Monday, 11 June 2012

WHEN AND WHEN NOT TO ASPIRIN

Whether you think you can or whether you think you can't, you're right!

Experts agree that if you survive a heart attack or a clot caused (ischemic) stroke, you should take low dose aspirin. This holds true unless you have an aspirin allergy. In most cases, it also holds true if you have known blockages in the arteries that feed your heart or brain.

But what if you haven't been diagnosed with heart disease or had a stroke? Can an aspirin a day help you, too?

Aspirin reduces the risk of having a heart attack or ischemic stroke. It does this by making platelets in blood less likely to form clots. How much it can help depends on your risk of having a heart attack or stroke.

Aspirin helps a lot if you have already had a heart attack or stroke or if you have partial blockages in your arteries. But if neither of these applies to you, it actually helps very little.

If aspirin had no side effects, then it wouldn't matter whether your risk of heart attack or ischemic stroke was high or low. But we know that is not the case. Even low dose aspirin can cause serious problems. A low dose is generally defined as less than 325 milligrams of aspirin (one regular-strength tablet) daily.

Low dose aspirin can upset the stomach and contribute to the formation of ulcers. The most worrisome side effect is major bleeding. This mainly takes the form of bleeding from the stomach or intestines or bleeding into the brain (called a hemorrhagic stroke).

A new study strongly supports what we have known. Study results appear in the June 6 issue of the Journal of the American Medical Association. The researchers suggest that the prior studies have actually:

Underestimated the risk of major bleeding from low dose aspirin
Overestimated the ability of aspirin to prevent heart attacks and strokes
Another important finding in this study pertains to the benefits and risks of low dose aspirin in people with diabetes. Their baseline risk of major bleeding was found to be 36% higher than that of the general population, whether or not they used aspirin.

So aspirin did not cause people with diabetes to bleed any more than they would if they did not take aspirin. That's good. But wait. Aspirin also did not protect them from strokes and heart attacks as well as it did in the general population. The risks were lower, but so were the benefits.

You would think it's simple to decide about daily low dose aspirin. And for people who have been diagnosed with coronary artery or other blood vessel disease, it is simple. Take a baby aspirin (81 milligrams) daily unless you are allergic.

For everyone else, it gets a bit complicated.

If your heart and arteries are in good shape, consider your heart and blood vessel risk factors. Do you:

Smoke?
Have high blood pressure?
Have a high LDL (bad) cholesterol level?
Have family members with coronary artery disease that started before age 60?

If you answered no to all of the above, you would not take aspirin simply to prevent a heart attack or stroke. However, aspirin may have other benefits. For example, people who take aspirin appear to have a decreased risk of developing cancer, especially colon cancer.

What if you do have one or more of the heart risk factors? Your benefit score goes up with each risk factor you have. If the risk of major bleeding is the same for everyone, your benefit to risk ratio might favour low dose aspirin.

Until recently, daily aspirin was recommended for everyone with diabetes. Now your decision about taking an aspirin is similar to everyone else's. Aspirin is less effective at preventing heart attacks and strokes in people with diabetes. Scientists aren't sure why. Possible reasons include:

Decreased anti-clotting effects of aspirin
Increased platelet turnover in diabetics, therefore increasing the percentage of young, very sticky platelets that would be more aspirin resistant
High blood sugar levels pushing sugar into platelets, which changes how they are affected by aspirin


There will be no simple answer for many of us to the question of "if and when" we should take daily low-dose aspirin. But for people with heart or blood vessel disease or more than two heart risk factors, aspirin benefit will almost always outweigh risk.

The world cares very little about what a man or woman knows; it is what a man or woman is able to do that counts.