title: Meta-analysis of Vitamin D Deficiency and Risk of Atrial Fibrillation.
abstract: BACKGROUND
  There are accumulating studies investigating the association between vitamin D status and the risk of atrial fibrillation (AF). However, the results in these studies were inconsistent in regard to the role of vitamin D deficiency in predicting the development of AF.
  
  
  OBJECTIVE
  Vitamin D deficiency is associated increased risk of AF.
  
  
  METHODS
  Using PubMed and Embase databases, we searched for records published before March 2016. Additionally, a manual search was conducted using all review articles on this topic. Of the 587 initially identified records, 8 studies with a total of 27 307 patients were finally analyzed.
  
  
  RESULTS
  In the categorical variable analysis, vitamin D deficiency was associated with the occurrence of AF (odds ratio: 1.31, 95% confidence interval: 1.06-1.62, P = 0.01). In the continuous variable analysis, higher vitamin D levels appear to protect against the development of AF (odds ratio: 0.92, 95% confidence interval: 0.87-0.97, P = 0.002). However, the association is weak on the pooled analysis of prospective cohort studies focused on new-onset AF (P = 0.07 and 0.04), whereas the pooled analysis of case-control studies mainly assessing for chronic AF strongly support such an association (both P < 0.0001).
  
  
  CONCLUSIONS
  Vitamin D deficiency modestly increases the risk of AF. Further studies are needed to determine the if there is a direct causal relationship between vitamin D levels and AF and whether vitamin D supplements will prevent new-onset AF.
authors.affiliation: Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China.
authors.forename: Yajuan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Cardiac Arrhythmia Service, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: Chee Yuan
authors.initials: CY
authors.lastname: Ng
authors.affiliation: Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Wang
authors.affiliation: Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China.
authors.forename: Jianlong
authors.initials: J
authors.lastname: Wang
authors.affiliation: Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China.
authors.forename: Guangping
authors.initials: G
authors.lastname: Li
authors.affiliation: Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, People's Republic of China. liutongdoc@126.com.
authors.forename: Tong
authors.initials: T
authors.lastname: Liu
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014808:Vitamin D Deficiency / Q000175:diagnosis / Q000453:epidemiology*