TOP 68 - Seizures in Neonatal Encephalopathy: Impact on Early Regional Brain Volumes and Early School-Age Cognitive Function

Publication Number: 3799.TOP 68

Medha Goyal, The Hospital for Sick Children, Toronto, ON, Canada; Ting Guo, The Hospital for Sick Children, Toronto, ON, Canada; Daphne Kamino, The Hospital for Sick Children, Toronto, ON, Canada; Jessy Parokaran Varghese, The Hospital for Sick Children, Toronto, ON, Canada; Elysa Widjaja, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, United States; Tricia Williams, The Hospital for Sick Children, Toronto, ON, Canada; Elana Pinchefsky, Sainte-Justine Hospital, Montreal, PQ, Canada; Cecil Hahn, The Hospital for Sick Children, Toronto, ON, Canada; Emily WY. Tam, The Hospital for Sick Children, Toronto, ON, Canada

Background: Neonatal encephalopathy (NE) is associated with a high incidence (50-80%) of seizures. High seizure burden (SB) has been independently linked to higher MRI brain injury scores following therapeutic hypothermia. However, the impact of SB on early regional brain volumes and long-term outcomes remains to be explored.

Objective: To determine the impact of SB on postnatal thalamic volumes and its association with cognitive function, including memory, visuospatial abilities, learning and emotional regulation at early school-age.

Design/Methods: The NOGIN (Neurological Outcome of Glycemia in Neonatal Encephalopathy) study comprises 102 neonates (≥ 36 weeks' gestational age) with NE. Data available include 48 hours of continuous electroencephalography monitoring and a post-rewarming MRI brain on day 3-5 of life, from which we will determine SB and thalamic volumes, respectively. Follow-up data at 5-6 years of age is available for 60 (59%) patients (7 patients died before follow-up, 12 were lost to follow-up, 11 declined, 7 did not meet the 5-year follow-up criteria, and 5 could not attend due to active COVID pandemic protocols). Early school-age outcomes have been assessed using measures of intellectual and language function (Wechsler Preschool and Primary Scale of Intelligence, 4th edition [WPPSI-IV]) and visuomotor, attention, and emotion regulation (Developmental Neuropsychological Assessment, 2nd edition [NEPSY-II]). Linear regression analysis will be performed to investigate the associations between SB and thalamic volumes, adjusting for umbilical artery pH, 5-minute Apgar score, and Sarnat score. Associations between SB and early school-age outcomes will be analyzed and adjusted for parental education, a measure of socioeconomic status. Data extraction will be completed by December 2025, and analyses will be completed by January 2026.