Dual Diagnosis occurs when a person has an alcohol or substance abuse problem and a mental health disorder. Also called comorbidity, the instances of having two or more co-occurring disorders is far more common than one might believe. It’s estimated that nearly 50 percent of all persons diagnosed with mental health disorders have a substance abuse problem. Similarly, a high percentage of individuals who abuse alcohol or drugs (37 and 53 percent, respectively) also have a mental illness, according to the National Alliance on Mental Illness.
Mental Illness and Substance Abuse Facts
Individuals experiencing co-occurring illness of two or more conditions may often feel at the mercy of their disorders. Some can be debilitating, leaving a person feeling weak, alone and helpless. Others can produce what appear to be hallucinations and delusions. In addition to the statistics provided above, epidemiological data suggests strong links between drugs, alcohol, and mental illness as well:
- Lifetime use rates of alcohol are estimated at 66 percent, while drugs are slightly lower at an estimated 30 percent.
- Nearly 30 percent of individuals with diagnosed mental health disorders also had substance abuse problems.
- Approximately 36.6 percent of persons with alcohol abuse disorders and 53.1 percent with substance abuse disorders also had a mental illness.
- Of the 9.9 percent of the population suffering from lifetime major depression, nearly 20 percent had a co-occurring drug problem.
- People with bipolar disorder are five times more likely to have a substance abuse or alcohol problem, while schizophrenics are four times more likely.
- Common mental health disorders relative to substance use include depression, anxiety, and attention deficit hyperactivity disorder (ADHD).
Consequences of Comorbidity and Barriers to Treatment
Untreated comorbidity can result in a myriad of complications for the individual. Even if treated, comorbid persons often experience more severe symptoms, impaired social functioning, higher instances of physically comorbid conditions like kidney or liver disease, and persistent thoughts of suicide.
Biomed Central Psychiatry notes that comorbid conditions have traditionally been treated as two separate illnesses, leaving one to be treated subsequent to another. Newer research studies show that integrated therapy is a preferred method of treatment for Dual Diagnosis, as opposed to sequential or simultaneous treatment. Unfortunately, comorbid individuals still face difficulties in treatment through inadequate care or inaccessibility to proper care, longer diagnosis times, and less compliance during treatment.
Understanding Which Came First: The Substance Use or the Mental Illness?
One of the more frequent relationships noted in comorbid conditions is the correlation of substance abuse inducing mental illness. High instances of this include examples like alcohol-induced depression, stimulant-induced manic disorder, or cocaine-induced psychotic disorder as noted by Columbia University.
Substance-induced mental illness
This type of diagnosis can be hard to pinpoint because it requires the individual to be abstinent for a certain length of time. Because many drugs can project symptoms that appear to mimic those of mental illnesses, abstinence for a period is key. Although, this can present some problems as one doesn’t want to wait too long to treat the persistent symptoms of a possibly severe mental illness.
The DSM-IV defines substance-induced disorders as “the direct physiological consequence of substance intoxication or withdrawal, medication use, or toxin exposure,” meaning it develops as a result of substance use or withdrawal from substances. To understand more about the underlying mental illness and substance problem, physicians must evaluate the person’s history with drugs and/or mental illness, laboratory results like blood tests or urinalysis, and a physical examination. In order for a substance-induced disorder to be considered valid or legitimate, the physical symptoms of the disorder must be present yet not all criteria must be met. So, for example, if a person with alcohol-induced depression exhibited signs of fatigue and overwhelming sadness but did not seem to have a low sense of self-worth, a diagnosis may still be made.
Substance use secondary to mental illness
An individual may self-medicate with drugs or alcohol to alleviate the symptoms of a mental illness, should the symptoms be difficult to manage. In this case, the mental illness may be considered the primary disorder as opposed to the substance abuse. This is more common in individuals who may be too poor to afford the high costs of prescription drugs and other treatment. In an article noted by the National Institutes of Health, approximately 20 percent of those suffering from post-traumatic stress disorder (PTSD) self-medicated by using drugs or alcohol to relieve the anxiety and panic associated with the illness.
Another method of “self-medication” is when individuals use drugs to enhance the symptoms of the mental illness. This might be evident in people with manic disorders using stimulants to increase alertness or focus, for example.
Independent mental illness and substance abuse
In this situation, both the mental health disorder and the drug or alcohol use develop separately from one another. After abstinence from drugs, a mental illness may be deemed independent of substance use if the symptoms still persist and the individual meets the criteria for the mental health condition.
How to Diagnose and Assess Co-Occurring Illnesses
Assessing and treating a comorbid condition can be especially difficult due to the co-occurring nature of the disorders. One can often proliferate the other or, in some cases, both the substance abuse and the mental illness can occur separately from one another. Determining which illness is primary to the other can be problematic and troublesome.
After a period of detoxification, physicians may have a better chance of diagnosing a patient with one of the above types of substance-related comorbidities. Many substance use disorders have symptoms that will rapidly decline after use discontinues, making a proper diagnosis more feasible.
So what then? After substance use stops, how to physicians know how to diagnose a mental health disorder? For that, a variety of illness-specific models have been established to help doctors, psychiatrists, and physicians better determine what disorders are present within an individual.
Perhaps one of the most widely used interview models for clinical assessment is the PRISM-IV. The PRISM-IV stands for Psychiatric Research Interview for Substance and Mental Disorders, and is a structured set of questions that help the interviewer assess mental illness and its relation to substance abuse. With a structured set of interview questions and measures for illness severity, an interviewer can better identify one or more of many mental illnesses. Over 10 major mental health disorders are targeted in this questionnaire including personality disorders, PTSD, obsessive-compulsive disorder (OCD), panic disorder, social phobias, specific phobias, major depression, manic depression, and schizophrenia. Typically, questions relating to substance use precede those relating to mental illness so as to best serve as a benchmark for possible mental health disorders, and to understand how the two relate in an individual.
Other assessment models include the Young Mania Rating Scale (YMRS) for manic disorders and bipolar disorder, the Inventory of Depressive Symptoms (IDS), the Montgomery Asberg Depression Rating Scale (MADRS), the Structured Clinical Interview for DSM-IV for Axis II personality disorders (SCID-II), and the Angst Hypomania Check List (AHCL) that assesses hyperactivity and hypomania (useful for bipolar disorder evaluation).
These targeted assessments, along with detoxification, can dramatically help a physician determine what mental illness or illnesses remain comorbid with a substance use problem. While a 100 percent accurate diagnosis may be difficult all the time, achieving the best diagnosis possible is the goal.
The right facility can help you or your loved one obtain a diagnosis for co-occurring disorders and make a recommended treatment plan that is right for you. At FRN, we specialize in treatment of Dual Diagnosis conditions, and we’d like to help you. Call us and we can help you figure out what treatment options match your life and get you started on a recovery plan soon.
Further Reading About Testing and Assessments for Comorbidity
- Cognitive Testing
- Diagnosing Illness Through Neuroimaging Scans
- Diagnosing Patients Using Electroencephalography
- Neuropsychological Testing
- Personality Assessments
- Psychological Testing
- Testing for Dual Diagnosis
- Using Magnetic Resonance Imaging (MRI) to Diagnose Mental Illness
- Vocational Testing
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David W. Newton is a board certified pharmacist and also has been a board member for boards of examiners for the National Association of Boards of Pharmacy since 1983. His areas of expertise are primarily pharmaceuticals as well as cannabinoids. You can read an article about his expertise in CBD on the National Library of Medicine.
Reviewed by: Kim Chin and Marian Newton