Identifying co-occurring substance use disorders in community mental health centres. Tailored approaches are needed

Background: Increasing evidence shows that substance use disorders (SUD) and psychiatric illness co-occur, and that this co-morbidity renders treatment more difficult and results in greater use of health services. Thus, clinical routines to identify SUD amongst patients in mental healthcare should have high priority in order to provide optimal treatment. Aim: In this study, we examine whether common and well-known substance use measures are appropriate in detecting SUD in Community Mental Health Centres (CMHCs). Material and methods: The present study used a subset of data from an evaluation of the National Plan for Mental Health. Clinicians at eight CMHCs registered socio-demographic and treatment information about their patients during a 4-week period in 2007. This included diagnostic measures, the Alcohol and Drug Use Scales and the substance use item of the Health of the Nation Outcome Scales. Prevalence rates from the different substance use measures and the observed agreement between them were calculated. The prevalence rates were compared with other estimates of substance use prevalence. Results: All the different measures gave low prevalence rates of SUD, and the inter-measure agreement was poor. A combination of the measures gave prevalence rates closer to what is expected from previous epidemiological studies. Conclusion: The CMHCs participating in this study lack sufficient diagnostic routines and specific instruments to identify SUD. Clinical research that relies on methods used in this study will need combined approaches to provide reliable findings. Both clinical practice and research would benefit from valid, reliable screening methods and diagnostic procedures.