Shingrix Vaccine Linked To Lower Heart Attack And Stroke Risk

A study of 70,000 U.S. adults finds that vaccination with the Shingrix vaccine is linked to a 12% lower cardiovascular disease risk, potentially preventing heart attacks, strokes, and heart failure.

Study finds lower cardiovascular risk after Shingrix

Researchers tracking adults aged 60 and older find those who received the two-dose Shingrix vaccine had a 12% lower risk of cardiovascular events during the first three and a half years after vaccination.

The study, published in Nature Medicine, examines health records over seven years and compares outcomes around the 2017 U.S. shift from Zostavax to Shingrix. Researchers say the approach reduces some of the bias found in earlier studies that simply compared vaccinated and unvaccinated people.

The lower risk includes cardiovascular events such as heart attacks, heart failure and strokes. By the end of the follow-up period, Shingrix is associated with a 4% lower risk of cardiovascular disease.

Dr. Maxime Taquet, a clinical lecturer at the University of Oxford and the study’s lead researcher, says the potential effect could be substantial if confirmed in clinical trials.

“If confirmed in clinical trials, vaccinating older adults against shingles could prevent hundreds of thousands of coronary heart disease, strokes and cases of heart failure worldwide,” Taquet says. “The effect might be enormous.”

Researchers compare new and older vaccines

Shingles develops when the virus that causes chickenpox reactivates in the body. The condition can cause a painful rash and nerve pain that sometimes continues for months or years after the rash disappears.

Zostavax, the first shingles vaccine, became available in 2006 and uses a weakened form of the virus. Shingrix later replaced it as a more effective vaccine and uses recombinant vaccine technology.

Earlier observational studies also report lower cardiovascular disease rates among people vaccinated against shingles. But researchers say those findings may be affected by differences between people who choose vaccination and those who do not.

The new study instead takes advantage of the rapid transition from Zostavax to Shingrix in the United States in 2017. Researchers use the change to compare cardiovascular outcomes among people vaccinated during different periods.

The findings show a relatively small change in absolute cardiovascular risk, but researchers say the potential population-level effect could be meaningful because heart disease and stroke remain major causes of death.

“If confirmed in a randomized controlled trial, the effect of Shingrix would be equivalent to antihypertensives,” Taquet says, referring to medicines used to lower blood pressure.

Clinical trials could confirm the link

Researchers say the study does not prove that Shingrix directly prevents heart attacks or strokes. Randomized clinical trials are needed to determine whether the association represents a true protective effect.

Dr. Hugo Pedder, a research fellow in statistical modeling at the University of Bristol who was not involved in the research, says a randomized trial would provide stronger evidence.

“A randomized trial would be the best way to confidently answer whether recombinant vaccines do provide the benefits seen here versus live vaccines,” Pedder says.

Scientists are also studying why vaccination might influence cardiovascular health. One possibility is that preventing shingles could reduce cardiovascular risks associated with the infection. Another is that the vaccine may affect immune responses involved in inflammation.

Several trials are underway that could provide more definitive evidence. Until those results are available, researchers say the findings should be viewed as promising observational evidence rather than proof that the Shingrix vaccine prevents cardiovascular disease.