Promoting cardiovascular health
In addition, vaccination was associated with a greater relative reduction in stroke risk in younger age groups, lower income groups, and those with diabetes, chronic obstructive pulmonary disease, and anticoagulant use.
Among 2.4 million people observed for the entire study period, vaccination protection increased with the number of vaccines received. People who were vaccinated serially each year had a significantly lower risk of stroke than those who received one shot.
Dr. Holodinsky and colleagues are conducting additional research into influenza vaccination, including stroke risk in children. They’re also investigating whether the reduced risk applies to other vaccinations for respiratory illnesses, such as COVID-19 and pneumonia.
“We hope that this added effect of vaccination encourages more adults to receive the flu shot,” she said. “One day, vaccinations might be considered a key pillar of cardiovascular health, along with diet, exercise, control of hypertension and high cholesterol, and smoking cessation.”
Future research should also investigate the reasons why adults – particularly people at high risk with underlying conditions – don’t receive recommended influenza vaccines, the study authors wrote.
‘Call to action’
Bahar Behrouzi, an MD-PhD candidate focused on clinical epidemiology at the Institute of Health Policy, Management, and Evaluation, University of Toronto, said: “There are a variety of observational studies around the world that show that flu vaccine uptake is low among the general population and high-risk persons. In studying these questions, our hope is that we can continue to build confidence in viral respiratory vaccines like the influenza vaccine by continuing to generate rigorous evidence with the latest data.”
Ms. Behrouzi, who wasn’t involved with this study, has researched influenza vaccination and cardiovascular risk. She and her colleagues have found that flu vaccines were associated with a 34% lower risk of major adverse cardiovascular events, including a 45% reduced risk among patients with recent acute coronary syndrome.
“The broader public health message is for people to advocate for themselves and get the seasonal flu vaccine, especially if they are part of an at-risk group,” she said. “In our studies, we have positioned this message as a call to action not only for the public, but also for health care professionals – particularly specialists such as cardiologists or neurologists – to encourage or remind them to engage in conversation about the broad benefits of vaccination beyond just preventing or reducing the severity of flu infection.”
The study was conducted without outside funding. Dr. Holodinsky and Ms. Behrouzi have reported no relevant disclosures.
A version of this article first appeared on Medscape.com.