Substance use and abuse among patients with comorbid dysthymia and substance disorder.

This study determines the substance use and abuse patterns among patients with comorbid substance-related disorder (SRD) and dysthymia in SRD-dysthymia as compared with patients with SRD only. Differences in use and abuse patterns could be useful for (a) understanding motivations for use, such as self-treatment, and (b) assisting clinicians to identify cases of dysthymia among SRD patients. Retrospective and current data were obtained regarding history of substance use and current SRD diagnoses. Two university medical centers with alcohol-drug programs located within departments of psychiatry were the settings. A total of 642 patients was assessed. of whom 39 had SRD-dysthymia and 308 had SRD only. Data on past usc were collected by a research associate using a questionnaire. Current SRD and dysthymia diagnoses were made by psychiatrists specializing in addiction. The patients with SRD-dysthymia and SRD only did not differ with regard to use of alcohol, tobacco, and benzodiazepines. The patients with SRD-dysthymia started caffeine use at an earlier age, had shorter "use careers" of cocaine, amphetamines, and opiates, and had fewer days of cocaine and cannabis use in the last year. They also had a lower rate of cannabis abuse/dependence. This study indicated that patients with dysthymia and SRD have exposure to most substances of abuse that is comparable to patients with SRD only. However, they selectively use certain substances less often than patients with SRD only. Early use of caffeine may reflect self-treatment for depressive symptoms among patients with SRD-dysthymia.