Early Diet and General Cognitive Outcome at Adolescence in Children Born at or Below 30 Weeks Gestation

Abstract

To test the hypothesis that effects of early diet on cognition observed at age 8 years persist in adolescents born preterm at < or = 30 weeks gestational age. A subgroup from a preterm infant cohort recruited for a randomized trial studying the effects of early dietary intervention was assessed at age 16 years. IQ scores were compared between those assigned a high-nutrient diet (n = 49) or standard-nutrient diet (n = 46) in infancy at both 8 and 16 years. At age 8 years, the high-nutrient group had higher mean Verbal IQ (VIQ; P = .03), Performance IQ (P = .01), and Full-Scale IQ (P = .02) scores compared with the standard-nutrient group; the VIQ difference persisted at adolescence (P = .02). This effect was accounted for principally by a significant difference in the mean Verbal Comprehension Index score (P < .008). A brief period of dietary intervention after preterm birth, principally between 26 and 34 weeks of gestation, affected IQ at age 16 years. A standard-nutrient diet was associated with lower VIQ, accounted for mainly by differences in verbal comprehension, which persisted after control of social factors.