Overview
- A follow-up analysis in Cell reports that vaccinated people already diagnosed with dementia had a 29.5‑percentage‑point lower risk of dying from dementia over nine years, with similar reductions seen for all‑cause mortality and no mortality effect in those without dementia.
- The earlier Nature study found about a 20% lower incidence of dementia in vaccinated older adults, and the new work shows a 3.1‑percentage‑point reduction in mild cognitive impairment diagnoses over nine years among those who received the shot.
- Researchers exploited Wales’ 2013 shingles program, which made those aged 79 eligible and those just 80 ineligible, enabling quasi‑random comparisons using linked SAIL health records from 282,557 adults without prior impairment and 14,350 with dementia.
- Protective associations were stronger in women, both for reduced cognitive impairment incidence and for lower dementia‑related mortality after diagnosis.
- Investigators caution the findings are observational with unknown biological mechanisms, the analyses involved an older live‑virus vaccine rather than Shingrix, replication checks are underway, and teams are seeking funding to test causality in randomized trials.