Can Neonatal EEG act as Predictor of Neurodevelopmental Outcome in Preterm Infants?

Author(s): Md. Abdul Mannan*, Faria Yasmin, Asaduzzaman, Afrina Wahab, Anurakkhi Barua, Ayesha Siddika, Kanij Fatema, Shaheen Akhter

Background: Preterm infants are at high risk of neurodevelopmental delay including cognitive, motor impairment etc. Accurate recognition of infants at increased risk of abnormal neurodevelopmental outcome is challenging during the neonatal period. By predicting neuro-developmental outcome infants may benefit from early intervention, influencing positive outcomes. Electroencephalography (EEG) is used to evaluate brain function. Previous studies have shown that the EEG provides valuable information regarding brain function & possible neurodevelopmental outcome in preterm infants.

Methodology: To evaluate the role of EEG in predicting the neurodevelopmental outcome of preterm infants. This prospective observational study was conducted in NICU of Bangabandhu Sheikh Mujib Medical University & Institute of Pediatric Neuro-disorder and Autism (IPNA) over a period of one year. Neonates having gestation < 37 completed weeks admitted in NICU of BSMMU were being enrolled in the study. EEG of the enrolled babies was done during hospital admission in neurophysiology laboratory, IPNA, BSMMU. Assessment of neurodevelopmental status was performed at 6 months & 12 months of corrected age using the Bayley Scales of Infant and Toddler Development, Third Edition (BSITD-III). If score <70, it was considered as neurodevelopmental impairment. Hearing screen was done by Transient auto acoustic emission test with Hearing screener. Vision was assessed clinically as field of vision, visual equity and also by ophthalmoscope.

Results: During the study period, 123 neonates having gestational age <37 weeks were assessed for eligibility and 92 were enrolled in the study. EEG was done in all of the 92 neonates. Among them 12 were lost to follow up and 80 infants completed 12 months follow up and were included in the final analysis. Among the 80 neonates 51 (64%) had normal EEG and 29 (36%) had abnormal EEG. Total 23 (28.7%) had abnormal neurodevelopmental outcome at 12 months of age. Among them 20 (86.95%) were in the abnormal EEG group and 3 (13.04%) were in the normal EEG group. Abnormal neurodevelopmental outcome was significantly higher among the abnormal EEG group (p=<0.001). In the study population, neonates having abnormal EEG had significantly higher rate of perinatal asphyxia and neonatal seizure. Other morbidities didn’t show any significant difference. Both 6 months and 12 months neurodevelopmental assessment showed adverse outcomes in all domain are significantly higher among the abnormal EEG group. Logistic regression analysis also showed that abnormal neurodevelopmental outcome is significantly associated with abnormal EEG in preterm infants.

Conclusion: Preterm neonates having abnormal EEG findings during hospital stay had adverse neurodevelopmental outcome at 6 months and 12 months of age. Perinatal asphyxia and neonatal seizure were higher among abnormal EEG group.