Oral Anticoagulants and Nonvalvular A-fib: A Balancing Act

PATIENT ADHERENCE
Recent studies have indicated that adherence to anticoagulation therapy among A-fib patients drops by as much as 50% after one year of therapy.¹⁸ Causes are multifactorial and include complexity of treatment regimen, missed doses, patient unawareness of stroke risk, and fear of bleeding.¹⁹ Educating both patients and caregivers has been associated with significant improvements in medication compliance in these patients.¹⁹

Complex regimens
Treatment requirements, such as the serial laboratory testing and dosage adjustments associated with warfarin therapy, can be a major contributing factor to anticoagulation nonadherence.^18,20 In this regard, the newer once-daily medications that require limited follow-up may be good alternatives to warfarin.²¹

In patients for whom warfarin therapy is indicated, educational interventions may include

• Written information for patients and caregivers about medication regimens and dosage scheduling
• Reinforcement of treatment goals and outcomes
• Use of dosing aids such as dated and timed pill dispensers
• Incorporating caregiver support to help patients adhere to the medication regimen.

These interventions have been shown to improve adherence with complex treatment regimens.²²

Missed doses
Missing anticoagulant doses is not an uncommon occurrence, and patients should be advised of appropriate catch-up strategies when this occurs.

For dabigatran, the missed dose should be taken as soon as the patient remembers, but only if the next scheduled dose is more than six hours away.¹² For rivaroxaban, missed doses should be taken as soon as the patient remembers, and the next dose should resume as scheduled.¹³ For apixaban, a missed dose should be taken as soon as possible but not in combination with any other doses.¹⁴

For patients taking warfarin, a missed dose should be taken as soon as possible on the same day.²³ If more than 24 hours have elapsed, the patient should contact his or her health care provider before taking any medication.²³

Stroke risk
Adherence to anticoagulation therapy significantly reduces the risk for stroke among A-fib patients. Estimates suggest that anticoagulants can reduce stroke risk by as much as 68% in patients with A-fib.²⁴

Even with optimal anticoagulation therapy, however, stroke remains a major complication.²⁵ Through group sessions or patient education pamphlets, patients and caregivers should be informed about the high risk for stroke associated with A-fib and should know its early symptoms.²⁶ These include sudden onset of one or more of the following: confusion or difficulty understanding speech; numbness or weakness of the face or extremities, limited to one side of the body; severe headache; dizziness, loss of balance, or difficulty ambulating; and/or visual disturbances in one or both eyes.²⁶

Next page: Bleeding risk >>