Association between homelessness and opioid overdose and opioid-related hospital admissions/emergency department visits

Background: Although homelessness and opioid overdose are major public health issues in the U.S., evidence is limited as to whether homelessness is associated with an increased risk of opioid overdose. Objective: To compare opioid-related outcomes between homeless versus housed individuals in low-income communities. Design, Setting, and Participants: Cross-sectional analysis of individuals who had at least one ED visit or hospitalization in four states (Florida, Maryland, Massachusetts, and New York) in 2014. Measurements: Risk of opioid overdose and opioid-related ED visits/hospital admissions were compared between homeless versus low-income housed individuals, adjusting for patient characteristics and hospital-specific fixed effects (effectively comparing homeless versus low-income housed individuals treated at the same hospital). We also examined whether risk of opioid-related outcomes varied by patients' sex and race/ethnicity. Results: A total of 96,099 homeless and 2,869,230 low-income housed individuals were analyzed. Homeless individuals had significantly higher risk of opioid overdose (adjusted risk, 1.8% for homeless vs. 0.3% for low-income housed individuals; adjusted risk difference [aRD], +1.5%; 95%CI, +1.0% to +2.0%; p < 0.001) and opioid-related ED visit/hospital admission (10.4% vs. 1.5%; aRD, +8.9%; 95%CI, +7.2% to +10.6%; p < 0.001) compared to low-income housed individuals. Non-Hispanic White females had the highest risk among the homeless population, whereas non-Hispanic White males had the highest risk among the low-income housed population. Limitations: Individuals with no ED visit or hospitalization in 2014 were not included. Conclusion: Homeless individuals had disproportionately higher adjusted risk of opioid-related outcomes compared to low-income housed individuals treated at the same hospital. Among homeless individuals, non-Hispanic White females incurred the highest risk. These findings highlight the importance of recognizing the homeless population-especially the non-Hispanic White female homeless population-as a high-risk population for opioid overdose.