Postnatal growth restriction and neurodevelopment at 5 years of age: a European extremely preterm birth cohort study

Objective To investigate whether extrauterine growth restriction (EUGR) during the neonatal hospitalisation by sex among extremely preterm (EPT) infants is associated with cerebral palsy (CP) and cognitive and motor abilities at 5 years of age. Study design Population-based cohort of births <28 weeks of gestation with data from obstetric and neonatal records and parental questionnaires and clinical assessments at 5 years of age. Setting 11 European countries. Patients 957 EPT infants born in 2011-2012. Main outcomes EUGR at discharge from the neonatal unit was defined as (1) the difference between Z-scores at birth and discharge with <-2 SD as severe, -2 to -1 SD as moderate using Fenton's growth charts (Fenton) and (2) average weight-gain velocity using Patel's formula in grams (g) per kilogram per day (Patel) with <11.2 g (first quartile) as severe, 11.2-12.5 g (median) as moderate. Five-year outcomes were: a CP diagnosis, intelligence quotient (IQ) using the Wechsler Preschool and Primary Scales of Intelligence tests and motor function using the Movement Assessment Battery for Children, second edition. Results 40.1% and 33.9% children were classified as having moderate and severe EUGR, respectively, by Fenton and 23.8% and 26.3% by Patel. Among children without CP, those with severe EUGR had lower IQ than children without EUGR (-3.9 points, 95% Confidence Interval (CI)=-7.2 to -0.6 for Fenton and -5.0 points, 95% CI=-8.2 to -1.8 for Patel), with no interaction by sex. No significant associations were observed between motor function and CP. Conclusions Severe EUGR among EPT infants was associated with decreased IQ at 5 years of age.