A vaccine to fight dementia? It turns out there may already be one – shots that prevent painful shingles also appear to protect aging brains. A new study found shingles vaccination cut older adults’ risk of developing dementia over the next seven years by 20%. The research, published Wednesday in the journal Nature, is part of growing understanding about how many factors influence brain health as we age – and what we can do about it. “It’s a very robust finding,” said lead researcher Dr. Pascal Geldsetzer of Stanford University. And “women seem to benefit more,” important as they’re at higher risk of dementia. The study tracked people in Wales who were around 80 when receiving the world’s first-generation shingles vaccine over a decade ago. Now, Americans 50 and older are urged to get a newer vaccine that’s proven more effective against shingles than its predecessor. The new findings add another reason for people to consider rolling up their sleeves, said Dr. Maria Nagel of the University of Colorado Anschutz Medical Campus, who studies viruses that infiltrate the nervous system. The virus “is a risk for dementia and now we have an intervention that can decrease the risk,” Nagel said. With Alzheimer’s and other forms of dementia on the rise in an aging population, “the implications of the study are profound,” Dr. Anupam Jena, a Harvard physician and health economist, wrote in a Nature commentary. What is shingles? Anyone who’s had ever had chickenpox – nearly everybody born before 1980 – harbors that virus for the rest of their life. It hides in nerves and can break out when the immune system weakens from illness or age, causing painful, blister-like sores typically on one side of the body that last for weeks – what’s called shingles. About 1 in 3 Americans will get shingles, according to the Centers for Disease Control and Prevention. While most recover, it sometimes causes severe complications. If it infects an eye it can cause vision loss. Up to 20% of shingles patients suffer excruciating nerve pain months or even years after the rash itself is gone. What’s the link between shingles and dementia? It’s not clear exactly how Alzheimer’s and other types of dementia form. But certain viruses that sneak inside the nervous system – especially members of the herpes family including the chickenpox virus — have long been suspected of adding to genetic and other factors that make people more vulnerable. Last summer, doctors at Boston’s Brigham and Women’s Hospital reported that an episode of shingles could raise someone’s risk of dementia by about 20%. Partly, it’s because that virus can cause inflammation, bad for organs including the brain. It also can directly infect blood vessels in the brain, causing clots and impeding blood flow, said Colorado’s Nagel, a risk both for strokes and for dementia. More intriguing, her lab also discovered shingles can spur formation of a sticky protein called amyloid that’s one of the hallmarks of Alzheimer’s. Do shingles vaccines protect against dementia? Adults who get recommended vaccines tend to have other brain-healthy habits including exercising and a good diet, which made it hard to prove an extra benefit. Stanford’s Geldsetzer took advantage of “a natural experiment” in Wales, which opened shingles vaccinations with an age limit: anyone 80 or older on Sept. 1, 2013, was ineligible but those still 79 […]