Combined smoking cessation and alcohol abstinence treatment for people experiencing homelessness: a randomized trial.

Introduction: In the United States, 80% of adults experiencing homelessness smoke combustible cigarettes. Power to Quit 2 (PTQ2) was a randomized clinical trial to test the efficacy of a combined smoking cessation and alcohol abstinence biobehavioral intervention, Intensive Smoking plus Alcohol (IS+A), versus Usual Care (UC) for adults experiencing homelessness.

Methods: PTQ2 was conducted in 2 urban homeless shelters in the Upper Midwest (2014-2018). People who smoked and reported hazardous alcohol use (N=344) were randomized to IS+A (10 sessions of cognitive behavioral therapy for smoking and alcohol cessation plus nicotine replacement therapy [NRT], n=168) or UC (educational session on smoking and alcohol cessation plus NRT, n=176). The primary hypothesis was that the intervention would result in greater biochemically verified 7-day point-prevalent smoking abstinence 26 weeks post-intervention compared with UC. Our secondary hypothesis was that the intervention would result in greater 30-day alcohol abstinence 26 weeks post-intervention compared with UC.

Results: At week 26, the IS+A intervention group did not differ from the UC group in expired carbon monoxide-verified 7-day point-prevalent smoking abstinence (16.6% vs. 12.8%, P=0.47) or rate of self-reported 30-day alcohol abstinence (91.1% vs. 90.2%, P=0.75).

Conclusions: The IS+A intervention did not result in significantly better smoking or alcohol cessation outcomes than UC. Nonetheless, trends in the smoking outcome data favored the intervention group, underscoring the importance of continued research into bio-behavioral interventions that address smoking and alcohol use among adults experiencing homelessness.

Implications: The study highlights the difficulty in observing changes in smoking outcomes in interventions tailored to concurrently address smoking and alcohol use among persons experiencing homelessness. The findings add to existing knowledge by providing evidence about the real-world complexities facing people who use tobacco and alcohol while experiencing homelessness.