Receipt of the shingles vaccine Zostavax may offer protective benefits against mild cognitive impairment (MCI) in cognitively healthy older adults and significantly slow disease progression in those diagnosed with dementia before vaccination, a new study showed. After 9 years of follow-up, dementia-related mortality was 30% lower among vaccinated individuals with preexisting dementia than among unvaccinated individuals, which investigators said suggests a link with slower disease progression. The study builds on earlier work that showed a link between the shingles vaccine and lower dementia risk and takes advantage of a unique opportunity to compare vaccinated and unvaccinated groups that differed only by slightly different ages. This fortifies the findings compared to previous observational studies that only found an association.
Link: Medscape Medical News (12/2025)
