“We found that getting the flu shot in older adults reduced the risk of developing Alzheimer’s disease for several years. The strength of this protective effect increased with the number of annual flu shots – in other words, Alzheimer’s disease developed least frequently among those who consistently got flu shots every year,” said Dr. Avram S. Bukhbinder from the University of Texas at Houston. During the four-year follow-up, 5.1 percent of influenza-vaccinated people developed Alzheimer’s disease and 8.5 percent of unvaccinated people.
Two years earlier, researchers at the university had found a possible connection between the flu vaccination and a reduced risk of Alzheimer’s. But that sample was now much larger: it included 935,887 vaccinated against influenza and 935,887 unvaccinated.
Researchers can only speculate as to why the flu vaccine protects against Alzheimer’s. It is probably not a specific effect of the flu vaccine, because there are indications that several other vaccinations can also protect against Alzheimer’s.
Which: DOI 10.3233/JAD-220361