Stroke Prevention Part 1

Platelets are small blood particles that can clump together and block the flow of blood into areas of the brain. When the blockages last for only a few minutes, the effect can be a temporary impairment, such as difficulty speaking, numbness or tingling or weakness that lasts for up to a few hours. These events are called Transient Ischemic Attacks (TIAs). When the blockage lasts longer, the loss of function may not recover and this is called a stroke.

One of the important ways to prevent stroke is to prevent platelet clumping. Typically, treatments to prevent platelet clumping are started after a TIA or stroke has already occurred.

This post will cover the options for preventing platelet clumping.

Aspirin

Aspirin is the mainstay of treatment. It is inexpensive and usually well tolerated. It is often effective, typically at a dose of 81 mg per day. Higher doses (325 mg) are sometimes used at the onset of a TIA or stroke, usually just for the first dose.

Failure of aspirin to prevent ischemic events occurs in about 1/3 of all patients taking aspirin. The reasons for failure were mostly related to:

• Failure to TAKE the aspirin (just having the bottle in the home or just thinking about taking it doesn't prevent strokes!)
• A low HDL cholesterol as compared to total cholesterol (chol/HDL >2.99)
• A high resting heart rate (>69 bpm)
• Elevated triglycerides
• Patients with diabetes may have less of an antiplatelet response to aspirin, and at least one study suggests that aspirin is ineffective as stroke prevention in diabetics

So, to make sure aspirin is working for you, take it every day, do aerobic exercise daily (check with your doctor before doing this) or perhaps take a beta blocker, and take a statin to lower your cholesterol (and exercise, because exercise raises HDL).

Aspirin + Dipyridamole ER

The combination of extended release dipyridamole and aspirin is somewhat more effective than aspirin alone. This is taken twice daily. Most patients develop temporary headache during the first few days of taking this medication, which goes away within one week. Only about 80% of people who start this medication stay on it long term. The brand name is Aggrenox.

Plavix

Plavix is taken once daily. Sometimes, it may be "loaded" which means that the patient may be asked to take several pills at one time to get the blood level up quickly (usually 300 mg or 4 Plavix). The evidence so far suggests that loading Plavix is safe. When compared to Aggrenox, Plavix is equally effective in preventing strokes in the first 30 days after an event (TIA or stroke). Side effects are slightly less problematic with Plavix, at least in the short term. About 88% of people who started this medication stay on it long term. Some people are resistant to Plavix because their body is unable to metabolize Plavix into its active metabolite. These people have a genetic abnormality that leads to an abnormal hepatic enzyme (CYP2C19). This can be checked for with a blood test, and if positive, may indicate the need to use something other than Plavix or a higher daily dose. Plavix also is partially inactivated by proton pump inhibitors. If a medication to control GI acidity is needed, Zantac, Pepcid or Axid are recommended.

Plavix + Aspirin

May be best treatment for acute TIA treatment to prevent stroke, especially in non-diabetics. This combination is often used when a person presents with a TIA or small stroke. Typically, the patient is given 325 mg of Aspirin and 300 mg of Plavix in the emergency room and then placed on Aspirin 81 mg and Plavix 75 mg daily for 30 days. Beyond 30 days, there is no good evidence that this combination is superior to Plavix alone or Aggrenox.

Cilostazol

Improves cerebral blood flow and is equivalent to aspirin in stroke prevention in one small study. Cilostazol is perhaps superior to other treatments in those with lacunar strokes due to hypertension or diabetes, but this is still contraversial.

Ticlopidine

Equally effective to Plavix but less well tolerated and perhaps more adverse events. It requires lab tests (CBC, Platelet Count) to monitor its safety.

Folate (2.5 mg) + B6 (50 mg) + B12 (1 mg)

Combination prevented second stroke in 3 out of 1000 patients treated. The benefit is slight, but if a person cannot tolerate any other treatment, this is perhaps better than nothing.

Omega 3 Fish Oil

No hard data, but is being used to combat strokes.