SAIL Databank News. Published 28/04/2025
Researchers have discovered compelling causal evidence for the impact of the shingles vaccine on reducing the occurrence of dementia, using data from the world-renowned SAIL Databank, funded by Health and Care Research Wales.
Published in Nature, the research by Pascal Geldsetzer’s research group, with joint first authors Markus Eyting and Min Xie, tracked over 280,000 adults in Wales using anonymised health records within SAIL. The findings revealed that individuals who received Zostavax, a now-discontinued shingles vaccine, were around 20% less likely to be diagnosed with dementia over a seven-year follow-up period.
This research was made possible by a unique feature of Welsh public health policy. When the Zostavax vaccine was introduced in 2013, eligibility was based strictly on date of birth. People born on or after 2 September 1933 were offered the vaccine, while those just a day older were not – creating two ideal groups for comparison because individuals who vary in their age by only a minute degree would be expected to have similar health-related characteristics and behaviours.
Researchers observed a striking difference between these groups. Not only did the vaccinated group show a significantly lower incidence of dementia, but the protective effect was also found to be more pronounced in women.
With more than 45,000 people currently living with dementia in Wales, and projections estimating that number will more than double by 2055, these findings could open up promising new avenues for prevention.
Reflecting on SAIL Databank’s role in enabling this kind of research, Professor David Ford, Co-director of SAIL, commented:
“SAIL Databank has evolved into a world-class, internationally acclaimed research resource that is an integral part of Wales’ national informatics infrastructure and a recognised innovation leader across the UK. Its trusted, robust and agile Trusted Research Environment supports high-impact research across health, administrative and social data, and continues to support vital work like this.”
Pascal Geldsetzer, senior author and research group lead for this work, commented:
“If this is truly a causal effect, then the implications for population health, dementia care, and research into dementia would be immense. As a next step, we are now trying to raise funds from private foundations and philanthropy to more conclusively test the effect of a version of the old, live-attenuated, shingles vaccine on cognition and dementia in a randomized trial. This research would have been impossible without the rich and highly detailed data of the SAIL Databank. Our work clearly shows that important discoveries can be made if routinely collected data is made available to researchers.”
The study not only highlights the potential of vaccines in preventing chronic neurological conditions but also underscores the critical role of trusted, secure health data in enabling world-class research.
What’s next for this research?
Building on these promising findings, Pascal Geldsetzer and his research team are now seeking to take the next critical step: a randomised clinical trial to more conclusively test the cognitive benefits of the shingles vaccine. To make this possible, they are actively working to raise funds from private foundations and philanthropic sources. Their goal is to validate the observed effects in a controlled setting and explore the broader implications for dementia prevention. The team emphasises that continued support from such funding avenues is essential to translate these early insights into actionable public health strategies.