Outcomes of intraventricular hemorrhage and posthemorrhagic hydrocephalus in a population-based cohort of very preterm infants born to residents of Nova Scotia from 1993 to 2010

Abstract

OBJECT Intraventicular hemorrhage (IVH) is a common complication of preterm birth, and the prognosis of IVH is incompletely characterized. The objective of this study was to describe the outcomes of IVH in a population-based cohort with minimal selection bias. METHODS All very preterm (≥ 30 completed weeks) patients born in the province of Nova Scotia were included in a comprehensive database. This database was screened for infants born to residents of Nova Scotia from January 1, 1993, to December 31, 2010. Among very preterm infants successfully resuscitated at birth, the numbers of infants who died, were disabled, developed cerebral palsy, developed hydrocephalus, were blind, were deaf, or had cognitive/language scores assessed were analyzed by IVH grade. The relative risk of each outcome was calculated (relative to the risk for infants without IVH). RESULTS Grades 2, 3, and 4 IVH were significantly associated with an increased overall mortality, primarily in the neonatal period, and the risk increased with increasing grade of IVH. Grade 4 IVH was significantly associated with an increased risk of disability (RR 2.00, p < 0.001), and the disability appeared to be primarily due to cerebral palsy (RR 6.07, p < 0.001) and cognitive impairment (difference in mean MDI scores between Grade 4 IVH and no IVH: -19.7, p < 0.001). No infants with Grade 1 or 2 IVH developed hydrocephalus, and hydrocephalus and CSF shunting were not associated with poorer outcomes when controlling for IVH grade. CONCLUSIONS Grades 1 and 2 IVH have much better outcomes than Grades 3 or 4, including a 0% risk of hydrocephalus in the Grade 1 and 2 IVH cohort. Given the low risk of selection bias, the results of this study may be helpful in discussing prognosis with families of very preterm infants diagnosed with IVH.

Keywords: BSID II = Bayley Scales of Infant Development, Second Edition; BSTID III = Bayley Scales of Infant and Toddler Development, Third Edition; CP = cerebral palsy; CPR = cardiopulmonary resuscitation; IVH = intraventricular hemorrhage; MDI = Mental Development Index (of BSID II); PFUP = Perinatal Follow-Up Program; PHH = posthemorrhagic hydrocephalus; PVL = periventricular leukomalacia; hydrocephalus; intraventricular hemorrhage; outcome; prematurity; vascular disorders.