Connection between Blood Clots and Strokes: Unveiling the Relationship

Connection Between Blood Clots and Strokes: Uncovering the Relationship

Ischemic and hemorrhagic strokes are two types of brain attacks, each with distinct causes and risk factors.

Ischemic Stroke

An ischemic stroke occurs due to an interruption of blood flow to the brain, usually caused by thrombosis, embolism, or atherosclerosis. Thrombosis involves the formation of a blood clot in an artery of the brain, while embolism refers to a clot formed elsewhere, often the heart, that travels to the brain arteries. Atherosclerosis, the build-up of fatty plaques in arteries, narrows or blocks blood flow, leading to ischemic stroke.

Key risk factors for ischemic stroke include high blood pressure (the most important modifiable risk factor), high cholesterol, diabetes mellitus, tobacco smoking, atrial fibrillation, and heart disease. Non-modifiable factors such as advanced age, male gender, family history, and a previous transient ischemic attack (TIA) or stroke also increase the risk. Neuroinflammation, indicated by a high neutrophil-to-lymphocyte ratio, is linked to worse ischemic stroke outcomes.

Hemorrhagic Stroke

Hemorrhagic stroke results from bleeding within the brain tissue. Common causes include intracerebral haemorrhage, caused by chronic hypertension leading to rupture of small arteries or arterioles, and vascular malformations such as cavernous angiomas or arteriovenous malformations. Cerebral amyloid angiopathy, the deposition of amyloid in vessel walls, increases fragility and can lead to bleeding. Secondary hemorrhage into an ischemic infarct, trauma, bleeding disorders, and illicit drug use can also cause hemorrhagic strokes.

Risk factors for hemorrhagic stroke overlap with ischemic stroke but also include the use of blood thinners or bleeding disorders, vascular abnormalities, illicit drug use causing arterial spasm or rupture, advanced age, and male gender.

Prevention and Lifestyle Changes

Maintaining a moderate weight, getting regular exercise, eating a diet high in fiber and low in saturated fats, trans fats, and cholesterol, and avoiding or limiting alcohol may help prevent both types of stroke. Discussing health conditions with a doctor and taking steps to control diabetes, blood pressure, cholesterol, and heart disease are also crucial.

Importance of Awareness

Stroke is the leading cause of death worldwide and affects almost 800,000 people in the United States annually. People at high risk of developing blood clots may need blood thinning medication, such as antiplatelets or anticoagulants. Recognising the signs of a TIA (mini-stroke) and learning how to avoid a stroke after a TIA may be beneficial. The Centers for Disease Control and Prevention (CDC) notes that Black people are more likely to die from a stroke than white people, possibly due to inequities in healthcare.

Learning about treatment and home management for blood clots, moving around every few hours during long periods of sitting, and moving around as soon as possible after surgery or illness may help prevent blood clots. Conditions such as sickle cell disease and atrial fibrillation increase a person's risk of stroke, highlighting the importance of regular check-ups and discussions with healthcare providers.

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[2] National Institute of Neurological Disorders and Stroke. (2021). Brain Attack Coalition Fact Sheet. [online] Available at: https://www.ninds.nih.gov/sites/default/files/media-files/Brain-Attack-Coalition-Fact-Sheet.pdf [Accessed 20 Mar. 2023].

[3] American Academy of Neurology. (2018). Association of Neutrophil-to-Lymphocyte Ratio With 3-Month Functional Outcome in Acute Ischemic Stroke. [online] Available at: https://www.aan.com/press/association-of-neutrophil-to-lymphocyte-ratio-with-3-month-functional-outcome-in-acute-ischemic-stroke/ [Accessed 20 Mar. 2023].

[4] American Heart Association. (2020). High Blood Pressure Control A Major Step in Stroke Prevention. [online] Available at: https://www.heart.org/en/news/2020/05/26/high-blood-pressure-control-a-major-step-in-stroke-prevention [Accessed 20 Mar. 2023].

[5] Centers for Disease Control and Prevention. (2021). Stroke Facts. [online] Available at: https://www.cdc.gov/stroke/facts.htm [Accessed 20 Mar. 2023].