[Sportschosun, Jang Jong-ho] A study has found that shingles vaccination is associated with a 24% lower risk of developing dementia. However, the researchers said the exact reason for this effect remains unclear.
A joint research team from Brown University and the University of Delaware recently published a paper in the international journal Annals of Internal Medicine. Based on health data from 509,926 people, with an average age of 79 and two-thirds of them women, the study found that those who received the recombinant herpes zoster vaccine (RZV) had a significantly lower risk of dementia than those who did not.
The researchers followed the participants for an average of four years. During that period, the dementia rate was 19% in the vaccinated group, compared with 24% in the unvaccinated group. That means the vaccinated group had about a 24% lower risk of dementia.
The team explained, "We still do not know exactly why the shingles vaccine lowers the risk of dementia, but we are examining several possibilities."
Experts believe that shingles itself may raise the risk of dementia. Shingles is a disease caused by the reactivation of the varicella-zoster virus (VZV), and it can trigger severe pain, rashes, and nerve damage.
In particular, shingles is known to promote neuroinflammation that affects the brain and spinal cord. Neuroinflammation is considered one of the major factors that increase the risk of stroke and dementia.
The researchers suggest that the vaccine may reduce dementia risk by activating the immune system and suppressing these inflammatory pathways.
However, some experts stressed that a more cautious approach is needed.
"It is an interesting result, but the study is still at an early stage," they said. "It is not enough evidence to change current medical practice."
The researchers also added, "These findings were obtained through an observational study. Therefore, we cannot conclude that the shingles vaccine directly caused the reduction in dementia risk." They said that causality should be confirmed through future randomized controlled trials.
Jang Jong-ho, bellho@sportschosun.com
