Stroke Prevention

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Stroke Prevention
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Definitions of Stroke

• WHO Definition rapidly developing clinical
  signs of focal or global disturbances in cerebral
  function with symptoms lasting 24 hours or longer
  with no apparent cause other than vascular
  origin.
• World Health Organization Stroke-1989201407-31.

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Examples of Strokes
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Definition of Stroke-Simple Terms

• Brain Attack -caused by a blockage in an
  artery that carries blood to the brain. Without
  oxygen, that part of the brain is damaged and the
  function that part controls is affected.
• Loss of function- unable to speak or move an arm
  or leg.
• Loss may be temporary or permanent, partial or
  complete.

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Impact of Strokes

• 600-700,000 people in the US have a stroke each
  year.
• Incidence is rising and expected to double in 50
  years due to aging of the population.
• About 25 of those who have a stroke die within
  one year.

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Impact of Strokes-continued

• About 25 of those who experience a stroke
  recover fully.
• Survivors have varying degrees of disabilities.
• Direct Costs of Stroke totals 28.3 Billion
  Dollars per year.
• Total Costs of Stroke totals 43.3 Billion
  Dollars per year.

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How To Know If Youre Having a Stroke.

• If you have any of the following symptoms, call
  for emergency help immediately.
• Sudden weakness or numbness of the face, arm or
  leg on one side of the body.
• Sudden dimness or loss of vision, particularly
  in one eye.

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How To Know If Your Having a Stroke - continued.

• Loss of speech, trouble talking or
  understanding what others are saying.
• Sudden severe headache with no known cause.
• Unexplained dizziness, unstable walking or
  falling, especially along with any of the other
  symptoms.
• Loss of consciousness.

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TIAs or Mini-Strokes

• What is a TIA?
• A transient ischemic attack and represents a
  mini-stroke.
• TIA symptoms are the same as the warning signs
  for stroke, but they last only a few minutes or
  less than 24 hours.
• They are warning signs, as your risk for a future
  stroke is 7 per year on average.

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Risk Factors for Stroke

• Atherosclerosis
• Uncontrolled Diabetes
• High Blood Pressure
• High Cholesterol Level
• Smoking
• Previous Transient Ischemic Attack
• Heart Disease
• Carotid Artery Disease

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Modifiable Risk Factors

• These are generally medical conditions or
  behaviors that predispose an individual to have a
  stroke that could be changed or improved and thus
  lower the patients risk for stroke.
• Nonmodifiable Risk Factors include age, sex, race
  and heredity. These are generally things we
  cannot change.
• Risk of stroke increases exponentially with each
  decade of age.
• Men have more strokes then women.
• Blacks have higher incidence of strokes than
  whites.

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How Can I Avoid Having a Stroke?

• If your blood pressure is high, follow your
  doctors advice to control it. 24 hour control.
• Active control of blood pressure reduces the
  total stroke rate 42 and nonfatal strokes by
  44.
• 6mm decrease in diastolic40 reduction in
  incidence.
• Blood pressure reduction in the elderly47 ?.

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How can I Avoid Having a Stroke?

• Avoid foods that are high in fat and cholesterol,
  and eat less sodium (salt), to lower your
  cholesterol and blood pressure.
• Recent studies show increase risk of cerebral
  infarction with elevated cholesterol.
• Studies show reducing LDL-C of 23-42 decreases
  stroke risk 29 and overall mortality by 22.

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How can I Avoid Having a Stroke?

• If you have diabetes, keep your blood sugar level
  under control.
• Limit how much alcohol you drink.
• Lose weight if you are overweight.
• Regular aerobic exercise-lowers risk or
  atherosclerosis.

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How can I Avoid Having a Stroke?

• Quit smoking. If you dont smoke, dont start.
• Overall relative risk of stroke with smokers is
  1.5
• Relative risk varied among the 3 types of stroke.
• (1.92 for cerebral infarction, 1.01 for
  hemorrhagic stroke and 2.93 for subarachnoid
  hemorrhage.)
• Dose response between of cigarettes smoked and
  RR.
• Stroke rates drop after 3 years of cessation.

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Pharmacologic Prevention of Stroke.

• Antiplatelet Agents and Anticoagulants
• Antiplatelets work by stopping platelets from
  sticking to the wall of an injured vessel or
  other platelets.
• Anticoagulants work by blocking the formation and
  development of fibrin to forming a thrombus.

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Antiplatelet Therapy

• Aspirin-irreversibly limits platelet adhesion and
  aggregation.
• Associated with a 25 odds reduction overall in
  nonfatal stroke. It was 31 in high risk
  patients.
• Some uncertainty about appropriate dose. SALT
  (Swedish aspirin low-dose trial), and
  Antiplatelet Trialists Collaboration Group
  showed 75 mg as effective as large doses-500mg.
• Side Effects- GI upset, ulcers, bleeding, asthma,
  polyps. Bleeding time increases in 1-2 days and
  takes up to 7-10 days to return to normal.

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Antiplatelet Therapy

• Ticlide (ticlopidine)
• Works by different mechanism than aspirin but end
  result is the same-platelets dont work.
• Some studies (TASS) suggest it might be 21 more
  effective than aspirin by reducing strokes in
  high risk patients.
• Disadvantages Take twice a day. Affects bone
  marrow. Requires more lab monitoring.

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Antiplatelet Therapy

• Plavix (Clopidogrel)
• Works like Ticlid, and like aspirin prevents
  platelet aggregation.
• CAPRIE study, compared to aspirin, Plavix had a
  relative risk reduction of 8.7
• Disadvantage Cost.
• Advantages to Ticlid once a day, no lab, better
  tolerance.

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Antiplatelet Therapy

• Persantine (Dipyridamole)
• A platelet inhibitor, works synergistically with
  aspirin. Not effective against stroke alone.
• Studies show the relative risk of stroke was
  reduced by 18 with aspirin alone, 16 by
  Persantine alone, and by 37 by combination
  therapy.
• AGGRENOX is new at 200mg/25 mg and taken twice a
  day.

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Antiplatelet Therapy

• Antiplatelet agents are indicated to prevent
  ischemic stroke recurrences in patients who
• have had a previous stroke or TIA and have
  carotid stenosis.
• patients who have asymptomatic carotid stenosis
  more than 60, and
• in select patients with atrial fibrillation.

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Anticoagulant Therapy for Stroke

• Warfarin (Coumadin)
• Effective in preventing a second cardioembolic
  stroke in selected patients.
• Atrial fibrillation carries a 7-12 risk for
  stroke each year, but on warfarin this is 4 per
  year.
• Works by interfering with Vitamin K dependent
  clotting factors-requires lab monitoring.
  Increases risks for serious bleeding.

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Whom to Call for More Information?

• American Heart Association
• 800-aha-usa1 (800-242-8721)
• National Stroke Association
• 800-strokes (800-787-6537)