Net Clinical Benefit of Warfarin Therapy in Very Elderly Chinese Patients with Atrial Fibrillation.
Circ Arrhythm Electrophysiol. 2014 Mar 7;
Authors: Siu CW, Tse HF
BACKGROUND: -Little is known about the net clinical benefit of warfarin therapy in very elder patients with atrial fibrillation (AF).
METHODS AND RESULTS: -We studied 2,339 Chinese patients with non-valvular AF aged ≥80 years: 1,805 with no antithrombotic therapy and 534 on warfarin therapy. Patients were stratified according to their CHA2DS2-VASc and HAS-BLED score. The primary endpoint was a composite of hospital admission with ischemic stroke, or death. After 2.2-year follow-up (5,199 patient-years), a primary endpoint had occurred for 1,861 patients (79.6%): 66.9% in patients on warfarin (66.9%) compared with 80.8% in patients with no antithrombotic therapy (80.8%) (HR: 0.53, 95% CI:0.48-0.58, p<0.001). This was related to substantially better mortality rate (HR: 0.40, 95%CI: 0.37-0.45, p<0.0001) and ischemic stroke rate (HR: 0.64, 95%CI: 0.54-0.77, p<0.0001) amongst patients on warfarin. For the net clinical benefit, 510 ischemic strokes and 42 ICH were recorded. The annual incidence of ischemic stroke and ICH was 11.3%/year and 0.6%/year respectively in patients prescribed no antithrombotic therapy, and 7.1%/year and 1.1%/year respectively in those prescribed warfarin. The adjusted net clinical benefit favored warfarin for all elderly patients, and the best net-benefit from warfarin was in those with high stroke and ICH risk. In these high-risk patients, warfarin therapy was associated with 7.2 to 8.0 fewer events per 100 patient-years compared with no antithrombotic therapy.
CONCLUSIONS: -In very elderly patients with AF, warfarin therapy is associated with lower death and ischemic stroke, and an overall net-clinical benefit.
PMID: 24610776 [PubMed - as supplied by publisher]