National Rates Of Co-occurring Substance Use And Mental Disorders Call For Better Service Integration

Two studies published in the December issue of the Canadian Journal of Psychiatry have found that multilevel integration is needed for mental health and substance use services to adequately address the needs of people diagnosed with co-occurring disorders. Both studies explored the prevalence of concurrent disorders, first at the provincial level among people served by the community mental health system, and then at the national level among the general population. This new research highlights the need for system-wide planning and improved integration of the mental health and addictions systems.

In the study titled, Prevalence and Profile of People with Co-occurring Mental and Substance Use Disorders Within a Comprehensive Mental Health System, Dr. Brian Rush, Senior Scientist at the Centre for Addiction and Mental Health (CAMH) and Principal Investigator on both studies found that mental health and substance use disorders co-occur in approximately 20 percent - or one in five – of people treated for mental disorders in Ontario's hospitals and mental health clinics.

"We found that co-occurring disorders were highest in selected sub-groups, for example, among younger adults (55%), people receiving specialty inpatient care (28%), and those with personality disorders (34%). It is important that risk management strategies be included in treatment and support models for clients," says Dr. Rush. "We also found that across all levels of care, having a co-occurring disorder was strongly associated with antisocial and challenging behaviour, legal involvement, and risk of suicide or self-harm."

In the second study, Prevalence of Co-occurring Substance Use and Other Mental Disorders in the Canadian Population, which looked at concurrent disorders at the national level, Dr. Rush found that almost two per cent of Canadians—or 435,000 adults—have both a mental and a substance use disorder. About 20% of people with a mental disorder had a co-occurring substance use problem. The findings underscore the need for cooperation between mental health and substance use services at the provincial, territorial, and national levels.

The first to measure the national prevalence of the co-occurrence of certain psychiatric disorders and substance use problems in Canada, the study found that, relative to national estimates, the rate of co-occurring disorders was found to be highest in British Columbia and lowest in Quebec.

The data places Canadian rates at the lower end of the international range. However, Dr. Rush notes that the problem may be much larger than the numbers indicate as several types of mental disorders and certain populations known to be at high risk for co-occurring disorders—homeless, institutionalized, and Aboriginal people, for example—were not included in Statistics Canada's 2002 Canadian Community Health Survey: Mental Health and Well-Being, on which the authors based their analysis.

The populations affected by co-occurring disorders are diverse, and each person has a unique diagnostic profile and unique strengths and needs, speaking to the importance of different models of integrated services and support. The research concludes that a targeted response to more integrated services is needed, including working with hospital and community-based services, and with a focus on integrated training.

"Identifying individuals who need help with both problems is the first step in providing tailored mental health treatment and support programs," says Dr. Rush. "One of the issues is that clinicians specialized in either addiction or mental health may not be able to recognize the co-occurring disorder(s) and the client will not get a proper diagnosis and treatment and support plan."