Shingles Vaccine May Be Linked to Lower Heart Disease Risk, New Study Suggests
Could the Shingles Vaccine Offer Benefits Beyond Preventing Shingles? The shingles vaccine is widely known for helping older adults protect themselves against a painful viral infection. But emerging research suggests
Could the Shingles Vaccine Offer Benefits Beyond Preventing Shingles?
The shingles vaccine is widely known for helping older adults protect themselves against a painful viral infection. But emerging research suggests that the newer shingles vaccine may be associated with another potential benefit: a lower risk of certain cardiovascular problems.
A recent study involving U.S. adults aged 60 and older found that people who received Shingrix, the newer shingles vaccine, experienced lower rates of several heart-related conditions over time compared with people who received the older vaccine, Zostavax.
The findings add to a growing body of research examining whether shingles vaccination might have benefits beyond preventing the infection itself.
However, there is an important distinction between identifying a promising association and proving that a vaccine directly prevents heart disease. Researchers emphasize that more evidence is needed before cardiovascular protection can be considered an established benefit of Shingrix.
What Did the Study Find?
Researchers compared two groups of older adults, each containing approximately 36,460 participants. One group had received the newer recombinant shingles vaccine, Shingrix, while the other had received the older live-virus vaccine, Zostavax.
The researchers followed cardiovascular outcomes over several years and found that the Shingrix group had lower rates of multiple heart-related conditions.
Compared with people who received Zostavax, those who received Shingrix were associated with:
- A 10% lower relative risk of ischemic heart disease, which occurs when blood flow to the heart muscle is reduced.
- A 12% lower relative risk of heart failure, a condition in which the heart cannot pump blood as effectively as the body needs.
- A 9% lower relative risk of a combined outcome involving ischemic heart disease, heart failure, and ischemic stroke.
The association appeared strongest during the first few years following vaccination and weakened over time.
These findings are encouraging because cardiovascular disease remains a major cause of illness and death, particularly among older adults. Even relatively modest changes in risk could matter at a population level.
Still, the percentages represent relative differences between the groups, not the percentage of people who would necessarily avoid a heart attack or other cardiovascular event by getting vaccinated. An individual’s absolute benefit, if any, would depend on their underlying risk and other factors.
Why Comparing Two Vaccines Matters
Earlier research had also suggested a possible connection between shingles vaccination and better cardiovascular outcomes. However, studies comparing vaccinated people with those who remained unvaccinated can be difficult to interpret.
People who choose vaccination may also be more likely to receive preventive healthcare, manage chronic conditions, exercise, or follow medical advice. These differences can influence health outcomes independently of the vaccine.
Researchers refer to this challenge as healthy-vaccinee bias.
By comparing people who received two different shingles vaccines, investigators attempted to address some of the limitations associated with comparing vaccinated and unvaccinated populations.
The two vaccines differ in how they stimulate the immune system. Shingrix uses a non-live component of the varicella-zoster virus along with an adjuvant designed to strengthen the immune response. Zostavax used a weakened live virus.
This comparison offers a useful way to investigate whether the type of vaccine may be associated with different long-term health outcomes.
However, it does not eliminate every potential source of bias. Differences between the groups, including when they were vaccinated and their health characteristics, may still influence the results.
The study was observational rather than a randomized clinical trial. That means it can identify an association, but it cannot definitively establish that Shingrix itself caused the lower cardiovascular risk.
How Might Shingles Vaccination Affect the Heart?
Scientists have several possible explanations for the observed association, although the study did not establish the biological mechanism.
Inflammation may play a role
Inflammation is part of the body’s normal immune response. But persistent, inappropriate inflammation can contribute to the development and progression of cardiovascular disease.
Shingrix contains an adjuvant called AS01B, which helps stimulate a strong immune response to the vaccine. Researchers are interested in how immune activation and changes in immune regulation might influence broader health outcomes.
However, it has not been established that AS01B directly reduces harmful cardiovascular inflammation or that this mechanism explains the findings. More research is needed before a specific anti-inflammatory effect can be credited with protecting the heart.
