People with severe mental illness such as schizophrenia or bipolar disorder have a higher risk for substance use, especially cigarette smoking, and protective factors usually associated with lower rates of substance use do not exist in severe mental illness, according to a new study funded by the National Institute on Drug Abuse (NIDA), part of the National Institutes of Health.
Estimates based on past studies suggest that people diagnosed with mood or anxiety disorders are about twice as likely as the general population to also suffer from a substance use disorder. Statistics from the 2012 National Survey on Drug Use and Health indicate close to 8.4 million adults in the United States have both a mental and substance use disorder. However, only 7.9 percent of people receive treatment for both conditions, and 53.7 percent receive no treatment at all, the statistics indicate.
Studies exploring the link between substance use disorders and other mental illnesses have typically not included people with severe psychotic illnesses.
“Drug use impacts many of the same brain circuits that are disrupted in severe mental disorders such as schizophrenia,” said NIDA Director Dr. Nora D. Volkow. “While we cannot always prove a connection or causality, we do know that certain mental disorders are risk factors for subsequent substance use disorders, and vice versa.”
In the current study, 9,142 people diagnosed with schizophrenia, schizoaffective disorder, or bipolar disorder with psychotic features, and 10,195 controls matched to participants according to geographic region, were selected using the Genomic Psychiatry Cohort program. Mental disorder diagnoses were confirmed using the Diagnostic Interview for Psychosis and Affective Disorder (DI-PAD), and controls were screened to verify the absence of schizophrenia or bipolar disorder in themselves or close family members. The DI-PAD was also used for all participants to determine substance use rates.
- Alcohol dependence co-occurs with mental illness more often than most clinicians realize: >20% of those with mental illness also suffer from alcohol abuse or dependence.
- Alcohol dependence, abuse, or misuse can cause or exacerbate Cluster B personality disorders, and alcoholism itself can be mistakenly diagnosed as a personality disorder.
- Treatment of alcohol dependence and a co-occurring mental illness necessitates a coordinated plan which addresses both problems.
Compared to controls, people with severe mental illness were about 4 times more likely to be heavy alcohol users (four or more drinks per day); 3.5 times more likely to use marijuana regularly (21 times per year); and 4.6 times more likely to use other drugs at least 10 times in their lives. The greatest increases were seen with tobacco, with patients with severe mental illness 5.1 times more likely to be daily smokers. This is of concern because smoking is the leading cause of preventable death in the United States.
In addition, certain protective factors often associated with belonging to certain racial or ethnic groups - or being female - did not exist in participants with severe mental illness. “In the general population, women have lower substance use rates than men, and Asian-Americans have lower substance use rates than white Americans, but we do not see these differences among people with severe mental illness,” said Dr. Sarah Hartz, from the Washington University School of Medicine in St. Louis and first author on the study. “We also saw that among young people with severe mental illness, the smoking rates were as high as smoking rates in middle-aged adults, despite success in lowering smoking rates for young people in the general population.”
Previous research has shown that people with schizophrenia have a shorter life expectancy than the general population, and chronic cigarette smoking has been suggested as a major contributing factor to higher morbidity and mortality from malignancy as well as cardiovascular and respiratory diseases. These new findings indicate that the rates of substance use in people with severe psychosis may be underestimated, highlighting the need to improve the understanding of the association between substance use and psychotic disorders so that both conditions can be treated effectively.
For more information on the association between substance abuse and mental illness, go to http://www.drugabuse.gov/publications/comorbidity-addiction-other-mental-illnesses/why-do-drug-use-disorders-often-co-occur-other-mental-illnesses.
This study was funded by NIH, NIDA under DA062380 and DA025733; NIAAA under AA008401; NCATS under RR024992 and RR024994; NCI under CA089392; and NIMH under MH085548 and MH085542.
A common Alcoholics Anonymous (AA) saying is “There is no problem that alcohol cannot make worse.” Of all the problems that alcohol can exacerbate, mental illness is one of the most common, serious, and frequently missed. Patients with mental illness, irrespective of the diagnosis, can face profound consequences when they misuse alcohol.
According to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), the diagnosis of alcohol dependence, abuse, or misuse is no different in the presence of another mental illness. However, when dealing with those suffering from mental illness, the criteria for diagnosing a patient’s problem with alcohol should be quite broad. That is, the depressed individual who only misuses alcohol occasionally should be considered to “have a problem” with alcohol, even if he would not meet strict DSM-IV criteria for alcohol dependence or even abuse.
So when does alcohol worsen a mental disorder and when is it merely incidental? As this review will demonstrate, the answer is that alcohol always plays a part. Alcohol causes some depressive and anxiety syndromes, worsens others, always impairs sleep, and has harmful interactions with psychiatric medications. Thus, a person who drinks any amount of alcohol while receiving psychiatric treatment, especially pharmacologic treatment, should be advised to stop all use of alcohol. Of course, the addicted individual may not be able to stop his or her alcohol use and may need education about the interaction between addiction and mental illness, treatment of the addictive substance use, or even inpatient treatment of the addiction. Cessation of alcohol use is an important clinical goal but will most likely not be achieved overnight.
The cessation of alcohol use does not guarantee the remission of psychiatric symptoms. Nonetheless, discontinuing alcohol use for the psychiatric patient is often necessary, partly to remove an impediment to effective treatment. Mental illnesses often confounds efforts to stop alcohol use: the profoundly anxious person who experiences a quick, short-lived, respite from her anxiety will only reluctantly part with her “medication.” This article reviews the various psychiatric syndromes most commonly linked with alcohol, discusses the relevant research, and recommends some treatment approaches.
NIDA Press Office
About the National Institutes of Health (NIH): NIH, the nation’s medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases.