The U.S. Preventive Services Task Force (USPSTF) has released a final recommendation statement on the use of aspirin for the primary prevention of cardiovascular disease (CVD) and colorectal cancer. Evidence shows that low-dose aspirin use is most beneficial for adults 50 to 59 years of age, according to the report. Adults 60 to 69 years of age should decide with their primary care clinicians whether aspirin use for primary prevention is right for them.
The new guidelines were published in the Annals of Internal Medicine.
The USPSTF used a calculator derived from the American College of Cardiology/American Heart Association (ACC/AHA) pooled cohort equations to predict 10-year risk for a first “hard” atherosclerotic CVD event (defined as a nonfatal myocardial infarction [MI], coronary heart disease [CHD] death, and a fatal or nonfatal stroke). Although concerns have been raised about the equations’ potential to over-predict risks, they are the only U.S.-based, externally validated equations that report risk as a combination of cerebrovascular and CHD events, the task force says.
Risk factors for gastrointestinal (GI) bleeding with aspirin use include higher dose and longer duration of use; a history of GI ulcers or upper GI pain; bleeding disorders; renal failure; severe liver disease; and thrombocytopenia. Other factors that increase risk for GI or intracranial bleeding with the use of low-dose aspirin include concurrent anticoagulation or nonsteroidal anti-inflammatory drug (NSAID) use; uncontrolled hypertension; male sex; and older age.
The USPSTF found adequate evidence that aspirin to treat cardiovascular events (nonfatal MI and stroke) in adults 50 to 69 years of age who are at increased CVD risk is of moderate benefit. The magnitude of benefit varies by age and 10-year CVD risk. The task force also found adequate evidence that aspirin use reduces the incidence of colorectal cancer in adults after five to 10 years of use. The USPSTF found inadequate evidence that aspirin use reduces the risk for CVD events in adults who are at increased CVD risk and are younger than 50 years of age or older than 69 years.
The task force found adequate evidence that aspirin use in adults increases the risk for GI bleeding and hemorrhagic stroke. The harms varied, but were small in adults 59 years of age or younger and small-to-moderate in adults aged 60 to 69 years. The USPSTF found inadequate evidence to determine the harms of aspirin use in adults 70 years of age or older.
The optimal dose of aspirin to prevent CVD events is not known. Primary prevention trials have demonstrated benefits with various regimens, including dosages of 75 and 100 mg per day, and 100 and 325 mg every other day. A dose of 75 mg per day appears to be as effective as higher doses, according to the recommendation statement. The risk for GI bleeding may increase with the dosage. The task force recommends 81 mg per day, which is the most commonly prescribed dosage in the United States.
Source: USPSTF; April 12, 2016.