Abstract 19549: National Adherence to Guidelines for Stroke Prevention in Atrial Fibrillation
Introduction: Atrial fibrillation (AF) carries a significant stroke risk, which can be estimated by the CHADS2 scoring system. ACC/AHA guidelines suggest that low risk patients can safely be treated with aspirin (ASA) while wafarin therapy benefits higher risk patients.
Hypothesis: Anticoagulation use in AF does not follow national risk stratification guidelines.
Methods: We used two databases (National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey) to estimate the annual number of outpatient clinic visits nation-wide from 2005-2007 for patients with AF and their prescribed medications. Specific past history data for all of the CHADS2 risk elements was collected for each visit in the study period. Patients were stratified by CHADS2 score of 0 (low risk), 1 (moderate risk) and 2-6 (high risk). Use of ASA and warfarin therapy was computed as a percentage of all visits by risk group. Logistic regression analysis compared medication use between 2005 and 2007 for each CHADS2 category.
Results: From 2005-2007, office visits nationally for patients with AF increased from 3.2 million with CHADS2 score of 0, 7.88 million with a CHADS2 score of 1, to 12.18 million with CHADS2 score of 2-6. Between 32.3% and 37.9% of patient visits in all CHADS2 groups did not have anticoagulant therapy prescribed, without a decrease between 2005 and 2007. 55.3% of lowest risk patient visits included warfarin therapy. Only 58.3% of highest risk patient visits included warfarin therapy.
Conclusions: Warfarin therapy does not adhere to national guidelines. Despite strong evidence to support warfarin therapy in high risk patients, only 58.3% of patients receive recommended therapy. Although data suggests bleeding risk outweighs thrombosis risk in low risk patients, 55.3% are still receiving warfarin. Additional understanding as to why these discrepancies exist is needed for optimal patient care.
- © 2010 by American Heart Association, Inc.