Severe mental illness and type 2 diabetes: using theory and research evidence to develop complex behaviour change interventions

This paper provides a critical review of the literature on severe mental illness (SMI) and type 2 diabetes and presents an argument for the development of theory‐based interventions tailored specifically for people with these co‐existing conditions. Individuals with SMI are at an increased risk of physical health problems, with a high prevalence of type 2 diabetes among this population. Yet, it is estimated that up to 70% of cases of diabetes among people with SMI are undiagnosed (Holt & Mitchell 2015), which has many clinical implications for the individuals themselves and the health care professionals involved in their care. Changes in lifestyle can significantly reduce the risk of developing diabetes in the first place and also reduce the risks of complications from the condition. However, lifestyle changes relating to diet, exercise and smoking can be particularly challenging for people with SMI. There is good evidence that educating people with diabetes about the disease in general and behaviour change to manage the condition can have a positive impact on clinical outcomes in the general population (Steinsbekk et al. 2012). However, less is known regarding the effectiveness and appropriateness of existing diabetes self‐management programmes for people with SMI. This essay will present an argument for the use of theory and research evidence to strengthen the development and implementation of new interventions specifically for people with SMI and type 2 diabetes.