Shingrix Cuts Dementia Risk 24% in 500,000 Nursing Home Residents Over 4 Years

2 articles · Updated · The Boston Globe · Jun 18

More than 500,000 U.S. adults aged 66 and older entering nursing homes were studied, and those given at least one Shingrix dose were 24% less likely to develop dementia over four years.
Dementia developed in 18.8% of vaccinated residents versus 24.6% of unvaccinated peers — about one in 17 cases potentially prevented, according to lead author Kaleen Hayes of Brown University.
The Annals of Internal Medicine study used Medicare claims and health records from 2017 to 2022 and a trial-mimicking design to examine a population often excluded from vaccine and drug research.
Researchers said the mechanism remains unclear: protection may come from preventing shingles itself, or from vaccine-related effects on inflammation, blood vessels or neuroimmune function.
The findings add to earlier large studies linking shingles vaccination to lower dementia risk, but outside experts said the evidence is still observational and not yet a basis to give Shingrix specifically to prevent dementia.