Adults who received the recombinant shingles vaccine were 46% less likely to suffer a major cardiac event within a year, according to an observational study of more than 246,822 US adults with heart disease.
The findings, presented at the American College of Cardiology's ACC.26 conference in New Orleans, land alongside a separate Oxford University analysis published in Nature Medicine that tracked vaccinated patients for seven years.
Both papers point to Shingrix, the recombinant shingles shot from GSK, and both describe an association rather than proof of cause.
Researchers propose that vaccination protects the heart by preventing a shingles infection in the first place. A herpes zoster outbreak can trigger blood clots near the brain and heart, raising the risk of heart attack, stroke and dangerous clots in the veins.
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Heart attack, stroke and death rates all dropped
The ACC.26 analysis, led by Dr. Robert Nguyen, a resident physician at the University of California, Riverside, compared 123,411 vaccinated adults with atherosclerotic heart disease, a condition caused by plaque buildup in the arteries, to an equal number of unvaccinated adults.
Within a year of the shot, heart attack risk was 32% lower, stroke risk 25% lower and heart failure risk 25% lower. Deaths from any cause fell by 66%.
Oxford data show a durable seven-year benefit
The Oxford team took a different route, exploiting a natural experiment created when Shingrix was approved in the US in October 2017, displacing the older Zostavax. Roughly 36,000 recipients of each vaccine were tracked in the TriNetX health-records network over seven years.
Shingrix recipients had a 9% lower overall burden of cardiovascular disease, with a 10% reduction in ischemic heart disease and a 12% reduction in heart failure. Men saw a 12% lower stroke risk, and atrial fibrillation, an irregular heartbeat, was 7% less common.
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One theory ties the effect to Shingrix's AS01 adjuvant, an immune-boosting component absent from the older Zostavax. It may prime immune cells in a way that dampens the inflammation that drives atherosclerosis.
Who qualifies for the shot
Neither study proves the vaccine directly protects the heart, and the Oxford team notes that clinical trials will be needed before doctors can recommend Shingrix specifically for cardiovascular disease.
For now, the CDC recommends two doses of Shingrix, given two to six months apart, for all immunocompetent adults aged 50 and older. Immunocompromised adults from age 19 are also eligible.
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This article is made and published by Mie Hermansen, who may have used AI in the preparation.