Causes and risk factors for strokes
Certain medical conditions are associated with an increased risk of stroke. These include:
- high blood pressure,
- heart conditions such as atrial fibrillation,
- raised blood cholesterol,
- excessive blood loss and
- hereditary blood clotting conditions such as sickle cell disease.
Other factors known to increase the likelihood of stroke are lifestyle factors such as:
- high alcohol intake,
- obesity and
- having an inactive lifestyle.
Stroke is also more common in people of African-Caribbean and South Asian origin, partly because rates of diabetes and high blood pressure are higher in these groups (NHS Choices 2017). The risk of having a stroke also increases with age, “Although most people who have a stroke are over 65, around a quarter of strokes happen in people who are younger,” (NHS Choices 2017). See 'When stroke happens at a young age'.
Some people said how having the stroke had been a complete surprise because they had not known they had high blood pressure or diabetes. Some people felt they had been fit and healthy before the stroke and that it had actually been caused by other conditions, for example heart conditions or a stroke which occurred during a surgical procedure, although very few strokes occur in this way.
- Age at interview:
- Is a married process operator with 2 adult children. Ethnic background/nationality' White/Scottish.
And then, as a result of the operation for the aortic dissection...
...was that' You had the stroke then?
Had they given you any warning that was a risk factor?
No. No. I was lying, on the, on the trolley from the ambulance and having had the tests done, the scans done and that, you see. And the nurse was explaining that you might need to stay in overnight. My wife had, had been called by that time, she was explaining about not getting any meals until midnight and I'd get out a day, you know, 24 hours later, kept in for observation. And it, it transpired that it were a phone call down, you know, 'Get this guy transferred immediately, his aorta was leaking', and the blood from the heart instead of going back through the valves, back through the, you know, the valve, was leaking into my chest cavity. And I was taken to the' [another city] to have an operation. Transferred for the emergency op and that was the Tuesday night and the next thing I remember was the Saturday morning.
Half past 8 on Wednesday morning it was about, when I got back into Intensive Care and it was explained to my wife and family that I might be left with brain damage, kidney damage, liver damage and a stroke. But that was never explained to me, which was maybe a good idea, you know but certainly my wife and family knew of the possible risks that I might be left with these things, including the stroke and it transpired luckily enough it was the stroke I was left with.
- Age at interview:
- Is a married mother with 2 adult children. She is a retired hospital ancillary worker. Ethnic background/nationality' White/Scottish.
The stroke happened during the operation that you had but do you think there's, do you have any ideas about what the cause of your stroke was?
Well, I only go by what they were telling me and they told me that I lost an awful lot of blood during the operation, that I lost an enormous and that my blood pressure dropped right down and that they had to give me I think it was 3 bloods, 3 measures of blood and that same, now one thing I think about, some people say the stroke was going to be inevitable anyway whether, but if it was, I was in the right place when it happened because they were able to treat me at once. Whereas if I had a stroke like that without being in the hospital, I might not have come through but that's the million dollar question.
Lifestyle - alcohol, smoking, diet and exercise.
Some people had been told by their doctor that smoking had been a major cause of their stroke. Others who had given up smoking over 20 years ago or had been light smokers wondered whether this may have contributed but some thought that it probably had not. The risk of stroke declines rapidly after stopping smoking, however even passive smoking is linked to stroke.
- Age at interview:
- Is a married father of 2 adult children and 2 stepchildren. He works as a senior psychiatric nurse trainer. Ethnic background/nationality' White/Welsh.
Obviously you're relatively young to have a stroke. What was your feelings about that?
It was just, well, it was my own fault because I used to be a smoker before I had the stroke. The doctor did say it was probably the smoking that was the main contributory factor so it was a bit of case of I wish I hadn't started but, there we go, you can't turn the clock back.
How do you feel about now that you were a smoker?
Well, I used to enjoy smoking. I knew there was risks involved. So it's not like I was completely in the dark of the risks that I was taking because I knew I was taking risks at the time it seemed like I enjoyed it, so I smoked and that was that. You just take chances, I suppose, in life.
A few people had been heavy drinkers and thought that this in combination with other factors such as smoking, poor diet and stress had contributed to them having a stroke.
- Age at interview:
- Is divorced with no children and he is a retired dustman/ retained fire-fighter. Ethnic background/nationality' White/Scottish.
Thinking about the cause of your stroke, what do you think was the cause of your stroke?
Well, I personally I think I was, because I used to be an awful drinker and I think drink and smoking was the main cause.
