The U.S. Preventive Services Task Force (USPSTF) recommends that clinicians screen adults ages 18 years or older for alcohol misuse and provide persons engaged in risky or hazardous drinking with brief behavioral counseling interventions to reduce alcohol misuse (Grade B recommendations) (U.S. Preventive Services Task Force, 2014).

Substance Use Disorders Prevalence

According to DSM-5, 12-month prevalence of specific substance use disorder among adults is following: (American Psychiatric Association, 2013)

• Alcohol use disorder: 8.5%
• Cannabis use disorder: 1.5%
• Phencyclidines use disorder: 1.3 – 2.9%
• Opioid use disorder: 0.37%
• Sedative, hypnotic or anxiolytic use disorder: 0.2%
• Stimulants use disorder: 0.2%

Alcoholism and major depressive disorder are distinct clinical entities. They are not different expressions of the same underlying condition. Within the general population, substance abuse prevalence ranges from 8% to 21%. In people with major depression, it is about 7.8% (Davis, 2006). However, alcohol-use disorders are under reported in primary care (for example, higher risk drinking 1% males, 0.5% females) in comparison with Opinions survey (8% males, 7% females) (Hawkins, 2007).

Screening for Alcohol and Other Drug Use (CAGE, CAGE-AID, AUDIT, AUDIT-C, DAST-10)

CAGE and CAGE-AID

The CAGE tool questions are sensitive and specific in screening for alcohol dependence. One positive response has a sensitivity of 85% and a specificity of 89%, and two positive responses have a specificity of 96% (Bush, 1987). Additionally, a 2000 systematic review showed that the CAGE questions were superior in detecting alcohol abuse and dependence compared to the AUDIT tool (sensitivity, 43%-94%; specificity, 70-97%) (Fiellin, 2000).

The CAGE-AID questionnaire broadens the CAGE to include other drugs. One or more Yes responses had sensitivity of 79% and specificity of 77% in detecting alcohol abuse and dependence (Brown, 1995). Two or more Yes responses had sensitivity of 70% and specificity of 85% (Brown, 1995). The CAGE tool shows promise in identifying pregnant, low-income women at risk for heavier drug use (Midanik, 1998).

AUDIT and AUDIT-C

The Alcohol Use Disorder Identification Test (AUDIT) is a widely used screening tool that consists of 10 questions; it can be self-administered, or the questions can be read aloud (Babor, 2001). The AUDIT tool questions are most effective in identifying patients with at risk, hazardous or harmful drinking (sensitivity, 51-97%; specificity, 78-96%) (Fiellin, 2000). The AUDIT-C is a modified three-question version of the AUDIT tool.

DAST-10

The Drug Abuse Screening Test (DAST) is a 10-item, yes/no self-report instrument that has been condensed from the 28-item DAST questionnaire. See the following reference for details: Gavin DR, Ross HE, Skinner HA, "Diagnostic validity of the Drug Abuse Screening Test in the assessment of DSM-III drug disorders," Brit J Addiction 1989;84:301-07.

Treatment

The medical literature does not support definitive statements about the best way(s) to treat patients who are diagnosed with both major depression and substance abuse/dependence. Based on the majority of studies reviewed, success in treating dependency on alcohol, cocaine and other abused substances is more likely if accompanying depression is simultaneously treated.

Fewer investigators have looked at whether treating substance abuse is helpful in reducing depression. There is some evidence that patients with major depression that is secondary to their substance abuse may have remission of their depressed mood once the substance abuse is treated. However, it is difficult to separate secondary depression from primary depression that predates or is separate from the substance use.

Additional Resources. A complete discussion of evaluation and treatment for chemical dependency is beyond the scope of this guideline. However, SBIRT (Screening, Brief Intervention, Referral and Treatment) is a process wherein a care coordinator uses motivational interviewing to assist patients who have high-risk drinking behavior. The National Institute on Alcohol Abuse and Alcoholism and other agencies offer tools to guide primary care-based medical treatment of alcohol abuse. For more information, see also the ICSI Healthy Lifestyles guideline and the following online resources by Substance Abuse and Mental Health Services Administration (SAMHSA) and the National Institute on Alcohol Abuse and Alcoholism (NIAAA).

Psychiatric Comorbidity

Bipolar disorder

Be aware of ongoing mental illness diagnosis or other mental health illnesses and comorbidities. Patients with a history of manic (bipolar) symptoms now presenting with major depression may be destabilized if treated only with antidepressant drugs. If a manic or hypomanic episode occurs while treating a patient for depression, change the diagnosis to bipolar affective disorder and treat accordingly (Judd, 2002). Behavioral health involvement is advised with these patients unless a patient has a prior history of successful primary care management.

Generalized anxiety disorder and panic disorder

Depressed patients may present with comorbid panic symptoms and generalized worries. Primary care clinicians should screen for symptoms of these disorders and potential causes. Assess for the following:

• Excessive use of stimulant containing products such as energy drinks or shots and caffeinated beverages
• Presence of medical causes of symptoms:
  - Thyroid disease
  - Cardiac disease
  - Irritable bowel syndrome
  - Migraines
  - Vestibular disorders
  - Respiratory and pulmonary disorders
• Use of medications like psychostimulants
• Use of or withdrawal of substances like cocaine, methamphetamine, THC or alcohol

Other disorders

Major depression may also be associated with other psychiatric problems including personality disorders, psychosis, eating disorders and substance abuse. Patients with these conditions may need specialty care services, and details of treatment are beyond the scope of this guideline.