Abstract
Combination therapy is commonly used to achieve better glycemic control, but Medication Regimen Complexity (MRC) can pose challenges for treatment adherence and outcomes. While some studies have explored the impact of MRC on patient outcomes, evidence remains inconclusive. Therefore, we aimed to explore the impact of MRC on diabetes management. This rapid review systematically identified studies on diabetes patients with complex medication regimens and their clinical and nonclinical outcomes. A comprehensive search was conducted across four databases (PubMed, Web of Science, Scopus, and Cochrane) from January 1967 to September 2023. Study quality was assessed using the Joanna Briggs Institute tool, while the overall evidence certainty was evaluated using the GRADE approach. Thirteen studies met the inclusion criteria, of which 11 focused on type 2 diabetes. The primary outcomes assessed were glycemic control and medication adherence. While findings on glycemic control conflicted among 12 studies, most indicated that higher MRC was associated with poor glycemic control. Four studies reported improved adherence with lower MRC. Additionally, high MRC was associated with greater medication burden and diabetes-related distress, though its impact on body weight remained inconclusive. Conversely, regimen simplification was linked to improved quality of life and increased treatment satisfaction. In conclusion, the findings suggest that MRC may contribute to various challenges in diabetes management. Simplifying regimens and standardizing outcome assessments are essential for optimizing treatment strategies in both practice and policy.