As we age, our health concerns often shift towards maintaining mental acuity and preventing conditions such as dementia. In a remarkable turn of scientific discovery, it appears that a common vaccine, typically administered to prevent a painful skin condition, may also offer a protective shield against the onset of dementia.
Shingles, a condition that can cause severe pain and discomfort, is the result of the reactivation of the varicella zoster virus, the same virus responsible for chickenpox. For those who have suffered through chickenpox, the virus lies dormant in the body, only to potentially re-emerge later in life as shingles. This is particularly concerning for older adults, as the risk of shingles increases with age.
However, a new study published in the prestigious journal Nature has shed light on an unexpected benefit of the shingles vaccine. Researchers in Wales analysed data from over 280,000 older adults and discovered that individuals who received the original live virus shingles vaccine were 20% less likely to develop dementia of any type compared to those who were not vaccinated.
This finding is not only surprising but also aligns with previous research that hinted at a connection between the Shingrix shingles vaccine, which replaced the live virus version in 2020, and a reduced risk of dementia, particularly in women. The Shingrix vaccine, which targets a small segment of viral DNA, has been shown to have a more enduring effect than its predecessor.
The study’s robust design was made possible by a unique public health policy in Wales, which created a ‘natural experiment’ to assess the vaccine’s impact on dementia risk. The vaccine’s rollout on September 1, 2013, was offered to individuals who were 79 years old on that date but not to those who had turned 80. This allowed researchers to compare two groups of similar health characteristics, differing only by one week in age, essentially creating a control group and a treated group.
Dr Pascal Geldsetzer, an assistant professor of medicine at Stanford University and a senior author of the study, likened the research to a randomised controlled trial, the gold standard in scientific research. The study’s findings are particularly compelling, as they suggest a strong protective effect of the vaccine against dementia, a notion supported by other research indicating that herpes viruses may influence dementia risk.
The exact mechanism by which the chickenpox virus increases the risk of dementia remains unclear. However, it’s known that the reactivation of the virus can lead to the accumulation of abnormal proteins associated with Alzheimer’s disease. Additionally, the virus may trigger the reactivation of herpes simplex, which has been linked to dementia in earlier research.
Herpes viruses are notorious for their ability to remain in the body, lying in wait until the immune system weakens with age, allowing for the resurgence of shingles. This is why the shingles vaccine is recommended for individuals aged 50 and older in the US, administered in two doses several months apart.
Further bolstering the case for the shingles vaccine’s protective role against dementia are findings from a 2024 study published in Nature Medicine. This study, which analysed medical records from over 100,000 patients, suggested that the newer shingles vaccine was associated with even better protection against dementia.
While the research is promising, it’s important to note that it does not equate to a randomised controlled trial. Nonetheless, the real-world implications are significant and could potentially influence the US Food and Drug Administration to consider allowing the addition of dementia prevention to the vaccine’s label.
For now, the message is clear: getting vaccinated against shingles may not only spare you from the acute pain and long-term complications of the condition but also potentially lower your risk for dementia. It’s a compelling reason to discuss vaccination with your healthcare provider, especially if you’re over 50 and have not yet received the vaccine.
As we continue to unravel the mysteries of the human body and the diseases that afflict it, it’s heartening to see that sometimes, the solutions to our most pressing health concerns may come from unexpected places. So, let’s keep an open mind and open dialogue with our doctors about the potential benefits of vaccines, not just for their immediate protective effects but also for their possible role in safeguarding our future health and well-being.
What are your thoughts on the potential link between the shingles vaccine and dementia prevention? Do you think this could change how we view the importance of vaccines for older adults? We invite you to share your thoughts and experiences in the comment section below.
Also read: Shingles vaccine access expanded
