11 causes of strokes
Adapted from a blog originally written for Kinetik WellBeing by Dr Stephens.
A stroke is a potentially life-threatening medical emergency that happens when there is an interruption in the blood supply to part of the brain.
Stroke causes
There are multiple possible causes of strokes. Research has shown a link between the following causes and ischemic strokes (caused by a blood clot)(1)
1. Diabetes
2. Atrial Fibrillation (a type of irregular heart beat that can cause turbulence in the blood stream and increase the chance of a blood clot forming)
3. Previous heart attack
4. Previous stroke
5. Intermittent claudication (a disease characterised by calf pain that happens on walking, due to problems with the arteries in the legs)
6. Other causes of atherosclerosis (unhealthy narrowing of the arteries), such as high cholesterol levels and obesity(2)
The following causes were found to be linked with hemorrhagic strokes (caused by a bleed in the brain rather than a clot; also, typically more severe):
7. Smoking
8. Excess alcohol consumption
Lastly, these causes had a strong connection to both types of stroke:
9. Advanced age
10. Female Sex
11. Hypertension (high blood pressure)
It’s truly a case of ‘last but not least’, as hypertension is actually the biggest risk factor overall for both stroke and cardiovascular disease and probably causes about half of all strokes(3).
Are strokes hereditary?
Unfortunately, if someone in your family has had a stroke, the risk of you having one goes up. Certain people groups appear to be at increased risk also, in particular, people with South Asian, African and Caribbean ethnicities. This may be due to these groups of people having higher rates of diabetes and high blood pressure(2). Fortunately, regardless of what risks you’ve inherited, there are almost always steps you can take to bring this risk down.
Preventing Strokes
High blood pressure is the number one risk factor for stroke, and it is also very common - about half of US adults have hypertension, although 1 in 5 are unaware they have it and only 1 in 4 have it under control(4). If you have not checked your blood pressure recently, please get this done as a priority. Use our blood pressure calculator(5) to see if your blood pressure puts you at risk.
After this, it can be useful to think about preventing strokes based on whether you have had one already (secondary prevention) or not (primary prevention).
Primary Prevention
This involves taking a pro-active approach by looking at what risk factors you have, and making changes to your lifestyle and/or medication to mitigate these risks as best as possible. To summarise the modifiable risk factors, these include:
Smoking: Visit the Colorado Quit Line (6) for free support in becoming smoke-free.
Excess alcohol consumption: There is support(7) available if you’d like it.
Obesity
Medical conditions, such as Hypertension, Diabetes, Hyperlipidemia and Atrial Fibrillation.
If you don’t know your cholesterol and average sugar levels, if you are overweight or would like support in reducing alcohol or cigarettes, please speak to your Primary Care Provider.
An important point to make here is the benefit of physical activity: while it is obvious how being more active can modify some of the above risk factors (e.g. reducing obesity, improving cholesterol ratios, lowering blood pressure), there is also evidence that the impact of higher intensity of physical activity in preventing stroke goes even beyond this(9)).
Secondary Prevention
If you’ve had a stroke already, the first step in preventing a second one is typically to assess for the above risk factors. This typically involves blood tests and other investigations such as a heart tracing to check for atrial fibrillation and a scan of the carotid arteries in the neck.
Alongside managing any conditions that are found, usually it is advisable to start some new medication. This typically includes a high-dose statin to optimise cholesterol levels and keep artery disease stable, and a blood-thinning agent to reduce the risk of a second clot.
Stroke Recovery
This will look different for each person, depending on the severity of the stroke, and what part of the brain was involved. Generally, though, the recovery may involve support from Physiotherapists, Occupational Therapists (sometimes making modifications at home to help with mobility or other issues), PCPs, Speech And Language Therapists and Cognitive Behavioural Therapists. Stroke.org.uk has some fantastic resources(10) which go into more detail on what to expect when recovering from a stroke, including some helpful tips(11) for those looking after a stroke survivor.
If you think that you, or someone with you, may be having a stroke, please call 911 now.
For more information, including signs of stroke, please visit this blog(12) or view NHS advice here(13).
References
1. Andersen KK, Olsen TS, Dehlendorff C, Kammersgaard LP. Hemorrhagic and ischemic strokes compared: stroke severity, mortality, and risk factors. Stroke. 2009; 40:2068–2072. https://www.ahajournals.org/doi/10.1161/strokeaha.108.540112
2. https://www.nhs.uk/conditions/stroke/causes/
4. https://www.cdc.gov/high-blood-pressure/data-research/facts-stats/index.html
5. https://www.kinetikwellbeing.com/blood-pressure-tool/
6. https://www.coquitline.org/en-us/
8. https://www.nhs.uk/better-health/lose-weight/
9. VJ Howard, MN McDonnell. Physical Activity in Primary Stroke Prevention. Stroke. 2015;46:1735–1739 https://doi.org/10.1161/STROKEAHA.115.006317
10. https://www.stroke.org.uk/life-after-stroke
11. https://www.stroke.org.uk/finding-support/caring-for-a-stroke-survivor