Which of the following statements best describes the options for oral anticoagulation for this patient?
A 78-year-old woman with hypertension undergoes an ECG and is found to have AF. She has read that AF increases the risk of stroke, and she asks if there is anything she can do to minimize this risk.
A. She is at low risk for thromboembolism; oral anticoagulation is not indicated B. She is at high risk for thromboembolism, but because she is older than 75 years, oral anticoagulation is absolutely contraindicated C. The combination of aspirin and clopidogrel is equivalent to warfarin in preventing thromboembolism in high-risk patients D. In patients 75 years or older, warfarin has been shown to be superior to aspirin for stroke prevention
In patients 75 years or older, warfarin has been shown to be superior to aspirin for stroke prevention-key concept/objective: to understand the treatment options to decrease the risk of thromboembolism in elderly patients with af the acc/aha/esc guidelines for the management of af stratify patients into groups at high, moderate, or low risk for thromboembolism, on the basis of a graded system of risk factors. high-risk factors are previous transient ischemic attack or stroke, mitral stenosis, or prosthetic heart valve; moderate-risk factors are age older than 75 years, hypertension, heart failure, left ventricular ejection fraction less than 35%, and diabetes mellitus. weaker risk factors are female gender, age 65 to 74 years, coronary artery disease, and thyrotoxicosis. warfarin is highly effective at reducing the risk of af-associated thromboembolism; such risk is reduced by more than 60% in select populations. it is appropriate for high-risk patients for whom anticoagulation is not contraindicated. warfarin is superior to the combination of aspirin and clopidogrel for the prevention of thromboembolic events in high-risk patients; thus, dual antiplatelet therapy should not be considered a substitute for warfarin. aspirin, either 81 or 325 mg daily, is moderately effective in stroke prevention, reducing the risk of stroke by approximately 20%; it is most appropriate for low-risk patients. intermediate-risk patients should be offered either warfarin (inr goal, 2 to 3) or aspirin, after balancing the risks and benefits for the individual patient. elderly patients (i.e., those 75 years of age or older) with af represent a particular therapeutic challenge, because advanced age is both a significant risk factor for thromboembolism, if the af is not treated, and a predictor of bleeding complications, if the patient is receiving anticoagulants. as such, oral anticoagulation is often underutilized in elderly patients, despite their high-risk profile. in a large randomized trial of patients 75 years or older, warfarin (inr goal, 2 to 3) was superior to aspirin (75 mg daily) for stroke prevention (yearly risk, 1.8% versus 3.8%, respectively), yet it was not associated with a significant increase in major hemorrhage compared with aspirin. to decrease the potential for bleeding, anticoagulation must be tightly monitored in elderly patients, and close attention must be paid to drug interactions that could potentially alter warfarin levels.