United Kingdom: Researchers have found that the approved shingles vaccine, Shingrix, may significantly reduce the risk of developing dementia. The discovery, based on a study of US medical records, highlights a potential new benefit of the vaccine beyond its primary purpose of preventing shingles, a painful condition caused by the herpes zoster virus.
The study, conducted by researchers at the University of Oxford, analysed the health records of over 200,000 US citizens vaccinated for shingles. It found that those who received Shingrix, the newer and more effective vaccine introduced in October 2017, had a 17 percent lower risk of developing dementia over six years compared to those who received the earlier Zostavax vaccine. For those who developed dementia, Shingrix recipients experienced an additional 164 days, or nearly six months, without the condition. The benefit was more pronounced in women (22percent) compared to men (13percent).
Further analysis revealed that Shingrix users had a 23 -27 percent lower risk of dementia compared to individuals vaccinated against flu, tetanus, diphtheria, or pertussis. This suggests that Shingrix might offer unique advantages in dementia prevention. The benefits were greater for women.
However additional research is needed to confirm these findings and understand the underlying mechanisms. Potential explanations include the role of adjuvants in the vaccine or the impact of shingles-related viral resurgence on dementia development.
Andrew Doig, a biochemist at the University of Manchester, emphasised the importance of conducting a clinical trial comparing Shingrix with a placebo to verify its effectiveness in dementia prevention. Doig suggested that earlier vaccination, possibly in the 40s or 50s, might enhance the vaccine’s benefits given that Alzheimer’s disease can begin years before symptoms appear.
With over 55 million people globally living with dementia, and more than 900,000 in the UK alone, these findings could have significant implications for public health if further validated.