Taking a daily low-dose (81mg) aspirin is one of the simplest preventive measures heart patients and those at a high risk for a cardiovascular event can follow. It’s also one of the most important. Yet people often stop this common prescription.
A new study suggests that stopping prescribed aspirin could be a serious mistake. The research, from Uppsala University in Sweden, involved more than 600,000 people who had been advised to take low-dose aspirin daily. Those who reported they had stopped taking the drug, about 15 percent of the patients, were 37 percent more likely to have a heart attack, stroke or other cardiovascular problem than those who stuck with the regimen.
Aspirin helps the heart by interfering with the blood’s ability to clot. When bleeding occurs, blood platelets clump at the site of the wound to seal it. However, when blood vessels are inflamed and narrowed by atherosclerosis, plaque deposits can burst, causing a clot to form and block the artery, which in turn can trigger a heart attack or stroke. Taking aspirin reduces the activity of platelets, keeping the blood flowing freely and decreasing the likelihood of a clot that would stop blood flow in the artery
Aspirin also helps by reducing inflammation, interrupting the processes that lead to atherosclerosis and clot formation. Current guidelines recommend that practitioners consider ordering low-dose aspirin for anyone who has had a heart attack to prevent a subsequent event as well as for those who are at an elevated risk for a first heart attack.
It’s not the first time that researchers have found a problem with stopping aspirin therapy. French researchers reached a similar conclusion in a 2005 study, in which researchers analyzed the medical records of more than 1000 patients hospitalized for heart problems, including heart attacks. Some 51 had stopped taking aspirin in the month prior to their hospitalization, and they accounted for 4 percent of all the coronary patients and 13 percent of those who had experienced a previous cardiovascular event.
Unfortunately, about 10 to 20 percent of the patients directed to take aspirin as a preventive measure discontinue their treatment in the first three years following the initial heart attack or stroke. The research suggests that patients would be wise to follow doctor’s orders.
Patients and physicians who have questions about the usefulness and effectiveness of aspirin therapy may want to consider the AspirinWorks® test, which helps determine if patients are responding well to aspirin therapy. It’s based on the fact that aspirin works by blocking the formation of an enzyme called thromboxane. Low thromboxane levels make platelets less likely to clump together and form clots.
Research shows that up to a quarter of people who take low-dose aspirin still have heart attacks and strokes. In some of them, aspirin may not adequately reduce the production of thromboxane, putting them at greater risk for experiencing a dangerous cardiovascular event. The AspirinWorks® test measures the level of thromboxane byproducts in patients’ urine. Those who are taking aspirin but still have high enzyme levels may not be deriving the needed benefit from the medication. Dose adjustments or alternative therapies may be indicated.
Low-dose Aspirin therapy may be critical to help protect people from heart attacks and strokes—but only if they take it consistently. It’s more important than ever to understand the benefits of this important preventive therapy and work with your practitioner to determine whether it’s right for you.