Tejal Somvanshi
New research suggests that receiving a recombinant shingles vaccine may reduce cardiovascular disease risk in older adults. A study published in Nature Medicine tracked 72,920 matched individuals and found those receiving the recombinant vaccine experienced significantly lower rates of heart disease and stroke over seven years.
The study compared two matched cohorts of 36,460 adults each. The 2018 cohort had 93.5 percent exposure to Shingrix, the recombinant zoster vaccine. The 2017 cohort had 98.6 percent exposure to Zostavax, the live-attenuated vaccine. Both vaccines prevent shingles, but their effects on cardiovascular outcomes differed substantially in this population.
Over seven years, people who received Shingrix showed a 9 percent lower cardiovascular disease burden compared to those who received Zostavax. The cardiovascular benefits included a 10 percent reduction in ischemic heart disease, a 12 percent reduction in heart failure, a 12 percent reduction in ischemic stroke among men, and a 7 percent reduction in atrial fibrillation.
Scientists propose that the recombinant vaccine’s specific composition triggers different immune responses than the older live-virus version. However, researchers explicitly noted that causal inference requires additional assumptions and that unmeasured factors cannot be excluded as contributing to the differences observed. The study authors explicitly called for clinical trials and mechanistic studies to better understand the mechanisms behind the observed cardiovascular differences.
In the United States, Shingrix is currently the available shingles vaccine for older adults. Zostavax was discontinued by its manufacturer Merck and officially withdrawn from clinical use on November 18, 2020, making the study’s comparison between the two vaccines an analysis of the historical transition period between vaccine types.
This finding matters because cardiovascular disease remains a leading cause of death and disability. Adults over 50 who receive shingles vaccination should understand that the cardiovascular benefits documented in this study occurred over a multi-year period in a large matched population, not necessarily in every individual who receives the vaccine.
