Cognitive development at late infancy and school age in children cooled for neonatal encephalopathy

We investigated the association and individual changes in cognitive scores between late infancy and early school age in children cooled for neonatal encephalopathy secondary to perinatal asphyxia (NE) who did not develop cerebral palsy.

We included 50 children born ≥35 weeks gestation cooled for NE who did not develop cerebral palsy. We assessed cognition using an average of cognitive and language composite scores (CLC) from Bayley Scales of Infant and Toddler Development (Bayley-III) at 18-21 months and full-scale IQ (FSIQ) on Wechsler Intelligence Scale for Children (WISC-IV) at 6-8 years. Linear regression was used to assess the association between CLC and FSIQ.

Our cohort's mean gestation was 39.8 (SD 1.6) weeks; 59% male. 80% had moderate NE. CLC scores were significantly associated with FSIQ (Coef 0.45 (95% CI: 0.17, 0.72), R² 19%). About 45% of children's cognitive scores lowered from 18 to 21 months to 6-8 years of age, with two FSIQ clusters differing by deprivation (7.3 vs 5.5, p = 0.009). Increasing CLC threshold to 95 still did not identify 63% having an FSIQ < 85.

Bayley-III underestimates the delay at school age in children cooled for NE. Childhood IQ after NE appeared to be patterned by local deprivation.

Bayley-III underestimates school-age delays in children cooled for neonatal encephalopathy secondary to perinatal asphyxia (NE). Around 45% of children's cognitive scores moved to a lower developmental range at school age. Increasing the Bayley-III threshold to 95 failed to identify nearly two-thirds of children with IQ < 85. Childhood IQ after NE appeared to be patterned by local deprivation. Longitudinal monitoring of children cooled for neonatal encephalopathy secondary to perinatal asphyxia is needed to support their cognitive development.