Cross-sectional Toronto study links mental health, housing to substance outcomes

A cross-sectional analysis of clinical records at Casey House, a specialty hospital in Toronto, found that better mental health and greater housing stability were associated with more favorable substance use ratings, while health care access had a smaller and less consistent relationship. The study examined 708 records with a substance use rating collected between January 2022 and September 2025. Of these records, 37.6% were classified as Urgent/High Need on a five-point continuum that ranged from Urgent Need to Thriving.

Researchers used clinician-assigned baseline assessments recorded with the Multipurpose Resilience Assessment Tool in a harm reduction–oriented clinical setting. Ordered logistic regression models assessed the relationships between mental health status, housing stability, access to health care and substance use ratings. The investigators also fitted linear and step-level models to determine whether the observed associations differed across levels of need. This design was intended to examine graded substance use outcomes rather than relying only on binary categories, within a framework in which movement away from crisis can represent meaningful progress.

After adjustment, all three assessed domains were associated with better substance use outcomes, but the magnitude of those associations differed. Mental health had the strongest association, with an odds ratio of 2.17 (95% confidence interval [CI], 1.87–2.51). Housing stability was also associated with better outcomes, with an odds ratio of 1.52 (95% CI, 1.34–1.73). Access to health care had a smaller association, producing an odds ratio of 1.23 (95% CI, 1.06–1.43). These estimates describe statistical relationships in the analyzed records; the source does not establish that changes in any of these domains directly caused changes in substance use ratings.

The step-level analysis showed that the associations were not uniform across the five-point scale. The largest differences appeared between the Urgent Need and High Need categories for mental health and housing stability. Access to health care followed a heterogeneous pattern, including a negative association at the lowest step-level comparison despite its positive overall adjusted association. Mental health and housing stability were therefore the most influential domains in the study’s model results, with access to health care playing a more variable role. The authors concluded that step-based, harm reduction-aligned assessment may better capture incremental changes in substance use stability and inform equity-oriented service planning.

The findings should be interpreted within the study’s scope and design. Because the analysis was cross-sectional and used baseline assessments, it cannot establish temporal order or causal effects. The records came from clinician-assigned assessments at a single harm reduction–oriented specialty hospital rather than a population-based sample, limiting direct generalization to other cities, clinical settings or populations. The results also concern the three assessed domains in the available records and do not provide population-wide prevalence estimates or proof that a specific intervention will improve substance use outcomes. The most consistent pattern was an association between mental health, housing stability and graded substance use outcomes, particularly across the two most acute categories of need, while the role of health care access depended on the level of comparison.

Subject of Research: Associations among mental health, housing stability, health care access and graded substance use outcomes in a Toronto clinical setting

Article Title: Mental health, housing stability, and health care access as determinants of substance use outcomes: a step-level analysis in a harm reduction–oriented clinical setting in Toronto, Canada

Article References: Ali, F., Prashad, C. D., Chellew Paternostro, S., Ashcroft, R., Chandrasekera, U., Elton-Marshall, T., McDonald, L., Simons, J., & Ismail, Y. (2026). Mental health, housing stability, and health care access as determinants of substance use outcomes: a step-level analysis in a harm reduction–oriented clinical setting in Toronto, Canada. BMC Public Health. https://doi.org/10.1186/s12889-026-29499-z

Image Credits: AI Generated

DOI: 10.1186/s12889-026-29499-z

Keywords: substance use outcomes, mental health, housing stability, health care access, harm reduction, social determinants, ordered logistic regression, Casey House, Toronto, public health, Mental, health