Abstract
INTRODUCTION: Direct oral anticoagulant agents (DOACs) are indicated for stroke prevention in patients with nonvalvular atrial fibrillation (NVAF). Reduced doses of DOACs are indicated in patients who have renal impairment and according to age and weight criteria. The aim of this study was to investigate the frequency, clinical factors, and impact on 1-year prognosis of underdosing DOACs. METHODS: Data of patients enrolled in the Jordan AF (JoFib) study and who were followed for 1 year was used to compare patients prescribed standard dose with those who were underdosed. RESULTS: There were 672 patients (76.2%) who were prescribed standard dose and 210 patients (23.8%) who were underdosed. Baseline characteristics were similar between the 2 groups. Factors associated with underdosing were enrollment from an outpatient vs hospital site, moderate- or high-risk HAS-BLED score, an abnormal left ventricular ejection fraction (LVEF <50%), a history of heart failure, or current use of diuretics. At 1 year, the incidence of all-cause mortality was 12.2% in standard dose vs 13.3% in the underdose group (P = .82), stroke or systemic embolism was 3.6% in the standard dose vs 3.8% in the underdose group (P = .67), and major bleeding was 2.2% in the standard dose vs 3.3% in the underdose group (P = .35). CONCLUSIONS: About (25%) of patients were underdosed. Factors associated with underdosing were outpatient (vs hospital) center enrollment, moderate- or high-risk HAS-BLED score, abnormal LVEF (<50%), history of heart failure, and current use of diuretics. There were no significant differences in the incidence of adverse events of mortality and major morbidity at 1-year follow-up between the standard dose and the underdose groups.