Shingles Vaccine Linked to Heart and Brain Benefits, but Doctors Urge Caution

A growing body of observational research indicates that the shingles vaccine Shingrix may offer significant protective effects beyond preventing the painful skin condition, including reducing cardiovascular risks and delaying dementia. However, medical professionals emphasize that randomized controlled trials are necessary to substantiate these findings before the vaccine is recommended for such purposes.

Published last month in Nature Medicine, a study led by the University of Oxford found that adults aged 60 and older who received Shingrix experienced a 10% lower risk of ischemic heart disease and a 12% reduced risk of heart failure over seven years compared to those who received Zostavax, the older vaccine no longer available in the United States.

This follows a 2024 study by the same researchers, which suggested Shingrix could postpone dementia diagnoses by approximately six months. GSK, the manufacturer, was not involved in these specific studies, although one researcher serves as a consultant for the company.

The potential longevity benefits have garnered attention from high-profile biohackers and longevity influencers. Bryan Johnson and researcher David Sinclair have publicly endorsed the vaccine for its possible contributions to extended healthspan, fueling public interest in its off-label applications.

Despite the promising data, experts like Thomas Caprio, chief of geriatrics and palliative care at the University of Rochester Medicine, caution against overstating the evidence. “It’s encouraging from a clinical perspective, but as you talk with any scientist, you know we have to be cautious about framing the evidence,” Caprio said. “It shows that there’s a potential additional benefit.”

David Nace, chief of geriatric medicine at UPMC, stressed the distinction between observational data and definitive proof. “All we can say is some studies have suggested this, but we have no reason to believe that that is actually true,” Nace said. He noted that claims such as the vaccine preventing heart disease cannot be made without stronger evidence.

To address this gap, GSK announced in July that it plans to launch a Phase 3 clinical trial involving 16,000 adults with or at risk for heart disease. The study aims to determine if Shingrix can reduce major adverse cardiac events. Recruitment is expected to begin later this year, with results potentially leading to an updated FDA label by 2029 at the earliest.

Researchers are also investigating the biological mechanism behind these benefits. Ben Hirsh, director of preventive cardiology at the Sandra Atlas Bass Heart Hospital, suggested the vaccine may reduce inflammation associated with the varicella-zoster virus, possibly through the regulation of interleukin-6, a protein linked to inflammatory responses and heart disease.

GSK’s Sanjay Gurunathan proposed a similar theory during an earnings call, suggesting the vaccine might broadly dial down age-related inflammation, including neuroinflammation in the brain.

Nevertheless, shingles vaccination rates remain low. According to a 2023 CDC survey, only about 24% of eligible Americans have completed both doses. Physicians attribute this partly to the vaccine being deprioritized compared to shots for flu, pneumonia, and COVID-19, which pose more immediate deadly threats.

For now, doctors advise patients to focus on established heart health practices, such as exercise, smoking cessation, and blood pressure management, rather than seeking the vaccine solely for cardiovascular protection.