Prevalence of substance use and associated risk factors among homeless youth in Iran: A cross-sectional study

•Homeless youth in our survey had high levels of substance use; over one third reported heroin use, nearly one third reported alcohol use, and one fourth reported methamphetamine use in the last month.•Homeless youth who were older, male, used tobacco, and were completely homeless had higher odds of substance use.•Innovative programs are needed to address substance use and competing social welfare needs of homeless youth in Iran. Homeless youth are at increased risk of substance use and its consequences worldwide. Substance use among youth who are homeless has not been as well studied, particularly in developing country settings. We therefore aimed to assess the prevalence and correlates of substance use among homeless youth in Kerman, a city in southeast Iran. In a cross-sectional survey by convenience sampling, we recruited 202 homeless youth from September to December 2017. Data were collected in face-to-face interviews using a standardized questionnaire. Youth were eligible if they were 15–29 years old and homeless or unstably housed for at least one month during last year. Factors associated with substance use were characterized by multivariable logistic regression analysis. In our survey, 50.0% (95% CI 43.0–56.9) of homeless youth reported substance use in the last month. The most common substances used were heroin (34.0%), alcohol (31.2% – illegal in Iran), and methamphetamine (24.0%). Substance use was associated with male sex (adjusted odds ratio [AOR] 6.57, 95% CI 2.72, 15.85), age 25–29 vs. 15–24 years (AOR 4.02, 95% CI 1.57, 10.29), current tobacco use (AOR 6.49, 95% CI 2.63, 16.00), and absolute homelessness vs. relative homelessness (AOR 7.75, 95% CI 2.90, 20.68). Findings highlight the need for prevention programs to reduce substance use-related harm among homeless youth, particularly among tobacco users and those completely homeless. Innovative strategies are needed reach the absolutely homeless and simultaneously address the substance use and competing social welfare needs of this vulnerable population.