People with heart disease who received the shingles vaccine were almost half as likely to experience a serious heart-related event within a year compared to those who did not receive the vaccine. These findings come from research presented at the American College of Cardiology’s Annual Scientific Sessions (ACC.26).
The study looked at data from more than 246,822 U.S. adults diagnosed with atherosclerotic heart disease, which is caused by plaque buildup in the arteries. The results add to evidence that the shingles vaccine may offer benefits beyond preventing shingles, including reducing the risk of diseases such as heart disease and dementia.
“This vaccine has been shown time and time again to have cardioprotective effects that reduce heart attacks, strokes, and deaths,” said Robert Nguyen, MD, a resident at the University of California, Riverside and lead author of the study. “If you look at the most at-risk populations, people who already have cardiovascular disease, these protective effects may be even greater than in the general population.”
Why the shingles vaccine can protect your heart
The Centers for Disease Control and Prevention (CDC) recommends the shingles vaccine for adults age 50 and older and younger people with weakened immune systems. This vaccine protects against shingles, which causes a painful rash and can sometimes cause long-term nerve pain. When the virus that causes chickenpox becomes active again in the body, symptoms often occur years after the initial infection.
Previous studies have shown that shingles infections can cause blood clots to form near the brain and heart, increasing the risk of heart attack, stroke, and venous thromboembolism. By preventing shingles, the vaccine may also help reduce the chance of these dangerous clotting phenomena.
Large-scale study finds significant reduction in risk
To conduct this study, the researchers used TriNetX, a large database containing medical records of millions of Americans. They studied adults aged 50 and older with atherosclerosis between 2018 and 2025. The analysis included 123,411 people who had received at least one dose of the Shingrix or Zostavax vaccines and an equal number of unvaccinated people. Both groups were similar in terms of demographics and other health conditions.
Researchers focused on heart-related outcomes that occur between one month and one year after vaccination (or the same period of time for unvaccinated people). All measures showed that vaccinated people were at lower risk. They were 46% less likely to experience a major adverse cardiac event and 66% less likely to die from any cause. Additionally, the risk of heart attack was reduced by 32%, stroke by 25%, and heart failure by 25%.
Nguyen noted that these reductions are significant and comparable to the benefits seen from quitting smoking. He added that the findings support current recommendations for vaccination for adults aged 50 and older.
“Vaccines are one of the most important medicines we have to prevent disease,” he said. “Especially in an era of disinformation, patients can be unsure whether they should receive the vaccine. These results provide another reason for patients to choose to receive the vaccine.”
Limitations and long-term effects
This analysis only tracked results during the first year after vaccination, so long-term effects may vary. However, a previous study published in 2025 found that shingles vaccination was associated with a 23% reduction in cardiovascular events in generally healthy adults, an effect that could last up to eight years.
One limitation is that people who choose to get vaccinated may also engage in healthier behaviors overall. Although the researchers controlled for several health and socio-economic factors (issues related to housing and economic status, social environment, employment status, education and literacy), it is still possible that some of the observed benefits were influenced by these differences. Still, this study’s large sample size and statistical approach provide strong evidence that herpes zoster vaccination is associated with a significant reduction in cardiac risk.
Dr. Nguyen will present his study, “Herpes Zoster Vaccination and Risk of Cardiovascular Events in Patients with Atherosclerotic Cardiovascular Disease,” in a poster in Hall E on Monday, March 30th at 12:30 PM Central Time / 17:30 PM Universal Time.
