Can Yoga Cause a Stroke?
There are two main types of stroke. In a hemorrhagic stroke, a blood vessel ruptures and bleeds into the brain tissue. Recently I posted a response to a reader’s question regarding the risk of bleeding in the brain with sirsasana.
In an ischemic stroke, blood clots inside a vessel and deprives the surrounding brain tissue of further blood flow and oxygen. Sometimes that clot occurs outside the skull, and then a piece of it breaks off, traveling in the blood stream to the brain where it causes damage.
In 2009, the International Journal of Yoga Therapy published the results of a survey that was sent out to 33,000 Yoga teachers and therapists around the world. Of the 1,336 people who answered, four reported that the worst injury they had ever seen with Yoga practice was a stroke.
There was confusion about those four strokes though. It wasn’t clear from the returned questionnaires that the strokes occurred from Yoga rather than that the students were trying to recover from a previous stroke with Yoga. It also wasn’t clear if there was a medical diagnosis of a real stroke. Some conditions, like migraine headaches, can mimic stroke symptoms. Were they hemorrhagic or ischemic? Was there an underlying diagnosis of high blood pressure? What asanas or movements might have precipitated the symptoms? All of these are unknown.
A review article published in the New England Journal of Medicine in 2001 reported on strokes caused by dissection of the carotid and vertebral arteries. The two carotids in front and the two vertebral arteries in back of the neck are how the brain gets its blood supply. In a dissection, there’s a tear in the inner lining of the blood vessel wall. Then, under pressure from the pumping action of the heart, blood pushes through that small tear in the lining and goes in between the layers of the vessel wall. There’s nowhere for it to go, so it stagnates and forms a clot that pushes the inner wall outward into the lumen of the blood vessel, eventually blocking the flow of blood through the lumen and depriving the brain of oxygen and nutrients.
Why is it relevant to Yoga? Because most dissections are thought to arise from minor trauma. There’s a something called “beauty-parlor syndrome” in which women have suffered vertebral artery dissections and strokes from extending their heads backwards and rolling them from side to side while in extension during shampooing. Anyone who’s been to the hair salon can understand exactly what’s being described. The motion of full extension of the neck with rolling it around can trap the vertebral arteries that run within the cervical bones. If they get caught or snagged on a bone fragment and then stretched, a tear in the inner lining of the blood vessel wall can occur – and then dissection and stroke.
Carotid and vertebral artery dissections account for only 2% of ischemic strokes, but their incidence is highest in the young and middle-aged and can even occur in children. Seventy percent occur between the ages of 35 and 50. In only 6% to 10% of dissections, there is an underlying connective tissue disease or family history. There’s no clear association with high blood pressure.
Concerns about the possibility of dissection and stroke resulting from Yoga practice surfaced in the early 1970s. Since then only a handful of cases have been reported in which Yoga was hypothesized to be the cause. There’s no way to be certain that Yoga movements precipitated the events.
It’s difficult to say exactly what specific activity causes an arterial dissection leading to a stroke. Most often, the stroke symptoms do not occur immediately after the instigating movements. It takes some time for the blood to flow inside of the blood vessel wall and for it to expand enough to block significant blood flow in the lumen. It may take several hours up to a few days. This lag time makes it difficult to assign a specific movement as a cause of the dissection. Many patients don’t remember extending and rotating. Others do. Dissections have occurred when people were painting the ceiling, being manipulated by the chiropractor, playing volleyball, and drinking quick shots of liquor by throwing their heads back.
More research focusing on both the beneficial and potentially injurious aspects of Yoga is being carried out. For now, there’s not much data on the risk of stroke with Yoga practice, but three areas of caution are advised.
- Avoid full extension of the neck, particularly with rotation from side to side, as this may led to snagging of a blood vessel on bone resulting in vertebral artery dissection and stroke.
- If there is a significant family history of cerebral aneurysm, be sure to check with your physician prior to practicing inverted postures. She may want to do an MRA test to visualize the blood vessels in your head.
- If you haveuncontrolled high blood pressure, avoid inverted Yoga postures. With Yoga and hypertension, it’s best to work with your teacher and your physician to determine what is safe for you.
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13 Comments to “Can Yoga Cause a Stroke?”
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I am finishing up a book about yoga and need statistics or quotes about the dangers of doing some yoga poses like headstand, plow and forward bends. I have invented a style which eliminates these poses and focuses on positions we use in real life functions. Any help is appreciated as I think that injuries both long and short term are much higher than is being reported. Thank you, Michaelle Edwards, hanalei kauai
I have had an mri, it showed normal except “small to moderate sized developmental venous anomaly of the right temporal lobe” do you think it is safe for me to do yoga?
56 female
Controlled high blood pressure
Thank you for your time
Dear Susan,
Developmental venous anomalies rarely cause any problems for people. They are usually incidental benign variants found on an MRI done for totally unrelated reasons. So many more MRIs are getting done these days that we’re finding they are much more common than previously thought.
I don’t know your full medical history and we haven’t had a chance to develop a personal doctor-patient relationship, so I can’t give you specific advice.
I will say that if I had this exact same reading on a scan, I would continue to practice Yoga and to keep my blood pressure under control. Although it is unlikely to be a problem, to be on the safe side, I wouldn’t do the headstand – at least not often or for very long – but I don’t do much of that anyway because it can be hard on the neck.
Hope that helps.
All the best,
Kathleen
If I have done damage to an artery would I be in pain? I don’t do yoga but strange sharp pains in the back of my head sometimes occur.
Dear Alex,
Please see a doctor to diagnose your condition. In general, arterial damage in the back of the neck does not cause sharp pains.
All the best,
Kathleen
so what are the symptoms? or are there none until it’s too late?
There can be a constellation of different symptoms depending on exactly where the vertebral dissection takes places along the course of the artery, whether it extends into the head, etc. The most typical presentation is an extremely severe headache localized to the back of the head and neck with some neurological findings suggestive of posterior circulation malfunction. These findings generally include the sudden onset of some variable combination of:
numbness and tingling on one side of the face
difficulty enunciating and pronouncing words properly
loss of temperature sensation on one side of the body
loss of taste on half the tongue
sustained hiccups
dizziness (spinning sensation)
nausea and vomiting
double vision or image movement experienced with head motion
trouble swallowing
balance problems
hearing loss on one side
I had a stroke a year ago, at age 43. cause undetermined. what does “full extension of the neck, particularly with rotation from side to side,” mean. And how do u avoid this in yoga. I do yoga, along with other regula group exercises.
thx,
Deana
Deana,
I’m sorry to hear about your misfortune. Sadly, early 40s is the most common age to have a posterior circulation stroke – such a young age.
It’s okay to put the head back to look up at the ceiling, but completely dropping the head backwards so that you’re trying to look at the wall behind you (just from a neck movement) is “full extension.” I’ve had Yoga teachers tell me to do the latter, and it’s not safe.
Some Yoga teachers and programs also recommend rolling the head from side to side or around in full circles. Forward rolls are okay, but rolling the head while looking up at the ceiling (or even further extending the neck) is not safe. That’s what I meant by “rotation from side to side.” I see now that wasn’t very clearly worded. Thanks for pointing that out.
Wishing you all the best,
Kathleen