Results of a screening survey for co-morbid substance misuse amongst patients in treatment for psychotic disorders: prevalence and service needs in an inner London borough

Abstract

Background: There is great concern in the UK, and other countries, about the clinical management of psychosis and substance misuse co-morbidity. However, relatively little is known about the UK prevalence and management of co-morbidity. Method: We implemented a screening survey of patients who were in treatment with an inner London adult mental health service and measured the prevalence of substance misuse amongst 851 psychotic patients. Caseworkers reported substance misuse and assessed clinical management arrangements. Results: Current prevalence of substance misuse was 24.4 % (95% CI: 21.3–27.1). Rates of co-morbidity were higher in males (31 % vs 16 %, χ² 1df=26.0, P < 0.001) and patients over 51 (χ² 3df=50.1, P < 0.001). Adjusted odds of co-morbidity in patients under 51 were 0.19 (95 % CI: 0.10–0.34) and 0.47 for females (95 % CI: 0.32–0.69). Substance misuse interventions were provided to 20 % of co-morbid patients – Only 5 % were compliant. Conclusions: The findings suggest substance misuse may be highly prevalent amongst psychotic patients. Most co-morbid patients do not receive appropriate treatment. The development of evidence-based interventions should be a priority.