Background Unstable housing and homelessness is prevalent among injection drug users (IDU). stable housing in a multivariate model (adjusted hazard ratio [AHR] ?=?0.71; 95% CI: 0.52C0.96). Being in a partnered relationship was positively associated with the primary outcome (AHR ?=?1.39; 95% CI: 1.02C1.88). Receipt of income assistance (AHR ?=?0.65; 95% CI: 0.44C0.96), daily crack use (AHR ?=?0.69; 95% CI: 0.51C0.93) and daily heroin use (AHR ?=?0.63; 95% CI: 0.43C0.92) were negatively associated with attaining stable housing. Conclusions Exposure to addiction treatment in our study was negatively associated with attaining stable housing and may have represented a marker of instability among this sample of IDU. Efforts to stably house this vulnerable group may be occurring in contexts outside of addiction treatment. Introduction Addiction and homelessness are often co-occurring conditions. Addiction is characterized by the persistent use of alcohol or drugs despite negative consequences to the one’s health and the loss of social functioning related to the substance use. Untreated, addiction can result in significant morbidity and mortality [1], [2]. Homelessness is also an independent risk factor for morbidity and mortality [3]C[7] and both addiction and homelessness are associated with significant service utilization and costs to the health, criminal justice and social welfare systems [8]C[13]. The underlying reasons for homelessness are complex, although previous studies have shown that substance use (illicit drugs and alcohol) is prevalent among persons who are homeless [14]C[16], with substance use potentially being a cause or consequence of homelessness. In order to mitigate the harms associated with a lack of housing, numerous trials have been conducted to examine the impact of housing interventions such as Housing First approaches on the residential trajectory of chronically homeless persons with severe and persistent mental illness. The proportion of study participants in the Housing First studies who had severe substance use problems was relatively low [17], potentially limiting its generalizability to this group. Recently published studies of Housing First have found favourable outcomes among chronically homeless alcoholics in Seattle; however, there was no mention of illicit drug use in the sample [18]. A study of homeless persons in Chicago with chronic medical conditions 1169562-71-3 who used the medical services frequently also reported a reduction in medical service utilization. Of their sample, 60% reported using illicit drugs in the previous 30 days but no further details regarding 1169562-71-3 type or frequency of drug use were provided [19]. Thus, these findings may not be generalizable to 1169562-71-3 active drug users. In contrast, linear approach programs [20], common in the United States, are focused on achieving abstinence and require persons who are homeless and have substance abuse problems to engage in intensive addiction treatment programs as a prerequisite to maintaining temporary housing. One linear approach program has been extensively studied over the past 12 years 1169562-71-3 in Birmingham, Alabama and uses abstinence contingent housing among homeless persons with cocaine dependence [21]C[24]. A meta-analysis of the four randomized controlled trials found that drug abstinence was higher in the abstinent contingent housing arm compared to the arm that offered only day treatment (58% vs. 26%) at six months [25]. Interestingly, a small retrospective study that compared homeless patients receiving office-based buprenorphine treatment to housed patients found that the homeless patients had similar outcomes with respect to illicit drug use, treatment failure and use of addiction treatment despite having higher social instability, greater comorbidities, and more chronic drug use compared to the housed individuals in this study. Furthermore, 36% of the homeless group was housed at twelve months [26]. The focus of addiction treatment is generally to reduce illicit drug use and improve social, vocational and interpersonal functioning, which would include attaining stable housing for homeless individuals. Illicit drug use is prevalent in the Downtown Eastside neighbourhood of Vancouver, Canada and the proportion of drug users who are Mouse monoclonal to CEA also using crack has been increasing [27]C[29]. Addiction treatment, including methadone.