|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
From the University of Texas Health Science Center, San Antonio, TX.
Address correspondence and reprint requests to Dr Hart, University of Texas Health Science Center, 7703 Floyd Curl Dr., San Antonio, TX 78284 hartr{at}uthscsa.edu
Background: Absolute stroke rates vary widely among patients with nonvalvular atrial fibrillation. To balance the benefits and risks of chronic antithrombotic prophylaxis, it is important to estimate the absolute risk of stroke for individual patients.
Methods: Systematic review of studies using multivariate regression techniques to identify independent risk factors for stroke in patients with atrial fibrillation was conducted, and reports of absolute stroke rates in subgroups of patients with these risk factors collected. A summary estimate of the relative risk associated with each independent risk factor was calculated using maximum likelihood methods.
Results: Seven studies (including six entirely independent cohorts) were identified. Prior stroke/TIA (relative risk 2.5, 95% CI 1.8 to 3.5), increasing age (relative risk 1.5 per decade, 95% CI 1.3 to 1.7), a history of hypertension (relative risk 2.0, 95% CI 1.6 to 2.5), and diabetes mellitus (relative risk 1.7, 95% CI 1.4 to 2.0) were the strongest, most consistent independent risk factors. Observed absolute stroke rates for nonanticoagulated patients with single independent risk factors were in the range of 6 to 9% per year for prior stroke/TIA, 1.5 to 3% per year for history of hypertension, 1.5 to 3% per year for age >75, and 2.0 to 3.5% per year for diabetes. Female sex was inconsistently associated with stroke risk, whereas the evidence was inconclusive that either heart failure or coronary artery disease is independently predictive of stroke.
Conclusions: Four clinical features (prior stroke/TIA, advancing age, hypertension, diabetes) are consistent independent risk factors for stroke in atrial fibrillation patients. Prior stroke/TIA is the most powerful risk factor and reliably confers a high stroke risk (>5% per year, averaging 10% per year). Absolute stroke rates associated with other individual risk factors are difficult to precisely estimate from available data.
Supplemental data at www.neurology.org
*A list of members of the Stroke Risk in Atrial Fibrillation Working Group can be found in the Appendix.
The literature search was sponsored by the American Academy of Neurology Quality Standards Subcommittee as part of an update of its practice parameter on stroke prevention in atrial fibrillation.
Disclosure: The author reports no conflicts of interest.
Received November 6, 2006. Accepted in final form March 12, 2007.
This article has been cited by other articles:
![]() |
S. H. Hohnloser, G. Z. Duray, U. Baber, and J. L. Halperin Prevention of stroke in patients with atrial fibrillation: current strategies and future directions Eur. Heart J. Suppl., September 1, 2008; 10(suppl_H): H4 - H10. [Abstract] [Full Text] [PDF] |
||||
![]() |
Stroke Risk in Atrial Fibrillation Working Group Comparison of 12 Risk Stratification Schemes to Predict Stroke in Patients With Nonvalvular Atrial Fibrillation Stroke, June 1, 2008; 39(6): 1901 - 1910. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. S. Taggar, F. Marin, and G. Y.H. Lip Mortality in patients with atrial fibrillation: improving or not? Europace, April 1, 2008; 10(4): 389 - 390. [Full Text] [PDF] |
||||
![]() |
L. B. Goldstein and P. M. Rothwell Advances in Prevention and Health Services Delivery 2007 Stroke, February 1, 2008; 39(2): 258 - 260. [Full Text] [PDF] |
||||
![]() |
Risk Factors for Stroke in Patients with Atrial Fibrillation Journal Watch Neurology, January 8, 2008; 2008(108): 2 - 2. [Full Text] |
||||
![]() |
J. S. Taggar and G. Y.H. Lip Anticoagulation for elderly patients with atrial fibrillation: not to be neglected Europace, January 1, 2008; 10(1): 1 - 2. [Full Text] [PDF] |
||||
![]() |
Predictors of Stroke in Atrial Fibrillation Journal Watch (General), August 23, 2007; 2007(823): 4 - 4. [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |