Clinical outcome in Japanese elderly patients with non-valvular atrial fibrillation taking warfarin: A single-center observational study
Thrombosis Research, 06/08/2012
Clinical Article
Naganuma M et al. – The results demonstrate that a target prothrombin time–international normalized ratio (PT–INR) of 2.0 and a range of 1.5–2.5 may be safe for elderly Japanese patients with non–valvular atrial fibrillation (AF).
Methods- The authorsconducted a cohort study of 845 consecutive non–valvular AF patients ≥70years of age who were taking warfarin (median age, 74years; 30.5% women) with a median follow–up period of 27months (4–69months).
- Of these patients, 29.7% had a history of stoke/transient ischemic attack (TIA), and 73.1% of the patients had a CHADS2 score≥2.
- The occurrence of thromboembolic events, including ischemic stroke, TIA and other systemic embolisms, and major bleeding events were validated through a review of medical records.
- The incidence of thromboembolic and major bleeding events were 3.8 and 2.1% per year, respectively.
- A higher incidence of both events was observed in patients with a CHADS2 score ≥3.
- The multivariate analysis showed that prior stroke/TIA (odds ratio 1.7, 95% CI 1.0–2.7) and diabetes (odds ratio 1.7, 95% CI 1.0–2.8) were independent risks of thromoembolic events.
- A HAS–BLED score ≥3 represented a risk for major bleeding (hazard ratio 2.8, 95% CI 1.7–4.6).
- A PT–INR of 1.5–2.5 indicated a low incidence of thromboembolic and major bleeding events in patients with a CHADS2 score ≥2.



