Overview
- The Neurology paper, covered Tuesday, analyzed health claims from about 165,000 people aged 65 and older using a design that mimics a randomized trial.
- The high-dose formulation, which contains about four times more antigen than the standard shot, was linked to nearly a 55% lower risk of Alzheimer’s over about two years.
- Women saw a stronger and longer-lasting association with lower risk, while results for men were smaller and less consistent across analyses.
- The absolute difference was modest at roughly 0.54 percentage points over 25 months, and the authors estimate about 417 women would need the higher dose to prevent one new case.
- Because the study is observational and based on claims data that can miss or mislabel diagnoses, the team cautions against causal claims and calls for longer, randomized and mechanistic studies.