Shingles vaccine linked to lower risk of serious cardiac events

People with heart disease who received a shingles vaccine had nearly half the rate of serious cardiac events a year later compared with those who did not get the vaccine, according to a study being presented at the American College of Cardiology's Annual Scientific Session (ACC.26).

The study analyzed over 246,822 U.S. adults with atherosclerotic heart disease, a condition caused by plaque buildup in arteries. Its findings add to mounting evidence that the shingles vaccine not only protects against shingles, but may also reduce the risk of other health issues such as heart problems and dementia.

This vaccine has been found over and over again to have cardioprotective effects for reducing heart attack, stroke and death. Looking at the highest risk population, those with existing cardiovascular disease, these protective effects might be even greater than among the general public."

Robert Nguyen, MD, resident physician, University of California, Riverside and study's lead author

The Centers for Disease Control and Prevention (CDC) recommends the shingles vaccine for all adults age 50 years and older and for younger adults who have weakened immune systems. The vaccine protects against herpes zoster, an illness that causes a painful rash and can sometimes lead to long-term nerve pain. It occurs when the virus that causes chickenpox becomes reactivated in the body, typically long after the initial chickenpox infection has resolved. 

Previous studies suggest that a shingles infection can cause blood clots to form around the brain and heart, raising the risk of events such as heart attacks, strokes and venous thromboembolism. By preventing the infection, the shingles vaccine is thought to also help prevent the formation of these dangerous clots.

For the current study, researchers used TriNetX, a database that includes health records of millions of Americans, to assess rates of serious cardiac events in people age 50 years or older with atherosclerotic disease between 2018-2025. The study included 123,411 people who had received at least one dose of either the Shingrix or Zostavax shingles vaccine and the same number of people who had not received any doses of shingles vaccine. Demographics and other health conditions were similar between the two groups.

When researchers examined cardiac events occurring between one month and one year after shingles vaccination (or the same time period for unvaccinated individuals), they found that vaccination was associated with a lower risk across all outcomes studied. Vaccinated individuals were 46% less likely to suffer any major adverse cardiac event and 66% less likely to die from any cause. They were also 32% less likely to suffer a heart attack, 25% less likely to suffer a stroke and 25% less likely to develop heart failure.

These levels of risk reduction are substantial, comparable to what would be expected from quitting smoking, Nguyen said, adding that the findings support recommendations for all adults over age 50 to get vaccinated.

"Vaccines are one of the most important medicines we have to prevent disease," he said. "Sometimes patients are unsure about whether they should get a vaccine or not, particularly in an age of disinformation. These results provide another reason for them to elect to get the vaccine."

The study focused only on outcomes during the first year after shingles vaccination, so researchers noted that the lifetime impacts may differ from those observed during this time period. A previous study released in 2025 found getting the shingles vaccine was associated with a 23% lower risk of cardiovascular events in a healthy general population, and the vaccine's cardioprotective effects may last for up to eight years.

Another limitation of the current study is that people who get vaccinated may tend to have healthier behaviors than those who do not get vaccinated. Although the researchers controlled for some health behaviors and socioeconomic factors (problems related to housing and economic circumstances, social environment, employment status, education and literacy), the study may overestimate the benefits that are independently attributable to preventing shingles infections. However, researchers said the study's large size and statistical methodology still support a high degree of confidence that the shingles vaccine is associated with a significant reduction in cardiovascular risk.