SCHOOL-AGE OUTCOMES IN CHILDREN WITH BIRTH WEIGHTS UNDER 750 G

Background. Since the mid-1980s, increasing numbers of children with b irth weights under 750 g have survived to school age. Methods. We matc hed a regional cohort of 68 surviving children born from 1982 through 1986 with birth weights under 750 g (mean, 670 g; gestational age, 25. 7 weeks) with 65 children weighing 750 to 1499 g at birth and 61 child ren born at term. Growth, neurosensory status, and functioning at scho ol age in the three groups were compared. Associations of biologic and social risk factors with major developmental outcomes were examined b y means of logistic-regression analyses. Results. Children with birth weights under 750 g were inferior to both comparison groups in cogniti ve ability, psychomotor skills, and academic achievement. They had poo rer social skills and adaptive behavior and more behavioral and attent ion problems. The mean (+/- SD) Mental Processing Composite score for the cohort was 87 +/- 15, as compared with 93 +/- 14 for children with birth weights of 750 to 1499 g and 100 +/- 13 for children born at te rm (P<0.001). The rates of mental retardation (IQ <70) in the three gr oups were 21, 8, and 2 percent, respectively; the rates of cerebral pa lsy were 9, 6, and 0 percent; and the rates of severe visual disabilit y were 25, 5, and 2 percent. Major cerebral ultrasonographic abnormali ties were associated with mental retardation (odds ratio, 5.4; 95 perc ent confidence interval, 1.8 to 15.8) and cerebral palsy (odds ratio, 15.2; 95 percent confidence interval, 3.0 to 77.4). Oxygen dependence at 36 weeks of corrected age was associated with mental retardation (o dds ratio, 4.5; 95 percent confidence interval, 1.2 to 10.7) and sever e visual disability (odds ratio, 4.3; 95 percent confidence interval, 1.3 to 14.2). Social disadvantage, though associated with several neur opsychological outcomes, was not associated with major developmental i mpairment. Conclusions. Children with birth weights under 750 g who su rvive represent a subgroup of very-low-birth-weight children who are a t high risk for neurobehavioral dysfunction and poor school performanc e.