The evidence for potential GLP-1 RA efficacy in AD comes from pharmacoepidemiological studies that have demonstrated an association of their use in T2D and reduced incidence of dementia.9 10 A nested case-control study based on dementia diagnosis within a cohort of 176 people with T2D showed that GLP-1 RAs were associated with a significantly reduced odds of dementia after adjusting for demographic confounders, acute and chronic diabetes complications and use of other types of antidiabetic agents (OR 0.58, 95% CI 0.42 to 0.81, relative to placebo).10 This evidence concerns the gene GCG and type 2 diabetes mellitus.