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Substantial differences in healthcare use exist between heavy users of mental healthcare and other heavy users of care


While a small number of people account for a disproportionately large portion of health services use, heavy users of mental healthcare have substantially different patterns of healthcare use than other heavy users of healthcare, according to new research by the Centre for Addiction and Mental Health (CAMH) and the Institute for Clinical Evaluative Sciences (ICES).

The study published today in the January issue of Health Affairs  is one of the first to look at heavy users of mental healthcare specifically – most studies to date have focused on all heavy users.

The study found the average cost of health services used by heavy users of mental healthcare was more than 30 per cent greater than for other heavy users of healthcare. Mental health services, including psychiatric hospitalizations and visits to a physician or a psychiatrist, made up the largest portion (about 88 per cent) of the total cost, and services not related to mental health accounted for the remaining 12 per cent.

“Heavy users of mental healthcare have complex needs, and it’s crucial to address their needs through an integrated, multidisciplinary approach,” says Dr. Claire de Oliveira, scientist and health economist in social and epidemiological research at CAMH, and lead author on the paper.

Using administrative healthcare data collected by ICES, the researchers examined healthcare use by people defined as heavy users based on the costs of the services they used – also referred to as high-cost users. The study looked at nearly one million high-cost healthcare users age 18 years or older in Ontario in 2012. Five per cent – 51,457 people – were considered to be high-cost mental healthcare users, defined as people for whom costs for mental health services were at least 50 per cent of their total healthcare costs.

Understanding which services they use can point to where improvements might occur, both in the delivery of services and in individuals’ wellbeing.

Different population characteristics, and high rates of hospitalization

Heavy users of mental healthcare were younger relative to other high-cost users, and most came from lower-income urban neighbourhoods. People age 18 to 49 made up 58 per cent of heavy users of mental healthcare and only 24 per cent of other high-cost users. Heavy users of mental healthcare also tended to be more evenly split among men and women – 49 per cent were males and 51 per cent were females – versus other heavy users (42 per cent males and 58 per cent females). Other high-cost users were more likely to have chronic diseases, primarily circulatory and digestive illnesses.

About 64 per cent of heavy users of mental healthcare had at least one psychiatric hospitalization in 2012. More than 90 per cent had at least one visit to a doctor for mental healthcare and one or more visits for other healthcare.

The researchers note that other studies have shown that people who have psychiatric hospitalizations, particularly people with severe mental illnesses such as schizophrenia, have high rates of hospital readmission and low rates of physician visits after they are discharged from a psychiatric hospital stay.

“Our research shows that heavy users of mental healthcare have substantially different patterns of healthcare use than other high-costs healthcare users, representing a different patient population,” says Dr. de Oliveira. “Their needs must be considered separately when looking to improve the quality of care for heavy users of healthcare in general.”

Opportunity for early prevention

As a next step, the researchers are developing a predictive model to identify mental healthcare users at highest risk of future hospitalization. “If we can identify individuals at risk before they become high-cost users of mental healthcare, this may present an opportunity to provide earlier preventive healthcare and social services, such as high-support housing units,” says Dr. de Oliveira.

"Patients with high mental health costs incur over 30 percent more costs than other high-cost patients" was published today in the journal Health Affairs.

Author block: Claire de Oliveira, Joyce Cheng, Simone Vigod, Jurgen Rehm, Paul Kurdyak.

The Centre for Addiction and Mental Health (CAMH) is Canada's largest mental health and addiction teaching hospital and a world leading research centre in this field. CAMH combines clinical care, research, education, policy development and health promotion to help transform the lives of people affected by mental illness and addiction. CAMH is fully affiliated with the University of Toronto, and is a Pan American Health Organization/World Health Organization Collaborating Centre. For more information, please visit camh.ca or follow @CAMHnews on Twitter.

The Institute for Clinical Evaluative Sciences (ICES) is an independent, non-profit organization 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. For the latest ICES news, follow us on Twitter: @ICESOntario


  • Anita Dubey
  • Centre for Addiction and Mental Health (CAMH)
  • (416) 535-8501 ext. 34932
  • [email protected]
  • Kathleen Sandusky
  • Media Advisor, ICES
  • [email protected]
  • (o) 416-480-4780 or (c) 416-434-7763

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