Cannabis use disorder among veterans: Comorbidity and mental health treatment utilization.

Cannabis use disorder (CUD) is the most common illicit substance use disorder in the United States and is related to a range of functional impairment. CUD is associated with comorbid mental health disorders and other substance use disorders, compounding impairment from either type of disorder alone. U.S. military veterans also experience CUD at high rates; however, less is known about comorbidity and its impact on service utilization among veterans. Better understanding of comorbidity in this group is important, given that the Veterans Health Administration is the largest U.S. healthcare provider and is uniquely positioned to potentially address the challenges of comorbid CUD. The current study aimed to examine rates of comorbidity among veterans with CUD and the impact of comorbidity on mental health service utilization. Data were obtained through national Veterans Health Administration administrative and clinical records from 2010 to 2016. 79.1% of veterans with CUD were also diagnosed with a mental health disorder, and 76.8% were diagnosed with another substance use disorder. Overall, veterans with CUD and a comorbid mental health disorder used more individual psychotherapy than those with CUD alone. These findings suggest that CUD among veterans is rarely diagnosed independent of other disorders and that comorbidity is associated with greater mental healthcare utilization. Improved screening for CUD and integration of its treatment within current models of care may be important to consider in large healthcare systems.