Warfarin persistence among stroke patients with atrial fibrillation

• Published in: Thrombosis research Vol. 136; no. 4; pp. 744 - 748
• Main Authors: Björck, Fredrik, Renlund, Henrik, Svensson, Peter J, Själander, Anders
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.10.2015
• Subjects: Aged; Anticoagulants - administration & dosage; Anticoagulants - therapeutic use; Atrial fibrillation; Atrial Fibrillation - drug therapy; Clinical Medicine; Cohort Studies; Discontinuation; Female; Hematologi; Hematology; Hematology, Oncology and Palliative Medicine; Humans; Klinisk medicin; Male; Medical and Health Sciences; Medicin och hälsovetenskap; Neurologi; Neurology; Persistence; Risk Factors; Stroke; Stroke - drug therapy; Treatment; Warfarin; Warfarin - administration & dosage; Warfarin - therapeutic use; CHF; Stroke; Warfarin; Chronic Heart Failure; The Swedish National Patient Register; Discontinuation; AF; TIA; CDR; Persistence; Cause of Death Register; NPR; Treatment; Transient Ischemic Attack; Chronic Obstructive Pulmonary Disease; Atrial Fibrillation; COPD; Atrial fibrillation
• ISSN: 0049-3848; 1879-2472; 1879-2472
• DOI: 10.1016/j.thromres.2015.07.028

Abstract Introduction Warfarin treatment discontinuation is significant among patients with atrial fibrillation (AF). For AF patients with stroke a warfarin persistence rate of 0.45 after 2 years has previously been reported. No consistent predictors for discontinuation have been established. Aims Evaluation of warfarin persistence and variables associated with discontinuation, in a large Swedish cohort with unselected stroke/TIA patients with AF treated with warfarin. Materials and methods 4 583 patients with stroke/TIA and AF in the Swedish National Patient Register (NPR), from 1. Jan 2006 to 31. Dec 2011, were matched with the Swedish national quality register AuriculA. They were followed until treatment cessation, death or end of study. Baseline characteristics and CHA2 DS2 VASc score were retrieved from NPR. Treatment-time was retrieved from AuriculA. Results Overall proportion of warfarin persistence was 0.78 (95% confidence interval (CI) 0.76 to 0.80) after one year, 0.69 (95% CI 0.67 to 0.71) after 2 years and 0.47 (95% CI 0.43 to 0.51) after 5 years. Variables clearly associated with higher discontinuation were dementia (hazard ratio (HR) 2.22, CI 1.51-3.27) and alcohol abuse (HR 1.66, CI 1.19-2.33). Chronic obstructive pulmonary disease (COPD), cancer and chronic heart failure (CHF) were each associated with over 20% increased risk of treatment discontinuation. Higher CHA2 DS2 VASc score and start-age lead to lower persistence (p < 0.001). Conclusions Persistence to warfarin in unselected stroke/TIA patients with AF is in Sweden greater than previously reported. Lower persistence is found among patients with high treatment start-age, incidence of dementia, alcohol abuse, cancer, CHF, COPD and/or high CHA2 DS2 VASc score.