In the last couple of days, a wave of information came out that said healthy patients should no longer take aspirin to prevent a heart attack. Nevertheless, for some people, taking aspirin to prevent heart attack is critically important. Let’s try to clear up some confusion with definitions.
Primary prevention is aspirin use in healthy patients who don’t have artery disease. Aspirin use is no longer needed in most of these patients
Secondary prevention is aspirin use in patients with known atherosclerotic vascular disease or an equivalently high level of risk of heart attack and stroke. Patients with chronic kidney disease fall into this category. (estimated glomerular fitration rate 60 or less or microalbuminuria. Aspirin use remains critical in these patients. Please don’t stop it. That would be dangerous.
This is a great example of how scientific realities change. Heart attacks are clotting events. They occur when a cholesterol deposit breaks open, raw tissue hits the blood, and activates the clotting process. Then clot blocks the heart artery and heart muscle downstream dies. Aspirin prevents clot formation. All that is still true and when the first primary prevention trials with aspirin were done in the 1980s, they showed a dramatic benefit. Individuals without vascular disease at that time who took aspirin reduced their risk of a heart attack by 44%.
What changed? As with every medical decision, it is all about risk and benefit. In the 1980s more people smoked. High blood pressure, high glucose, and high cholesterol were more poorly controlled. ACE inhibitors like lisinopril, ARBs like losartan, statins, metformin, and spironolactone were not yet available or were much less commonly used. So our risk of heart attack and stroke has dropped enough that the risk of bleeding complications outweighs the small benefit of adding aspirin in patients who don’t have vascular disease or chronic kidney disease, especially for patients over 60.
Patients with higher risk still need aspirin. Patients with known atherosclerotic arterial disease anywhere still need aspirin therapy. That includes heart arteries, leg arteries, neck arteries etc. Patients who have had a heart attack, stroke, or angina still need aspirin. People with chronic kidney disease have such a high risk of heart attack and stroke that most don’t live to go on dialysis. They should be on aspirin.
The optimal medical therapy (OMT) trials that showed such dramatic results in high risk patients all included aspirin treatment as part of the protocol. The trials that proved optimal medical therapy alone is as good as optimal medical therapy plus a heart artery stent also included aspirin. OMT including aspirin in heart artery disease reduced mortality by up to 90% compared with usual care. Patients with type 2 diabetes and chronic kidney disease on OMT had one fourth as many heart attack and one fifth as many strokes compared with usual care. They lived 8 years longer on a protocol that included aspirin. Cardiovascular and related conditions are still the leading cause of death in the United States. OMT is the most effective treatment for artery disease in high-risk patients and aspirin is still part of that treatment. Don’t stop it.
Thank you for this clarifying article. The whole topic is confusing!
From our computational electrophysiological point of view, myocaridal dysfuction/damage is rooted in the supply abd demand imbalances, the vascular component is simply ONE of manay causes. For example. high altitude sickness due to low Oxygen supply can lead to myicardal damage, even death. Anoter example is the deep-diving-accidents, or the BENDS, can lead to the same myocardual damage. Thus the vascular centric arguements are over sold, which has created an entire indistry to sell coronary interventional devices and procedures, Statins drugs, antiocoagulants, etc. How effective these "remedies" really are, the data thius far have NOT support the exuberance. It is irrational and unscientific.
We need a systme of "telling the objective truth baed on, the first physical prinipals, understood via the honest learning from the impirical evidence" to regain trust, or we are ALL doomed.