Neurodevelopmental Outcomes of Infants at <29 Weeks of Gestation Born in Canada Between 2009 and 2016

OBJECTIVE: To evaluate changes in mortality or significant neurodevelopmental impairment (NDI) in children born at <29 weeks of gestation in association with national quality improvement initiatives. STUDY DESIGN: This longitudinal cohort study included children born at 22^0/7 to 28^6/7 weeks of gestation who were admitted to Canadian neonatal intensive care units between 2009 and 2016. The primary outcome was a composite rate of death or significant NDI (Bayley Scales of Infant and Toddler Development, Third Edition score <70, severe cerebral palsy, blindness, or deafness requiring amplification) at 18-24 months corrected age. To evaluate temporal changes, outcomes were compared between epoch 1 (2009-2012) and epoch 2 (2013-2016). aORs were calculated for differences between the 2 epochs accounting for differences in patient characteristics. RESULTS: The 4426 children included 1895 (43%) born in epoch 1 and 2531 (57%) born in epoch 2. Compared with epoch 1, in epoch 2 more mothers received magnesium sulfate (56% vs 28%), antibiotics (69% vs 65%), and delayed cord clamping (37% vs 31%) and fewer infants had a Score for Neonatal Acute Physiology, version II >20 (31% vs 35%) and late-onset sepsis (23% vs 27%). Death or significant NDI occurred in 30% of children in epoch 2 versus 32% of children in epoch 1 (aOR, 0.86; 95% CI, 0.75-0.99). In epoch 2, there were reductions in the need for hearing aids or cochlear implants (1.4% vs 2.6%; aOR, 0.50; 95% CI, 0.31-0.82) and in blindness (0.6% vs.1.4%; aOR, 0.38; 95% CI, 0.18-0.80). CONCLUSIONS: Among preterm infants born at <29 weeks of gestation, composite rates of death or significant NDI and rates of visual and hearing impairment were significantly lower in 2013-2016 compared with 2009-2012.