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People with mental illness and a history of homelessness more likely to use healthcare services


A new study from ICES and Unity Health Toronto finds that the rates of inpatient, emergency and physician visits were higher for homeless participants with a mental illness compared to a general cohort of homeless adults.

The research, published in Health Services Insights, explored factors associated with healthcare encounters among adults experiencing homelessness in Ontario.

Homeless individuals can have elevated healthcare needs, and are more likely to be hospitalized, visit the emergency department (ED), and see a primary care physician compared to low-income populations. However, healthcare use is not the same for all groups who experience homelessness.

“There is a subgroup of people experiencing homelessness who use acute healthcare services more frequently,” says Kathryn Wiens, a PhD graduate from the University of Toronto. “Knowing this, we can identify risk factors and health behaviours that are associated with higher use and work to develop effective interventions within healthcare settings to meet the individual needs of people experiencing homelessness.”

Survey data from two cohort studies were linked to ICES administrative health records for a general cohort of homeless adults and a cohort of homeless adults with mental illness. The researchers found that during the one-year follow-up:

  • Compared to the general homeless cohort, people in the cohort with a mental illness had higher rates of inpatient (27% vs 14%), emergency (63% vs 53%), and physician services (90% vs 76%).
  • Black participants were less likely to visit a primary care physician than white participants and were also less likely to use ED services or be admitted to a non-psychiatric inpatient unit.
  • Other factors, such as problematic alcohol and drug use, criminal behaviour, and victimization were all associated with higher rates of ED use in both cohorts.

These findings underscore the factors related to elevated healthcare use, such as mental illness and substance use, and can inform interventions that leverage the ED as the point of contact. Importantly, interventions need to take a trauma-informed and layered approach to care to reduce the risk of re-traumatization. For those using less services, alternative approaches may be needed.

“There are many reasons why people from racialized groups may not access healthcare services,” says Stephen Hwang, senior adjunct scientist at ICES and director of MAP Centre for Urban Health Solutions at St Michael’s Hospital, a site of Unity Health Toronto. “While the hospital can be a valuable place to identify and support people experiencing homelessness, we must be careful not to prioritize housing and support interventions based on prior high use of healthcare services, as this can perpetuate systemic racism.”

One limitation to this study is that participants from the two cohorts were recruited from shelters, hospitals, and meal programs, and they needed to consent to have their data linked with administrative records using a validated Ontario healthcare number. Therefore, the findings may not be representative of people who are not currently using these services, or who aren’t eligible for provincial health coverage.

The study, “Determinants of hospital use and physician services among adults with a history of homelessness,” was published in Health Services Insights.

Author block: Wiens K, Rosella R, Kurdyak P, Chen S, Aubry T, Stergiopoulos V, Hwang S.

ICES is an independent, non-profit research institute that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy. In October 2018, the institute formerly known as the Institute for Clinical Evaluative Sciences formally adopted the initialism ICES as its official name. For the latest ICES news, follow us on Twitter: @ICESOntario

About St. Michael's

St. Michael’s Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future healthcare professionals in more than 27 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, care of the homeless and global health are among the Hospital’s recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Centre, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael’s Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.

About Unity Health Toronto

Unity Health Toronto, comprised of St. Joseph’s Health Centre, St. Michael’s Hospital and Providence Healthcare, works to advance the health of everyone in our urban communities and beyond. Our health network serves patients, residents and clients across the full spectrum of care, spanning primary care, secondary community care, tertiary and quaternary care services to post-acute through rehabilitation, palliative care and long-term care, while investing in world-class research and education. For more information, visit www.unityhealth.to.


Misty Pratt
Senior Communications Officer, ICES
[email protected]

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