Can Shingles Vaccine Prevent Dementia? New Study Suggests a Link

New Study Reveals Shingles Vaccine Could Reduce Dementia Risk – What Does This Mean for Older Adults?

A recent groundbreaking study has highlighted an unexpected benefit of the shingles vaccine, Zostavax, revealing that it may play a significant role in reducing the risk of developing dementia. This intriguing research offers new insights into how viral infections affecting the nervous system could contribute to neurodegeneration. It not only provides a fresh perspective on dementia prevention but also supports the idea that vaccines traditionally intended for one disease may have broader health benefits.

A Unique Study Approach

The study, which was published on April 2 in Nature, is built on the analysis of over 280,000 older adults in Wales, and it showcases how the live-attenuated shingles vaccine can potentially delay or prevent dementia. Previous research had hinted at a potential connection between the shingles vaccine and reduced dementia risk, but this new study has taken the methodology a step further.

The research is noteworthy because it adopts an approach that minimizes biases found in prior studies. For instance, previous research struggled to account for the differences in health behaviors between people who got vaccinated and those who didn’t. However, the Welsh study cleverly utilized a policy that determined eligibility for the shingles vaccine based on a person's exact birth date. Those born before September 2, 1933, were ineligible for the vaccine, while those born on or after that date were eligible. This allowed the researchers to compare two groups: those who were just a week too old to get vaccinated versus those who were just a week younger and eligible for the vaccine. This design mirrors a randomized controlled trial, ensuring the groups were nearly identical except for their vaccine eligibility, offering a more solid foundation for the findings.

Key Findings: A Protective Link to Dementia

The analysis of health records revealed that receiving the shingles vaccine was linked to a 20% reduction in the probability of developing dementia over a 7-year period. Specifically, individuals who received the vaccine had a 3.5 percentage point lower chance of being diagnosed with dementia. This result was particularly pronounced in women, suggesting that factors such as stronger immune responses or higher shingles prevalence in women could contribute to this effect.

“This finding is compelling,” said Dr. Pascal Geldsetzer, the study's lead investigator and a professor at Stanford University. “We’re essentially seeing a strong protective signal for dementia across multiple datasets, not just in Wales, but also in other countries with similar vaccine rollouts, including England, Canada, Australia, and New Zealand.”

Moreover, the study emphasizes the importance of the vaccine in preventing shingles, a condition caused by the varicella-zoster virus that can have severe neurological effects. This reinforces the idea that immunizing against one viral infection might not only help avoid its direct effects but could also help protect against long-term complications, such as dementia.

What’s Next: Could Other Vaccines Offer Similar Benefits?

Dr. Geldsetzer and his team are now aiming to conduct a large-scale randomized controlled trial to further explore the neuroprotective effects of the live-attenuated shingles vaccine. Although the vaccine is no longer manufactured by pharmaceutical companies, Geldsetzer is seeking philanthropic funding to conduct this trial, which he believes could confirm the compelling evidence already gathered.

One key unanswered question is whether the newer version of the shingles vaccine, Shingrix, might have similar or even greater protective effects against dementia. Given the availability of new vaccines, it will be interesting to see whether they can deliver the same, or perhaps even better, outcomes for dementia prevention.

The Broader Implications for Public Health

The results of this study could have profound implications for public health policy, especially for older adults. Dr. Anupam Jena, an expert from Harvard Medical School, stressed the significance of the findings in a Nature commentary, noting that the shingles vaccine could become a cost-effective intervention for dementia prevention. He suggests that given the significant social and economic burden of dementia, policymakers might want to reconsider the broader value of widespread herpes zoster vaccination in older populations.

Adding to the momentum, Courtney M. Kloske, PhD, of the Alzheimer’s Association, emphasized that the study aligns with previous research that has shown a connection between flu and pneumonia vaccinations and a lower risk of Alzheimer’s disease. “While more studies are needed, this new research opens the door to a potential new strategy for dementia prevention,” she explained.

This study not only reinforces the importance of vaccination in preventing shingles, but it also highlights the potential for vaccines to serve as a critical tool in mitigating age-related diseases like dementia. For medical professionals and public health authorities, the message is clear: promoting vaccinations may have far-reaching benefits beyond just preventing specific diseases. It could be key to reducing the long-term risk of developing dementia and, ultimately, enhancing the quality of life for aging populations.

Conclusion: The Importance of Vaccination in Dementia Prevention

This study emphasizes the broader, often overlooked benefits of vaccines, urging medical professionals to reconsider the role vaccines could play in delaying or preventing dementia. It also underscores the importance of taking care of overall health, including getting vaccinated, as a potential strategy to protect against future cognitive decline. The findings challenge conventional thinking and present an exciting new area of research for future studies on aging and neurodegenerative diseases.

Learn more: https://www.nature.com/articles/s41586-025-08800-x