And how do you feel about that now? You know, now it's all happened?
Well, I don't drink now except maybe every 3 months, 2 or 3 months I'll maybe have a bottle of red wine. And use the whole lot that, that night, drink the bottle and finish it that night, and that's it. I'll not touch it again for about another 3 months. And the smoking, I don't smoke at all now. And yet I was smoking 60 to 80 a day before I took this stroke.
High fat diet, being overweight and lack of exercise were often seen as contributing to the stroke. People realised that high fat diet can be linked to high cholesterol but some were not aware that you do not have to be overweight to have raised cholesterol. High cholesterol is sometimes hereditary.
- Age at interview:
- Is a married father of 2 adult children and retired charity worker. Ethnic background/nationality' White/English.
So the blood pressure, was that the cause of the stroke?
That was the cause of the stroke. High blood pressure, high cholesterol in fact I had to have a management check-up annually for my health, for my job. And I had the management check-up, found that my blood pressure was through the roof, I take, I took 1 tablet, I was given a series of tablets to take. I took 1 tablet and the day after I'd taken that tablet, I had a stroke. I won't blame it on the tablet obviously but and my blood pressure was too high, my cholesterol was too high, I was an accident waiting to happen. I mean my eating habits were terrible. I would come home from work, I would have a large lump of cheese when I came home, I'd have a bag of crisps, I'd then have my evening meal and I'd eat chocolates and biscuits during the evening.
Two people had been abroad in a hot country and wondered whether their strokes had been partially due to over activity and dehydration.
Not getting health checked
A few people thought that not seeing their doctor and getting their health checked had been responsible for them having a stroke. Men in particular felt that this was a common male failing although women also said that they should have had their health checked.
- Age at interview:
- Is a widowed retired legal secretary with no children. Ethnic background' White/English.
They checked my blood pressure probably 2 or 3 times a day for those, first 2 weeks but they didn't actually do anything to me at all. I think they, for the first, I've heard this since, the first couple of weeks, I think you have to sort of stabilise so they really just leave you. I didn't have any medication at all. I had nothing. They just watched me, just kept a check and then I think I had a, I think before I left the hospital I had another scan. I suppose they just check to see how things are getting on up there, you know, whether there's any, any more bleeding or anything and, and then I was transferred to the rehabilitation unit and I was assessed by the doctor who's in charge at the unit and that's when I started taking blood pressure pills, I started losartan and then they were trying to stabilise my blood pressure because that was the cause of my stroke and obviously that is a problem. Maybe I've had for a long time, I don't know because I never went to the doctor and I never had checks, so I didn't know that my blood pressure was high because I didn't have any symptoms so it could have been something that I've suffered with for many years and never found out about. So that obviously was a problem.
They were trying to get my blood pressure down and the dose of losartan that I was having obviously wasn't really doing the trick so I went on to bendrofluazide, which is a water tablet as well as blood pressure and gradually, I mean, they checked me, they used to check my blood pressure all the time there in the rehab, I suppose because you're having physio and you're doing all sorts of things. So it was checked all the time. They did have problems with getting it down I know. It seemed to be a big problem and since I've, since I've been out of hospital my doctor has always said that it was my responsibility to keep my blood pressure checked and that's something that I told in hospital, friends came to visit and I said, 'Well, I've never had my blood pressure checked, I've never felt any need to have it done' and I said, 'That is something you should all go and do immediately, get a blood pressure check' because it's like a sort of silent killer. You don't know, it just creeps up on you and if you don't have checks, you don't know, so I said and every, and everybody was going to rush home and go out and get blood pressure checks, which I just think if a very good thing. I think they, it's something that should be sort of impressed on everyone.
One man, who had suffered a heart attack a few years earlier, regretted that he had not changed his lifestyle or attended follow up visits and felt that this was a major reason for his stroke.
- Age at interview:
- Is a married father of 2 adult children and a retired civil servant. Ethnic background' White/Scottish.
The cause of the stroke was my fault. No doubt about that. It was my fault. As I say, I had a heart attack 12 years ago. I went to the doctors and'I always felt doctors were, once they got hold of you, that was it, they never let you go. So any letters I got to come to the doctors for my, a test or whatever, I would ignore, you know, things like that. I wouldn't go to the doctors if I had a heavy cold or a heavy flu or aches or pains. I would, my doctor would be the last person I would go and see. OK. I might be frightened of doctors but it was the last person, as long as I was able to get about, I was quite happy not to go to the doctors. They did send me letters to go to the Heart Clinic. I didn't go because I was frightened again they might find something wrong. I might, stop me doing what I was doing. I wouldn't go.