Preventing shingles could reduce cardiovascular stress
Another possibility is that preventing shingles may help reduce cardiovascular complications associated with the infection.
Shingles occurs when the varicella-zoster virus, which causes chickenpox, becomes active again after remaining dormant in the body. It can cause a painful rash and, in some people, persistent nerve pain and other complications.
An episode of shingles can also trigger systemic inflammation and changes in blood clotting. These effects may contribute to a temporary increase in cardiovascular risk, particularly among people who already have underlying risk factors.
If vaccination prevents shingles episodes, it may also prevent some of the physiological stress associated with the infection.
However, this possibility does not fully explain why the newer vaccine appeared to have better cardiovascular outcomes than the older one. Further studies will be needed to understand whether the difference reflects the vaccines themselves, the prevention of shingles, or other factors.
What Does This Mean for Adults Over 50?
Shingles becomes more common as people age, partly because immune function changes over time. The infection can cause severe pain, interfere with sleep and daily activities, and sometimes lead to long-lasting nerve complications.
Shingrix is recommended in the United States for adults aged 50 and older and for certain adults aged 19 and older who are or will be immunocompromised, in accordance with current vaccination guidance.
The vaccine is given in two doses. People who are unsure whether they have been vaccinated, or who received the older Zostavax vaccine, can discuss their vaccination history and eligibility with a healthcare professional.
The potential cardiovascular findings may provide another reason for researchers to investigate the broader effects of shingles vaccination. But the current evidence does not justify getting Shingrix solely to prevent heart disease.
Its established purpose is preventing shingles and related complications. Any potential cardiovascular benefit should be viewed as an area of ongoing research rather than a guaranteed outcome.
The Vaccine Is Not a Substitute for Heart-Healthy Habits
Even if future research confirms that shingles vaccination provides some cardiovascular protection, it would not replace the steps known to reduce heart disease risk.
Cardiovascular health depends on multiple factors, including blood pressure, cholesterol, blood sugar, smoking, physical activity, nutrition, sleep, and family history.
Adults can help protect their hearts by:
- Eating a balanced diet rich in vegetables, fruits, whole grains, legumes, and other nutrient-dense foods.
- Getting regular physical activity suited to their abilities and health status.
- Avoiding tobacco and seeking help to stop smoking when needed.
- Monitoring blood pressure, cholesterol, and blood sugar as recommended.
- Taking prescribed medications as directed.
- Discussing personal cardiovascular risk and appropriate preventive screenings with a healthcare professional.
People with existing heart disease or multiple risk factors should continue following their clinician’s recommendations, regardless of their shingles vaccination status.
Could the Shingles Vaccine Have Other Unexpected Benefits?
The possible connection between shingles vaccination and heart health is part of a wider scientific effort to understand how infections, immune function, and vaccination may influence health as people age.
Researchers have also investigated associations between shingles vaccination and dementia risk. Some findings have attracted attention because they suggest that vaccines may have effects extending beyond their original targets.
These results are intriguing, but each potential benefit must be evaluated separately. Evidence suggesting an association with one outcome does not automatically establish protection against another.
Scientists will need additional research, ideally including studies designed to better address confounding factors and clarify the biological mechanisms involved, before broader claims can be made.
The Bottom Line
A new study suggests that adults who received Shingrix may have had a lower risk of several cardiovascular conditions than adults who received the older shingles vaccine. The results add to growing interest in the relationship between vaccination, immune function, and long-term health.
But the findings do not prove that Shingrix prevents heart attacks, heart failure, or strokes. The observed differences may reflect several factors, and further research is needed to determine whether the vaccine itself provides cardiovascular protection.
For eligible adults, the established benefit remains clear: Shingrix helps prevent shingles and its complications. People should discuss vaccination with their healthcare professional based on current recommendations, while continuing to rely on proven strategies for protecting their cardiovascular health.
Health Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Speak with a qualified healthcare professional about vaccination, cardiovascular risk, and individual health needs.
