EEG for predicting early neurodevelopment in preterm infants: an observational cohort study.

OBJECTIVE To clarify the prognostic value of conventional EEG for the identification of preterm infants at risk for subsequent adverse neurodevelopment in the current perinatal care and medicine setting. METHODS We studied 780 EEG records of 333 preterm infants born <34 weeks' gestation between 2002 and 2008. Serial EEG recordings were conducted during 3 time periods; at least once each within days 6 (first period), during days 7 to 19 (second period), and days 20 to 36 (third period). The presence and the grade of EEG background abnormalities were assessed according to an established classification system. Neurodevelopmental outcomes were assessed at a corrected age of 12 to 18 months. RESULTS Of the 333 infants, 33 (10%) had developmental delay and 34 (10%) had cerebral palsy. The presence of EEG abnormalities was significantly predictive of developmental delay and cerebral palsy at all 3 time periods: the first period (n = 265; odds ratio [OR], 4.5; 95% confidence interval [CI], 2.2-9.4), the second period (n = 278; OR, 7.6; 95% CI, 3.6-16), and the third period (n = 237; OR, 5.9; 95% CI, 2.8-13). The grade of EEG abnormalities correlated with the incidence of developmental delay or cerebral palsy in all periods (P < .001). After controlling for other clinical variables, including severe brain injury, EEG abnormality in the second period was an independent predictor of developmental delay (OR, 3.2; 95% CI, 1.1-9.7) and cerebral palsy (OR, 6.8; 95% CI 2.0-23). CONCLUSIONS EEG abnormalities within the first month of life significantly predict adverse neurodevelopment at a corrected age of 12 to 18 months in the current preterm survivor.