Obtaining housing associated with achieving abstinence after detoxification in adults with addiction Tae Woo Park, Christine Maynié-François, Richard Saitz Boston University Schools of Medicine and Public Health and Boston Medical Center

Background Addiction is common in homeless persons Approximately half of homeless adults have substance use disorders Homelessness associated with poor prognosis Increased morbidity Increased mortality High health service use

Background Detoxification often point of entry to addiction treatment for homeless substance users Impact of housing on achieving abstinence after detoxification is unclear

Objective To study the prospective association between housing and later abstinence in a cohort of adults with substance dependence post- detoxification

Hypothesis Obtaining housing is associated with a greater probability of later abstinence in homeless adults with substance dependence compared to continuous homelessness

Data source Secondary analysis of randomized clinical trial that compared integrated addiction, medical and mental health care with usual separate care No effect of integrated care on abstinence at 12 months (primary outcome)

Study design Cohort study Data collected prospectively Analyses and hypothesis completed after data collected Study period: 12 months

Study population Adults with alcohol and/or drug dependence (CIDI-SF) and recent heavy alcohol or drug use Screened at inpatient detoxification unit (74% of the whole RCT population, N = 416) Exclusion criteria: pregnancy, cognitive impairment, lack of English or Spanish fluency

Main independent variable Housing status (at baseline and 6 months) Continuously homeless Homelessness defined as any night on the street or in a shelter in the past 3 months Continuously housed Homeless to housed Housed to homeless

Outcomes 30-day abstinence from heavy drinking, stimulants and opioids at 12 months assessed by the Addiction Severity Index

Analysis Logistic regression model Adjusted for: ◦ Socio-demographics ◦ Age, sex, race ◦ Physical and mental health measures ◦ SF-12 PCS, PHQ-9 ◦ Addiction characteristics ◦ Both alcohol and drug dependence, ASI drug and alcohol composite scores, past addiction treatment

Results Baseline characteristicTotal (n=416) Age (SD)36 (10) Male gender (%)74 White race (%)56 Both alcohol and drug dependence (%)61 Addiction Severity Index – alcohol (SD)0.45 (0.35) Addiction Severity Index – drug (SD)0.32 (0.14) PHQ-9 ≥ 1089 Any addiction treatment past 3 months (%)62 SF-12 Physical Component Summary (%)42 (8)

Results Housing status (n=350)% Continuously homeless27 Continuously housed33 Housed to homeless6 Homeless to housed33

Association between housing status and abstinence Housing status (n=338) Odds ratio*95% CIP-value Continuously homeless (ref)1.00N/A Continuously housed Housed to homeless Homeless to housed *Adjusted for socio-demographics, physical and mental health measures, and addiction characteristics

Conclusion Among adults with substance dependence undergoing detoxification, those who transitioned from homelessness to being housed were more likely to achieve abstinence 12 months later compared to those continuously homeless

Limitations Examined housing status at only 2 time points Results may be confounded by unmeasured differences between those who gained housing and those that did not

Implications Provision of housing might improve addiction outcomes in patients with substance dependence leaving detox

Acknowledgments NIH/NIAAA R01 AA and NIH/NIDA R01 DA010019, Addiction Health Evaluation And Disease Management (AHEAD) Study, PI Saitz