title: Dabigatran use in Danish atrial fibrillation patients in 2011: a nationwide study.
abstract: OBJECTIVE
  Dabigatran was recently approved for anticoagulation in patients with atrial fibrillation (AF); data regarding real-world use, comparative effectiveness and safety are sparse.
  
  
  METHODS
  Pharmacoepidemiological cohort study. METHODS/SETTINGS: From nationwide registers, we identified patients with an in-hospital or outpatient-clinic AF diagnosis who claimed a prescription of dabigatran 110 or 150 mg, or vitamin K antagonist (VKA), between 22 August and 31 December 2011. HRs of thromboembolic events (ischaemic stroke, transitory ischaemic attack and peripheral artery embolism) and bleedings were estimated using Cox regression analyses in all patients and stratified by previous VKA use.
  
  
  RESULTS
  Overall, 1612 (3.1%) and 1114 (2.1%) patients claimed a prescription of dabigatran 110 and 150 mg, and 49640 (94.8%) of VKA. Patients treated with dabigatran 150 mg were younger with less comorbidity than those treated with dabigatran 110 mg and VKA, as were VKA naïve patients compared with previous VKA users. Recommendations set by the European Medicine Agency (EMA) for dabigatran were met in 90.3% and 55.5% of patients treated with 110 and 150 mg. Patients treated with 150 mg dabigatran, who did not fulfil the recommendations by EMA, were >80 years, patients with liver or kidney disease, patients with previous bleeding. Compared with VKA, the thromboembolic risk associated with dabigatran 110 and 150 mg was HR 3.52 (1.40 to 8.84) and 5.79 (1.81 to 18.56) in previous VKA users, and HR 0.95(0.47 to 1.91) and 1.14(0.60 to 2.16) in VKA naïve patients. Bleeding risk was increased in previous VKA users receiving dabigatran 110 mg, but not in patients with 150 mg dabigatran, nor in the VKA naïve users.
  
  
  CONCLUSIONS
  Deviations from the recommended use of dabigatran were frequent among patients treated with 150 mg. With cautious interpretation, dabigatran use in VKA naïve patients seems safe. Increased risk of thromboembolism and bleeding with dabigatran among previous VKA users was unexpected and may reflect patient selection and 'drug switching' practices.
authors: Department of Cardiology, Copenhagen University Hospital Gentofte, Hellerup, Denmark.
authors: Rikke
authors: R
authors: Sørensen
authors: Gunnar
authors: G
authors: Gislason
authors: Christian
authors: C
authors: Torp-Pedersen
authors: Jonas Bjerring
authors: JB
authors: Olesen
authors: Emil L
authors: EL
authors: Fosbøl
authors: Morten W
authors: MW
authors: Hvidtfeldt
authors: Deniz
authors: D
authors: Karasoy
authors: Morten
authors: M
authors: Lamberts
authors: Mette
authors: M
authors: Charlot
authors: Lars
authors: L
authors: Køber
authors: Peter
authors: P
authors: Weeke
authors: Gregory Y H
authors: GY
authors: Lip
authors: Morten Lock
authors: ML
authors: Hansen
references: Neuroepidemiology. 2006;26(4):212-9
references: 16645320
references: Circulation. 2011 May 31;123(21):2363-72
references: 21576658
references: Ann Intern Med. 2007 Jun 19;146(12):857-67
references: 17577005
references: Br J Clin Pharmacol. 1997 Apr;43(4):429-33
references: 9146856
references: Semin Thromb Hemost. 2012 Feb;38(1):23-30
references: 22314600
references: Drug Metab Dispos. 2008 Feb;36(2):386-99
references: 18006647
references: Circ Cardiovasc Qual Outcomes. 2012 Sep 1;5(5):615-21
references: 22949490
references: BMJ. 2011 Jan 31;342:d124
references: 21282258
references: Europace. 2010 Oct;12(10):1360-420
references: 20876603
references: Eur J Heart Fail. 2010 Dec;12(12):1333-8
references: 20864482
references: N Engl J Med. 2009 Sep 17;361(12):1139-51
references: 19717844
references: Thromb Haemost. 2011 Oct;106(4):739-49
references: 21789337
references: Arch Intern Med. 2010 Sep 13;170(16):1433-41
references: 20837828
references: Circulation. 2007 May 29;115(21):2689-96
references: 17515465
references: Lancet. 2007 Oct 20;370(9596):1453-7
references: 18064739
references: Nephrol Dial Transplant. 2010 Mar;25(3):947-51
references: 19861312
references: J Thromb Haemost. 2011 Nov;9(11):2168-75
references: 21972820
references: N Engl J Med. 2011 Sep 15;365(11):981-92
references: 21870978
references: Clin Toxicol (Phila). 2012 Aug;50(7):571-3
references: 22800505
references: Ugeskr Laeger. 2001 Dec 31;164(1):33-7
references: 11810794
references: Circulation. 2010 Nov 30;122(22):2246-53
references: 21147728
references: J Neurosurg. 2012 May;116(5):1093-6
references: 22394293
references: Eur Heart J. 2012 Nov;33(21):2719-47
references: 22922413
references: N Engl J Med. 2011 Sep 8;365(10):883-91
references: 21830957
references: Dan Med Bull. 1997 Sep;44(4):445-8
references: 9377907