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Two new studies suggest that getting a vaccine to prevent the pain of shingles may also have a benefit to your memory.
An estimated 98% of U.S. adults Have had chickenpox You are at risk of getting shingles, both of which are caused by the varicella zoster virus, which belongs to the herpes family.
The herpes virus is insidious and can lie dormant in the roots of nerves. During times of stress, illness, or when the immune system is weakened, the virus can reactivate. This reactivation of the virus can occur in the following ways: Herpes zosterShingles is a linear rash that spreads around the torso, neck, and face. The pain of shingles varies from person to person but can range from a tingling to a burning pain that can last for several weeks.
more and more, The researchers believe Some herpes viruses can lie dormant in the brain and become reactivated if the immune system is not on guard, which could theoretically cause brain damage. Facilitate Onset of dementia.
There is no cure for shingles, but it can be treated with antiviral drugs and there is also a vaccine. The first shingles vaccine, Zostavax, was approved in the United States in 2006. In 2017, a more powerful vaccine, Shingrixis now available. The U.S. Centers for Disease Control and Prevention currently Shingrix Recommends Zostavax is appropriate for adults over 50 years of age.
While Zostavax contained a live, weakened virus, Shingrix contains only part of the virus — a protein on the virus’s outer surface. Both vaccines work by teaching the body to recognize and fight off the real virus when it starts to cause problems.
In clinical trials, Shingrix was 97% effective in preventing shingles. Zostavax effectivenessIt depends on your age. Shingrix may also offer longer-term protection, but this is still being studied.
Two new studies are tapping into this history, looking back at the medical records of hundreds of thousands of people who got the Shingrix vaccine and comparing how often they were diagnosed with dementia with people who got other types of vaccines.
While it’s difficult to eliminate all biases from observational studies like this, the researchers specifically sought to avoid the healthy user effect, the idea that certain people who are more likely to care for their health are also more likely to engage in various behaviors, such as going to the doctor regularly, exercising, getting vaccinated, etc. Similarly, people who aren’t vaccinated could be people who are too frail or sick to be vaccinated, or who lack access to regular medical care.
It is behavioral patterns and personal circumstances, rather than anything specific, that determine an individual’s risk of various diseases, and when researchers try to compare vaccinated and unvaccinated people, they risk comparing two fundamentally different groups and incorrectly attributing the differences solely to vaccination.
The first study Released Thursday The study, published in the journal Nature Medicine, looked at dementia diagnoses in more than 100,000 people aged 65 and older who received the Zostavax vaccine, and about 100,000 adults aged 65 and older who received the Shingrix vaccine.
One of the study’s authors, an immunologist, is a paid consultant to GlaxoSmithKline (GSK), the maker of the Shingrix vaccine, but the researchers said the company had no involvement in the research.
“In fact, they didn’t even know we’d done it until the paper was accepted for publication, because we wanted to do everything we could to avoid any potential conflicts of interest,” study author Dr. Paul Harrison, a psychiatrist at the University of Oxford in the UK, said at a press conference.
Researchers found that people who received the Shingrix vaccine were 17% less likely to be diagnosed with dementia six years after the shot than those who received the less effective Zostavax vaccine.
Vaccinated people didn’t avoid dementia entirely, but it did appear to be associated with delayed diagnosis: On average, those who ultimately developed dementia went about 164 more days without a diagnosis, or about five months longer, the researchers said.
This type of study can’t prove that the vaccine is directly responsible for the differences between groups. If further studies prove that the shingles vaccine protects memory and thinking, “it could be a public health issue,” he said. That would not be a trivial discovery,” Harrison said.
Experts not involved in the study said the research adds to a growing body of evidence suggesting the shingles vaccine may help protect the brain.
“There was already evidence that older live vaccines could reduce the risk of Alzheimer’s disease,” Dr Andrew Doig, a biochemist at the University of Manchester, said in written comments.
It looks like the new vaccines may reduce the risk even further, he says.
“This is an important result and parallels the effectiveness of recent antibody drugs for Alzheimer’s disease. “I’m sick,” Doig said.
The association was stronger in women who got Shingrix, but it’s not clear why. Compared with women who got Zostavax, women had a 22% lower risk of developing dementia within the next six years. Men had about a 13% lower risk.
The team then compared older adults who received the Shingrix vaccine with those who received the influenza vaccine and the combined diphtheria-pertussis-tetanus vaccine. The risk of dementia in older adults who received Shingrix was 23% lower than in those who received the influenza vaccine, and 28% lower in those who received the tDAP vaccine, further supporting the idea that there is something special about getting the shingles vaccine that lowers dementia risk.
“It will be important to study this apparent effect further,” Dr Shana Scales, research director at Alzheimer’s Research UK, said in written comments.
“While research into whether vaccines affect dementia risk is ongoing, people should be aware that there are other factors that are clearly associated with an increased risk of dementia, including smoking, high blood pressure and excessive alcohol consumption,” Scales added, and controlling for these could make a difference to brain health.
The second study, due to be presented at the Alzheimer’s Society International Conference on Tuesday, took a similar approach to the Oxford study and its conclusions mirror those of the Oxford study.
The study was sponsored by GSK, which issued a news release explaining the results. The full study has not yet been peer-reviewed or published in a medical journal.
The study also made use of another large electronic health records database owned by healthcare company Optum.
By mining data on nearly 600,000 patients, the researchers were able to compare dementia diagnoses in people over 50 who had received the shingles vaccine (the old Zostavax vaccine or the new Shingrix vaccine) with those who had received the Pneumovax vaccine, which prevents bacterial infections that cause strep throat and pneumonia.
People in the study were less likely to be diagnosed with dementia after receiving the shingles vaccine than people who only received the Pneumovax vaccine.
After five years, people who received Zostavax were 8% less likely to be diagnosed with dementia than people who received only Pneumovax vaccine, and people who received Shingrix were about 20% less likely to have a dementia diagnosis noted in their health records than people who received only Pneumovax vaccine. These results suggest that protection against the varicella zoster virus was responsible for the differences, rather than an effect of vaccination alone or of healthy users.
The study also found that the newer shingles vaccine offered a greater benefit than the older one: People who got the Shingrix vaccine were about 23% less likely to be diagnosed with dementia five years later compared with those who got the Zostavax vaccine.
While the findings are intriguing, the association says more research is needed before researchers can be sure the shingles vaccine will have that effect.
“The data at present suggest that further research is needed, rather than a signal that we should change the way the vaccine is used,” said Dr Phil Dormitzer, head of vaccines research and development at GSK.
So for now, the biggest reason to get the shingles vaccine is to avoid the suffering of shingles.
