Concurrent Disorders

Concurrent Disorders describes a condition in which a person is experiencing mental illness and utilizes substances. They are also referred to as dual disorders, dual diagnosis (with the exception of the province of Ontario, where this term refers to individuals with a combination of an intellectual disability and mental health disorder), and co-occurring substance use and mental health problems. This term is a general one that refers to a wide range of mental illnesses and addictions. For example, someone with schizophrenia who is addicted to opioidshas a concurrent disorder, as does an individual who suffers from chronic depression and is also an alcoholic. Treatment approaches for each case could be quite different.

It is challenging to determine conclusively how many people have a concurrent disorder because existing studies examine different populations and utilize differing screening tools. It is estimated that people with mental illness are twice as likely compared tothose in the general population to utilize substances. At least 20% of people experiencing mental illness also use substances. Similarly, individuals with an addiction have much higher rates of mental illness (likely three times as high) than people in the general population.

As concurrent disorders include substance use and the addition of various mental health disorders, no particular symptom or group of symptoms present the same for all combinations. According to the Centre for Addiction and Mental Health (CAMH), there are five main groups of concurrent disorders:

  • Substance use with mood and anxiety disorders (eg. depression or panic disorder)
  • Substance use with severe and persistent mental health disorders (eg. schizophrenia or bipolar disorder)
  • Substance use with personality disorders (eg. borderline personality disorder, or problems related to anger, impulsivity or aggression)
  • Substance use with eating disorders (eg. anorexia nervosa or bulimia)
  • Other substance use with mental health disorders (eg.  gambling and sexual disorder)

People with concurrent disorders are frequently misidentified, as diagnosis can be more difficult because one disorder can mimic another. Relapse rates for substance use are higher for people with a concurrent mental disorder, as are the chances that symptoms of mental illness will return for those with a concurrent substance use problem.

It has been suggested that an integrated treatment approach is an effective way to treat concurrent disorders. Such an approach ensures that other areas of the affected individual’s life, such as housing and employment, are being dealt with. This can prevent further relapses and maintain success with treatment plans. Those with concurrent disorders need help and services from several sectors: mental health, addiction, health care, education, and social services. It is essential to integrate mental health services with addiction treatment services as well as the developmental and mental health sectors.

Mental illnesses and substance use disorders are more prevalent among people experiencing homelessness and inmates than among the general population. Their prevalence among these segments of the Canadian population is growing. Improving access to the services and supports these individuals need requires inter-jurisdictional collaboration.