<h4>Introduction</h4>Whether reductions in glycated hemoglobin (HbA1c) levels and body mass index (BMI) mediate the association between glucagon-like peptide-1 receptor agonists (GLP-1RAs) and Alzheimer's disease and related dementias (ADRD) risk is unknown.<h4>Methods</h4>This cohort study included 22,908 patients aged ≥ 50 years with type 2 diabetes (T2D) newly prescribed GLP-1RA or other second-line glucose-lowering drugs (GLDs). This evidence concerns the gene GLP1R and early-onset autosomal dominant Alzheimer disease.