Impact of intraventricular hemorrhage on cognitive and behavioral outcomes at 18 years of age in low birth weight preterm infants.

OBJECTIVE: Although high-grade intraventricular hemorrhage (IVH; grades III-IV) in preterm and low birth weight infants are clearly associated with increased risk of long-term adverse neurodevelopmental sequelae, the impact of low-grade IVH (grades I-II) has been less clear. Some studies have followed these infants through early school age and have shown some conflicting results regarding cognitive outcome. Such studies that assess children at younger ages may not accurately predict outcomes in later childhood, as it is known that fluid and crystallized intelligence peak at age 26 years. There is paucity of data in current medical literature, which correlates low-grade IVH with outcomes in early adulthood. To determine the link between the occurrence of low-grade IVH in low birth weight (birth weight ⩽2500 g) infants born prematurely (gestational age <37 weeks) and intellectual function, academic achievement, and behavioral problems to the age of 18 years.

STUDY DESIGN: This study is an analysis of data derived from the Infant Health and Development Program (IHDP), a multisite national collaborative study and a randomized controlled trial of education intervention for low birth weight infants from birth until 3 years of age with follow-up through 18 years of age. A total of 985 infants were enrolled in the IHDP. Of the 462 infants tested for IVH, 99 demonstrated sonographic evidence of low-grade IVH, whereas 291 showed no sonographic evidence of IVH. Several outcomes were compared between these two groups. Intelligence was assessed using Stanford-Binet Intelligence scales at age 3 years, Wechsler Intelligence Scale for Children (WISC-III) at age 8 years, Wechsler Abbreviated Scale of Intelligence (WASI) at age 18 years and Woodcock Johnson Tests of Achievement at age 8 and 18 years. Behavior was measured using the Achenbach Behavior Checklist at age 3 years and Child Behavior Checklist (CBCL) at age 8 and 18 years. Outcomes were compared between the IVH-positive and IVH-negative groups using analysis of covariance after adjusting for the presence or absence of intervention, birth weight, gestational age, gender, severity of neonatal course, race and maternal education.

RESULTS: No statistically significant difference in intelligence as measured by Stanford-Binet Intelligence scales, WISC-III, WASI and Woodcock-Johnson Tests of Achievement could be appreciated between IVH-positive patients and controls at any age group (36 months, 8 years and 18 years of age). In addition, there was no significant difference in problem behavior as assessed by the Achenbach Behavior Checklist and Child Behavior Checklist (CBCL) comparing IVH patients with controls.

CONCLUSION: Low-grade IVH was not demonstrated in our study to be an independent risk factor associated with lower outcomes in intelligence, academic achievement or problem behavior at age 3, 8 and 18 years.