Published Online
on March 2, 2009

A more recent version of this article appeared on March 17, 2009

This Article Full Text (PDF) CME: Take the course for this article: Circulation: March 17, 2009, Volume 119, Number 10 All Versions of this Article: 119/10/1363    most recent CIRCULATIONAHA.108.816082v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Go, A. S. Search for Related Content PubMed PubMed Citation Articles by Go, A. S. Related Collections Acute Cerebral Infarction Arrhythmias, clinical electrophysiology, drugs Embolic stroke Epidemiology Related Article

Submitted on September 16, 2008
Accepted on December 15, 2008

Impact of Proteinuria and Glomerular Filtration Rate on Risk of Thromboembolism in Atrial Fibrillation. The Anticoagulation and Risk Factors in Atrial Fibrillation (ATRIA) Study

Alan S. Go MD^*, Margaret C. Fang MD, MPH, Natalia Udaltsova PhD, Yuchiao Chang PhD, Niela K. Pomernacki RD, Leila Borowsky MPH, Daniel E. Singer MD, for the ATRIA Study Investigators

From the Division of Research, Kaiser Permanente of Northern California, Oakland (A.S.G., N.U., N.K.P.); Departments of Epidemiology, Biostatistics, and Medicine, University of California at San Francisco (A.S.G., M.C.F.); and Clinical Epidemiology Unit, General Medicine Division, Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston (Y.C., L.B., D.E.S.).

^* To whom correspondence should be addressed. E-mail: Alan.S.Go{at}kp.org.

Background—Atrial fibrillation (AF) substantially increases the risk of ischemic stroke, but this risk varies among individual patients with AF. Existing risk stratification schemes have limited predictive ability. Chronic kidney disease is a major cardiovascular risk factor, but whether it independently increases the risk for ischemic stroke in persons with AF is unknown.

Methods and Results—We examined how chronic kidney disease (reduced glomerular filtration rate or proteinuria) affects the risk of thromboembolism off anticoagulation in patients with AF. We estimated glomerular filtration rate using the Modification of Diet in Renal Disease equation and proteinuria from urine dipstick results found in laboratory databases. Patient characteristics, warfarin use, and thromboembolic events were ascertained from clinical databases, with validation of thromboembolism by chart review. During 33 165 person-years off anticoagulation among 10 908 patients with AF, we observed 676 incident thromboembolic events. After adjustment for known risk factors for stroke and other confounders, proteinuria increased the risk of thromboembolism by 54% (relative risk, 1.54; 95% CI, 1.29 to 1.85), and there was a graded, increased risk of stroke associated with a progressively lower level of estimated glomerular filtration rate compared with a rate 60 mL · min^-1 · 1.73 m^-2: relative risk of 1.16 (95% CI, 0.95 to 1.40) for estimated glomerular filtration rate of 45 to 59 mL · min^-1 · 1.73 m^-2 and 1.39 (95% CI, 1.13 to 1.71) for estimated glomerular filtration rate <45 mL · min^-1 · 1.73 m^-2 (P=0.0082 for trend).

Conclusions—Chronic kidney disease increases the risk of thromboembolism in AF independently of other risk factors. Knowing the level of kidney function and the presence of proteinuria may improve risk stratification for decision making about the use of antithrombotic therapy for stroke prevention in AF.

Key words: atrial fibrillation • kidney failure, chronic • proteinuria • risk factors • stroke

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Clinical Summaries
Circulation 2009 119: 1353-1354. [Extract] [Full Text]

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