Shingles Vaccine Reduces Dementia Risk by 20%

Prime Highlights:

The research indicates that the shingles vaccine can reduce the risk of dementia by 20% in seven years.
The study hints at potential links between the suppression of herpes zoster virus and decreased neuroinflammation, which results in cognitive well-being.

Key Facts:

The study took into account information on over 280,000 older residents of Wales, examining the effects of the Zostavax vaccine.
The findings indicated a dramatic fall in the incidence rate of dementia in the vaccinated, particularly in women.

Key Background:

Dementia, or decreased mental ability, is a burgeoning international health challenge. Researchers have been seeking methods of prevention, and vaccines have been an area of specific focus of interest. Researchers at Stanford University recently published studies to examine whether the shingles vaccine could potentially reduce the risk of dementia. The study took advantage of a natural experiment in Wales that had offered the Zostavax vaccine on an age-based schedule. Based on information from over 280,000 individuals between the ages of 79 and 88 years, researchers determined that the vaccine group was 20% less likely to develop dementia seven years after vaccination compared to those who were unvaccinated.

The protective mechanism is unclear. It is hypothesized that the vaccine prevents reactivation of the varicella-zoster virus, lowering neuroinflammation—a factor in dementia development. Another is that live-attenuated vaccines like Zostavax augment the immune system by means that are protective for cognitive impairment. Greater protection in women was also reported in the study, though the underpinning of the gender gap awaits determination.

Although the result was positive, there are two things wrong with this study. It was on a very limited age group and the Zostavax vaccine first, and then later the more effective Shingrix vaccine. Since it was an observational study, causation could not be absolutely determined. Additional research would be needed to determine whether the newer shingles shots are just as helpful and to find out more about the possible role of vaccines in reducing risk for dementia. Either way, these results contribute to an increasing body of evidence that suggests a role for vaccines in brain health and mind longevity.