Cognitive outcome of early school-aged children born very preterm is not predicted by early short-term amplitude-integrated electroencephalography

Abstract

Aim: We investigated the association between early amplitude-integrated electroencephalography (aEEG) and cognitive outcome in very preterm infants at early school-age. Methods: This prospective cohort study, conducted in the Department of Neonatology, University Hospital Zurich, Switzerland, from 2009 to 2012, comprised of infants born at <32 weeks of gestation, who underwent continuous aEEG recording during the first 4 days of life. Cognitive outcome was assessed with the Kaufman-Assessment Battery for Children at 5 years. Univariate and multivariate logistic regressions were calculated between aEEG parameters and normal cognitive outcome, defined as an intelligence quotient (IQ) of at least 85. Results: The 118 (52.5% male) infants were born at a mean gestational age of 29.9 weeks and a mean birth weight of 1235 ± 363 g. We followed up 89 children at the age of five, and they had a mean IQ of 97.8 ± 12.7 with 21.3% under 85—and 2.2% had cerebral palsy. Univariate analyses found associations between aEEG measures and normal cognitive outcome, but these were no longer significant after adjustment for confounders. Socioeconomic status and neonatal morbidity were independent predictors of cognitive outcome. Conclusion: Early short-term aEEG did not predict later cognitive outcome in our cohort of very preterm infants.