Social variables predict gains in cognitive scores across the preschool years in children with birth weights 500 to 1250 grams

J Pediatr. 2015 Apr;166(4):870-6.e1-2. doi: 10.1016/j.jpeds.2014.12.016. Epub 2015 Jan 29.


Objective: To determine the extent that social variables influence cognitive development of very low birth weight (VLBW) infants across the preschool years.

Study design: Participants were VLBW (500-1250 g) children enrolled in the Caffeine for Apnea of Prematurity randomized trial between 1999 and 2004. We investigated the relationships between 4 potential social advantages: higher maternal education, higher paternal education, caregiver employment, and 2 biologic parents in the same home--and gain in cognitive scores. Cognitive assessments were performed at the corrected ages of 18 months (Mental Development Index score on the Bayley Scales of Infant Development II) and 5 years (Full Scale IQ on the Wechsler Preschool and Primary Scale of Intelligence III). Cognitive gain was computed by subtracting each individual 18-month Mental Development Index score from the corresponding Full Scale IQ at 5 years.

Results: Data were available for 1347 children. Mean (SD) cognitive scores were 90.8 (15.7) at 18 months and 98.9 (14.5) at 5 years. Multivariable regression showed that higher maternal education, higher paternal education, and caregiver employment had independent and additive effects of similar size on cognitive gain (P < .001); the mean cognitive gain between 18 months and 5 years increased by 3.6 points in the presence of each of these advantages. When all 3 were present, cognitive scores improved on average by 10.9 points compared with children without any of these advantages.

Conclusion: In VLBW children, a count of 3 social advantages strongly predicts gains in cognitive scores across the preschool years.

Trial registration: NCT00182312.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Birth Weight / physiology*
  • Child Development / physiology*
  • Child, Preschool
  • Cognition / physiology*
  • Female
  • Follow-Up Studies
  • Humans
  • Infant
  • Infant, Premature*
  • Infant, Very Low Birth Weight / physiology*
  • Intelligence / physiology*
  • Male
  • Prognosis
  • Retrospective Studies

Associated data