Metformin adherence lowers dementia risk in patients with type 2 diabetes

For this purpose, the researchers identified diabetic patients with metformin-included combination anti-glycemic therapy from the National Health Insurance Research Database. The patients were then categorized into metformin-adherent and -nonadherent groups based on the medical record of the prescription's first year. Patients with severe diabetic complications, those contraindicated with metformin and having poor drug compliance were excluded. The study outcome was a diagnosis of Parkinson's disease or dementia.

The study led to the following findings:

• A total of 31,384 matched pairs were included after using propensity score matching, and both groups were followed up for an average of 5 years.
• Metformin adherence was linked with a remarkably lower dementia risk (adjusted hazard risk ratio (aHR)=0.72) but not PD (aHR=0.97).
• Subgroup analysis showed that the dementia risk was significantly reduced in metformin-adherent both male and female patients aged >65 or ≤ 65 years, and with or without concurrent insulin treatment.
• This effect was not impacted by concurrent insulin treatment, which may eliminate the bias due to the severity of diabetes mellitus.

"Despite the launch of several new oral anti-glycemic agents, metformin may provide further benefit in lowering dementia risk beyond conventional glycemic control as per the real-world evidence," the researchers concluded.

Reference:

Chen, P., Hong, C., Chen, W., Chan, L., & Chien, L. (2023). Metformin adherence reduces the risk of dementia in patients with diabetes: A population-based cohort study. Endocrine Practice. https://doi.org/10.1016/j.eprac.2023.01.007