Shingrix shingles vaccine
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The newest shingles vaccine may be more effective than older versions at delaying or even preventing the onset of dementia.
Vaccination against shingles has previously been linked to protection against dementia. Now, a vaccine called Shingrix, available since 2017, appears to reduce the risk of developing dementia over the next six years by 17% compared with an older vaccine called Zostavax.
Shingles occurs when the varicella-zoster virus (which causes chickenpox and stays in the body) reactivates when the immune system weakens, such as when someone is stressed or undergoing chemotherapy. This can cause a painful rash that can sometimes become infected or leave scars.
Because the risk of shingles increases with age, doctors usually recommend that older people (age 50 in the United States and 65 in the United Kingdom) get the vaccine, followed by a booster shot about six months later.
Until seven years ago, the most common vaccine, Zostavax, was based on a live virus. Appears to be linked to lower risk of dementiaAlthough there is a link between different types of vaccines and dementia Has been controversial.
Recently, several countries have phased out Zostavax in favor of the more effective Shingrix, a recombinant vaccine that takes a small piece of DNA from a pathogen and inserts it into bacteria or yeast cells, which then produce its proteins. These proteins then trigger an immune response in the body.
Want to know how this vaccine affects dementia risk? Maxime Taquet Researchers at the University of Oxford and their colleagues collected medical records from 103,837 individuals in the United States who were vaccinated after the recombinant vaccine was introduced in November 2017, and another 103,837 individuals who were vaccinated before then.
They then selected 100,532 people in each group, with an average age of 71, who received the shingles vaccine during each time period and excluded people who received both vaccines at the same time.
The team looked at medical records after the first shingles vaccination and found that people who received the vaccine after November 2017 were 17% less likely to develop dementia in the next six years than those who received the vaccine before that. It’s possible that the reduced risk lasted beyond six years, but the declining number of participants meant the researchers didn’t study this.
Although men and women develop shingles at similar rates, women appear to benefit particularly from the new vaccine.
The reason for the reduced risk is unclear, but it is possible that shingles infection can lead to dementia, so a vaccine that is more effective at protecting against the virus would also be better at protecting against dementia, Taquet said.
The study was very thorough, even though it was based on medical records and didn’t provide other important information like people’s physical activity and diet. Pascal Gerdsetzer Researchers at Stanford University in California say a healthy lifestyle may reduce the risk of dementia while people wait for a more effective vaccine to become available.
but Richard Wright Researchers at the University of Edinburgh in the UK pointed out that a variety of vaccines are associated with a lower incidence of dementia. For example, the Bacillus Calmette-Guérin (BCG) vaccine protects against tuberculosis and is also used to treat bladder cancer. Linked to a 45% lower risk of dementia.
Therefore, Rath said, the results may be due to the vaccine giving the body an overall immune boost, rather than protection against shingles, which specifically reduces our risk of dementia.
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