Associations of semaglutide with first-time diagnosis of Alzheimer's disease in patients with type 2 diabetes: Target trial emulation using nationwide real-world data in the US.
Level 3 - non-randomized controlled study
Non-randomized target trial emulation (controlled cohort study) using electronic health records.
PubMed 39445596 · doi:10.1002/alz.14313
What was done
A target trial emulation was conducted using a nationwide electronic health record database of 116 million US patients. Seven target trials were emulated among 1,094,761 eligible patients with type 2 diabetes mellitus and no prior Alzheimer's disease (AD) diagnosis. Semaglutide was compared with seven other antidiabetic medications for first-ever AD diagnosis over a 3-year follow-up period using Cox proportional hazards and Kaplan-Meier survival analyses.
What was found
Semaglutide was associated with a significantly reduced risk for first-time AD diagnosis compared to other antidiabetic medications (40% to 70% reduction across comparisons). The association was strongest compared to insulin (hazard ratio [HR] 0.33, 95% CI: 0.21 to 0.51) and weakest compared to other GLP-1 receptor agonists (HR 0.59, 95% CI: 0.37 to 0.95). Semaglutide was also associated with significantly lower AD-related medication prescriptions, with consistent reductions across obesity status, gender, and age groups.
Why it matters
This real-world study provides large-scale observational evidence that semaglutide is associated with lower incidence of Alzheimer's disease diagnosis in type 2 diabetes compared to other diabetes drugs, supporting further investigation in randomized controlled trials.
Limits
The study relies on electronic health record diagnostic codes, which may suffer from underdiagnosis, misclassification, or coding delays. The follow-up period of 3 years is short relative to the multi-decade trajectory of Alzheimer's pathology, and unmeasured confounding inherent to observational designs cannot be ruled out.
Cited by
- supports Studies show a reduced risk of developing Alzheimer's disease over 3 years in people using semaglutide compared to other antidiabetic agents, with the largest contrast against insulin in type 2 diabetics.