So I blame nobody but myself for my stroke, you know. I mean, I don't say it's anybody fault but my own. If my lifestyle had been better, I wouldn't have had a stroke and, as I say, now I'm doing everything I possibly can to avoid further possible trouble. I go to the doctor every 3 months for check-ups, they take my blood pressure every week through the computer, keep eating my diet. I mean, my wife the chip pan's out, the frying pan's out, things like that, you know, and I take my tablets, no more smoking. My drinking, I don't bother drinking any more. I would say if I didn't get a pint of beer again, it wouldn't bother me. Honestly. I like the company. Don't get me wrong. I'll go out sometimes on a Friday night with the lads and I like their company, I like the patter but the beer doesn't, maybe 2 pints, that's it. The beer doesn't bother me but the lads are good. And my family have been, they've been really good.
High blood pressure
High blood pressure is a common cause of stroke. Whilst some people had been aware that they had high blood pressure others had not been aware because there were often no symptoms. They encouraged other members of their family and friends to get their blood pressure checked particularly if they were over 50.
The wife of a man of south Asian origin explained that high cholesterol and high blood pressure ran in the family and that her brother who is a doctor had advised her husband's family to get checked as they may also be at risk of stroke.
- Age at interview:
- He is a married father with 1 child. He works as an accountant. Ethnic background/nationality' Srilankan/English.
Wife' Yeah. I think it is hard. Before we, I would tell the other people, before something happens, you have to be look after your health first, you know. You have to help, at least you have to go for the regular check-up. Like [my husband's] family, they all have this cholesterol problem or high blood pressure. It's a family hereditary. My brother advises as a doctor, he advise every 6 month his family need to go for the check-up, every 6 month they have to have a blood pressure test and a cholesterol test as well. So something happen after that, we can't bring him back as 100 per cent as we possible but we try to avoid other stroke. We can prevent but we can't do anything about it, yeah, and we have to be, whoever look after the person need to be patient. Time is the healer, I think so.
Some of the people that we spoke to had close relatives who had also had a stroke and wondered whether there may be a genetic link. Stroke does run in families and some specific genetic conditions can also cause stroke e.g. sickle cell disease.
One young woman that we spoke to had a rare clotting disorder called Factor V Leiden - her father and cousin also have the condition and now take medication to prevent a stroke. She thought that smoking and taking the pill may have increased her risk of having a stroke. Another woman who had a brain haemorrhage due to arterial venous malformation, which is sometimes hereditary, worried that other people in her family may be at risk.
Some people thought that having a stressful job or busy lifestyle had contributed to their stroke. Others wondered whether their stroke had been triggered by a specific stressful event. Strokes can very occasionally be caused by one off stressful events but the long term impact of stress on the risk of stroke is not clear and the effects may be due the links between stress and lack of exercise and other high risk lifestyle factors.
Heart and other vascular conditions
Blood clots that cause a stroke sometimes originate because of heart conditions or during operations on the heart, such as bypass operation or repair of a heart valve.
A few people had been found to be suffering from a condition known as atrial fibrillation where changes in the electrical conducting system of the heart cause it to beat irregularly (arrhythmia). In the general population this is quite common and is a considerable risk factor for stroke. The erratic blood flow can lead to clots which can become lodged in the blood supply to the brain.
- Age at interview:
- Is a married mother and has 2 adult children. She works as a temporary legal secretary. Ethnic background/nationality' White/English.
I've had, I had wonderful treatment, I had an appointment then to go back to the Stroke Clinic, the Outpatient Stroke Clinic on March the 3rd and they explained that they thought the stroke was the result of a blood clot, that I'd got , they thought it was caused by an unusual heart beat and this can cause clots to go from your heart to your brain and they suggested I went on warfarin, you know, you don't have to but, you know, the choice is yours but it would reduce by two thirds the chance of you having another stroke. So I thought I'd be mad not to.
A few people had a stroke or TIA due to a narrowing of the arteries of the neck (carotid arteries) due to atherosclerosis (furring up of the arteries). One woman, however, thought that a vigorous neck massage precipitated clotting in her carotid artery, and another woman had been told that this type of stroke can occur because of a sudden jerk to the neck. These are relatively rare causes of stroke.
Last reviewed June 2017.
Last updated June 2017.