title: Atrial ectopy and N-terminal pro-B-type natriuretic peptide as predictors of atrial fibrillation: a population-based cohort study.
abstract: OBJECTIVE
  The risk of incident atrial fibrillation (AF) can be estimated by clinical parameters in the Framingham AF risk model. Elevated N-terminal pro-B-type natriuretic peptide (NT-proBNP) and increased rate of premature atrial contractions (PACs) have been shown to be associated with AF, but the additive value of both of these biomarkers in the Framingham AF risk model has not been fully examined.
  
  
  RESULTS
  A total of 646 subjects from the Copenhagen Holter Study (mean age 64.4 ± 6.8 years, 41.6% women) with no history of prior AF, stroke or cardiovascular disease were followed for the diagnosis of incident AF or death (median follow-up time 14.4 years). Median NT-proBNP was 6.7 pmol/L (IQR: 3.6-13.5), median PAC count was 1.4 beats/h (IQR: 0.6-4.5), 71 (11.0%) subjects developed AF, and 244 (37.8%) died. Multiple Cox regression including Framingham AF risk score, log-transformed NT-proBNP, and log-transformed PAC showed a significant increase in AF hazard risk [hazard ratio (HR) 1.45, 95% confidence interval (CI) 1.14-1.85, P = 0.002; HR 1.23, 95% CI 1.09-1.39, P = 0.001]. The addition of PAC to the Framingham AF risk model significantly improved the time-dependent area under the receiver operating characteristic curve (AUC 65.6 vs. 72.6; P = 0.008), while the addition of NT-proBNP did not.
  
  
  CONCLUSIONS
  Atrial fibrillation risk discrimination was significantly improved by the addition of PAC to the Framingham AF risk model, but not by the addition of NT-proBNP.
authors.affiliation: Department of Cardiology, University Hospital of Bispebjerg, Copenhagen University Hospital of Bispebjerg, Bispebjerg Bakke 23, Copenhagen DK-2400, Denmark.
authors.forename: Preman
authors.initials: P
authors.lastname: Kumarathurai
authors.affiliation: Department of Cardiology, University Hospital of Bispebjerg, Copenhagen University Hospital of Bispebjerg, Bispebjerg Bakke 23, Copenhagen DK-2400, Denmark.
authors.forename: Mette R
authors.initials: MR
authors.lastname: Mouridsen
authors.affiliation: Department of Cardiology, University Hospital of Bispebjerg, Copenhagen University Hospital of Bispebjerg, Bispebjerg Bakke 23, Copenhagen DK-2400, Denmark.
authors.forename: Nick
authors.initials: N
authors.lastname: Mattsson
authors.affiliation: Department of Cardiology, University Hospital of Bispebjerg, Copenhagen University Hospital of Bispebjerg, Bispebjerg Bakke 23, Copenhagen DK-2400, Denmark.
authors.forename: Bjørn S
authors.initials: BS
authors.lastname: Larsen
authors.affiliation: Department of Cardiology, University Hospital of Bispebjerg, Copenhagen University Hospital of Bispebjerg, Bispebjerg Bakke 23, Copenhagen DK-2400, Denmark.
authors.forename: Olav W
authors.initials: OW
authors.lastname: Nielsen
authors.affiliation: Department of Biostatistics, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Gerds
authors.affiliation: Department of Cardiology, University Hospital of Bispebjerg, Copenhagen University Hospital of Bispebjerg, Bispebjerg Bakke 23, Copenhagen DK-2400, Denmark.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Sajadieh
mesh_terms: D000368:Aged; D019540:Area Under Curve; D001281:Atrial Fibrillation / Q000097:blood / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology; D018880:Atrial Premature Complexes / Q000453:epidemiology* / Q000401:mortality / Q000503:physiopathology; D015415:Biomarkers / Q000097:blood; D003718:Denmark / Q000453:epidemiology; D015716:Electrocardiography, Ambulatory; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D012372:ROC Curve; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors
chemical_list: D015415:Biomarkers; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
keywords: Arrhythmia; Atrial fibrillation; Epidemiology; Natriuretic peptides; Prediction models; Premature atrial contractions; Prognosis; Risk factors