Factors associated with frequent emergency department visits and hospitalizations among homeless people with Medicaid: Implications for health care reforms

Objective: We examined factors associated with frequent hospitalizations and emergency department (ED) visits among Medicaid insured homeless individuals to help states prepare for the upcoming Medicaid expansion. This study provides a unique perspective since most individuals in existing homeless studies are uninsured.

Methods: We identified 6,494 individuals from merged Boston Health Care for the Homeless Program (BHCHP) and Medicaid datasets in CY 2010. Variables examined included demographics, housing status, mental illness/substance use disorder (SUD) groups, and selected physical conditions. We used negative binomial regression to examine hospitalizations and ED visits because they are count data with over-dispersion.

Results: On average, homeless individuals had one hospitalization and four ED visits in CY2010. Multivariable analyses showed that homeless individuals with co-occurring mental illness and SUDs were at the greatest risk of frequent hospitalizations and ED visits (e.g., incidence rate ratio (IRR)=3.1 to 15.3 for hospitalizations) followed by those with schizophrenia or SUD alone. Most selected physical conditions were moderately associated with increased utilization (IRR=1.1 to 2.3). Additionally, unhoused individuals had significantly higher utilization than those who had supported housing (e.g., IRR=1.5 for hospitalizations among those lived on the street).

Conclusions: Homeless individuals experienced heavy inpatient and ED use, particularly those without stable housing and those with co-occurring mental illness and SUDs. States could consider provisions under the Affordable Care Act, e.g., Medicaid expansion and Health Homes, jointly with supportive housing to meet the needs of homeless individuals which may improve the quality and cost-effectiveness of care.