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Co-occurring vs. Co-morbidity Disorders

Understanding diagnosis’ can be overwhelming – and even more overwhelming if you are given one of these. Co-occurring disorders are clinical conditions affecting millions of people around the world, but what, exactly, does the term mean?

Many times, co-occurring disorders refer to individuals with both a mental health disorder and a substance use disorder coexistence. But individuals with both physical and mental conditions have co-morbidity. Comorbidity means you have more than one illness at once. Some conditions have common underlying causes or risk factors, while some comorbidities are directly caused by another condition, its symptoms, or its treatments. Sometimes, conditions are comorbid by coincidence. These disorders affect one person, at the same time, and the effect may vary treatment needs. The term co-occurring disorder is also used interchangeably with dual diagnosis.

According to the Substance Abuse and Mental Health Services Administration (SAMHSA) 2019 National Survey on Drug Use and Health, nearly 50% of individuals with a serious mental illness (SMI) reported engaging in drug or alcohol abuse. Co-occurring disorders can be one mental health disorder and one substance use disorder or involve multiple addictive and psychiatric conditions at once. For example, many people diagnosed with depression will battle both an alcohol use disorder and a painkiller addiction. Those struggling with Post Traumatic Stress Disorder (PTSD) may also wrestle with depression and a substance abuse problem.

While some instances of co-occurring disorders may be more frequent than others, any combination of addiction and mental illness is a “co-occurring disorder.” Examples of common co-occurring disorders include:

  1. Depression and alcohol addiction

  2. Eating disorders and cocaine addiction

  3. Post-traumatic stress disorder and heroin addiction

  4. Anxiety and prescription drug addiction

  5. ADHD and marijuana addiction

Co-occurring disorders are common, recurrent, and often very serious conditions. However, they are also very treatable, and many people do recover with proper treatment.

How Common are Co-Occurring Disorders?

Today, about eight million Americans battle co-occurring disorders. SAMHSA noted co-occurring can affect people of all ages and from all walks of life. Those who battle substance addiction are twice as likely to be diagnosed with a mental health issue.

What Causes Co-Occurring Disorders?

With, co-occurring disorders, either condition substance use, or mental health disorder can develop first. Oftentimes, people struggling with a mental illness will use drugs or alcohol to try and cope with their symptoms (self-medication). In other cases, people have used drugs or alcohol for some time, which then triggered or aggravated psychological problems. Studies show that certain drugs, or long-term substance use, can exacerbate the symptoms of mental illness.

The following risk factors increase a person’s vulnerability to developing a co-occurring disorder:

  1. Any mental illness

  2. Recurrent substance abuse

  3. Lack of appropriate treatment for either of the above

  4. A history of trauma or a traumatic life event

  5. Genetic or family history of mental health disorders and/or addiction

Substance use by teens can have a big impact on their health and well-being. Living with mental illness or a mental health condition can put individuals at a higher risk of drug and alcohol addiction. According to the Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC):

  1. By 12th grade, about two-thirds of students have tried alcohol.

  2. About half of 9th to 12th-grade students reported having used marijuana.

  3. About 40% of 9th to 12th-grade students reported having tried cigarettes.

  4. Among 12th graders, 20% reported using prescription medicine without a prescription.

Risk of substance use

  1. Affects the growth and development of teens, especially brain development.

  2. Occur more frequently with other risky behaviors, such as unprotected sex and dangerous driving.

  3. Contribute to the development of adult health problems, such as heart disease, high blood pressure, and sleep disorders. Which then leads an individual to have co-occurring and co-morbidity disorders.

Finally, the earlier teens start using substances, the greater their chances of continuing to use substances and developing substance use problems later in life. When teens begin drinking at an early age, they increase the chance of becoming addicted to or continuing to abuse substances later in life.

What is co-morbidity?

Comorbidities sometimes interact with each other, but they can also exist entirely separately. Some conditions may raise your risk of developing others or may commonly occur together. For example, a heart attack often occurs with stroke or vascular disease. Chronic kidney disease may occur with hypertension and anemia. Comorbidities are often chronic conditions and can include physical or mental health. It’s possible to have many comorbidities at the same time. For example, a person could have depression, arthritis, diabetes, and high blood pressure.

How Common are Co-morbidity Disorders?

It’s not uncommon for people to be diagnosed with two disorders or conditions at once. Comorbidity in mental illness can include a situation where a person receives a medical diagnosis that is followed by the diagnosis of a mental disorder or vice versa, or it can involve the diagnosis of a mental disorder that is followed by the diagnosis of another mental disorder. Furthermore, in the U.S. National Comorbidity Survey, 51% of patients with a diagnosis of major depression also had at least one anxiety disorder. Only 26% of them had no other mental health condition.

What Causes Co-morbidity Disorders?

Healthcare professionals can play a role in preventing comorbidity. For example, if a social anxiety disorder is left untreated for a long period of time, a person may also develop depression and/or substance abuse in response to the anxiety symptoms. Therefore, prompt diagnosis and treatment of one condition may prevent the development of comorbidities. At a broader level, coordination between primary doctors and mental health professionals is key to preventing comorbid conditions. If you’ve been diagnosed with a physical and/or mental health condition, keep good records of the care that you receive from various professionals, so that each can be aware of the various treatments you are receiving.

The past years have brought many challenges: for our frontline workers, providing care in difficult circumstances, going to work fearful of bringing COVID-19 home with them; for our kids, adapting to taking classes from home, with little contact with teachers and friends, and anxious about their futures; for families whose livelihoods were threatened; for the vast number of people caught in poverty or in fragile humanitarian settings with extremely limited protection from COVID-19; and for people with mental health conditions, many experiencing even greater social isolation than before.

If you or a loved one needs our help, please reach out to us at For other statewide resources (food banks, housing, financial assistance, internet, etc.), visit:


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