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Stroke: The Basics

By Rhoda Frost

Photo credit: Pixabay

Stroke is one of the leading causes of death worldwide,[1] resulting in around 5.7 million deaths each year due to first-time strokes.[1] As a disease known to be a medical emergency requiring immediate intervention and treatment, it has already been the subject of nationwide awareness campaigns. However, there is surely still more that can be done to increase public knowledge, particularly in a disease which can be so debilitating, and in which rapidity of treatment is so important. So, do we really understand what a stroke is, and what its warning signs are? Do we know what action to take if someone has a stroke? This article will attempt to address all these points.

What is a stroke?

First things first – what actually is a stroke? Well, there are many different types of stroke, all caused by different underlying factors, but they all result in the removal of oxygen from at least one part of the brain. This can be due to a blockage in an artery which the blood cannot flow past – an ischaemic stroke, or due to a bleed in the brain – a haemorrhagic stroke.[2] The severity of the stroke, and the severity of the symptoms the sufferer experiences, depends on the size of the artery that has been blocked or that has bled – the larger the artery, the greater area of the brain it normally supplies with blood, and thus the greater the area that will become deprived of blood, and therefore oxygen. As almost all of our bodily functions, both conscious and unconscious, are controlled by the brain, this lack of oxygen to the brain translates into a loss of different functions, such as speech and motor control. Stroke prognosis (the long-term outcome of the disease) is also very time-dependent; treatments are much more effective the sooner they are given after the stroke starts.[2] This is because the sooner the treatments are given, the sooner the blood flow can be restored to the affected area, and the less permanent damage will be done. This is also why public awareness is so important, so stroke can be recognised as a medical emergency.

Risk factors

There are many different risk factors for stroke, the most important of which is age. The frequency with which stroke occurs increases with age,[1] and as the population of many countries, including the UK, is getting older on average, stroke is anticipated to become an even greater burden in the years to come.[3] Other important risk factors include family history, hypertension (high blood pressure), smoking, diabetes, cardiac abnormalities, obesity, metabolic disorders, various diseases, and previous history of stroke or TIA (see below).[2] Many of these risk factors are modifiable; something can be done about them. This is really key in stroke prevention, as it is clearly far better to prevent a stroke from happening in the first place, than to have treatment once it has already occurred. It is therefore important to make sure we have a healthy lifestyle, and avoid habits like smoking, in order to reduce the possibility of having a stroke, or other related diseases.

Photo credit: Pixabay

So, what’s a TIA?

TIA stands for Transient Ischaemic Attack. The main difference between a TIA and an ischaemic stroke is the timing – any functional problems as a result of a TIA last less than 24 hours, whereas in a stroke they last longer than 24 hours.[4] The mechanism of how they both occur is essentially the same, as a result of a blockage in an artery leading to a lack of blood flow to the tissue.

It has been well established that the risk of stroke is considerably raised after a patient has had a TIA; some studies have suggested by as much as 10 % in the week after a TIA.[5] However, the brief and vague symptoms often experienced during an episode can result in patients not seeking medical attention, or even in medical professionals not identifying the TIA for what it really is. It has been shown that if medical attention is sought after a TIA, and a combination of interventions used, then the risk of repeat episodes could be reduced by around 80 %.[6]

Photo credit: Pixabay

Signs and symptoms

Since a TIA can have quite non-specific symptoms, and since medical professionals can misdiagnose them, how can the public be sure of the symptoms of a TIA or stroke? This can be difficult, but due to the potential severity of stroke, if any stroke-like symptoms occur then it’s better to seek medical help anyway, rather than to run the risk of long-term damage. There can be a wide variety of stroke symptoms, depending on the territory of the brain which is deprived of oxygen, but there are still some key things to look for.[2] Firstly, a stroke will generally be localised to one side of the brain, meaning that weakness may occur on one side of the body, often in the face or limbs. The stroke victim may not be able to walk properly or perform other tasks such as holding their arms level in the air, and their face may be slumped on one side. There may also be some confusion, where they are unable to understand speech or what is happening to them. There can be a change in their own speech too, where they may say things that make no sense, or where they have trouble actually forming and saying words. In a stroke, all of these changes will have a very acute, sudden onset. If any of these symptoms are seen, then emergency services should be contacted as soon as possible, to minimise the delay in getting treatment.

Public awareness

If it is so important to be treated as soon as possible, it seems reasonable that the public should be well educated about what stroke looks like, and what to do if one occurs. Probably the most famous and well-known public awareness campaign was the FAST campaign, which ran on UK television in several phases between 2009 and 2013. FAST stands for Face (has the face drooped on one side?), Arms (can the person hold both their arms out straight, or does one drift downwards?), Speech (is their speech slurred or incomprehensible?) and Time (time to call 999). This system could potentially identify around 90% of strokes,[7] with an acronym that is easy to remember. After the campaign ran, studies have shown that patients were more likely to seek emergency help in the event of a stroke, and were more likely to arrive at hospital within 3 hours of when symptoms started.[8] Knowing and being able to spot these signs of stroke could make all the difference in the outcome for a friend or loved one who suffers a stroke.

What to do

So, if you follow the FAST campaign’s recommendation (and you should), then the appropriate action to take if you identify any one of these symptoms in yourself or a friend, relative, or even just a person on the street, is to call 999 as soon as you can, and tell them that a stroke is suspected. This is the best way to get the appropriate care, and to get the best chance of a full recovery.

Conclusion

To sum all this up…Stroke is serious. It’s on the rise as we get older as a nation, and its symptoms can be non-specific and hard to recognise. However, with acronyms like FAST, and the knowledge that time is so important in this disease, we need to be vigilant in looking for these symptoms of stroke, and to be motivated to call the emergency services if we identify any of them.


References

  1. A. Di Carlo, Age Ageing, 2009, 38, 4-5
  2. S. Adriance et al., “The Stroke Book”, 2nd ed, 2013, Cambridge University Press
  3. P. M. Rothwell, et al., Lancet, 2004, 363, 1925-1933
  4. S.T. Pendlebury, M.F. Giles, P.M. Rothwell, “Transient Ischaemic Attack and Stroke: Diagnosis, Investigation and Management”, 1st ed, 2009, Cambridge University Press
  5. P. M. Rothwell et al., Lancet, 2007, 370, 1432-1442
  6. D. G. Hackham, J. D. Spence, Stroke, 2007, 38, 1881-1885
  7. D. O. Kleindorfer et al., Stroke, 2007, 38, 2864-2868
  8. F. J. Wolters et al., Int J Stroke, 2015, 10, 1108-1114

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