Last Updated: February 2, 2015
Known as a "warning stroke," a transient ischemic attack (TIA)
often comes and goes so quickly that the affected person may not
even be aware they've had one. Yet medical experts stress it is
vitally important for a person who has suffered a TIA to get
immediate medical attention, because a TIA is a sign that the
person is more likely to subsequently suffer a full stroke.
More than one-third of the people who have had one or more
transient ischemic attacks will have a stroke in the future,
according to data published by the American Heart Association. A
significant percentage of these people may experience a stroke in
the short term, making the need for medical treatment even more
"The data suggests that about 10% of people who have had a TIA
will have a stroke within three months. Five percent will have the
stroke within 48 hours," says Dr. Kyra Becker, co-director of the
University of Washington Stroke Center and associate professor of
neurology and neurological surgery at the University of Washington
School of Medicine. Those percentage figures alone should motivate
a quick trip to the doctor or emergency room, Becker says.
Older persons, especially, should carefully monitor a transient
ischemic attack, according to medical experts, as they are more
likely to suffer strokes. "A TIA in a younger person tends to be a
fluke," says Dr. Richard Burgess, a clinical fellow at the National
Institute of Neurological Disorders and Stroke. "It is more often
the harbinger of a further event in an older person."
Unfortunately, many people who suffer a TIA misread the symptoms
and shrug off the attack as nothing more than a momentary
"This is the big problem we run into with people who have TIAs,"
says Burgess. "They don't recognize it as something that is very
The symptoms for a transient ischemic attack are similar to
those of a stroke, but are much shorter in duration, as the average
TIA lasts less than five minutes. Most symptoms disappear within an
hour, but can, on occasion, last up to 24 hours.
According to information published by the Mayo Clinic, the most
common symptoms of a TIA are similar to those of a stroke and
- Sudden weakness, numbness or paralysis in your face, arm or
leg, typically on one side of your body
- Slurred or garbled speech or difficulty understanding
- Sudden blindness in one or both eyes or double vision
- Dizziness, loss of balance or loss of coordination
However, because the event is so short in duration, the symptoms
may not always distress a person enough to seek medical help. While
a person who temporarily loses sight is likely to follow up with a
doctor, people are less likely to report a momentary paralysis in a
part of the body, Burgess explains. Although momentary paralysis is
actually a very common kind of TIA, many people assume they merely
slept, or were sitting, in an odd position and so lost circulation.
Making this assumption and ignoring the symptoms "is absolutely the
wrong thing to do," says Becker.
Of course, not every episode of a foot "falling asleep"
indicates the presence of a minor stroke-the transient ischemic
attack typically involves the entire side of a person's body. "A
TIA is a very specific loss of power on the side of your body,"
Becker says. "It's not just in an arm or hand."
Key to recognizing a TIA is being aware of the situation in
which the event was produced, and of the nature of the symptoms
experienced. For example, if the event occurs in the midst of an
activity, or doesn't go away within five minutes, that is a clear
Understanding TIA and Strokes
A transient ischemic attack, like the most common kind of
stroke, is caused by a temporary decrease in blood supply to the
brain. This occurs when an artery that supplies oxygen and
nutrients to the brain is blocked by a buildup of cholesterol-containing
fatty deposits called plaques (atherosclerosis).
These blood clots can form either in the heart or other blood
vessels; when they travel to the brain, they become lodged and
prevent blood from flowing into the brain. Blood clots are formed
from a failure in the body's mechanisms for breaking down the
clots; medical experts note that it is difficult to explain why
some clots are broken up and others not. It is difficult to
predict, and not necessarily related to the actual physical
condition of the patient. Eighty-five percent of strokes are caused
by such a blood clot.
Common repercussions of a stroke include paralysis or problems
controlling motion, sensory disturbances including pain, problems
using or understanding language, problems with thinking and memory,
and emotional disturbances. In the most severe case, a stroke can
lead to death.
A major difference between a TIA and a stroke, however, is that
a TIA is unlikely to produce lasting damage. This is because the
TIA is such a quick event that the brain is able to recover from
the loss of oxygen and nutrients.
The risk factors for transient ischemic attack and stroke are
identical. Some are purely hereditary. This includes family
history, race, and gender. A combination of genetic differences and
access to health care makes minorities more likely to suffer a TIA
or stroke than whites. Additionally, men are more likely than women
to have a fatal stroke, according to Becker.
Another non-variable risk factor is age. "The risk of a stroke
doubles with each successive decade after 55," Becker says. This is
the result of changes in the body. For example, an older person is
more likely to have high
blood pressure. It's a cumulative process, says Burgess: as a
person ages, their arteries harden and narrow, and at the same
time, cell deposits are more likely to stick to the artery walls.
"Older people are less able to heal in general. Just the force of
having blood under higher pressure than lower, produces more
scraping against blood tissue walls and things stick to them
Prevention and Treatment
Some risk factors can be controlled. These include high blood
pressure, smoking, heart disease, and diabetes. While patients can
simply quit smoking to reduce chances of getting a stroke, the
other risk factors need to be carefully managed and treated.
Strokes are the third leading killer of adults in America. Each
year, more than 700,000 Americans have a stroke, with more than
160,000 dying of stroke-related causes. However, recent studies
show that progress is being made in prevention, according to
information published by the National Institute of Neurological
Disorders and Stroke (NINDS).
In recent years, a better understanding of the causes of strokes
have helped Americans make lifestyle changes that have cut the
stroke-related death rate in half, according to the NINDS
publication. For example, carefully monitoring blood pressure and
diabetes through diet and other treatment options has been shown to
play an important role in reducing the risk of a transient ischemic
attack or stroke. "Being aggressive about treating blood pressure
and glucose helps prevent future events-data very clearly says that
blood pressure is significant risk," Becker says.
Key among stroke
prevention efforts is not only identifying a TIA, but following
through with preventive treatment. Depending on the causes of the
TIA, doctors may recommend a medication regimen, or surgery.
Antiplateletdrugs make platelets less likely to stick together
and form blood clots. Aspirin is a popular anti-platelet drug as it
is the least expensive and also has the least side-effects. More
aggressive alternatives to aspirin are the anti-platelet drugs
Plavix®(clopidogrel bisulfate) and Aggrenox®,
a combination of low-dose aspirin and the anti-platelet drug
Anticoagulantsare drugs that are given to prevent blood clots
from forming or existing blood clots from getting larger. Common
names for anticoagulants are warfarin and heparin. Patients on
anticoagulants should be carefully supervised by their physicians
with regular blood tests, and should tell their doctors if they are
taking or are thinking of taking anything else like vitamins, cold
medicine, or antibiotics, as these can make the drugs stronger or
While these drugs help prevent a future, more serious formation
of blood clots that could potentially trigger a full stroke, they
do have side-effects: patients are more likely to bruise easily and
experience excessive bleeding.
Besides the anti-platelets and anticoagulants, clinical data
suggests that putting at-risk people on high-dose
cholesterol-lowering medications can prevent a future stroke,
according to Becker.
Doctors may also recommend surgery for patients who have
suffered a transient ischemic attack. For example, if the TIA was
produced by a carotid artery, the doctor may recommend an
endarterectomy, a surgical procedure that treats a narrowing in the
artery by clearing the affected artery of fatty deposits before
another TIA or stroke can occur.
In some cases, a procedure called carotid angioplasty, or
stenting, is an option. This procedure involves using a
balloon-like device to open a clogged artery and placing a small
wire tube (stent) into the artery to keep it open. According to
Becker, this procedure is still being studied and is considered