Published on February 12, 2018

Don’t quit your aspirin therapy abruptly

People who abruptly stop following their doctor’s advice to take a lose-dose aspirin daily are putting their health and life at risk.

A study recently published in the American Heart Association’s journal Circulation showed that suddenly stopping aspirin therapy increased the risk of suffering a cardiovascular event such as a heart attack or stroke by 37 percent. The study included more than 600,000 patients over a three-year period in Sweden.

This news might be surprising to most people, but not to cardiologists like Lawrence McAuliffe, MD, of Cape Cod Healthcare Cardiovascular Center in Hyannis.

“Cardiologists are keenly aware of the rebound effect of discontinuation of aspirin for the short term and the longer term renewed risk of cardiovascular events, if patients are off aspirin,” he said.

In a cardiology office, it is a rare patient who is not on aspirin therapy, either for primary prevention of future cardiac events based on risk factors, or secondary prevention in people who have already had a cardiovascular event.

“It’s an incredibly effective antithrombotic agent which becomes the cornerstone of all the therapies we prescribe,” Dr. McAuliffe said.

Some patients stop taking aspirin because they want to reduce the number of medications they take. Others simply forget. The other group of people who discontinue aspirin therapy are those who are having a procedure done by a non-cardiologist physician.

Stopping For A Procedure

Dr. McAuliffe regularly gets requests to discontinue aspirin therapy for two weeks before procedures like tooth extraction, plastic surgery, endoscopy, colonoscopy, bladder evaluations and other procedures where there is a risk of bleeding. In those cases, he negotiates with the other doctor to lessen the number of days off of the aspirin for the best outcome in both cases. The body replaces its platelets every seven days. Aspirin effects platelets, which are the backbone of blood clots.

If he can convince the other physician to lessen the number of days to six at the most, the patient will still have one day’s worth of aspirin protection. That offers at least some protection against cardiovascular events.

“We are generally able to negotiate a reasonable solution to that problem because the risk of bleeding really isn’t that high and we are always able to stop bleeding,” he said. “We are not always able to deal with the consequence of an acute cardiovascular event and what it does to a patient. No proceduralist doctor wants to have that complication.”

The exception would be neurologists or anesthesiologists who do spinal injections, he said. In those patients, the consequence of a bleeding issue around the spine can be devastating. Those patients are measured on a case-by-case basis to determine the benefit of the procedure versus the cost of stopping aspirin therapy.

81 Milligrams

Part of the reason bleeding isn’t really a huge worry is that patients on aspirin therapy only take 81 milligrams rather than the full dose of 325 milligrams. Over time, doctors discovered that 81 milligrams are quite sufficient to effectively inhibit the platelet activation that can cause a blood clot.

Dr. McAuliffe cannot recall a single patient who has had a problem with bleeding from another procedure because of low-dose aspirin. The lower dose is also much less likely to cause gastric problems, he said. Some people take coated aspirin as a prevention against gastrointestinal issues, but Dr. McAuliffe doesn’t recommend them.

“You don’t get a predictable level of 81 milligram protectiveness with coated aspirin, so I’ll often ask patients to get pediatric chewable aspirin, which is what I take,” he said. “You get a better absorption through the oral membranes anyway and if you are chewing it, you are not getting a pill that sits on the lining of your stomach and can cause an irritation or an ulcer.”

Dr. McAuliffe also tells patients that if they suspect they are having a heart attack, chew four 81 milligram aspirin immediately and call 911. Because the aspirin is absorbed through the oral membranes, it begins to work before it even hits the stomach.

“If a patient misses one dose or two doses, it’s not really going to make a difference, based upon the platelet physiology over seven days,” he said. “But if they completely discontinue it, then they are once again exposed to the lack of benefit that it does confer when taken as prescribed on a daily basis. That increases the risk of cardiovascular events.”