Is an oral anticoagulant necessary for young atrial fibrillation patients with a CHA₂DS₂-VASc score of 1 (Men) or 2 (Women)?

Background--Recent studies demonstrated that oral anticoagulants (OACs) should be considered for patients with atrial fibrillation and 1 risk factor in addition to sex. Because age is an important determinant of ischemic stroke, the strategy for stroke prevention may be different for these patients in different age strata. The aim of this study was to investigate whether OACs should be considered for patients aged 20 to 49 years with atrial fibrillation and a CHA₂DS₂-VASc score of 1 (men) or 2 (women). Methods and Results--Using the Taiwan National Health Insurance Research Database, 7374 male patients with atrial fibrillation and a CHA₂DS₂-VASc score of 1 and 4461 female patients with atrial fibrillation and a CHA₂DS₂-VASc score of 2 and all without antithrombotic therapies were identified and stratified into 3 groups by age. The threshold for the initiation of OACs for stroke prevention was set at a stroke rate of 1.7% per year for warfarin and 0.9% per year for non-vitamin K antagonist OACs. Among male patients aged 20 to 49 years with a CHA₂DS₂-VASc score of 1, the risk of ischemic stroke was 1.30% per year and ranged from 0.94% per year for those with hypertension to 1.71% for those with congestive heart failure. Among female patients aged 20 to 49 years with a CHA₂DS₂-VASc score of 2, the risk of ischemic stroke was 1.40% per year and ranged from 1.11% per year for those with hypertension to 1.67% for those with congestive heart failure. Conclusions--For atrial fibrillation patients aged 20 to 49 years with 1 risk factor in addition to sex, non-vitamin K antagonist OACs should be considered for stroke prevention to minimize the risk of a potentially fatal or disabling event.