Objective: The current study examined anxiety in people with substance use disorder (SUD) and a psychotic disorder. It is hypothesised that: anxiety disorders (AD) would be highly prevalent (greater than 20%) in people identified as having SUD and psychotic disorders; those with comorbid AD would fair worse than those without, on measures of quality of life, severity of substance dependence, locus of control, suicidality and psychotic symptoms; and, the presence of such anxiety disorder symptomatology would be under-detected by their mental health case managers.
Method: Outpatients with co-occurring substance use disorder and psychosis were interviewed to collect data about their diagnosis, depressive and psychotic symptoms, severity of dependence on substances, quality of life and locus of control. Participants' case managers made blind ratings of the presence and severity of participants' anxiety.
Results: Fifty eight percent of participants had at least one anxiety disorder. Of these, 56% - 70% had case managers who had identified them as having an anxiety problem. The occurrence of anxiety disorder was associated with more external locus of control, greater intensity of suicidal thinking, worse psychotic symptoms, lower quality of life and greater severity of dependence on substances.
Conclusion: This research suggests anxiety in people with substance use disorder and psychosis is highly prevalent, is associated with poorer outcomes, and is under detected by case managers. Further examination of this issue may lead to important advances in the treatment and prognosis of people with substance use disorder and psychosis.