Neurological outcome at 6 and 12 months corrected age in hospitalised late preterm infants -a prospective study.

Abstract

Late preterm infants (34-0/7 to 36-6/7 weeks" gestation) account for 10-20% of NICU admissions and are at increased risk for morbidity and mortality. Although they are prone to developmental delays, reports on neurological outcome during the first 2 years of life are scarce. The aim of the study was to assess neurological/neuromotor outcome in high risk late preterm infants at 6 and 12 months corrected age and the change in neurological scores over time, and to identify factors associated with the neurological outcome. The Hammersmith Infant Neurological Examination was performed in a cohort of 157 late preterm infants admitted in the NICU. The infants were examined at 6 and 12 months corrected age respectively and scored with the optimality score system including 26 items assessing cranial nerve function, posture, movements, tone and reflexes. Also parents reported neurological milestones in the follow up visit. Infants at 6 months had a global score of 59 (47-76) and optimal scores achieved in 25.4%. At 12 months they had a global score of 70 (58-78) and achieved optimal scores in 63.2%. The subscores of posture, tone and reflexes gradually increased from 6 to 12 months corrected age. Being born small for gestational age was the only factor that adversely influenced HINE score at 6 and 12 months. At 12 months 58.5% achieved independent walking. High risk late preterm infants have suboptimal HINE scores at 6 and 12 months of age, suggesting a need for closer follow up and early intervention programs.