Neighborhood Child Opportunity and Racial Disparities in Readmissions for Diabetic Ketoacidosis Across U.S. Children’s Hospitals

Background: Previous studies have identified racial disparities among children with diabetic ketoacidosis (DKA). The Child Opportunity Index 2.0 (COI) was developed to assess neighborhood attributes that elucidate structural inequities and factors influencing health outcomes. We aimed to determine whether COI is associated with 1) frequency and timing of readmissions for DKA, and 2) complications from DKA, including cerebral edema and acute kidney injury (AKI).

Methods: We conducted a retrospective study among children <21 years discharged with a primary diagnosis of DKA based on International Classification of Disease (ICD) codes between January 1st, 2009 to December 31st, 2018 using data from the Pediatric Health Information System. COI was evaluated as an ordered, categorical score, where a higher score indicates greater opportunity (Figure 1). The primary outcome was readmission for DKA within 30 days and 365 days from an index emergency department visit. Secondary outcomes included the proportion of encounters with ICD-coded AKI or cerebral edema at the index visit. We used mixed-effects logistic regression model with random intercept for hospital and patient to generate predicted probabilities for readmission, AKI and CE for each racial group by COI after adjusting for age, sex, payer, intensive care unit admission, discharge year, race by COI interaction, and presence of complex chronic condition. Data are reported as predicted probabilities with standard errors of the predicted mean.

Results: Of 83,445 available encounters, 72,985 were included after applying exclusion criteria (Table 1). Approximately 25% of children had a readmission within 365 days (Table 1). Among non-Hispanic black children, the predicted probability of a readmission within 30 or 365 days was 5.1±0.4% and 24.9±0.9%, respectively, for those with very low COI, and this marginally decreased to 4.8%±0.7% (p=0.68) and 20.4%±1.5% (p < 0.001) for those with very high COI (Figure 1). In contrast, the predicted probability of a readmission within 30 or 365 days among non-Hispanic white children was 3.2±0.3% and 17.4±0.8%, respectively, for those with very low COI, and 2.1±0.2% (p < 0.001) and 11.2±0.6% (p < 0.001) for those with very high COI. At all COI levels, non-Hispanic white children had a significantly lower probability of readmission for DKA within 30 and 365 days compared to non-Hispanic black children (p < 0.05). COI was not a significant predictor of AKI (p=0.10) or cerebral edema (p=0.16). However, non-Hispanic black children had 60% greater odds of AKI compared to non-Hispanic white children (95% CI: 1.42, 1.80). The association between race and cerebral edema at initial presentation was non-significant (p=0.05).

Conclusion: Readmissions for DKA were more common for non-Hispanic black children compared to non-Hispanic white children at every COI level. However, COI was not a significant predictor of DKA-related AKI or cerebral edema. Measures to prevent DKA readmissions should include interventions aimed at neighborhood and community factors.