Aspirin
Within 48 Hours of Stroke Reduces Mortality, Disability
Taking
160 mg to 325 mg of aspirin within two days of ischemic stroke offers
a small but statistically significant" reduction in stroke death
and disability.
That's
according to a joint statement from the American Stroke Association, a
division of the American Heart Association, and the American Academy
of Neurology.
To
define the roles of antiplatelets and anticoagulants in acute ischemic
stroke, the Joint Stroke Guideline Development Committee searched the
literature for large, well-designed, randomized, prospective studies
on the topic. They found 310 worthy of full review, but only 10 met
all inclusion criteria and formed the basis of the group's
recommendations.
While
the benefits of aspirin within 48 hours of stroke onset are evident in
these studies, the authors say, there is insufficient data to make
recommendations on the use of other antiplatelet agents such as
clopidogrel and ticlopidine.
As
for the use of anticoagulants, there is no evidence that they reduce
death or disability when administered within two days of stroke onset,
the team reports. This result emphasizes the importance of reviewing
all the evidence to develop practice guidelines, committee chairman
Dr. Bruce Coull said in a statement. "Despite decades of use and
physiologic reasons for its use, there were surprisingly few
randomized trials that addressed the effects of heparin and other
anticoagulants within a few hours of onset of symptoms."
"There
is some evidence that a fixed dose of heparin given subcutaneously
might be helpful for preventing recurrent stroke, but the benefit is
balanced against the complication of increased hemorrhage, Dr. Coull
said. "With the net effect, there is no benefit to that
treatment."
Based
on available data, it is recommended that subcutaneous heparin be
considered to prevent deep-vein thrombosis (DVT) in some at-risk
patients. "Presumably by giving heparin to prevent clotting in
the veins, you decrease the likelihood that clots will travel to the
lungs and cause a pulmonary embolism," the researcher from the
University of Arizona in Tucson, said.
Dr.
Coull hopes the statement will have a three-fold effect on clinical
practice. First, in the absence of contraindications, all acute stroke
patients will receive aspirin; second, that acute stroke patients will
have the issue of DVT addressed; and third, that heparin will be used
sparingly in this setting.
The
new guidelines are published in the July issues of Stroke: Journal of
the American Heart Association, and Neurology, the scientific journal
of the American Academy of Neurology.
Neurology
2002;59:13-22.
