Do Early Intervention Programs for Low-Birth-Weight Infants Have a Sustained Beneficial Effect?
ABSTRACT & COMMENTARY
Synopsis: Significant beneficial effects of early intervention programs on cognitive-behavioral effects in low-birth-weight infants at three years of age had largely disappeared by eight years of age.
Source: McCarton CM, et al. Results at age eight years of early intervention for low-birth-weight premature infants. JAMA 1997;277:126-132.
A group of low-birth-weight (lbw) children participated in a randomized trial of special services during the first three years of life. At three years of age, a group of children who had received center-based educational intervention had significantly higher IQs and fewer behavioral problems compared to children who received only routine follow-up. When these same children were studied again at eight years of age, the considerable differences in cognitive and behavioral skills between the two groups had largely disappeared.
COMMENT BY SALLY E. SHAYWITZ, MD
Good evidence indicates that, compared to normal-birth-weight children, LBW infants perform more poorly on measures of intelligence and are at increased risk of learning disabilities and behavioral problems. The Infant Health and Development Program (IHDP) is the most recent randomized clinical trial to examine the effects of intervention during the first three years of life. The IHDP involved center-based educational intervention, home-based family support services, and pediatric follow-up; its aim was to reduce the cognitive, behavioral, and health problems of LBW premature infants. Previous follow-up reports indicate that at age 3, children in the intervention group, particularly those LBW children from the heaviest stratum (bw, 2001-2500 g), had significantly higher intelligence scores, higher scores on a measure of receptive vocabulary, and less evidence of behavioral problems than children from a comparison non-intervention group. The current report describes findings at age 8, the first time the IHDP children have been evaluated at school age. Results indicate that children from the heaviest weight stratum (but not from the bw £ 2000 g stratum) have slightly higher intelligence scores, better scores on a measure of receptive language, and better scores on mathematics achievement testing than do controls. No differences from controls were seen in the need for special education services or in the prevalence of parent-reported behavioral difficulties.
What does this mean? The results clearly suggest that it is very difficult to modulate the serious cognitive, academic, and behavioral consequences of LBW. What should not be overlooked, however, are the sustained effects of the intervention program on intelligence and receptive language that were observed in the heavier group. Whether the economic price (estimated at approximately $15,000 per year per child) justifies the very real but also relatively modest beneficial effects remains an open question and, as McCarton et al suggest, "indicate[s] a need to develop additional intervention strategies for LBW premature children that can provide sustained benefits." (Dr. Shaywitz is Professor of Pediatrics and Co-Director of the Center for the Study of Learning and Attention Disorders at Yale University School of Medicine.)