title: Renal Function and the Risk of Stroke and Bleeding in Patients With Atrial Fibrillation: An Observational Cohort Study.
abstract: We sought to determine the risk of stroke/thromboembolism and bleeding associated with reduced renal function in patients with atrial fibrillation and the risk of stroke and bleeding associated with warfarin treatment in specific estimated glomerular filtration rate (eGFR) groups.
  
  
  
  We conducted a register-based cohort study and included patients discharged with nonvalvular atrial fibrillation from 1997 to 2011 with available eGFR.
  
  
  
  A total of 17 349 patients were identified with eGFR available at baseline. All levels of lower eGFR were associated with higher risk of stroke/thromboembolism and bleeding. Use of warfarin was associated with higher bleeding risk in all eGFR groups; hazard ratios 1.23 (95% confidence interval [CI], 0.97-1.56), 1.26 (95% CI, 1.14-1.40), 1.18 (95% CI, 1.07-1.31), 1.11 (95% CI, 0.87-1.42), 2.01 (95% CI, 1.14-3.54) in patients with eGFR ≥90, 60 to 89, 30 to 59, 15 to 29, and <15 mL/min per 1.73 m2, respectively. Use of warfarin was associated with lower risk of stroke/thromboembolism in patients with eGFR ≥15 mL/min per 1.73 m2; hazard ratios 0.57 (95% CI, 0.43-0.76), 0.57 (95% CI, 0.51-0.64), 0.48 (95% CI, 0.44-0.54), 0.60 (95% CI, 0.45-0.80) in patients with eGFR ≥90, 60 to 89, 30 to 59, and 15 to 29 mL/min per 1.73 m2, respectively. Use of warfarin was not associated with lower risk of stroke/thromboembolism in patients with eGFR<15 mL/min per 1.73 m2; hazard ratio 1.18 (95% CI, 0.58-2.40).
  
  
  
  In patients with atrial fibrillation, the risk of stroke and bleeding was associated with levels of renal function. Warfarin treatment was associated with higher risk of bleeding in all eGFR groups and lower risk of stroke in patients with eGFR≥15 mL/min per 1.73 m2.
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.). andersnissenbonde@gmail.com.
authors.forename: Anders Nissen
authors.initials: AN
authors.lastname: Bonde
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.).
authors.forename: Gregory Y H
authors.initials: GY
authors.lastname: Lip
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.).
authors.forename: Anne-Lise
authors.initials: AL
authors.lastname: Kamper
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.).
authors.forename: Emil L
authors.initials: EL
authors.lastname: Fosbøl
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.).
authors.forename: Laila
authors.initials: L
authors.lastname: Staerk
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.).
authors.forename: Nicholas
authors.initials: N
authors.lastname: Carlson
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.).
authors.forename: Christian
authors.initials: C
authors.lastname: Torp-Pedersen
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.).
authors.forename: Gunnar
authors.initials: G
authors.lastname: Gislason
authors.affiliation: From the Department of Cardiology, Copenhagen University Hospital Gentofte, Denmark (A.N.B., L.S., N.C., G.G., J.B.O.); Institute of Cardiovascular Sciences, University of Birmingham, City Hospital, United Kingdom (G.Y.H.L.); Department of Nephrology (A.-L.K.) and Department of Cardiology (E.L.F.), Copenhagen University Hospital Rigshospitalet, Denmark; Department of Nephrology, Copenhagen University Hospital Herlev, Denmark (N.C.); Institute of Health, Science and Technology, Aalborg University, Aalborg, Denmark (C.T.-P.); The Danish Heart Foundation, Copenhagen, Denmark (G.G.); and The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark (G.G.).
authors.forename: Jonas Bjerring
authors.initials: JB
authors.lastname: Olesen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000009:adverse effects / Q000494:pharmacology*; D001281:Atrial Fibrillation / Q000453:epidemiology*; D015331:Cohort Studies; D015897:Comorbidity; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D020766:Intracranial Embolism / Q000453:epidemiology*; D020300:Intracranial Hemorrhages / Q000139:chemically induced / Q000453:epidemiology*; D020767:Intracranial Thrombosis / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D012042:Registries; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology*; D012306:Risk; D020521:Stroke / Q000453:epidemiology* / Q000517:prevention & control; D014859:Warfarin / Q000009:adverse effects / Q000494:pharmacology*
chemical_list: D000925:Anticoagulants; D014859:Warfarin
keywords: atrial fibrillation; glomerular filtration rate; renal insufficiency, chronic; stroke; thromboembolism