Introduction Brain activity of preterm infants can be assessed by amplitude integrated electroencephalography (aEEG).
Objective To determine whether early aEEGs of preterm infants are associated with functional outcome at 7 years.
Methods Eighteen infants participating in a prospective observational study in 2004 were seen for follow-up at median age of 7 years, 5 months. Median GA was 28.9wks (26.7–32.9). aEEGs of 2h duration were recorded within 48h and one and two weeks after birth. aEEGs were assessed by pattern recognition and by calculating the mean of aEEG amplitude centiles. Functional outcome was determined by assessing intelligence, attention, verbal memory, visuospatial processing, executive functioning and motor skills.
Results In case of burst suppression < 48h Total IQ was 13 points lower (P=0.018), Performance IQ was 18 points lower (P=0.016) and visuospatial processing scores were 0.68 SD lower (P=0.027). Mean p5 and p50 centiles recorded < 48h after birth correlated positively with Total IQ (r=0.507, r=0.495, repectively; P<0.05), Performance IQ (r=0.578, r=0.514, respectively; P<0.05), selective attention (r=0.586, r=0.577, respectively; P<0.05), visuospatial processing (r=0.488, r=0.534, respectively; P<0.05) and fine motor skills (r=0.558, r=0.556, respectively; P<0.05). All correlations remained significant at one week and after adjustment for GA, except for visuospatial processing and fine motor skills.
Conclusion Burst suppression and lower aEEG amplitude centiles within 48hrs and at one week after birth were associated with poorer cognition at 7 years. This indicates that early aEEGs may be useful in predicting functional outcome of preterm children at school age.