OBJECTIVES: To present an overview of the research literature and current discussions on polypharmacy and its association with adverse health outcomes in adults with type 2 diabetes mellitus.

METHODS: A systematic review was conducted across three literature databases (PubMed, Web of Science, and ScienceDirect) through October 2023. Studies regarding the relationship between polypharmacy and hospitalization, death, hypoglycemia, poor glycemic control, complications as well as multi-morbidity were included in the current research. A fixed effects model was applied in the calculation of the pooled odds ratios (ORs) and 95% confidence intervals (CIs). I² statistics was deployed for the assessment of heterogeneity.

RESULTS: A total of 24 studies met the inclusion criteria, and three of them were included in the meta-analysis. The association between polypharmacy and poor glycemic control was found to be statistically significant (OR= 1.84, 95% CI [1.68-2.01], P < 0.00001, I² = 0%). The included studies also reported the association between polypharmacy and hospitalization, death, hypoglycemia, complications (diabetic foot ulcers and non-proliferative diabetic retinopathy), as well as multi-morbidity (fracture, falls, depression relapse following the discontinuation of antidepressant treatment, health-related quality of life). No significant association with stroke in adults with type 2 diabetes mellitus was reported.

CONCLUSIONS: The association between polypharmacy and hospitalization, death, hypoglycemia, poor glycemic control, several complications as well as multi-morbidity has been revealed through the current systematic literature review and meta-analysis. Such evidence reinforces the importance of greater caution and better management in drug therapies for adult type 2 diabetes mellitus patients so as to reduce related adverse health outcomes.