A J Rose1, A Ozonoff, L E Henault, E M Hylek. 1. Center for Health Quality, Outcomes, and Economic Research, Bedford VA Medical Center, Bedford, MA 01730, USA. adamrose@bu.edu
Abstract
BACKGROUND: Previous studies of anticoagulation for atrial fibrillation (AF) have predominantly occurred in academic settings or randomized trials, limiting their generalizability. OBJECTIVE: To describe the management of patients with AF anticoagulated with warfarin in community-based practise. METHODS: We enrolled 3396 patients from 101 community-based practises in 38 states. Data included demographics, comorbidities, and International Normalized Ratio (INR) values. Outcomes included time in therapeutic INR range (TTR), stroke, and major hemorrhage. RESULTS: The mean TTR was 66.5%, but varied widely among patients: 37% had TTR above 75%, while 34% had TTR below 60%. The yearly rates of major hemorrhage and stroke were 1.90 per 100 person-years and 1.00 per 100 person-years. Four percent of patients (n = 127) were intentionally targeted to a lower INR, and spent 42.7% of time with an INR below 2.0, compared to 18.8% for patients with a 2.0-3.0 range (P < 0.001). Mean TTR for new warfarin users (57.5%) remained below that of prevalent users through the first six months. Patients with interruptions of warfarin therapy had lower TTR than all others (61.6% vs. 67.2%, P < 0.001), which corrected after deleting low peri-procedural INR values (67.0% vs. 67.4%, P = 0.73). CONCLUSIONS: Anticoagulation control varies widely among patients taking warfarin for AF. TTR is affected by new warfarin use, procedural interruptions, and INR target range. In this community-based cohort of predominantly prevalent warfarin users, rates of hemorrhage and stroke were low. The risk versus benefit of a lower INR target range to offset bleeding risk remains uncertain.
BACKGROUND: Previous studies of anticoagulation for atrial fibrillation (AF) have predominantly occurred in academic settings or randomized trials, limiting their generalizability. OBJECTIVE: To describe the management of patients with AF anticoagulated with warfarin in community-based practise. METHODS: We enrolled 3396 patients from 101 community-based practises in 38 states. Data included demographics, comorbidities, and International Normalized Ratio (INR) values. Outcomes included time in therapeutic INR range (TTR), stroke, and major hemorrhage. RESULTS: The mean TTR was 66.5%, but varied widely among patients: 37% had TTR above 75%, while 34% had TTR below 60%. The yearly rates of major hemorrhage and stroke were 1.90 per 100 person-years and 1.00 per 100 person-years. Four percent of patients (n = 127) were intentionally targeted to a lower INR, and spent 42.7% of time with an INR below 2.0, compared to 18.8% for patients with a 2.0-3.0 range (P < 0.001). Mean TTR for new warfarin users (57.5%) remained below that of prevalent users through the first six months. Patients with interruptions of warfarin therapy had lower TTR than all others (61.6% vs. 67.2%, P < 0.001), which corrected after deleting low peri-procedural INR values (67.0% vs. 67.4%, P = 0.73). CONCLUSIONS: Anticoagulation control varies widely among patients taking warfarin for AF. TTR is affected by new warfarin use, procedural interruptions, and INR target range. In this community-based cohort of predominantly prevalent warfarin users, rates of hemorrhage and stroke were low. The risk versus benefit of a lower INR target range to offset bleeding risk remains uncertain.
Authors: John J You; Daniel E Singer; Patricia A Howard; Deirdre A Lane; Mark H Eckman; Margaret C Fang; Elaine M Hylek; Sam Schulman; Alan S Go; Michael Hughes; Frederick A Spencer; Warren J Manning; Jonathan L Halperin; Gregory Y H Lip Journal: Chest Date: 2012-02 Impact factor: 9.410
Authors: Anne Holbrook; Sam Schulman; Daniel M Witt; Per Olav Vandvik; Jason Fish; Michael J Kovacs; Peter J Svensson; David L Veenstra; Mark Crowther; Gordon H Guyatt Journal: Chest Date: 2012-02 Impact factor: 9.410
Authors: Tetz C Lee; Min Qian; Gregory Y H Lip; Marco R Di Tullio; Susan Graham; Douglas L Mann; Koki Nakanishi; John R Teerlink; Ronald S Freudenberger; Ralph L Sacco; J P Mohr; Arthur J Labovitz; Piotr Ponikowski; Dirk J Lok; Conrado Estol; Stefan D Anker; Patrick M Pullicino; Richard Buchsbaum; Bruce Levin; John L P Thompson; Shunichi Homma; Siqin Ye Journal: Am J Cardiol Date: 2018-06-04 Impact factor: 2.778