Co-Occurring Disorders: Substance Use and Mental Health Disorders

What Are Co-Occurring Disorders?

When a person has a mental health disorder (such as PTSD, anxiety, or depression) and a substance use disorder, it’s known as a comorbidity or co-occurring disorders.^1,2,3

If you or a loved one are struggling with co-occurring disorders, you may already understand the challenges associated with both conditions.

To be diagnosed with co-occurring disorders, an individual needs to be evaluated and diagnosed with each disorder independently to ensure they aren’t experiencing effects and symptoms from just one disorder.³

Types of Co-Occurring Disorders

Any mental health disorder can occur with a SUD, but the most commonly occurring disorders include:^3,6

• Anxiety disorders (particularly generalized anxiety disorder, social anxiety disorder, and panic disorder).
• Depressive disorders (particularly major depressive disorder and persistent depressive disorder).
• Post-traumatic stress disorder (PTSD).
• Attention-deficit/hyperactivity disorder (ADHD).
• Bipolar disorder.
• Schizophrenia and other psychotic disorders.
• Personality disorders (particularly borderline personality disorder or antisocial personality disorder).

Risk Factors for Co-Occurring Disorders

Risk factors are various biological, psychological, familial, or other social characteristics that, when present, may increase the likelihood of a person developing SUDs or mental health disorders.⁸ Many mental health disorders and SUDs have common risk factors, which include:⁹

• Genetics. Around 40 to 60% of the development of a SUD may be related to genetics. SUDs and mental illness are heritable, meaning a person is at increased risk should a parent or family member have one condition or co-occurring disorders.
• Life experiences. Childhood trauma, extraordinary stress, and drug use at an early age can lead to increased risk for SUDs and mental health disorders.
• Neurochemicals. Neurochemicals such as dopamine and GABA, as well as the parts of the brain involved in reward, decision-making, and emotions, play a role in SUDs and mental health disorders.

Treatment for Co-Occurring Disorders

Treating both disorders concurrently in an integrated treatment approach is the standard of care for treating co-occurring substance use disorders and mental health disorders.¹⁰ In several studies, the integrated treatment approach consistently resulted in better outcomes than treating each disorder separately.¹¹

Many of the approaches used in the treatment of co-occurring disorders involve some form of behavioral therapy or psychotherapy, along with strategies like education and employment skills to improve overall functioning and keep people motivated to stay in treatment.¹¹