High-Dose Influenza Vaccination Reduces Risk of AD in Older Adults

Objective: To evaluate whether high-dose influenza vaccination is associated with reduced risk of Alzheimer dementia (AD) compared with standard-dose vaccination in older adults. Design: Large, retrospective cohort study. Methods: Using administrative and clinical data, the authors analyzed a population of Medicare beneficiaries aged ≥65 years, applying rigorous propensity score matching to minimize confounding. The primary outcome was incident AD over longitudinal follow-up. Results: High-dose influenza vaccination was associated with a statistically significant reduction in AD risk compared with standard-dose vaccination. The effect size was modest but consistent across multiple sensitivity analyses. Subgroup analyses suggested greater benefit among older age groups and individuals with higher baseline comorbidity burden. Conclusions: The authors propose that enhanced immune response from high-dose vaccination may mitigate neuroinflammatory pathways implicated in Alzheimer disea more...