P2.H144: Trends of Neonatal Seizure Prevalence Among Infants with Grade 3 and 4 Intraventricular Hemorrhage and Associated Mortality in the United States

Background: Neonatal seizures are common in premature infants with intraventricular hemorrhage (IVH), yet their precise incidence and associated mortality remain unclear. Studies have shown that infants with grade 4 IVH are more susceptible to acute seizures, and only those with grades 3 and 4 IVH develop remote seizures, which are identified as significant risk factors for subsequent adverse outcomes. Additionally, research highlights the correlation between neonatal seizures and long-term neurodevelopmental disabilities, emphasizing the need for further investigation into optimal monitoring strategies for early detection and intervention.

Methods: This study used data extracted from the Healthcare Cost and Utilization Project (HCUP) database from 2003 to 2020. The study included infants with gestational age less or equal to 28 weeks with documented intraventricular hemorrhage grades 3 or 4. We excluded those with CNS anomalies, congenital heart disease, congenital diaphragmatic hernia, lung anomalies, abdominal wall defects, multiple congenital anomalies and chromosomal abnormalities. We calculated trends in severe IVH and seizures prevalence using chi-square testing and logistic regression models to control for confounders.

Results: A total of 513,773 infants were included. Prevalence of severe IVH was 6.6% (present in 33,984) and of seizure was 2.1% (present in 10,850). The unadjusted odds ratio of having seizures with severe IVH was 12% compared to those without severe IVH at 1.4%. The adjusted odds ratio of those infants with seizures in the presence of severe IVH compared to no IVH was 7.3 (CI 6.9-7.7), p< 0.0001). The factors with strongest association with severe IVH were acute renal failure (odds ratio, 2.92; 95% confidence interval 2.7-3.2), neonatal sepsis (odds ratio, 2.3; 95% confidence interval 2.2-2.5), and pulmonary hemorrhage (odds ratio, 1.8; 95% confidence interval 1.6-2). The prevalence of severe IVH and seizures has slightly fluctuated but overall, it did not statistically change over the years. The adjusted odds ratio of death of those infants with seizures in the presence of severe IVH compared to those without seizures in severe IVH was 1.4 (CI 1.3-1.5, p< 0.0001).

Conclusion: This study provides insights into the prevalence of seizures in premature infants with severe intraventricular hemorrhage compared to those without, as well as associated confounding factors and mortality rates. The study revealed that premature infants with severe IVH have a significantly higher risk of experiencing seizures compared to those without severe IVH, with acute renal failure, neonatal sepsis, pulmonary hemorrhage, and necrotizing enterocolitis strongly associated with severe IVH. Despite slight fluctuations, the prevalence of severe IVH and seizures remained statistically unchanged over the study period, yet the presence of seizures in infants with severe IVH significantly increased the odds of mortality. These findings underscore the critical need for targeted interventions and monitoring strategies to mitigate the risks and improve outcomes for this vulnerable population.