A US study concluded that the shingles vaccine would reduce the risk of developing dementia by 20%.
The study, published in the scientific journal Nature, indicated that vaccinated people had a 20% reduced risk of developing dementia in the seven years following the injection, compared to those who did not receive the dose.
Links Between the Virus and Brain Decline
Researchers told The New York Times and AP News that these findings are the strongest evidence yet that certain viruses can affect cognitive function years later.
Shingles
Shingles is a viral infection that causes a painful rash, but did you know it’s caused by the same virus that causes chickenpox? The pathogen remains dormant in the nerve cells of patients who contracted the disease as children and can reactivate when the immune system is weakened.
Reactivation in the form of shingles
When the patient reaches a certain age or their immune system is weakened, the virus can reactivate, causing a painful rash that can last for weeks.
Painful and dangerous
Many people recover from shingles, but some patients develop chronic pain (the virus lodges in the nerves), and others can lose their vision if the eye becomes infected.
A link to chickenpox?
For years, scientists have suspected pathogens such as the chickenpox virus of having a direct link to dementia due to neuroinflammation or a weakened immune system.
Older studies prove this
Older studies have established the same link between a reduced risk of dementia and the shingles vaccine, but they have not been able to rule out other factors that may be responsible.
A 2013 Vaccination Campaign
According to the New York Times, the new study used data from the 2013 shingles vaccination campaign in Wales. Health officials set an age limit for the injection, as well as a specific date.
A “Natural Experiment for Researchers”
The threshold, set at 79 years, constituted a “natural experiment for researchers.” Vaccinated patients were only one week younger than those who did not meet the criteria.
A Multi-Year Study
Experts analyzed the medical records of more than 280,000 people aged 71 to 88 and tracked their health for years. About half of them had received the vaccine.
Eliminating Other Factors
Using this information, the experts compared the two groups. The researchers ruled out any other factors that could influence dementia, such as lifestyle or medications, which could increase the risk of Alzheimer’s disease.
This is pretty strong evidence”
“This is pretty strong evidence,” Dr. Anupam Jena of Harvard Medical School, who was not involved in the study but analyzed it for the journal Nature, told the New York Times.
