Shingles Vaccine Associated with Reduced Dementia Risk: New Research

04/02/2025 Health

New research suggests that getting vaccinated against shingles might have an unexpected benefit: reducing the risk of developing dementia later in life. A study published in Nature found that older adults who received the shingles vaccine were 20% less likely to be diagnosed with dementia over a seven-year period.

The Study's Approach

Researchers at Stanford University compared dementia rates between people in Wales, UK, who were eligible for the shingles vaccine and those who weren't, thanks to a specific cutoff date for vaccine eligibility. This approach helped overcome limitations of previous studies, which struggled to account for differences in health behaviors between vaccinated and unvaccinated individuals.

The study analyzed health records of 280,000 residents born between 1928 and 1942. The results showed a significant decline in dementia risk among those who received the shingles vaccine. Similar findings were observed in data from England, further supporting the link.

Pascal Geldsetzer, an assistant professor of medicine at Stanford and senior study researcher, emphasizes the potential significance of these findings. "For the first time, we now have evidence that likely shows a cause-and-effect relationship between shingles vaccination and dementia prevention," he said.

Why This Matters

While the exact mechanism behind this protective effect remains unclear, the implications are substantial. It's possible that the vaccine directly prevents herpes zoster, which some studies suggest can contribute to dementia. Alternatively, the vaccine might trigger broader immune system changes that benefit brain health.

It's important to note that the study focused on the older Zostavax vaccine, which has largely been replaced by the more effective Shingrix. A previous study indicated that Shingrix might offer even greater dementia risk reduction.

Further research, including clinical trials, is needed to confirm these findings and fully understand the connection between shingles vaccination and dementia prevention. However, given the known benefits of preventing shingles, vaccination remains a valuable health measure for eligible older adults.

Geldsetzer team is actively seeking funds to conduct a clinical trial. He hopes to test the older Zostavax vaccine, since it’s the version they have the clearest supportive data on.