Self-medication of mood disorders with alcohol and drugs in the National Epidemiologic Survey on Alcohol and Related Conditions

Background: Using alcohol or drugs to reduce emotional distress (self-medication) has been proposed as an explanation for the high comorbidity rates between anxiety and substance use disorders. Self-medication has been minimally studied in mood disorders despite equally high rates of alcohol and drug use. Methods: Data came from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), a large (n=43,093, age 18 years and older) nationally representative survey of mental illness in community-dwelling adults. Prevalence rates of self-medication were determined for DSM-IV mood disorders: dysthymia, major depressive disorder, bipolar I disorder, and bipolar II disorder. Multiple logistic regression generated odds ratios for the association between each category of self-medication and anxiety and personality disorders. Results: Almost one-quarter of individuals with mood disorders (24.1%) used alcohol or drugs to relieve symptoms. The highest prevalence of self-medication was seen in bipolar I disorder (41.0%). Men were more than twice as likely as women to engage in self-medication (Adjusted Odds Ratio=2.18; 95% Confidence Interval 1.90-2.49). After controlling for the effects of substance use disorders, self-medication was associated with higher odds of comorbid anxiety and personality disorders when compared to individuals who did not self-medicate. Limitations: Cross-sectional design. Conclusions: The use of alcohol and drugs to relieve affective symptoms is common among individuals with mood disorders in the general population, yet is associated with substantial psychiatric comorbidity. These findings may help clinicians identify a subgroup of people with mood disorders who suffer from a higher mental illness burden. (C) 2008 Elsevier B.V. All rights reserved.