Abstract
PURPOSE: The purpose of the study was to conduct an individual-level analysis of hospital utilization during the first year of life to test the hypothesis that community material deprivation increases health care utilization. METHODS: We used a population-based perinatal data repository based on linkage of electronic health records from regional delivery hospitals to subsequent hospital utilization at the region's only dedicated children's hospital. Zero-inflated Poisson and Cox proportional hazards regression models were used to quantify the causal role of a census tract-based deprivation index on the total number, length, and time until hospital utilization during the first year of life. RESULTS: After adjusting for any neonatal intensive care unit admission, chronic complex conditions, race and ethnicity, insurance status, birth season, and very low birth weight, we found that a 10% increase in the deprivation index caused a 1.032-fold increase (95% confidence interval (CI), [1.025-1.040]) in post initial hospitalization length of stay, a 1.011-fold increase (95% CI, [1.002-1.021]) in number of post initial hospital encounters, and 1.022-fold increase (95% CI, [1.009-1.035]) in hazard for hospitalization utilization during the first year of life. CONCLUSIONS: Interventions designed to reduce material deprivation and income inequalities could significantly reduce infant hospital utilization.