title: Hyperuricemia and the risk of ischemic stroke in patients with atrial fibrillation--could it refine clinical risk stratification in AF?
abstract: BACKGROUND
  Although hyperuricemia has been reported to be a risk factor of stroke, the relationship between hyperuricemia and stroke in patients with atrial fibrillation (AF) remains uncertain. The goal of the present study was to investigate whether hyperuricemia could potentially refine clinical risk stratification in AF.
  
  
  METHODS
  This study used the "National Health Insurance Research Database" in Taiwan. A total of 7601 AF patients who did not receive antiplatelet agents or oral anticoagulants were identified as the study population. Hyperuricemia was defined as having at least one episode of gout attack necessitating long-term treatment with uric acid-lowering agents. The association between hyperuricemia and ischemic stroke was analyzed.
  
  
  RESULTS
  During the follow up of 3.0±2.7 years, 1116 patients (14.7%) experienced ischemic stroke with an annual rate of around 4.9%. Hyperuricemia significantly predicts stroke, with a hazard ratio (HR) of 1.280 after adjusting for CHA2DS2-VASc score and other comorbidities. Among the 376 patients with a CHA2DS2VASc score of 0, hyperuricemia can further stratify them into 2 groups with different stroke rates (7.1% versus 1.3%, p=0.020). The adjusted HR of hyperuricemia in predicting ischemic stroke diminished from 7.491 for patients with a CHA2DS2-VASc score of 0 to 1.659 for those with a score of 3, and became insignificant for patients with a score ≥4.
  
  
  CONCLUSIONS
  Hyperuricemia was a significant risk factor of stroke which could potentially refine the clinical risk stratification in AF. It deserves a prospective trial to investigate whether it would change the current strategy for stroke preventions using oral anticoagulants.
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan; 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, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Internal Medicine, National Yang-Ming University Hospital, I-Lan, Taiwan.
authors.forename: Chia-Jen
authors.initials: CJ
authors.lastname: Liu
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Su-Jung
authors.initials: SJ
authors.lastname: Chen
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan; Cardiovascular Research Center, National Yang-Ming University, 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, National Yang-Ming University, Taipei, Taiwan; 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, National Yang-Ming University, Taipei, Taiwan; 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, National Yang-Ming University, Taipei, Taiwan; 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, National Yang-Ming University, Taipei, Taiwan; Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Hu
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan; Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Ta-Chuan
authors.initials: TC
authors.lastname: Tuan
authors.affiliation: Department of Family Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Tzeng-Ji
authors.initials: TJ
authors.lastname: Chen
authors.affiliation: Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Internal Medicine, National Yang-Ming University Hospital, I-Lan, Taiwan; Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Hsuan-Ming
authors.initials: HM
authors.lastname: Tsao
authors.affiliation: Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan; Cardiovascular Research Center, National Yang-Ming University, Taipei, Taiwan. Electronic address: epsachen@ms41.hinet.net.
authors.forename: Shih-Ann
authors.initials: SA
authors.lastname: Chen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000453:epidemiology*; D002545:Brain Ischemia / Q000453:epidemiology*; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D033461:Hyperuricemia / Q000453:epidemiology*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009313:National Health Programs / Q000706:statistics & numerical data; D015995:Prevalence; D016016:Proportional Hazards Models; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology*; D013624:Taiwan / Q000453:epidemiology
keywords: Atrial fibrillation; CHA(2)DS(2)-VASc score; Hyperuricemia; Stroke