Self-medication with alcohol or drugs for mood and anxiety disorders: A narrative review of the epidemiological literature

Background: The comorbidity of mood and anxiety disorders (MD and AD) with substance use disorders (SUD) is common. One explanation for this comorbidity is the self-medication hypothesis, which posits that individuals with MD or AD use substances to cope with the difficult symptoms associated with the disorder. Over time, self-medication (SM) can develop into an independent SUD. This narrative review will present the prevalence and correlates of SM with alcohol and/or drugs for MD and AD and the relationship between SM and subsequent SUD using both cross-sectional and longitudinal epidemiological data. Methods: Scopus and PsycINFO were searched from January 1997 to April 2018 to identify original research articles that examined the prevalence and correlates of SM and the temporal relationship between MD/AD and SUD in the general population (n=22). Results: The prevalence of SM with alcohol and/or drugs among those with MD or AD ranged from 21.9% to 24.1%. Male sex, younger age, being separated, divorced or widowed, and being Caucasian were characteristics associated with higher proportions of respondents endorsing SM with alcohol/drugs for MD and AD. Longitudinal data supports the temporal onset of primary MD/AD and secondary SUD among those who self-report SM. Conclusion: Providing and promoting alternate coping strategies for those with MD/AD may reduce SM, the development of SUD, and the comorbidity of MD/AD with SUD. The concurrent treatment of MD/AD and substance use is the current gold standard model of care, and the results of this review support its use.