Methods: This study utilized baseline data from an innovative, mixed-methods study to understand risk environments of young adults who are homeless. Youth (aged 18-29) were recruited from housing programs and drop-in centers in Los Angeles and followed intensively for one week with momentary assessment measures. Both housed (n=137) and unhoused (n=128) participants completed a self-administered baseline questionnaire that captured demographic characteristics as well as lifetime, past three month, and past 30-day alcohol, marijuana, tobacco, and other hard drug use (i.e., methamphetamine, ecstasy, hallucinogens, cocaine, crack, inhalants, nitrous, ketamine, prescription drug misuse, or Phencyclidine). Participants also completed the 4-item CAGE screener for alcohol use disorders and reported any past history of substance use treatment.
Results: Unhoused participants were more likely to report past three-month marijuana use (OR: 0.40, 95% CI:0.24-0.69, p<0.001) and more likely to report marijuana use in the past 30-days (OR: 0.40, 95% CI:0.24-0.67, p<0.001) than housed participants. Similarly, compared to participants in housing, unhoused participants were more likely to report past three-month tobacco use (OR: 2.85, 95% CI:1.22-6.65, p<0.01) and also more likely to smoke tobacco in the past 30-days (OR: 0.54, 95% CI:0.33-0.89, p<0.01). Lastly, participants that were unhoused were more likely to use hard drugs in the past three months (OR: 0.40, 95% CI:0.24-0.71, p<0.001) and more likely to use one these hard substances within the past 30-days (OR: 0.31, 95% CI:0.15-0.62, p<0.001) than housed participants. There were no statistically significant differences in lifetime use of tobacco, marijuana, or other hard drugs between participants in housing or those who were homeless. Unhoused and housed participants did not differ on lifetime or recent alcohol use. Both participant populations had a similar prevalence of past substance use treatment (30%) as well as prevalence of probable alcohol use disorder (48%).
Conclusions and Implications: While both housed and unhoused participants had similar lifetime use rates of tobacco, marijuana, and other hard drugs, young adults without a residence are significantly more likely to report recent use. These findings suggest that housing may provide stability that results in less risky behavior. Though housing may decrease use of some types of substances, both housed and unhoused youth reported high rates of recent alcohol use. More research is needed to determine contextual factors that may impact risk behavior and if supportive services available in housing programs (e.g., mental health treatment) may result in less recent substance use of youth.