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Causes of a Stroke

A stroke is caused by an interruption in the flow of blood to the brain. The two main reasons that this blood flow stops are:¹

• A narrowing, hardening, or weakening of blood vessels
• A thickening or clot of the blood

Narrowing of the arteries is usually the result of fatty deposits that have built up on the artery walls. The narrowed diameter of blood vessels mean that the blood flow to major organs such as the brain is constricted. If one of these fatty deposits (also called plaques) breaks off, the artery wall, a blood clot forms where the plaque has detached. If it is big enough, this clot blocks the artery causing the blood supply to the brain be cut off.⁵

People who have pre-existing medical conditions that affect blood circulation, such as high blood pressure (hypertension), diabetes, carotid artery disease, or heart disease, have an increased risk of having a stroke.^{1, 2} In addition, if you’ve had a stroke or mini-stroke before you’re more likely to experience another.²

Besides pre-existing medical conditions, lifestyle and genetic factors play a role in whether you’re at risk of a stroke or not.

1. Fixed risk factors

These are genetic risk factors that cannot be changed, and include:²

• Sex: Men are more likely to have strokes than women
• Age: Strokes are more common after the age of sixty-five, with the risk continuing to rise with further aging
• Family history: If you have a close relative who has had a stroke your risk of having one yourself is increased
• Ethnic background: People from certain ethnic backgrounds including Asian, African, and African-Caribbean communities are at a greater risk of a stroke

2. Variable risk factors:

These are lifestyle factors that can be changed, and include:^{2, 3, 5}

• Smoking: Chemicals in tobacco can damage your arteries; damaging blood vessel walls and also causing blood pressure to increase
• Obesity: Carrying extra weight can place strain on your heart, arteries, and circulation
• A poor diet: You should eat a balanced diet low in salt and saturated fats
• Being inactive: If able, you should engage in regular physical exercise to increase your heart capacity and stimulate circulation
• Excessive consumption of alcohol: You should aim to drink in moderation and should avoid binge drinking

In some cases, strokes happen to people without any obvious risk factors being present.¹

Disease Information

• Angina
• Depression
• Diabetes (Type 2)
• Heart Attacks
• Heart Failure
• High Blood Pressure
• Osteoporosis (Postmenopausal)
• Stroke