title: Hyperuricemia is an independent competing risk factor for atrial fibrillation.
abstract: BACKGROUND
  The relationship between serum uric acid (SUA) and atrial fibrillation (AF) remains unclear because many parameters and diseases influence AF. This study was conducted to clarify the role of hyperuricemia as an independent competing risk factor for AF in an apparently healthy general population.
  
  
  METHODS
  We retrospectively analyzed the medical records of 90,143 Japanese subjects who underwent annual regular health check-up in St. Luke's International Hospital, Tokyo, between January 2004 and June 2010. Of those subjects, 291 (0.32%) were identified as having AF by 12 leads electrocardiography. First, we analyzed 90,117 subjects to clarify the independent competing risk factors for AF and obtained odds ratios (ORs) by logistic regression analysis. Second, we excluded 40,825 subjects with hypertension, diabetes mellitus, dyslipidemia, chronic kidney disease, and current medication for hyperuricemia and/or gout, and we analyzed 49,292 subjects.
  
  
  RESULTS
  First, AF groups were significantly higher SUA level (OR: 1.35; 95% confidence interval (CI), 1.22-1.50) than non-AF group. OR of hyperuricemia (>7.0mg/dL of SUA) for AF was 2.75 (95% CI, 2.10-3.60). Second, after multiple adjustments, higher SUA level (OR: 1.53; 95% CI, 1.21-1.92) was a significantly independent competing risk factor for AF, as well as older age, male sex, higher body mass index, lower FEV1/FVC, and higher hemoglobin. OR of hyperuricemia for AF was 3.19 (95% CI, 1.81-5.62).
  
  
  CONCLUSIONS
  Hyperuricemia is an independent competing risk factor for AF. Further prospective intervention studies are needed to prove whether lowering SUA level might be important for preventing AF or not.
authors.affiliation: Department of Cardiology, St. Luke's International Hospital, Tokyo, Japan; Division of Regenerative Medicine and Therapeutics, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Sciences, Yonago, Japan; Department of Cardiology, Toranomon Hospital, Tokyo, Japan. Electronic address: kuwamasa728@gmail.com.
authors.forename: Masanari
authors.initials: M
authors.lastname: Kuwabara
authors.affiliation: Department of Cardiology, St. Luke's International Hospital, Tokyo, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Niwa
authors.affiliation: Department of Cardiology, St. Luke's International Hospital, Tokyo, Japan.
authors.forename: Shuzo
authors.initials: S
authors.lastname: Nishihara
authors.affiliation: Department of Cardiology, St. Luke's International Hospital, Tokyo, Japan.
authors.forename: Yutaro
authors.initials: Y
authors.lastname: Nishi
authors.affiliation: Center for Clinical Epidemiology, St. Luke's International University, Tokyo, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Takahashi
authors.affiliation: Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Shimotsuke, Japan.
authors.forename: Kazuomi
authors.initials: K
authors.lastname: Kario
authors.affiliation: Division of Cardiovascular Medicine, Endocrinology and Metabolism, Department of Molecular Medicine and Therapeutics, Faculty of Medicine, Tottori University, Yonago, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: The Cardiovascular Institute, Tokyo, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamashita
authors.affiliation: Division of Regenerative Medicine and Therapeutics, Institute of Regenerative Medicine and Biofunction, Tottori University Graduate School of Medical Sciences, Yonago, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Hisatome
mesh_terms: D001281:Atrial Fibrillation / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D033461:Hyperuricemia / Q000097:blood / Q000150:complications* / Q000453:epidemiology; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D014041:Tokyo / Q000453:epidemiology; D014527:Uric Acid / Q000097:blood*
chemical_list: D014527:Uric Acid
keywords: Atrial fibrillation; Clinical epidemiology; Competing risk factor; Uric acid