Aspirin is one of the most widely used medications in the U.S., both as a prescription drug and as an over-the-counter drug. According to the Drug Facts label on medication products, aspirin can be used to relieve minor complaints, such as headaches, pain, swelling and fever.
Aspirin is also prescribed by physicians for other purposes besides pain relief. In fact, low doses of aspirin is believed to help people who are at-risk of, or who already have, heart disease reduce their risk of heart attack and clot-related stroke.
But in 2018, three clinical trials revealed that taking aspirin for exactly those purposes actually does more harm than good. The results showed that taking the medication daily offers very few benefits and even elevates the risk of bleeding, especially in people without heart disease.
An earlier study also reported that the majority of those who use aspirin are older adults who neither have heart disease nor were advised by their physicians to take the drug. But what some of these people have is peptic ulcer disease, and their use of aspirin only increases the risk of their ulcers bleeding.
These findings led the American Heart Association (AHA) and the American College of Cardiology (ACC) to change their guidelines about the use of aspirin in clinical practice. They also highlighted the need for healthcare practitioners to ask their patients about their aspirin use.
The cons of using aspirin to prevent cardiovascular disease
Heart attack and stroke usually occur due to blood supply to the heart or the brain being cut off. Atherosclerosis, a disease characterized by the buildup of plaque in the arteries, is the most common cause of this. In atherosclerosis, a combination of cholesterol and immune cells form plaque that stiffens or narrows the blood vessels, reducing blood flow to major organs. The damage to the heart caused by this limited supply of oxygen and nutrients leads to a heart attack.
However, there are times when arterial plaques rupture, causing blood clots to form. These clots further clog the blood vessels and stop blood flow to other parts of the body. Blood clots that affect the blood supply to the heart also causes a heart attack while blood clots that block the flow of blood to the brain causes a stroke. Aspirin is often prescribed to prevent these cardiac-related events because it has the ability to thin the blood, making it less likely to form blood clots.
In a recent study published in Annals of Internal Medicine, researchers at Harvard Medical School and the Beth Israel Deaconess Medical Center in Boston reported that about a quarter of American adults aged 40 and above are using aspirin every day. These people do not suffer from cardiovascular disease but are taking the medication as a means of disease prevention. (Related: Low-dose aspirin found to increase risk of intracranial hemorrhage.)
Of these 29 million adults, 6.6 million use aspirin without the knowledge or consent of their physicians. Meanwhile, nearly half of American adults aged 70 years or older also take aspirin daily despite having no history of cardiovascular disease or stroke. According to Dr. Christina Wee, senior author of the study, she and her team found this surprising as it is a well-established fact that older people have a higher risk of bleeding from aspirin.
However, it seems that for older Americans, preventing heart-related conditions is worth the risk. Peptic ulcer disease refers to a condition in which ulcers or sores appear in the lining of the small intestine. Aspirin is not prescribed to people with this disease as the medication is highly likely to cause their ulcers to bleed. If left untreated, ulcer bleeding can lead to anemia or severe blood loss, which will require hospitalization or a blood transfusion to treat.
“Our findings show a tremendous need for healthcare practitioners to ask their patients about ongoing aspirin use, and to advise them about the importance of balancing the benefits and harms, especially among older adults and those with prior peptic ulcer disease,” said Dr. Colin O’Brien, the lead author of the study.
As of 2019, the new AHA and ACC guidelines recommend against the use of aspirin among adults aged 70 and above who do not have a history of heart disease or stroke.