Abstract Body (Do not enter title and authors here): Background: Patients with pediatric heart failure (HF) face significant morbidity and mortality. However, there are limited data describing neighborhood characteristics in pediatric HF patients or linking them to clinical outcomes. We used the Child Opportunity Index 3.0 (COI) to explore the association of neighborhood characteristics with in-hospital morbidity and mortality for children with HF.

Hypothesis: Children with heart failure who live in neighborhoods with a higher COI will have lower in-hospital mortality during heart failure hospitalizations.

Methods: This retrospective cohort study used the Pediatric Health Information System (PHIS), a national administrative database of tertiary care pediatric hospitals. Inpatient index encounters between January 2014 and December 2024 were identified for pediatric patients (< 18 years old) with HF and cardiomyopathy using ICD-10 codes. The primary exposure of interest was COI, a composite index of community resources pertinent to child health, categorized into quintiles based on a national distribution (Very Low [Reference], Low, Moderate, High, Very High). The primary outcome was in-hospital mortality. Demographic and clinical variables were abstracted. Associations were assessed using univariable and multivariable logistic or linear regression models, adjusted for sex, age, race, and primary payor.

Results: Our cohort consisted of 7,060 patients, which were 45% female and 52% white. The mean patient age was 8.4 ± 6.6 years, and the incidence of in-hospital mortality was 8.8%. Half of the cohort was either in the Very Low (n=2,034, 29%) or Low (n=1,521, 22%) COI quintiles. Non-white, Latino, and patients with public insurance were more likely to live in lower COI neighborhoods (p<0.001). There were no differences across COI quintiles in ICU admission, mechanical ventilation, mechanical circulatory support, or renal failure. However, after adjustment, patients with a Very High COI were less likely to experience in-hospital mortality than those with a Very Low COI (OR=0.73 95%CI [0.54, 0.99] p=0.048).

Conclusions: Many children admitted with HF have limited neighborhood resources. Those with higher neighborhood resources are more likely to survive to discharge, emphasizing the relationship between environmental factors and clinical outcomes in pediatric HF. More work is needed to better understand the mechanisms behind these associations and to improve outcomes for children regardless of where they live.