Glucagon-Like Peptide-1 Receptor Agonists and Dementia Risk Reduction in Older Adults With Type 2 Diabetes: A Retrospective Cohort Study

Abstract

Objective: To evaluate the effect of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on dementia risk compared with dipeptidyl peptidase-4 inhibitors (DPP-4is) among older adults with type 2 diabetes (T2D).

Design: Retrospective cohort study using an active-comparator, new-user design with propensity score matching.

Setting and participants: Data were obtained from the TriNetX Global Collaborative Network, which includes electronic health records from 134 health care organizations worldwide. Participants were adults aged ≥65 years with T2D who initiated GLP-1RA or DPP-4i therapy between January 2017 and November 2024.

Methods: Eligible participants were matched 1:1 on baseline characteristics using propensity score matching (PSM). The primary outcome was incident dementia. Secondary outcomes included prescriptions for dementia-related drugs, Alzheimer's disease, and vascular dementia. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox proportional hazards models, and subgroup and sensitivity analyses were performed.

Results: After PSM, 82,689 patients were included in each treatment group. GLP-1RA use was associated with a lower risk of dementia compared with DPP-4i (HR, 0.58; 95% CI, 0.55-0.61; P < .0001). Stratified analyses revealed consistent risk reductions across age, sex, and GLP-1RA type. In addition, GLP-1RA was also associated with lower risks of dementia-related drug prescriptions (HR, 0.76; 95% CI, 0.70-0.81), Alzheimer's disease (HR, 0.62; 95% CI, 0.56-0.70), and vascular dementia (HR, 0.62; 95% CI, 0.55-0.70). Sensitivity analyses supported the robustness of these findings.

Conclusions and implications: GLP-1RA use in older adults with T2D is associated with a significantly lower risk of dementia compared with DPP-4i. These findings suggest the potential neuroprotective benefits of GLP-1RAs and highlight their importance in managing T2D with a view toward reducing dementia risk. Further studies are warranted to explore the underlying mechanisms and validate these observations in randomized controlled trials.

Keywords: Dementia; dipeptidyl peptidase-4 inhibitors; glucagon-like peptide-1 receptor agonists; neuroprotection; older adults; type 2 diabetes.