There may be a big benefit to getting your flu shot beyond virus protection, according to a new observational study published in the journal American Academy of Neurology.
The study found that people who received the flu shot were less likely to have a stroke. Specifically, the study focused on ischemic stroke, which “accounts for about 87% of all strokes,” according to the American Heart Association, and happens when blood flow to the brain is blocked.
The 14-year study took place in Spain and followed 14,322 people who had suffered a stroke. Each person was compared with five people of the same age and sex who had never had a stroke. All subjects were between 40 and 99 years old.
Researchers compared the date of the stroke with the date of the flu shot to see if participants had received their vaccination at least 14 days before the stroke. They also looked at this time frame in people who did not have a stroke.
About 41.4% of people who had a stroke during the study period received the flu shot compared with 40.5% of people who had not had a stroke. However, after adjustment for problems such as vascular-related conditions (people in the vaccinated group tended to have more stroke risk factors, such as high blood pressure or cholesterol), it was found that those who got their annual flu shot were 12% less likely to have a stroke than those who didn’t get the vaccine.
Experts aren’t quite sure why your flu shot might reduce your risk of stroke.
The exact reasoning behind this positive outcome is unclear at this time, but researchers have some theories. Study author Dr. Francisco José de Abajo told Medical News Today that “we can only speculate about the mechanisms at this stage, but there is several evidence from previous studies … suggesting that flu vaccination may reduce inflammatory mediators.”
And according to the American Heart Association, “systemic markers of inflammation have been shown to be risk markers for stroke.” Thus, the reduction in inflammation could be the reason behind this reduced risk of stroke in study participants.
In addition, not all vaccines lead to a reduced risk of stroke — the pneumonia vaccine didn’t have the same effect, researchers found, leading them to believe there is a link between the flu vaccine and a lower risk of stroke.
That said, the new study has some limitations. It was observational and did not look at other factors, such as diet and exercise, in the subjects’ daily lives. Fitness, a nutritious diet and a healthy weight all contribute to a lower risk of stroke. It is possible that people who are more likely to receive a vaccine are also adopting good health practices in other areas.
Either way, getting your flu shot is important.
The flu shot is an important way to protect yourself and those around you from contracting the virus. According to the Centers for Disease Control and Prevention, the flu kills tens of thousands of people each year and infects more than 9,000,000 people each year.
While many people can fight off the virus, it is a very risky disease for the elderly, young children and those with illnesses, such as asthma and COPD, Dr. Bert E. Johansson, a vaccine expert with the National Hispanic Medical Association, previously told HuffPost.
By getting the flu shot, you lower your risk of developing the virus, protect your loved ones — and possibly even lower your risk of stroke.
“These results are another reason for people to get their annual flu shot, especially if they have an increased risk of stroke,” de Abajo said in a statement. “To be able to reduce your risk of stroke by taking such a simple action is very compelling.”