Ask The Doctors: November 2018
Q: I have been taking a statin for 12 years and clopidogrel with aspirin since my heart attack three years ago. Is it okay to take these medications for such a long time?
A: Both statins and clot-inhibiting medications like aspirin or clopidogrel have proven benefits after a heart attack (myocardial infarction, or MI). As with any medication that you take for years, the long-term benefits must be weighed against the risks. Statins inhibit an enzyme important in the synthesis of cholesterol and lower LDL cholesterol by 50 to 60 percent. Statins offer additional protective effects beyond LDL lowering, but these effects cease if the statin is stopped.
Due to strong evidence that statins help prevent recurrent MI and death over the long term, it is recommended that patients who have suffered a heart attack take a statin indefinitely, if the medication is tolerated. There is also agreement that low-dose aspirin be continued indefinitely after MI, unless serious side effects are experienced.
Whether to continue taking clopidogrel with aspirin over the long term is a different issue. Aspirin alone can increase the risk of bleeding, and this risk increases with the combination of medications. Low-dose aspirin plus clopidogrel or other anti-platelet drug is recommended for up to one year after MI. Continuing the combination beyond that point is not common practice in all patients, since the increased bleeding risk may outweigh the benefits. However, the combination may be continued in certain patients, including those who received a left main artery stent, complex overlapping or branch-point stents, recurrent MI, in-stent clots or vascular events such as a transient ischemic attack while on aspirin alone. Even in these situations, an individual’s bleeding risk needs to be considered to ensure safety.
Certain scoring systems have been developed to help cardiologists assess the risk of bleeding versus benefit. Ultimately, the decision to continue combination therapy is a complex one and requires discussions between you and your cardiologist.
Q: I am 62 years old and have a family history of early heart attack. Should I take aspirin?
A: There is little doubt that aspirin is appropriate after a cardiovascular (CV) event or stenting. In these cases, the benefits outweigh the bleeding risks. However, routine use of aspirin for prevention of a first CV event (“primary prevention”) has been controversial. Recent recommendations advise against using aspirin for this purpose.
Earlier this year, the U.S. Preventive Services Task Force (USPSTF) recommended low-dose aspirin for primary prevention of CVD in adults aged 50 to 69 who have a 10 percent or greater risk of a cardiac event within 10 years, are not at increased risk for bleeding and have a life expectancy of at least 10 years. The USPSTF did not find evidence to support the routine use of aspirin in adults younger than age 50, older than age 70 or at low-to-moderate CVD risk, since bleeding risk may outweigh CV benefit in these patients.
Cautious use of aspirin for primary prevention has recently been supported by two large randomized trials: ASCEND in diabetics and ARRIVE in non-diabetics with low-to-moderate risk and no previously diagnosed CV disease.
In ASCEND, the 12 percent relative reduction in CV events was offset by a 29 percent relative increase in bleeding, mostly in abdominal organs.
In ARRIVE, there was an insignificant 0.2 percent reduction in the rate of CV events, but a 50 percent relative increase in mostly non-serious bleeding in those taking aspirin.
These studies and others highlight the potential dangers of indiscriminate aspirin use and support the need for an individualized approach for each patient.