Early intervention in low-birth-weight premature infants. Results through age 5 years from the Infant Health and Development Program.

OBJECTIVE

To evaluate the persistence of effects on health and development at age 5 years of the Infant Health and Development Program, an early childhood intervention that was provided to low-birth-weight (LBW) premature infants from neonatal discharge through age 3 years.

DESIGN

Randomized, controlled, multicenter trial, stratified by two LBW groups: lighter (< or = 2000 g) and heavier (2001 to 2500 g).

SETTING

Eight socioeconomically heterogeneous clinical sites.

PARTICIPANTS

Of 985 eligible infants weighing 2500 g or less and at 37 weeks' or less gestational age, 377 infants were randomly assigned to the intervention group and 608 to the follow-up only group. About two thirds of the infants in each group were in the lighter LBW stratum, and one third were in the heavier LBW stratum.

INTERVENTION

The intervention group received home visits (from neonatal discharge through age 3 years) as well as center-based schooling (from 1 to 3 years of age). Children in both groups received pediatric surveillance.

MAIN OUTCOME MEASURES

Cognitive development, behavioral competence, and health status.

RESULTS

At age 5 years, the intervention group had full-scale IQ scores similar to children in the follow-up only group. However, in the heavier LBW stratum, children in the intervention group had higher full-scale IQ scores (3.7 points higher; P = .03) and higher verbal IQ scores (4.2 points higher; P = .02). No significant differences between intervention and follow-up only groups in cognitive measures at age 5 years were noted in the lighter LBW infants. The intervention and follow-up groups were similar in behavior and health measures regardless of LBW stratum.

CONCLUSION

The early childhood intervention provided in the first 3 years of life had effects on heavier LBW premature infants' IQ and verbal performance at age 5 years that were not observed for lighter LBW premature infants. The intervention did not affect health or behavior at age 5 years in either LBW stratum.