Atrial Fibrillation, Stroke Risk, and Warfarin Therapy Revisited

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.

2016 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS

“…3 -5 By 2030, 14 -17 million AF patients are anticipated in the European Union, with 120 000-215 000 newly diagnosed patients per year. 2,6,7 Estimates suggest an AF prevalence of approximately 3% in adults aged 20 years or older, 8,9 with greater prevalence in older persons 1 and in patients with conditions such as hypertension, heart failure, coronary artery disease (CAD), valvular heart disease, obesity, diabetes mellitus, or chronic kidney disease (CKD). 7,10 -15 The increase in AF prevalence can be attributed both to better detection of silent AF 16 -18 , alongside increasing age and conditions predisposing to AF.…”

Epidemiologic Aspects of Atrial Fibrillation in a Tertiary Hospital in a Sub-Saharan Africa Setting

“…This is due to the rapid urbanization that is associated with changes in life-style, which leads to the emergence of CVD risk such as hypertension, diabetes, dyslipidemia, obesity, tobacco use, and sedentarity [1] [2]. Atrial fibrillation (AF) is the most frequent sustained arrhythmia affecting 3% of the adult population [3] [4]. It carries a high morbidity and mortality due to its complications such as ischemic stroke, heart failure, and sudden death [5] [6] [7].…”

Defining the major health modifiers causing atrial fibrillation: a roadmap to underpin personalized prevention and treatment

“…Unfortunately, most of these current approaches are disconnected from our understanding of the major mechanisms that cause AF 1,13,14 1,2,7,19,20 Abstract | Despite remarkable advances in antiarrhythmic drugs, ablation procedures, and stroke-prevention strategies, atrial fibrillation (AF) remains an important cause of death and disability in middle-aged and elderly individuals. Unstructured management of patients with AF sharply contrasts with our detailed, although incomplete, knowledge of the mechanisms that cause AF and its complications.…”