Transient Ischemic Attack Causes & Risks

Causes

A TIA results from a temporary blockage of the blood supply to the brain. The carotid artery in the front of the neck is a major supply of blood to the brain. A build-up of plaque and hardening of this artery can slow or stop blood flow.

Reasons for the blockage may include:

• A blood clot or a piece of plaque (called an embolus) from inside the wall of an artery breaks off and blocks blood flow to a portion of the brain.
• A blood clot dislodges from the heart and moves to the brain.
• Temporary low blood pressure in the brain may occur due to narrowed arteries in the neck.
• Blood and blood-clotting disorders such as:
  • Anemia (too few red blood cells)
  • Polycythemia (too many red blood cells)
  • Hyperviscosity (abnormal thickening of the blood)
• Vasculitis or blood vessel inflammation
• Endocarditis (infection of the lining of the heart)

Risk Factors

Factors that increase your chance for TIA and stroke are similar:

• Family history of stroke
• Age: 45 or older (highest risk 60-80 years of age); more common in men than women in younger age groups
• Atrial fibrillation —a common irregular heart rhythm
• Smoking
• High blood pressure
• Excessive alcohol use
• High cholesterol
• Obesity
• Certain medical conditions:
  • Diabetes
  • Heart disease
  • Sleep apnea
  • AIDS