Alternate Names : Stroke, Brain Attack, CVA, Cerebrovascular Accident
A stroke is the death of brain tissue that occurs when the brain does not get
enough blood and oxygen. Hemorrhagic stroke is a serious condition that occurs
when blood seeps into the brain tissue from a damaged blood vessel.
What is going on in the body?
A hemorrhagic stroke occurs when blood vessels in the brain burst
and release blood into the area around the brain cells. The blood then damages
the brain cells. 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 hemorrhagic stroke may be caused by:
high blood pressure
abnormal bleeding from blood-thinning medications, such as warfarin or
hemophilia A or
hemophilia B, which are blood
prevent normal blood clotting
low numbers of platelets, a type of blood cell involved in blood
clotting. Low platelet counts are seen in a number of diseases and conditions,
including acute infections and a severe allergic reaction known as anaphylactic shock.
rupture of a cerebral
weakened blood vessel wall within the brain
sickle cell disease, an inherited condition that results in
abnormal red blood cells
a group of abnormal blood vessels within the brain known as an
arteriovenous malformation or AVM
eclampsia, a complication of
pregnancy that causes high blood pressure in the mother
The person's risk of hemorrhagic stroke 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
The nonmodifiable factors are ones that cannot be changed by the individual
increasing age. A person's risk of stroke doubles each year after age
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
ischemic attack (TIA). A TIA is a short, reversible form of stroke
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
high blood pressure
narrowing of one of the arteries in the neck
sickle cell anemia,
disorder that forms abnormal red blood cells
high cholesterol levels
blood, including total
LDL or "bad
cholesterol." Low levels
of HDL or "good
cholesterol" are also
cause for concern.
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:
a sedentary lifestyle with inadequate physical activity
high blood levels of homocysteine, a blood component sometimes associated
with a higher risk of stroke
blood disorders, such as blood that clots easily or deficiencies of various
The AHA currently states that the risk of stroke associated with HRT appears
low but needs further study.
birth control pills, or oral
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
pressure with thiazide diuretics, such as hydrochlorothiazide, had
significantly lower stroke risk than people on ACE inhibitors or calcium
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
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 product lines.
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.