New Study: Shingles Vaccine May Offer Dementia Protection

A recent study found that people who received a shingles vaccine were 20 percent less likely to develop dementia and Alzheimer’s disease over the next seven years, compared to those who weren’t vaccinated.

“This may be the strongest evidence yet to support the idea that viruses affecting the nervous system can increase the risk of dementia,” says Mohamed Elkasaby, MD, a neurologist and cognitive specialist with University Hospitals Neurological Institute. “These findings are significant and encouraging for the battle against dementia.”

What Are Dementia and Alzheimer’s Disease?

As a person ages, many develop problems with their ability to think, learn, remember, and make judgements and decisions. When cognitive impairment interferes with a person’s daily activities, it’s called dementia.

People with dementia typically struggle with memory, speech and language, problem-solving and reasoning, spatial awareness, coordination and motor skills. Dementia is usually a progressive condition that can worsen over time.

The most common cause of dementia is Alzheimer’s disease, which affects about 6.9 million people in the U.S. Though the causes of Alzheimer’s disease aren’t completely understood, the disease is characterized by a buildup of certain proteins called beta-amyloid plaques and tau tangles in the brain.

What Is Shingles?

Shingles is a common viral infection that affects about 1 in 3 adults in the U.S. The infection can occur at any age in people who’ve had chickenpox. Once you’ve had chickenpox, the virus that causes it – varicella-zoster virus – lies dormant in the nervous system, usually without causing symptoms. However, in people who are older or have weakened immune systems, the virus can reactivate years or even decades later to cause shingles: a painful rash that most often appears as a band of blisters in one area of the body.

How Might the Shingles Vaccine Protect Against Dementia?

Shingrix, the newest shingles vaccine, is more than 90 percent effective in preventing shingles and related complications. The vaccine is a two-shot series, recommended for all adults age 50 and older and earlier for immune-compromised people.

“We don’t know yet how the shingles vaccine offers protection against dementia,” says Dr. Elkasaby. “However, many researchers believe it may reduce inflammation in the brain, a process we know is linked to cognitive decline. It may also prevent reactivation of the virus from causing other harmful changes in the brain that affect memory and learning.”

“The latest study is unique because the researchers were able to compare the dementia rates of a group of 79-year-olds who were eligible to receive the vaccine to a group of 80-year-olds who narrowly missed out on eligibility,” says Dr. Elkasaby.

Hope for the Future

Dr. Elkasaby says it’s an exciting time in the fight against Alzheimer’s disease and dementia. Two medications have been approved for the treatment of early-stage Alzheimer's disease. These medications, lecanemab and donanemab, work by clearing beta-amyloid plaques from the brain, rather than just treating symptoms.

In addition, other promising medications are in different phases of development. Dr. Elkasaby is confident that the new research about the shingles vaccine, dementia and Alzheimer’s will lead to even more treatment options in the future.

Related Links

The specialized brain health and memory team at University Hospitals Neurology Institute offers comprehensive treatment for Alzheimer’s disease and other dementias.