Shingles Vaccine Cuts Major Cardiac Events by 46 Percent in Heart Disease Patients, Rivaling the Benefits of Quitting Smoking
A study of nearly 250,000 U.S. adults finds the shingles vaccine dramatically reduces heart attacks, strokes, and deaths in people with existing cardiovascular disease.
Overview
A large retrospective study presented at the American College of Cardiology’s Annual Scientific Session (ACC.26) in New Orleans has found that the shingles vaccine is associated with dramatically lower rates of heart attacks, strokes, and deaths among people who already have cardiovascular disease. The findings, reported by ScienceDaily, show that vaccinated patients experienced a 46 percent reduction in major adverse cardiac events within one year, a level of protection that researchers say rivals the benefits of quitting smoking.
What We Know
The study, led by Dr. Robert Nguyen, a resident physician at the University of California, Riverside, analyzed medical records from 246,822 U.S. adults diagnosed with atherosclerotic cardiovascular disease, a condition caused by plaque buildup in the arteries. Using the TriNetX database, researchers matched 123,411 patients who had received at least one dose of the Shingrix or Zostavax shingles vaccine against an equal number of unvaccinated individuals with similar demographics and health conditions, according to EurekAlert.
The results were striking across every measured outcome. Within one year of vaccination, patients showed a 46 percent lower risk of major adverse cardiac events, a 66 percent lower risk of death from any cause, a 32 percent lower risk of heart attack, a 25 percent lower risk of stroke, and a 25 percent lower risk of developing heart failure, as reported by ScienceDaily.
“This vaccine has been found over and over again to have cardioprotective effects for reducing heart attack, stroke and death,” Dr. Nguyen said, according to EurekAlert. He noted that the protective effects in patients with existing heart disease “might be even greater than among the general public.”
The proposed mechanism centers on the herpes zoster virus itself. Previous research has shown that a shingles infection can trigger the formation of blood clots near the brain and heart, raising the risk of heart attacks, strokes, and venous thromboembolism. By preventing the underlying infection, the vaccine appears to also prevent these dangerous clotting complications, according to ScienceDaily.
The new findings build on earlier work. A separate study of 1.27 million South Koreans published in the European Heart Journal in May 2025 found that shingles vaccination lowered cardiovascular risk by 23 percent, with protection persisting for up to eight years, as reported by ScienceDaily. That study found the greatest benefit in men, people under 60, and those with unhealthy lifestyles including smoking, drinking, and physical inactivity.
What We Don’t Know
The ACC.26 study examined only outcomes within the first year after vaccination. Whether the 46 percent reduction in cardiac events holds over longer periods in this specific high-risk population remains to be determined, though the South Korean data suggesting eight-year durability provides some grounds for optimism.
The study’s retrospective design introduces inherent limitations. People who choose to get vaccinated may also be more likely to engage in other healthy behaviors, exercise regularly, and maintain closer contact with healthcare providers. The researchers acknowledged this healthy-user bias as a potential confounding factor, according to EurekAlert.
It also remains unclear whether Shingrix and Zostavax confer equal cardiac protection. The study grouped recipients of both vaccines together. Since Zostavax, a live vaccine, has been largely replaced by Shingrix, a recombinant vaccine, in many countries, understanding whether the newer formulation provides the same or greater cardiovascular benefit will be important for clinical guidance.
The findings have not yet been published in a peer-reviewed journal. Results presented at medical meetings are considered preliminary until they undergo full peer review.
Analysis
The sheer size of the effect is what makes this study noteworthy. A 46 percent reduction in major cardiac events and a 66 percent reduction in all-cause mortality are figures that would be remarkable for any dedicated cardiovascular drug, let alone a vaccine designed to prevent a skin infection. That the benefit appears comparable to smoking cessation, one of the most impactful behavioral changes a patient can make, underscores its potential clinical significance.
For the roughly 18 million Americans living with atherosclerotic cardiovascular disease, the shingles vaccine could represent a simple, widely available intervention that stacks on top of existing treatments. Unlike novel therapeutics, both Shingrix and its predecessor have well-established safety profiles after years of widespread use. The practical barrier is primarily awareness: cardiologists do not typically discuss shingles vaccination with their patients, and the vaccine is generally marketed to older adults as a way to avoid a painful rash rather than as a cardiovascular tool.
If the findings survive peer review and are replicated in prospective trials, they could reshape how physicians think about vaccine benefits beyond their primary target diseases.