P2C203: Neurodevelopmental Outcomes of Neonates with Hypoxic-ischemic Encephalopathy: Role of Socioeconomic Vulnerability

Background: Outcomes of infants with hypoxic ischemic encephalopathy (HIE) are better in those who attend follow-up clinic compared to those who do not. Unfortunately, global rates of follow-up clinic attendance remain poor. Multiple individual and family-level factors have been shown to impact participation in follow-up care; however, there is limited literature examining how community and neighborhood characteristics affect healthcare utilization and neurodevelopmental outcomes in these neonates. We aim to examine the relationship between socioeconomic vulnerability and neurodevelopmental outcomes in neonates with HIE.

Methods: 66 infants with moderate to severe HIE who underwent therapeutic hypothermia between 2010 and 2015 were enrolled in this study. Using electronic medical records, we obtained clinical and sociodemographic information about each infant, including birth anthropometrics, gestational age, sex, cord blood gas or initial infant gas pH and base excess, 1 and 5 minute APGAR scores, brain MRI results, peak creatinine and alanine transaminase levels, and county of residence. We used the CDC Social Vulnerability Index (SVI), a well-validated metric comprised of 16 US Census indicators, to assess vulnerability at the county level. We used a combination of Capute and Mullen scores to assess motor and cognitive development at 24 months, and categorized outcomes as typical, moderate impairment or severe impairment. Logistic regression was performed to assess differences in cognitive and overall neurodevelopmental outcomes by SVI quartiles for four key domains: socioeconomic status (SES), household characteristics, racial and ethnic minority status, and housing type and transportation. Linear regression was used for similar subset analysis of infants with Mullen scores.

Results: Among enrolled infants, there was a significant association between overall neurodevelopmental outcomes at 24 months and socioeconomic status (p = 0.016), household characteristics (p = 0.003), and housing type and transportation (p=0.005), even after adjusting for brain MRI grades. In both cognitive and overall outcomes, the lowest quartiles within each theme (Q1 and Q2), representing counties with decreased vulnerability, were associated with significantly decreased odds of moderate to severe disability compared to the highest quartile (Q4) (Figure 1). Mullen scores at 24 months were associated with socioeconomic status (p = 0.036), household characteristics (p = 0.01), racial and ethnic minority status (p= 0.04), and housing type and transportation (p= 0.007), even after adjusting for brain MRI grades. Within each domain, infants from areas of higher socioeconomic vulnerability had significantly lower Mullen scores than infants from areas with lower socioeconomic vulnerability.

Conclusion: Socioeconomic vulnerability across multiple domains is associated with poorer neurodevelopmental outcomes among infants with HIE. Further research elucidating the specific contributions of the individual SVI components to neurodevelopmental risk and follow-up clinic attrition will support the development of evidence-based, targeted interventions to improve attendance in high-risk follow-up clinics, allowing for improvement in outcomes and realization of each child’s full potential.