Neurodevelopmental outcome at 5.5 years in Dutch preterm infants born at 24–26 weeks’ gestational age: the EPI-DAF study

Objective After lowering the Dutch threshold for active treatment from 25 to 24 completed weeks’ gestation, survival to discharge increased by 10% in extremely preterm live born infants. Now that this guideline has been implemented, an accurate description of neurodevelopmental outcome at school age is needed. Design Population-based cohort study. Setting All neonatal intensive care units in the Netherlands. Patients All infants born between 240/7 and 266/7 weeks’ gestation who were 5.5 years’ corrected age (CA) in 2018–2020 were included. Main outcome measures Main outcome measure was neurodevelopmental outcome at 5.5 years. Neurodevelopmental outcome was a composite outcome defined as none, mild or moderate-to-severe impairment (further defined as neurodevelopmental impairment (NDI)), using corrected cognitive score (Wechsler Preschool and Primary Scale of Intelligence Scale-III-NL), neurological examination and neurosensory function. Additionally, motor score (Movement Assessment Battery for Children-2-NL) was assessed. All assessments were done as part of the nationwide, standardised follow-up programme. Results In the 3-year period, a total of 632 infants survived to 5.5 years’ CA. Data were available for 484 infants (77%). At 5.5 years’ CA, most cognitive and motor (sub)scales were significantly lower compared with the normative mean. Overall, 46% had no impairment, 36% had mild impairment and 18% had NDI. NDI-free survival was 30%, 49% and 67% in live born children at 24, 25 and 26 weeks’ gestation, respectively (p<0.001). Conclusions After lowering the threshold for supporting active treatment from 25 to 24 completed weeks’ gestation, a considerable proportion of the surviving extremely preterm children did not have any impairment at 5.5 years’ CA. All data relevant to the study are included in the article or uploaded as supplementary information. Other data may be obtained from a third party and are not publicly available.