Abstract:
Background: Age is the strongest non-modifiable risk factor for dementia, with incidence increasing sharply after 60 years of age. However, most pharmaco-epidemiologic studies evaluate broad adult populations, potentially obscuring treatment-specific effects in older adults. Concurrently, interest has grown in repurposing antidiabetic agents for dementia prevention. Sodium-glucose cotransporter-2 (SGLT-2) inhibitors and dipeptidyl peptidase-4 (DPP-4) inhibitors are widely used second-line therapies for type 2 diabetes, yet current guidelines do not provide class-specific recommendations regarding their comparative impact on dementia risk.
Objective: This meta-analysis is the first to directly compare SGLT-2 inhibitors versus DPP-4 inhibitors in reducing dementia risk, with analyses restricted to adults aged ≥60 years to better characterize effects in this high-risk population.
Methods: A systematic literature search of PubMed, Scopus, and Web of Science was conducted on September 19, 2025, to identify comparative studies evaluating dementia outcomes among older adults treated with SGLT-2 or DPP-4 inhibitors. Risk ratios (RRs) with 95% confidence intervals (CIs) were pooled using a random-effects model. Certainty of evidence was assessed using the GRADE approach.
Results: Seven studies published between 2023 and 2025 were included, encompassing 743,641 participants. Pooled analysis demonstrated a significantly lower risk of incident all-cause dementia among SGLT-2 inhibitor users compared with DPP-4 inhibitor users (RR 0.72; 95% CI 0.59–0.86; p = 0.0005), with moderate certainty of evidence. Subgroup analyses of three studies further revealed that SGLT-2 inhibitors were associated with a significantly reduced risk of Alzheimer’s disease (RR 0.60; 95% CI 0.56–0.65; p < 0.00001) and vascular dementia (RR 0.54; 95% CI 0.48–0.60; p < 0.00001).
Conclusion: Among adults aged ≥60 years, SGLT-2 inhibitor therapy is associated with a significantly lower risk of all-cause dementia, Alzheimer’s disease, and vascular dementia compared with DPP-4 inhibitors, suggesting potential neuroprotective benefits in older populations with diabetes.
Keywords: SGLT-2 inhibitors; DPP-4 inhibitors; dementia; Alzheimer’s disease; vascular dementia


