GLP-1 RAs reduce dementia risks more than metformin

Researchers report that treatment of type 2 diabetes with glucagon- like peptide- 1 receptor agonists (GLP- 1 RAs) more effectively reduces the subsequent risk of dementia than treatment with metformin.

The findings appeared on July 22, 2025 in BMJ Open Diabetes Research & Care

“Given the severe societal, familial, and economic burden of diabetes-related dementia, these findings raise important considerations about the role of GLP-1 [receptor agonists] as first-line therapies in [type 2 diabetes] management,” the authors said.

As background to the study, the investigators noted that there have been no previous direct comparisons between GLP- 1 RAs and metformin for preventing dementia in patients with type 2 diabetes. “This study aimed to assess the comparative effectiveness of GLP- 1 RAs and metformin in reducing dementia risk,” they said.

The researchers evaluated electronic health records from a global health research network (Trinetx) dating from 2004 to 2024. They tracked the onset of dementia in subjects with type 2 diabetes who were being treated for their diabetes with either GLP-1 receptor agonists or metformin (87,229 subjects in each group with an average age of 58).

Eligible subjects had been treated for at least 6 consecutive months.

The investigators reported that among the 87,229 subjects in each cohort, treatment with GLP- 1 RAs was associated with a significantly lower risk of overall dementia (10%), Alzheimer’s disease (12%) and non- vascular dementias (25%).

They found no significant difference between the groups for onset of vascular dementia.

The comparative treatment benefits were consistent across age groups and gender, with the strongest effect appearing among older adults and females.

The authors concluded, “GLP- 1 RAs were more effective than metformin in reducing the risk of dementia—especially AD [Alzheimer’s disease] and non- vascular types—highlighting their potential as a preferred first- line treatment in T2DM [type 2 diabetes]. Further randomized trials are warranted to validate these findings.”