THROMBOEMBOLISM PROPHYLAXIS IN CHRONIC ATRIAL-FIBRILLATION - PRACTICEPATTERNS IN COMMUNITY AND TERTIARY-CARE HOSPITALS

Background and Purpose By 1992, several prospective trials established the efficacy of anticoagulation (AC) and to some extent antiplatelet (AP) agents in the prevention of stroke in the setting of atrial fibri llation (AF). The objective of this study was to determine whether pra ctice patterns in AF stroke prophylaxis reflect the findings of clinic al trials and whether stroke prophylaxis in AF differs between communi ty hospitals and tertiary teaching hospitals. Methods Retrospectively, 1250 hospital charts were reviewed. After patients who had undergone recent surgery, received treatment for malignancy, or were not in chro nic AF on discharge were eliminated, 651 remaining records were analyz ed for the presence of 26 clinical factors influencing the selection o f thromboembolism prophylaxis. Descriptive statistics and logistic reg ression were used to analyze the association between clinical and demo graphic factors and the decision to treat with AC, AP, or no specific antiembolic therapy. Results Of the 651 patients in AF, 273 (42%) rece ived no emboli prophylaxis while 219 (34%) were treated with AC (warfa rin), 146 (22%) were treated with AP, and 13 (2%) received both agents . Patients discharged in AF from community hospitals were significantl y less likely to be treated with either AC or AP agents than patients discharged from tertiary centers. A strong bias against thromboembolis m prophylaxis with either AC or AP agents in AF existed with age over 45 years. Multivariate logistic regression indicated that the decision to treat was associated only with the presence of prosthetic valve, h istory of prior stroke, mitral disease, and absence of a recent, gastr ointestinal bleed or occult blood in stool. Even after adjustment for these factors, a significant bias against treatment with either AC or AP agents with advancing age and discharge from community hospitals re mained. Conclusions Thromboembolism prophylaxis with either AC or AP a gents is underutilized in the setting of AF. Furthermore, factors know n to increase the risk of embolization in AF such as age, hypertension , diabetes, and heart disease were not associated with decisions to tr eat with either AP or AC agents. This study suggests that the use of c linical guidelines suggested by trials of thromboembolism prophylaxis in AF could reduce the incidence of stroke.