Among the seemingly innocuous over-the-counter drugs many people reach for—sometimes daily—without thinking about possible adverse side effects, is aspirin.
Aspirin (acetylsalicylic acid) is commonly used to alleviate pain and inflammation. Daily low-dose aspirin has been advocated to reduce blood viscosity and prevent heart disease and strokes in high-risk individuals. However, it is frequently misused, with many people taking aspirin when unnecessary.
Besides its pain-relieving, fever-reducing, and anti-inflammatory properties, aspirin is also known for preventing blood clot formation. When plaques (deposits of cholesterol and other substances) rupture and the body attempts to limit the damage by forming clots, thrombosis occurs, which is a leading cause of heart attacks and strokes. Aspirin acts on platelets, and regular intake can reduce the blood’s ability to clot into thrombi.
A study published in the Annals of Internal Medicine in 2019 revealed that approximately 23.4 percent (about 29 million people) of adult Americans aged 40 or above reported daily aspirin use for cardiovascular disease prevention. Among them, 22.8 percent (about 6.6 million people) were not advised by their doctors to do so. Nearly half of individuals aged 70 or above without cardiovascular disease reported using aspirin.
Researchers noted that a significant portion of adults may be taking aspirin without a doctor’s recommendation and potentially without the doctor’s knowledge. It is essential for doctors to inquire about a patient’s current aspirin use and advise them to weigh the benefits and harms, especially for older adults and those with a history of peptic ulcers.
Under Harvard Medical School, Harvard Health Publishing an article highlighted that aspirin is frequently misused. Less than half of the individuals who could benefit from daily low-dose aspirin use it, and many take it when it is not indicated. If you do not have heart disease but have high blood pressure or other risk factors, it’s important not to automatically assume that taking daily aspirin is a beneficial choice. Brigham and Women’s Hospital cardiology expert Dr. Christopher Cannon stated, “Everyone assumes aspirin is harmless, but it’s not.”
A new study published in the Annals of Internal Medicine in July this year found that for healthy older adults aged 65 or above, daily low-dose aspirin use increases the risk of anemia by approximately 20 percent.
The researchers randomly assigned 19,114 participants aged 65 and above into two groups, one receiving 100 mg of low-dose aspirin daily and the other receiving a placebo. They monitored the participants’ hemoglobin and ferritin levels regularly over an average follow-up period of about 4.5 years. The results showed that low-dose aspirin use, unrelated to significant bleeding, decreased ferritin levels and increased anemia incidence among healthy older adults. Regular monitoring of their hemoglobin levels should be considered for older adults taking aspirin.
Zoe McQuilten, the lead author of the study and an associate professor at Monash University School of Public Health and Preventive Medicine, emphasized that while bleeding is a known side effect of aspirin, there has been limited research on the impact of long-term aspirin use on anemia in the older adults.
According to McQuilten, the study shed more light on the additional risk of anemia from aspirin use, especially for those with underlying conditions like kidney disease, for whom the impact might be more significant. She urged patients to follow their doctor’s advice when using aspirin regularly and only change their aspirin treatment after consulting their doctor. “Patients should not change their aspirin regimen without speaking to their doctor,” she said.
Anemia is a common condition in older adults, with a prevalence rate of 10 percent to 24 percent among this population, according to a review published in Blood in 2018. Hospitalized and institutionalized older adults are more susceptible to anemia, with 40 percent and 47 percent prevalence rates, respectively. Anemia prevalence increases with age, and in hospitalized and outpatient older adults, the prevalence among males aged 80 or above is close to 50 percent.
According to the National Institutes of Health (NIH), anemia in older adults is associated with functional decline, exacerbated fatigue, disability, depressive symptoms, and cognitive problems.
The U.S. Preventive Services Task Force published recommendations last year advising against using low-dose aspirin to prevent cardiovascular disease in adults aged 60 and above.
“If you’ve had a heart attack or stroke, there’s no doubt that taking low-dose aspirin is beneficial,” says Dr. Erin Michos, M.D., M.H.S., associate director of preventive cardiology for the Ciccarone Center for the Prevention of Heart Disease, in her health article “But if you don’t have heart disease, should you take it just in case? The answer for most individuals is probably not.”
Dr. Michos says, “But for the rest of my patients at lower or intermediate risk, it seems that the risks of aspirin outweigh the benefits.”
Dr. Michos also says that, particularly for older adult patients, she would think carefully about using it if they don’t have known heart disease. “Likely, other therapies such as the appropriate use of statin medications, more intensive blood pressure control, and smoking cessation are more important measures for prevention than taking aspirin.”
Dr. Michos suggests that the best way to assess risk levels is to discuss them with a health care provider. The doctor can help weigh the risks and benefits to determine whether low-dose aspirin treatment suits an individual.
