Shingles, caused by reactivation of the Herpes zoster virus, is a painful and sometimes serious condition of older age. Earlier studies had hinted that shingles vaccination might also protect the heart, but comparisons between vaccinated and unvaccinated people are vulnerable to bias, because those who choose vaccination differ systematically from those who do not. Oxford researchers found a cleaner natural experiment: the switchover from the older Zostavax vaccine to the recombinant Shingrix vaccine in the United States in October 2017.
Using the TriNetX electronic health records network, the team compared more than 36,000 adults aged 60 and over who received Shingrix with a matched group of the same size who had received Zostavax. Over the following seven years, Shingrix recipients showed a 9 per cent lower overall burden of cardiovascular disease, including a 10 per cent reduction in ischaemic heart disease and a 12 per cent reduction in heart failure, with men also showing a 12 per cent lower risk of stroke.
The findings, published in Nature Medicine and funded by the NIHR Biomedical Research Centre: Oxford Health, add cardiovascular protection to the recombinant vaccine's previously reported benefits against shingles itself and against dementia. The authors are careful to note that clinical trials are needed to confirm the effect and uncover its mechanism, but the result strengthens the case that vaccination policy for older adults may deliver health dividends well beyond its primary target.