The prevalence of atrial fibrillation increases with age as does the risk of stroke. In a meta-analysis of the early trials in atrial fibrillation, vitamin K antagonists were shown to reduce the risk of stroke by 68%. Despite the efficacy of anticoagulants, multiple studies have shown that they are under used in clinical practice, most notably among elderly persons with atrial fibrillation. The risk of major hemorrhage also increases with age. INR >4.0 is a major risk factor for hemorrhage. The optimal intensity of anticoagulation for stroke prevention in atrial fibrillation is an INR target range of 2.0 to 3.0.
Elaine M. Hylek, MD, MPH,
Associated Professor, Department of Medicine,
Boston University Medical Center (Boston, US)
"Living with anticoagulants" World Congress of Cardiology 2006, Barcelona, Chairpersons: J.M. Hasenkam( Aarhus), C. Schaefer (Ratingen), Nonprofit Organisation Symposium organized by ISMAAP (International Self-Monitoring Association for oral Anticaogulated Patients) September 3rd, 2006