Health service use among persons with comorbid bipolar and substance use disorders.

OBJECTIVE: This study tested the hypothesis that patients with comorbid bipolar and substance use disorders use health services to a greater extent than patients with either bipolar or substance use disorder alone.
METHODS: A retrospective chart review was conducted among patients who used health services at the Ralph H. Johnson Department of Veterans Affairs medical center in Charleston, South Carolina, and had bipolar disorder alone, substance use disorder alone, and comorbid bipolar and substance use disorders. Patients with a psychiatric admission between 1999 and 2003 were included in the study. Information was collected on the use of health services one year before and including the index admission.
RESULTS: The records of 106 eligible patients were examined for this study: 18 had bipolar disorder alone, 39 had substance use disorder alone, and 49 had both bipolar and substance use disorders. Compared with the other two groups, the group with comorbid bipolar and substance use disorders was significantly more likely to be suicidal. Compared with the group with bipolar disorder alone, the group with comorbid disorders had significantly fewer outpatient psychiatric visits and tended to have shorter psychiatric hospitalizations. Among patients with an alcohol use disorder, those who also had bipolar disorder were significantly less likely than those with an alcohol use disorder alone to have had an alcohol-related seizure. Patients with comorbid bipolar and substance use disorders were significantly less likely than those with substance use disorder alone to be referred for intensive substance abuse treatment, even though both groups were equally likely to enter and complete treatment when they were referred.
CONCLUSIONS: Despite significant functional impairment among patients with comorbid bipolar and substance use disorders, they had significantly fewer psychiatric outpatient visits than those with bipolar disorder alone and were referred for intensive substance abuse treatment significantly less often than those with substance use disorder alone.