Prevalence and Co-Occurrence of Substance Use Disorders and Independent Mood and Anxiety Disorders: Results From the National Epidemiologic Survey on Alcohol and Related Conditions

BACKGROUND: Uncertainties exist about the prevalence and comorbidity of substance use disorders and independent mood and anxiety disorders. OBJECTIVE: To present nationally representative data on the prevalence and comorbidity of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM–IV) alcohol and drug use disorders and independent mood and anxiety disorders (including only those that are not substance induced and that are not due to a general medical condition). DESIGN: Face-to-face survey. SETTING: The United States. PARTICIPANTS: Household and group quarters residents. MAIN OUTCOME MEASURES: Prevalence and associations of substance use disorders and independent mood and anxiety disorders. RESULTS: The prevalences of 12-month DSM–IV independent mood and anxiety disorders in the U.S. population were 9.21 percent (95 percent confidence interval [CI], 8.78 percent–9.64 percent) and 11.08 percent (95 percent CI, 10.43 percent–11.73 percent), respectively. The rate of substance use disorders was 9.35 percent (95 percent CI, 8.86 percent–9.84 percent). Only a few individuals with mood or anxiety disorders were classified as having only substance-induced disorders. Associations between most substance use disorders and independent mood and anxiety disorders were positive and significant (p < .05). CONCLUSIONS: Substance use disorders and mood and anxiety disorders that develop independently of intoxication and withdrawal are among the most prevalent psychiatric disorders in the United States. Associations between most substance use disorders and independent mood and anxiety disorders were overwhelmingly positive and significant, suggesting that treatment for a comorbid mood or anxiety disorder should not be withheld from individuals with substance use disorders.