Getting a flu jab may cut your risk of a stroke, study finds
- People aged over 40 who received a jab were 12% less likely to suffer a stroke
- Study of more than 75,000 people looked at stroke rates in those who got a jab
- Previous studies have shown that getting the flu increases the risk of a stroke
Getting your annual flu vaccine could protect you from a stroke, a study suggested today.
Spanish researchers compared the health of more than 75,000 over-40s, including thousands who had suffered a stroke.
Results showed people who had received a jab were 12 per cent less likely to suffer the life-threatening event, compared to people who decided against getting their yearly top-up.
With flu season lurking just around the corner, experts said the findings provide ‘yet another reason for people to get their yearly flu shot’.
Getting an annual flu vaccine could reduce your risk of having a stroke, a study suggested today
The University of Alcalá in Madrid project, described as ‘compelling’, was published online in the journal Neurology.
The study was merely observational, meaning researchers could not prove the jabs were definitely behind the lower risk.
Other factors could potentially be at play, Dr Francisco de Abajo and his colleagues admitted.
Previous studies have shown the flu itself can raise the risk of a stroke, suggesting jabs may simply help prevent them by stopping people from getting infected in the first place.
But there could, in theory, be a separate way that the jab works to cut risk, the team suggested.
More than 100,000 strokes occur every year in the UK, resulting in 38,000 deaths. Around 800,000 suffer a stroke annually in the US.
Strokes occur when either a blockage in a vein or burst vessel stops blood reaching the brain.
They’re usually triggered by a build up of cholesterol or high blood pressure, which weaken arteries and gradually narrow them over time.
Dr de Abajo, a pharmacist said: ‘To be able to reduce your risk of stroke by taking such a simple action is very compelling.’
He added: ‘This observational study suggests that those who have a flu shot have a lower risk of stroke.
‘To determine whether this is due to a protective effect of the vaccine itself or to other factors, more research is needed.’
All over-50s are set to receive a flu jab — as well as another Covid booster — this autumn amid fears the NHS will be crippled by a surge of both viruses later in the year.
The latest research looked at 14,322 people who had an ischemic stroke, the most common type. It is caused by a blood clot affecting flow to the brain.
Academics matched these with a control group of 71,610 people who hadn’t already suffered a stroke.
They tracked whether the patients had received a flu jab at least two weeks before the stroke, or before that same date for those who did not suffer one.
Results showed 41.4 per cent of stroke sufferers had received a shot, compared to 40.5 per cent of those who hadn’t had a stroke.
Although the risk appeared slightly greater in the flu jab group, many patients tend to be older and have high blood pressure and cholesterol, which are key risk factors for a stroke.
The final analysis took into account such factors.
THE CAUSES OF STROKE
There are two major kinds of stroke:
1. ISCHEMIC STROKE
An ischemic stroke – which accounts for 80 per cent of strokes – occurs when there is a blockage in a blood vessel that prevents blood from reaching part of the brain.
2. HEMORRHAGIC STROKE
The more rare, a hemorrhagic stroke, occurs when a blood vessel bursts, flooding 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 arteriovenous malformation (an abnormal cluster of blood vessels), in the brain.
Thirty percent of subarachnoid hemorrhage sufferers die before reaching the hospital. A further 25 per cent die within 24 hours. And 40 per cent of survivors 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 having a stroke.
SYMPTOMS OF A STROKE
- Sudden numbness or weakness of the face, arm or leg, especially on one side of the body
- Sudden confusion, trouble speaking or understanding
- Sudden trouble seeing or blurred vision in one or both eyes
- Sudden trouble walking, dizziness, loss of balance or coordination
- Sudden severe headache with no known cause
Of the roughly three out of four people who survive a stroke, many will have life-long disabilities.
This includes difficulty walking, communicating, eating, and completing everyday tasks or chores.
Both are potentially fatal, and patients require surgery or a drug called tPA (tissue plasminogen activator) within three hours to save them.