This recalls the controversial assertion that measles (and other) vaccinations in 3rd world countries protect against a broad range of diseases. The counter was that the families willing to get vaccinated were better off and generally healthier to begin with:
Though I am a highly vaccinated senior and really want to believe that my flu vaccine wards off dementia, I wonder if those of us getting regular flu vaccinations (about 70%) have a healthier lifestyle going in?
With so many unknowns about dementia, hard to reconcile all the data. Your thoughts, oh wise Dr. Hunter?