Diseases & Conditions

 

Stroke

Diseases & Conditions

 

What is stroke?

A stroke occurs when blood flow to an area of the brain is interrupted or severely reduced. When this happens, part of the brain cannot get enough oxygen and brain cells begin to die. A stroke is a serious life-threatening condition and immediate care is required to minimize brain damage and life-time complications.

In 2010, the prevalence of stroke was 33 million people worldwide, with 16.9 million people having a first stroke. Stroke was the second-leading global cause of death after heart disease, accounting for 11.13% of total deaths worldwide.1

In Saudi Arabia, the incidence and prevalence of strokes are lower than those recorded in Western countries, which could be due to the predominance of the younger age groups in the kingdom.2

What causes stroke?

There are two types of strokes:3

  • Ischemic stroke: It occurs when the blood supply is stopped due to a blood clot (this accounts for 87% of all cases).3 The most common ischemic strokes include:
    • Thrombotic stroke: It occurs when a blood clot (thrombus) forms inside one of the brain's arteries.
    • Embolic stroke: It occurs when a blood clot forms elsewhere in the body (embolus) and travels to the brain.

 

  • Hemorrhagic stroke: It occurs when a diseased blood vessel in the brain bursts. Types of hemorrhagic stroke include:
    • Intracerebral hemorrhage: It occurs when a weakened blood vessel within the brain ruptures, allowing blood to leak inside the brain.
    • Subarachnoid hemorrhage: It occurs within the subarachnoid space, which is the area between the brain and the tissues that cover it.
    • Transient ischemic attack. Transient ischemic attacks are episodes in which a person has signs or symptoms of a stroke that only last for a short time.

 

 What are the risk factors for stroke?

The major risk factors for stroke include:4

  • Lifestyle risk factors:
    • Being overweight or obese
    • Lack of physical activity
    • Use of illegal drugs including cocaine and methamphetamines

 

  • Medical risk factors
    • Hypertension
    • Smoking and secondhand smoke
    • Unhealthy cholesterol level
    • Type 2 diabetes mellitus
    • Sleep apnea
    • Cardiovascular diseases

 

  • Other factors associated with a higher risk of stroke include:
    • Family History: Stroke is thought to run in families.
    • Older age: People over 55 years old are at increased risk of developing strokes.
    • Race and ethnicity: Blacks are at higher risk than whites
    • Gender: Men have a higher risk of stroke than women.

 

What are the symptoms of stroke?

Signs and symptoms of a stroke may include:5

  • Sudden weakness
  • Paralysis or numbness of the face, arms, or legs, especially on one side of the body
  • Confusion
  • Trouble with speaking and understanding
  • Trouble with seeing in one eye or both
  • Problems breathing
  • Dizziness, trouble walking, loss of balance or coordination, and unexplained falls
  • Loss of consciousness
  • Sudden and severe headache

  

How is a stroke diagnosed?

A doctor may use several tests to determine the risk of stroke:

  • Physical examination: The doctor will listen to the heart and lungs and look for signs and symptoms of stroke.
  • Blood tests: Different blood tests are required to measure blood chemicals, sugar level and how fast blood clots.
  • Computerized tomography (CT) scan: This test uses X-ray to create a detailed image of the brain to see if there is a hemorrhage, tumor, or stroke.
  • Magnetic resonance imaging (MRI): This test can show which parts of the brain are damaged.
  • Carotid ultrasound: This test creates pictures of the insides of carotid arteries which supply oxygen-rich blood to the brain to see whether plaque has narrowed the arteries.
  • Cerebral angiogram: This test helps to find blockages in the blood vessels of head and neck.
  • Echocardiogram: This test shows the size and shape of the heart and a source of clots that may have travelled to the brain.

 

How is a stroke treated?

Treatment depends on whether a patient is having an ischemic stroke or a hemorrhagic stroke:

  • Treatment for ischemic strokes:
    • Aspirin: Antiplatelet agents such as aspirin interfere with the blood's ability to clot and can play an important role in preventing stroke
    • Intravenous injection of tissue plasminogen activator (TPA): TPA is a protein involved in the breakdown of blood clots.
    • Medications delivered directly to the brain: Doctors may deliver TPA directly into the area where the stroke is occurring.
    • Mechanical clot removal: This procedure consists of a device inserted into the brain to remove blood clots.
    • Carotid endarterectomy: This procedure consists of opening blocked carotid arteries.
    • Angioplasty and stents: This procedure consists of opening blocked carotid arteries and a stent is inserted to support the opened artery.

  

  • Treatment for hemorrhagic strokes:
    • Medications: Antiplatelet agents such as aspirin interfere with the blood's ability to clot and can play an important role in preventing stroke
    • Surgical blood vessel repair: This surgery consists of repairing blood vessel abnormalities associated with hemorrhagic strokes.

 

 References

  1. Mozaffarian, Dariush, et al. "Heart disease and stroke statistics-2015 update: a report from the american heart association." Circulation 131.4 (2015): e29.
  2. Robert, Asirvatham Alwin, and Marwan Mohamed Zamzami. "Stroke in Saudi Arabia: a review of the recent literature." The Pan African medical journal 17 (2014).
  3. Miller, Elaine L., et al. "Comprehensive overview of nursing and interdisciplinary rehabilitation care of the stroke patient a scientific statement from the American Heart Association." Stroke 41.10 (2010): 2402-2448.
  4. Stroke (Symptoms and causes) http://www.mayoclinic.org/diseases-conditions/stroke/symptoms-causes/dxc-20117265 (Accessed January 13, 2016)
  5. What Are the Signs and Symptoms of a Stroke? (- NHLBI, NIH) https://www.nhlbi.nih.gov/health/health-topics/topics/stroke/signs (Accessed January 13, 2016)
  6. Stroke Diagnosis (Stroke Diagnosis) http://www.strokeassociation.org/STROKEORG/AboutStroke/Diagnosis/Stroke-Diagnosis_UCM_310890_Article.jsp#.VpcwvMZ97IU (Accessed January 14, 2016)
  7. Stroke (Treatment) http://www.mayoclinic.org/diseases-conditions/stroke/diagnosis-treatment/treatment/txc-20117296 (Accessed January 14, 2016)