A flu shot can reduce the risk of stroke, the study finds
- People over 40 who received a vaccine had a 12% reduced risk of having a stroke
- A study of more than 75,000 people looked at stroke rates in those who received a vaccine
- Previous studies have shown that the flu increases the risk of stroke
Your annual flu shot could protect you from a stroke, a study suggested today.
Spanish researchers compared the health of more than 75,000 people over the age of 40, including thousands who had suffered a stroke.
The results showed that people who received a vaccination had a 12 percent reduced risk of suffering the life-threatening event compared to people who chose not to have their annual top-up.
With flu season lurking just around the corner, experts say the results provide “another reason for people to get their annual flu shot.”
An annual flu shot could reduce your risk of stroke, a study suggested today
Described as “convincing”, the project from the University of Alcalá in Madrid was published online in the journal Neurology.
The study was merely an observational study, meaning the researchers couldn’t prove that the jabs were definitely behind the lower risk.
Other factors could potentially play a role, admitted Dr. Francisco de Abajo and his colleagues.
Previous studies have shown that the flu itself can increase the risk of stroke, suggesting that vaccination may help prevent it simply by preventing people from catching it in the first place.
In theory, however, there could be a separate way the jab works to reduce risk, the team suggested.
More than 100,000 strokes occur in the UK each year, resulting in 38,000 deaths. Around 800,000 people suffer a stroke in the United States each year.
Stroke occurs when either a blockage in a vein or a ruptured vessel prevents blood from reaching the brain.
They are usually triggered by a buildup of cholesterol or high blood pressure, which weaken the arteries and gradually narrow them over time.
dr de Abajo, a pharmacist, said, “It’s very compelling to be able to reduce your risk of stroke with such a simple measure.”
He added: “This observational study suggests that those who have a flu shot have a lower risk of stroke.
“Further research is needed to determine whether this is due to a protective effect of the vaccine itself or other factors.”
All over 50s are to be given a flu shot – as well as another Covid booster – this autumn amid fears the NHS could be crippled by a wave of both viruses later in the year.
The latest research looked at 14,322 people who had ischemic stroke, the most common form. It is caused by a blood clot affecting its flow to the brain.
Scientists compared these to a control group of 71,610 people who had never had a stroke.
They tracked whether patients had received a flu shot at least two weeks before the stroke, or before the same date for those who hadn’t received one.
The results showed that 41.4 percent of stroke victims had received an injection, compared to 40.5 percent of those who had not had a stroke.
Although the risk appeared to be slightly higher in the flu shot group, many patients tend to be older and have high blood pressure and cholesterol, which are major risk factors for stroke.
The final analysis took such factors into account.
THE CAUSES OF THE BLOW
There are two main types of stroke:
1. ISCHEMIC STROKE
An ischemic stroke — which accounts for 80 percent of strokes — occurs when a blood vessel that prevents blood from reaching a part of the brain becomes blocked.
2. Hemorrhagic stroke
The less common, a hemorrhagic stroke, occurs when a blood vessel ruptures and floods part of the brain with too much blood while depriving other areas of adequate blood supply.
It can be the result of an AVM, or an arteriovenous malformation (an abnormal collection of blood vessels) in the brain.
Thirty percent of patients with subarachnoid hemorrhage die before reaching the hospital. Another 25 percent die within 24 hours. And 40 percent of those who survive die within a week.
Age, high blood pressure, smoking, obesity, sedentary lifestyle, diabetes, atrial fibrillation, family history and history of a previous stroke or TIA (a mini-stroke) are all risk factors for stroke.
SYMPTOMS OF A STROKE
- Sudden numbness or weakness in the face, arm, or leg, especially on one side of the body
- Sudden confusion, difficulty speaking or understanding
- Sudden visual disturbances or blurred vision in one or both eyes
- Sudden difficulty walking, dizziness, loss of balance or coordination
- Sudden severe headache with no known cause
Of the approximately three out of four people who survive a stroke, many will have lifelong disabilities.
These include difficulty walking, communicating, eating, and doing everyday tasks or chores.
Both are potentially fatal, and patients must be operated on within three hours or put on a drug called tPA (Tissue Plasminogen Activator) to save them.