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What is Complex Mental Illness & Substance Use?

BC Mental Health and Substance Use Services cares for people with the most complex and severe mental illness and substance use challenges in British Columbia. What does this mean?

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Defining complex mental illness and substance use

We are tasked with treating the most ill, most vulnerable people in the province. Our clients' and patients' needs go beyond what most people can access within their local communities, such as appointments with a psychiatrist for a mood disorder like anxiety or depression, or 12-step meetings for addiction.

We use the word "complex" to describe the nature of the mental health and substance use disorders they live with: Their illnesses are very severe, there are significant challenges with treating them, and several other factors often further complicate their illnesses.

What is a concurrent disorder?

One frequent example of the kind of complex illness we treat is a concurrent disorder, which is defined as a combination of a severe mental illness and substance use disorder. Both challenges must be present for this diagnosis. People with a concurrent disorder might have both schizophrenia and an opioid addiction, or post-traumatic stress disorder and an alcohol addiction.

Adding to the complexity of a concurrent disorder is the fact that people with this diagnosis often live with other challenges that can make their illnesses more complicated and their recovery even more challenging:

  • An additional mood or personality disorder that makes a client feel particularly anxious, fearful or paranoid
  • A chronic physical illness
  • A history of poor health or dental care due to social barriers
  • Unstable housing and/or unemployment
  • Stigma

Trauma and mental health and substance use

The majority of our patients and clients have also experienced trauma, including abuse, neglect, sexual assault, or other adverse experiences, including adverse childhood experiences. Research has clearly shown that trauma is often correlated with mental health and substance use — even more so among women.

All of these factors combined mean that treatment for our patients and clients is extremely challenging, requiring comprehensive assessments and diagnoses and expertise from a varied and interdisciplinary team of specialized professionals. Treatment this complex also requires a great deal of time, which is why most of our programs are several months long.

Person-centred, strengths-based approach

We are strong advocates for hope in the face of complex mental illness and substance use challenges. We believe that people, when properly supported, have the strength and resiliency to manage their lives. We also believe that people can recover. We see it every day.

BC Mental Health and Substance Use Services therefore focuses on peoples' strengths rather than solely on their symptoms and problems. We treat people using a whole-person approach, addressing substance use, mental illness, chronic health conditions, triggers, histories of trauma and more within one integrated care plan. Care is evidence-based, which means it is informed by research, and trauma-informed, meaning they work to ensure that people feel safe, secure and supported throughout their time with us.

Learn more

To learn more about our programs for people with complex mental illness and substance use challenges, visit Our Services.

SOURCE: What is Complex Mental Illness & Substance Use? ( )
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