A study by researchers at the University of Oxford has uncovered a potential link between the Shingrix shingles vaccine and a reduced risk of dementia. Published in Nature Medicine, the study analyzed health records of more than 200,000 individuals in the United States who were vaccinated against shingles. Approximately half of the participants received the newer Shingrix vaccine, while the others were vaccinated with the older Zostavax vaccine.
The results showed that those vaccinated with Shingrix had a 17% lower risk of developing dementia within the following six years compared to those who received Zostavax. This equates to an average delay of 164 days, or nearly six months, in the onset of dementia symptoms. Notably, the reduction in risk was more significant in women, at 22%, compared to 13% in men.
The study also compared dementia rates in individuals who received other vaccines, such as those for flu, tetanus, diphtheria, and pertussis. It was found that the risk of dementia was 23% to 27% lower in those who received Shingrix compared to these other vaccines. The researchers emphasize that these findings, while promising, do not establish a causal relationship between the Shingrix vaccine and reduced dementia risk. More clinical trials are needed to confirm the protective effect and to understand the underlying mechanisms.
One hypothesis is that the vaccine's adjuvants, which enhance the immune response, may play a role. Alternatively, preventing the reactivation of the herpes zoster virus, which causes shingles and is linked to neurological inflammation, might reduce the risk of dementia. The study also raises questions about the potential benefits of administering the vaccine to younger populations, such as those in their 50s, given that Alzheimer's disease and other dementias can develop decades before symptoms appear.
The findings suggest that if validated, the Shingrix vaccine could become a significant public health tool, offering a relatively simple and cost-effective method to delay the onset of dementia, a condition affecting over 55 million people worldwide.
Sample, I. (2024, July 25). Study raises hopes that shingles vaccine may delay onset of dementia. The Guardian. Retrieved from https://amp.theguardian.com/society/article/2024/jul/25/shingles-vaccine-shingrix-may-delay-dementia-onset-study
