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Question:
Should I know what my blood viscosity is before starting aspirin?
I am a 67-year-old male, in good health, who was recently diagnosed with a small piece of plaque in my eye. While this poses no threat to my vision, both the neuro-ophthalmologist and my cardiologist think I should go on a low dose aspirin regiment asap. My problem is, given all of the well known side effects from this therapy, shouldn't I know something about the current viscosity of my blood and what level I should be at to avoid a cardiological event? Is viscosity testing a starting point and if so are there target levels to aim for? Also are other organic solutions just as effective, i.e. fish oil, pycnogenol, vitamin E? I appreciate any advice you can provide me. Thank you.
submitted by Ernie from New York on 10/20/2014
Answer:
by Texas Heart Institute cardiologist, Michael J. Mihalick, MD
Dear Ernie:
The viscosity (rheology) of blood is very complex because it is a mixture of water, water soluble minerals and compounds, water insoluble fats carried by 'detergent' proteins, and living cells. It is not analogous to compounds like motor oil. The viscosity of blood is very nonlinear and only becomes important in rare conditions resulting from the overproduction of blood cells or proteins.
Strokes and heart attacks are caused by occlusion of arteries due to blood clots which form at the site of obstruction (thrombotic) or form at an upstream site and lodge at the site of obstruction (embolic).
The clotting process is triggered by exposure of platelets to a defect in the lining of the artery caused by a cut or arterial disease (arteriosclerosis). Aspirin decreases the sensitivity of platelets to this trigger and has been shown to decrease the risk of stroke and heart attack.
80-100mg of aspirin are effective in most people. Since 20-30% don't absorb aspirin well, and because coated aspirin is not well absorbed, 150 mg or higher are often recommended. If aspirin has ever upset your stomach, you are an absorber of that dose.
The risk of bleeding from aspirin is greatly outweighed by its benefit.
The other compounds you mentioned do not have the proven benefit of aspirin. Initially, vitamin E had circumstantial evidence of benefit. This has clearly been disproven by multiple large scale trials here and in Europe.
I hope this answers your question.
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Updated October 2014
