Getting the flu shot may be more important than ever — a study suggests it can lower your risk of stroke years later.
Health officials should push everyone to get regular flu shots, not just the most vulnerable, researchers say.
The study analyzed health data from more than 4 million adults in Alberta, Canada over a 10-year period.
The results showed that people who got the flu shot once a year or every flu season reduced their risk of stroke by more than a fifth over a 10-year period.
The protective effect was sharper in men and young adults.
Researchers haven’t investigated why getting the flu vaccine significantly lowers the risk, but the prevailing hypothesis is simple.
The vaccine reduces the risk of getting and getting sick with influenza, which is a known risk factor for stroke.
Getting the flu shot may be more important than ever — a study suggests it can lower your risk of stroke years later
People who received the flu vaccine once a year or during each flu season over a 10-year period reduced the risk of stroke by about 23 percent among all adults.
Causes of stroke
There are two main types of stroke:
1. ISCHEMIC STROKE
About 80 percent of strokes are ischemic strokes – when there is a blockage in an artery that prevents blood from reaching a part of the brain.
2. Bleeding problem
In very rare cases, a hemorrhagic stroke occurs when a blood vessel bursts, flooding part of the brain with too much blood and depriving other areas of its blood supply.
It can be the result of an AMI or arteriovenous malformation (abnormal clustering of blood vessels) in the brain.
About 30 percent of people with subarachnoid hemorrhage die before reaching the hospital. Additionally, 25 percent die within 24 hours. And 40 percent of survivors die within a week.
Age, high blood pressure, smoking, obesity, sedentary lifestyle, diabetes, atrial fibrillation, family history, and previous history of stroke or TIA (miniature stroke) are all risk factors for stroke.
- Sudden numbness or weakness of the face, arm or leg, especially on one side of the body
- Sudden confusion, difficulty speaking or understanding
- Sudden loss of vision or blurred vision in one or both eyes
- Sudden trouble walking, dizziness, loss of balance or coordination
- Unexplained sudden severe headache
Approximately three out of four people who survive a stroke, many have lifelong disability.
This can include difficulty walking, communicating, eating, and completing daily tasks or household chores.
Both are potentially fatal, and patients need surgery or a drug called tPA (tissue plasminogen activator) within three hours to save them.
Dr Michael Hill, lead study author at the University of Calgary, said: ‘We wanted to see if the vaccine had the same protective properties in people at risk of stroke.
‘Our findings show a lower risk of stroke among people who have recently received the flu vaccine. This was true for all adults, not just those at high risk of stroke.’
The researchers looked at patient records using administrative data from the publicly funded Alberta Health Care Insurance Plan.
Scientists say it’s the largest flu vaccine and stroke risk study to date.
The overall risk reduction was about 23 percent for all adult-aged individuals, men and women.
But the reduction was greater in men than in women – 28 percent and 17 percent – and stronger among young people.
The researchers believe that the lower relative risk reduction in the elderly may be related to a reduced biological response to vaccination with aging.
The immune response to vaccines in the elderly is reduced compared to young and healthy adults.
Older people are also more likely to have a stroke.
Previous studies have shown that catching and being sick with the flu increases the risk of stroke and other heart problems.
The scientists found that the incidence of stroke increased three weeks after a flu case.
The immune response to the flu causes the blood to thicken and inflame the arteries, making people more prone to clots.
“There’s a long history between infections and stroke — upper respiratory tract infections are associated with stroke — so it was natural to start looking at this,” Dr. Hill said.
‘There is a link between influenza and heart disease – heart attacks – and drawing the link with stroke was a natural next step.’
It was the study. Published Earlier this week in The Lancet Public Health.
A stroke occurs when blood flow to the brain is interrupted or cut off.
Stroke is the leading cause of disability in the United States. Stroke victims often experience paralysis, loss of movement, and speech impediments.
Although stroke is treatable, time is of the essence.
The sooner a stroke victim seeks medical attention, the more effective medications can be to restore blood flow to the brain and reverse damage.