Systematic Review of Pharmacist Interventions to Improve Adherence to Oral Antidiabetic Medications in People with Type 2 Diabetes

Objective: Poor adherence is an important challenge to healthcare professionals because it jeopardizes treatment success and increases the risk of serious complications, especially in patients with chronic diseases like diabetes. The purpose of this study was to summarize the effects of pharmacist interventions aimed at enhancing adherence to oral antidiabetic medications in patients with type 2 diabetes mellitus. Methods: Five electronic databases were searched through to March 12, 2011 to identify controlled trials reporting the effects of pharmacist interventions to improve medication adherence rates in adults with type 2 diabetes. Components of the intervention were categorized as educational, behavioural, affective or provider-targeted strategies. In addition to the impact on medication adherence rates, we recorded any reported effects on health outcomes. Results: Eight studies were included in this review. Education-related strategies were the most frequent (7 of 8 studies), and 6 of 8 studies used a combination of 2 or more strategies for the adherence intervention. Change in adherence rate was assessed using a variety of measurement methods, and 6 studies reported the effect of pharmacist intervention on clinical, economic or humanistic outcomes. Compared to a control group, 5 studies reported significant improvements in adherence rate with pharmacist intervention; however, glycemic control improved significantly in only 2 studies. Conclusions: Pharmacist interventions to improve medication adherence in diabetes generally use an educational component combined with behavioural, affective or provider-targeted strategies. Although these interventions appear to improve adherence, the effect on health outcomes has not been established. (C) 2012 Canadian Diabetes Association