The Predictive Value of Amplitude-Integrated Electroencephalography in Preterm Infants for IQ and Other Neuropsychological Outcomes at Early School Age

BACKGROUND: Amplitude-integrated electroencephalography (aEEG) is used increasingly in neonatal intensive care and seems helpful in predicting outcomes at the age of 2 years. OBJECTIVES: To determine whether early aEEG patterns in preterm infants are equally useful in predicting outcomes at early school age. METHODS: We recorded aEEG in 41 preterms (gestational age 26.0–32.9 weeks) at a median postnatal age of 9.7 h (IQR 7.0–25.3) and in 43 preterms on median day 8 (IQR 7–9). We assessed aEEG by pattern recognition and calculated the means of the aEEG amplitude centiles. At a median of 7.39 years, i.e., early school age, we assessed their motor, cognitive, and behavioral outcomes. RESULTS: Depressed aEEG patterns were not associated with poorer outcomes. Cyclicity directly after birth was associated with a higher total IQ (mean 104 vs. 97, p = 0.05) and higher scores on visual perception (mean percentile 57.1 vs. 40.1, p = 0.049) and visual memory (mean percentile 34.5 vs. 19.1, p = 0.090). We found some associations between the aEEG amplitude centiles and cognitive outcomes, but none for motor or behavioral outcomes. There was an increased risk of abnormal scores on long-term verbal memory in cases of the lower 5th and 50th aEEG amplitude centiles directly after birth. The odds ratios were 0.65 (95% CI 0.42–0.99, p = 0.040) and 0.71 (95% CI 0.52–0.96, p = 0.025), respectively. CONCLUSIONS: In relatively healthy preterm infants the value of aEEG in predicting neuropsychological outcomes at early school age is limited. The presence of cyclicity directly after birth tends to be associated with better cognition.