Medicine Online
Any medical inquiries? Search MOL for answers:
Home > Medical Articles > Topics beginning with B > Brain Attack - Stroke from Atherosclerosis > Overview, Causes, & Risk Factors
Medical References
Diseases & Conditions
Women's Health
Mental Health
Men's Health
Medical Web Links
MOL Site Map
Medical Tips
Attention, chocolate lovers: You may not be able to help yourselves. Swiss and British scientists have linked the widespread love of chocolate to a chemical "signature" that may be programmed into our metabolic systems.
Read more health news

Brain Attack - Stroke from Atherosclerosis


Overview, Causes, & Risk Factors

A stroke is the death of brain tissue that occurs when the brain does not get enough blood and oxygen. A stroke from atherosclerosis occurs when the arteries supplying the brain are narrowed by plaque formation on the vessel walls.

What is going on in the body?

A stroke from atherosclerosis is classified as an ischemic stroke, which means it is caused when the blood supply to the brain is interrupted. Atherosclerosis is a thickening or hardening of the arteries. It can partially or totally block the flow of blood through an artery to the brain. The brain cells then die from lack of oxygen. The products released when cells die cause swelling in the brain. Since the skull doesn't allow much room for expansion, this swelling can damage the brain tissue even further.

What are the causes and risks of the condition?

A stroke from atherosclerosis is caused by the buildup of plaque on the inner walls of arteries supplying the brain. As plaque builds up in a person's arteries, the blood flow is interrupted and the person's risk of stroke increases. The person's risk of stroke from atherosclerosis is increased if other risk factors for stroke are also present.

The American Heart Association has recently issued guidelines for stroke prevention. The guidelines discuss risk factors for stroke in 3 categories: nonmodifiable, well-documented modifiable, and less well-documented or potentially modifiable.

The nonmodifiable factors are ones that cannot be changed by the individual and include:

  • increasing age. A person's risk of stroke doubles each year after age 55.
  • race. Strokes occur approximately twice as often in blacks and Hispanics as they do in whites.
  • gender. Men have a 50% higher chance of stroke than women do.
  • family history of stroke or transient ischemic attack (TIA). A TIA is a short, reversible form of stroke that may serve as an early warning sign of stroke.
  • Well-documented modifiable risk factors are those that can be changed by the individual in conjunction with his or her healthcare provider. These factors are linked to stroke by strong research findings, and there is documented proof that changing the risk factor lowers a person's risk of stroke. These factors include:

  • high blood pressure
  • smoking
  • diabetes
  • asymptomatic carotid stenosis, or narrowing of one of the arteries in the neck
  • sickle cell anemia, a blood disorder that forms abnormal red blood cells
  • high cholesterol levels in the blood, including total cholesterol and LDL or "bad cholesterol." Low levels of HDL or "good cholesterol" are also cause for concern.
  • atrial fibrillation, an abnormal heart rhythm
  • Less well-documented or potentially modifiable risk factors for stroke are those that have less proof of either a link to stroke or the impact of modifying the risk factor. These factors include:

  • obesity
  • sedentary lifestyle
  • alcohol abuse
  • high blood levels of homocysteine, a blood component sometimes associated with a higher risk of stroke
  • drug abuse
  • blood disorders, such as blood that clots easily or deficiencies of various blood components
  • hormone replacement therapy (HRT). The AHA currently states that the risk of stroke associated with HRT appears low but needs further study.
  • use of birth control pills, or oral contraceptives
  • inflammatory processes, such as a chronic infection with chlamydia
  • Several recent studies have identified factors that seem to increase or decrease the risk of stroke in particular groups of people. These studies, which warrant further investigation, include these findings:

  • People who were treated for high blood pressure with thiazide diuretics, such as hydrochlorothiazide, had a significantly lower stroke risk than people on ACE inhibitors or calcium channel blockers.
  • Women ages 39 to 50 who ate more fish and omega-3 polyunsaturated fatty acids had a reduced risk of stroke. This was particularly true in women who did not take aspirin regularly.
  • Women ages 15 to 44 who had 2 drinks of wine a day had a 40% to 60% lower risk of stroke than women who did not drink alcohol.
  • Phenylpropanolamine, a compound contained in appetite suppressants and cold remedies, significantly increased the risk of hemorrhagic stroke in women 18 to 49 years of age. The Food and Drug Administration (FDA) has since asked manufacturers to remove phenylpropanolamine from their products.
  • In one study, people who were treated in emergency departments for transient ischemic attacks (TIA) had a 25% chance of having a stroke or other serious health event within the next 90 days.

  • HomeSitemap Contact UsAdvertisingPress RoomGive Us Your FeedbackRead Our Terms & Conditions and Our DisclaimerPrivacy Statement