Trajectories of alcohol and cannabis use among emerging adults with a history of unstable housing: Associations with functioning over a two-year period

Abstract

Introduction: Research has documented high rates of alcohol and cannabis use among emerging adults experiencing homelessness. However, little is known about trajectories of use over time or how trajectories are associated with functioning (e.g., risk behaviors, mental and physical health, social functioning, economic well-being).

Methods: Data come from a cohort of 18-25 year olds experiencing homelessness who were surveyed 5 times over 24 months. Parallel process growth mixture models were used to model heterogeneity in alcohol and cannabis use across the 5 timepoints, which allowed for the extraction of classes based on both alcohol and cannabis use trajectories. Classes were compared on demographics and functioning at baseline and 24-months.

Results: Two trajectory classes of alcohol and cannabis use emerged: moderate decreasing cannabis and low stable alcohol use (75% of the sample) and heavy cannabis and alcohol use (25% of the sample). The heavy cannabis and alcohol use class reported a significantly higher likelihood for any non-cannabis drug use at baseline and 24-months, as well as greater depression and physical ailments at 24-months. In addition, at 24-months this class had a marginally higher likelihood of a positive screen for at least moderate anxiety and being recently unhoused.

Conclusions: The effects of heavy continued cannabis and alcohol co-use on multiple domains of functioning (e.g., risk behavior, mental and physical health) highlight the importance of a coordinated systems approach that addresses the often complex and interrelated challenges facing emerging adults with a history of homelessness.

Keywords: Functional outcomes; Homeless; Substance use; Trajectories; Young adult.