinatal Intensive Care in Europe (EPICE) cohort of VPT infants born in 2011-2012 in 11 countries and followed-up at 2 and 5 years of age. Among 6259 VPT infants surviving to discharge, EUGR prevalence, tested using four indicators, was high, with marked variation across countries (e.g. from 24% in Sweden to 60% in Portugal). We found that growth velocity measures were better suited to our European setting than percentile-based indicators. Our analysis of 4197 VPT infants at 2 years of corrected age, found that severe EUGR, defined using velocity indicators, was associated with increased risk for NDI, but only among boys. At age 5, among 763 infants born < 28 weeks’ GA, severe EUGR was associated with a 3 to 5 point IQ deficit, which was of similar magnitude for boys and girls. These results add to evidence about the association between EUGR and NDI. They also suggest that poor postnatal growth may be a marker of risk for infants who could benefit from reinforced follow-up. Outstanding questions concern the underlying roles of optimal nutritional strategies and neonatal morbidities.