Staffan Björck1, Bo Palaszewski, Leif Friberg, Lennart Bergfeldt. 1. From the Department of Health Care Evaluation, Regionens Hus, Gothenburg, Sweden (S.B., B.P.); Department of Cardiology, Danderyd Hospital, Karolinska Institute, Stockholm, Sweden (L.F.); and Department of Molecular and Clinical Medicine/Cardiology, Sahlgrenska Academy, University of Gothenburg, Sweden (L.B.).
Abstract
BACKGROUND AND PURPOSE: Atrial fibrillation (AF) is a major risk factor for ischemic stroke. This study aims to update the knowledge about AF and associated stroke risk and benefits of anticoagulation. METHODS: We extracted data from the hospital, specialized outpatient, and primary healthcare and drug registries in a Swedish region with 1.56 million residents. We identified all individuals who had received an AF diagnosis during the previous 5 years; all stroke events during 2010; and patients with AF aged ≥50 years who had received warfarin during 2009. RESULTS: AF had been diagnosed in 38 446 subjects who were alive at the beginning of 2010 (prevalence of 3.2% in the adult [≥20 years] population); ≈46% received warfarin therapy. In 2010, there were 4565 ischemic stroke events and 861 intracranial hemorrhages. AF had been diagnosed in 38% of ischemic events (≥50% among those aged ≥80 years) and in 23% of intracranial hemorrhages. An AF diagnosis was often lacking in hospital discharge records after stroke events. Warfarin therapy was associated with an odds ratio of 0.50 (confidence interval, 0.43-0.57) for ischemic stroke and, despite an increased risk of intracranial hemorrhage, an odds ratio of 0.57 (confidence interval, 0.50-0.64) for the overall risk for stroke. CONCLUSIONS: AF is more common than present guidelines suggest. The attributable risk of AF for ischemic stroke increases with age and is close to that of hypertension in individuals aged ≥80 years. Because a majority of patients with AF with increased risk for stroke had not received anticoagulation therapy, there is a large potential for improvement.
BACKGROUND AND PURPOSE:Atrial fibrillation (AF) is a major risk factor for ischemic stroke. This study aims to update the knowledge about AF and associated stroke risk and benefits of anticoagulation. METHODS: We extracted data from the hospital, specialized outpatient, and primary healthcare and drug registries in a Swedish region with 1.56 million residents. We identified all individuals who had received an AF diagnosis during the previous 5 years; all stroke events during 2010; and patients with AF aged ≥50 years who had received warfarin during 2009. RESULTS:AF had been diagnosed in 38 446 subjects who were alive at the beginning of 2010 (prevalence of 3.2% in the adult [≥20 years] population); ≈46% received warfarin therapy. In 2010, there were 4565 ischemic stroke events and 861 intracranial hemorrhages. AF had been diagnosed in 38% of ischemic events (≥50% among those aged ≥80 years) and in 23% of intracranial hemorrhages. An AF diagnosis was often lacking in hospital discharge records after stroke events. Warfarin therapy was associated with an odds ratio of 0.50 (confidence interval, 0.43-0.57) for ischemic stroke and, despite an increased risk of intracranial hemorrhage, an odds ratio of 0.57 (confidence interval, 0.50-0.64) for the overall risk for stroke. CONCLUSIONS:AF is more common than present guidelines suggest. The attributable risk of AF for ischemic stroke increases with age and is close to that of hypertension in individuals aged ≥80 years. Because a majority of patients with AF with increased risk for stroke had not received anticoagulation therapy, there is a large potential for improvement.
Authors: Nicolae Done; Amanda M Roy; Yingzhe Yuan; Steven D Pizer; Adam J Rose; Julia C Prentice Journal: Health Serv Res Date: 2018-11-11 Impact factor: 3.402