The relationship between anxiety and substance use disorders among individuals with severe affective disorders

We sought to determine the association between anxiety disorders and substance use disorders among patients with severe affective disorders in a community-based outpatient treatment program. Two hundred sixty participants in a supported socialization program were assessed using the Structured Clinical Interview for DSM-III-R (SCID). Multivariate logistic regression analyses were used to determine the relationship between anxiety disorders and alcohol and substance use disorders among patients with severe and persistent affective disorders (i.e., major depression and bipolar disorder). Among patients with severe and persistent affective disorders, cocaine (odds ratio [OR] = 5.9 [1.4, 24.6]), stimulant (OR = 5.1 [1.2, 20.9]), sedative (OR = 5.4 [1.2, 24.7]), and opioid use disorders (OR = 13.9 [1.4, 138.7]) were significantly more common among those with, compared with those without, anxiety disorders. This association persisted after adjusting for differences in sociodemographic characteristics and comorbid psychotic disorders. Significant associations between panic attacks, social phobia, specific phobia, and obsessive-compulsive disorder (OCD) and specific substance use disorders were also evident. These findings are consistent with and extend previous results by documenting an association between anxiety disorders and substance use disorders, independent of comorbid psychotic disorders among patients in a outpatient psychiatric rehabilitation program. These data highlight the prevalence of comorbid anxiety disorders, a potentially undetected and therefore undertreated problem, among patients with severe affective disorders and substance use comorbidity. Future work is needed to determine the nature of this association and to determine whether treatment of one prevents onset of the other.