A systematic review of the efficacy of non‐pharmacological treatments for depression on glycaemic control in type 2 diabetics

AIMS AND OBJECTIVES: This paper reported a systematic review of three randomised controlled clinical trials evaluating the efficacy of non-pharmacological treatment of depression on glycaemic control in individuals with type 2 diabetes. BACKGROUND: Depression is associated with poor adherence to self-care regimen in individuals with diabetes. A significant relationship between depression and poor glycaemic control has also been suggested. Hence, the management of depression becomes an important aspect of diabetes care. DESIGN: Systematic review. METHODS: Cochrane library, Pubmed, MEDLINE, EBM review, ProQuest Medical Bundle and SCOPUS databases were searched using the following medical subject headings or key words - depression, mood disorder, depressive symptoms, diabetes mellitus, glycaemic control, glycated haemoglobin, glucose, psychological therapy, psychotherapy, non-pharmacological therapy and cognitive behaviour therapy. The publication date was limited from 1996-2007. Studies were selected if they used a randomised controlled trial design, were written in English, used non-pharmacological treatments for treating depression, included individuals with type 2 diabetes mellitus as participants and included depressive symptoms and glycaemic control (determined by haemoglobin A(1)C) as outcomes. RESULTS: Non-pharmacological treatments of depression reduce depressive symptoms in diabetic patients. However, cognitive behaviour therapy did not improve glycaemic control. The treatment effect sizes for glycaemic control in the two collaborative-care programmes were also small. CONCLUSIONS: The available evidence indicated that non-pharmacological treatment of depression had limited effect on glycaemic control in individuals with type 2 diabetes. RELEVANCE TO CLINICAL PRACTICE: The depression-focused interventions might not achieve optimal diabetes-related outcomes. The beneficial effect of psychological treatment for glycaemic control may be strengthened by employing treatments tailored to each individual's diabetes self-care needs in addition to depression management.