Welsh Studies Link Shingles Vaccine to 29.5-Point Drop in Dementia Deaths
Updated
Updated · ScienceBlog.com · Aug 22
Welsh Studies Link Shingles Vaccine to 29.5-Point Drop in Dementia Deaths
3 articles · Updated · ScienceBlog.com · Aug 22
Summary
A Welsh follow-up study found shingles vaccination was associated with a 29.5-percentage-point lower rate of dementia-listed deaths among 14,350 people already diagnosed with dementia, based on nine years of follow-up.
That estimate came from a birthday cutoff in Wales’ 2013 rollout: people born on or after Sept. 2, 1933 gained vaccine access, creating a sharp uptake gap—47.2% versus 0.01%—that reduced typical healthy-vaccinee bias.
The mortality signal was statistically fragile: the confidence interval ran from 0.6 to 62.9 percentage points, and the P value was 0.046, so the study suggests a possible benefit rather than proving treatment effect.
An earlier analysis of 282,541 Welsh adults without dementia linked the same vaccine rollout to a 3.5-percentage-point reduction in new dementia diagnoses over seven years, about a 20% relative decline.
Researchers say the findings justify further study, but the Welsh program used Zostavax—not the newer Shingrix now used in Britain—and the results do not establish causation or transfer directly to other vaccines.