title: Impact on Outcomes of Changing Treatment Guideline Recommendations for Stroke Prevention in Atrial Fibrillation: A Nationwide Cohort Study.
abstract: To investigate the impact on outcomes of changing treatment guideline recommendations by comparing the proportion of patients with atrial fibrillation (AF) recommended oral anticoagulants (OACs) under the 2011 and 2014 American College of Cardiology/American Heart Association (ACC/AHA) guidelines.
  
  
  
  We used the "National Health Insurance Research Database" in Taiwan, which included 354,649 patients with AF from January 1, 1996 through December 31, 2011. Patients with a CHADS2 (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, and prior stroke or transient ischemic attack) score of 2 or more and a CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, prior stroke or transient ischemic attack, vascular disease, age 65-74 years, female sex category) score of 2 or more were considered to have a definitive indication for receiving OACs according to the 2011 and 2014 ACC/AHA guidelines, respectively.
  
  
  
  The percentages of patients with AF recommended OACs increased from 69.3% (n=245,598) under the 2011 guideline to 86.7% (n=307,640) under the new 2014 guidelines, an increment of 17.5% (95% CI, 17.4-17.6). Most women with AF (94.1%) and patients older than 65 years (97.2%) would receive OACs on the basis of the 2014 guidelines. Among patients previously not being recommended OACs in older guidelines, OAC use under the new guidelines was associated with a lower risk of adverse outcomes (ischemic stroke or intracranial hemorrhage or bleeding requiring blood transfusion or mortality) with an adjusted hazard ratio of 0.89 (95% CI, 0.85-0.94).
  
  
  
  In this nationwide cohort study, use of the 2014 guidelines led more patients with AF to receive OACs for stroke prevention, and this increased OAC use was associated with better outcomes. Better efforts to implement guidelines would lead to improved outcomes for patients with AF.
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Tze-Fan
authors.initials: TF
authors.lastname: Chao
authors.affiliation: Division of Hematology and Oncology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Public Health and School of Medicine, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chia-Jen
authors.initials: CJ
authors.lastname: Liu
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Ta-Chuan
authors.initials: TC
authors.lastname: Tuan
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan; General Clinical Research Center, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Kang-Ling
authors.initials: KL
authors.lastname: Wang
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yenn-Jiang
authors.initials: YJ
authors.lastname: Lin
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shih-Lin
authors.initials: SL
authors.lastname: Chang
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lo
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.affiliation: Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Tzeng-Ji
authors.initials: TJ
authors.lastname: Chen
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan; General Clinical Research Center, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Chern-En
authors.initials: CE
authors.lastname: Chiang
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Wan-Fang Hospital, and Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan. Electronic address: mhhsieh@tmu.edu.tw.
authors.forename: Ming-Hsiung
authors.initials: MH
authors.lastname: Hsieh
authors.affiliation: University of Birmingham Centre for Cardiovascular Sciences, City Hospital, Birmingham, UK.
authors.forename: Gregory Y H
authors.initials: GY
authors.lastname: Lip
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, and Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D000284:Administration, Oral; D017677:Age Distribution; D000368:Aged; D000925:Anticoagulants / Q000008:administration & dosage / Q000009:adverse effects / Q000592:standards*; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy* / Q000453:epidemiology; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology*; D005260:Female; D006333:Heart Failure / Q000453:epidemiology*; D006801:Humans; D006973:Hypertension / Q000453:epidemiology*; D007345:Insurance Claim Review / Q000706:statistics & numerical data; D020300:Intracranial Hemorrhages / Q000139:chemically induced / Q000209:etiology*; D008297:Male; D010043:Outcome and Process Assessment, Health Care / Q000706:statistics & numerical data; D017410:Practice Guidelines as Topic; D018570:Risk Assessment / Q000379:methods; D017678:Sex Distribution; D020521:Stroke / Q000139:chemically induced / Q000209:etiology*; D013624:Taiwan / Q000453:epidemiology; D014652:Vascular Diseases / Q000453:epidemiology; D014859:Warfarin / Q000008:administration & dosage / Q000009:adverse effects / Q000592:standards*
chemical_list: D000925:Anticoagulants; D014859:Warfarin