title: Risk factors and causes of sudden noncardiac death: A nationwide cohort study in Denmark.
abstract: BACKGROUND
  On the performance of an autopsy, sudden deaths may be divided into 2 classifications: (1) sudden cardiac deaths and (2) sudden noncardiac deaths (SNCDs). Families of SNCD victims should not be followed up as a means of searching for cardiac disease.
  
  
  OBJECTIVE
  The purpose of this study was to report the risk factors and causes of SNCD.
  
  
  METHODS
  We conducted a retrospective, nationwide study including all deaths between 2000 and 2006 of individuals aged 1-35 years and all deaths between 2007 and 2009 of individuals aged 1-49 years. Two physicians identified all sudden death cases through review of death certificates. Autopsy reports were collected. A multivariable logistic regression model was used to identify both clinical characteristics and risk factors associated with SNCD.
  
  
  RESULTS
  We identified 1039 autopsied cases of sudden death, of which 286 (28%) were classified as SNCD. The median age in the SNCD death population was 32 years. Increasing age was inversely associated with SNCD (odds ratio [OR] 0.93, 95% confidence interval [CI] 0.87-0.98). Female sex, in-hospital location, and the absence of cardiac comorbidities were positively associated with SNCD (OR 1.7, 95% CI 1.3-2.3; OR 3.0, 95% CI 2.0-4.4; and OR 4.3, 95% CI 2.5-7.4, respectively). The most common cause of SNCD was pulmonary disease (n = 115 [40%]).
  
  
  CONCLUSIONS
  Sudden death among individuals aged <50 years was caused by noncardiac diseases in 28% of cases. Risk factors were female sex, age, and the absence of cardiac comorbidities. These data may guide future strategies for the follow-up of family members of nonautopsied sudden death victims, improve risk stratification, and influence public health strategies.
authors.affiliation: Danish National Research Foundation Centre for Cardiac Arrhythmia (DARC), University of Copenhagen, Copenhagen, Denmark; Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Copenhagen 3 University Hospital, Rigshospitalet, Copenhagen, Denmark. Electronic address: bjarkerisgaard@gmail.com.
authors.forename: Bjarke
authors.initials: B
authors.lastname: Risgaard
authors.affiliation: Danish National Research Foundation Centre for Cardiac Arrhythmia (DARC), University of Copenhagen, Copenhagen, Denmark; Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Copenhagen 3 University Hospital, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Thomas Hadberg
authors.initials: TH
authors.lastname: Lynge
authors.affiliation: Department of Cardiology, Copenhagen University Hospital, Gentofte, Denmark.
authors.forename: Mads
authors.initials: M
authors.lastname: Wissenberg
authors.affiliation: Danish National Research Foundation Centre for Cardiac Arrhythmia (DARC), University of Copenhagen, Copenhagen, Denmark; Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Copenhagen 3 University Hospital, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Reza
authors.initials: R
authors.lastname: Jabbari
authors.affiliation: Danish National Research Foundation Centre for Cardiac Arrhythmia (DARC), University of Copenhagen, Copenhagen, Denmark; Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Copenhagen 3 University Hospital, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Glinge
authors.affiliation: Department of Cardiology, Copenhagen University Hospital, Gentofte, Denmark; The National Institute of Public Health, University of Southern Denmark, Copenhagen, Denmark.
authors.forename: Gunnar Hilmar
authors.initials: GH
authors.lastname: Gislason
authors.affiliation: Danish National Research Foundation Centre for Cardiac Arrhythmia (DARC), University of Copenhagen, Copenhagen, Denmark; Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Copenhagen 3 University Hospital, Rigshospitalet, Copenhagen, Denmark; Department of Medicine and Surgery, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Stig
authors.initials: S
authors.lastname: Haunsø
authors.affiliation: Danish National Research Foundation Centre for Cardiac Arrhythmia (DARC), University of Copenhagen, Copenhagen, Denmark; Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Copenhagen 3 University Hospital, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Bo Gregers
authors.initials: BG
authors.lastname: Winkel
authors.affiliation: Danish National Research Foundation Centre for Cardiac Arrhythmia (DARC), University of Copenhagen, Copenhagen, Denmark; Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Copenhagen 3 University Hospital, Rigshospitalet, Copenhagen, Denmark; Department of Medicine and Surgery, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Jacob
authors.initials: J
authors.lastname: Tfelt-Hansen
mesh_terms: D000328:Adult; D001344:Autopsy / Q000706:statistics & numerical data; D002423:Cause of Death; D002648:Child; D015897:Comorbidity; D003645:Death, Sudden / Q000453:epidemiology / Q000209:etiology; D016757:Death, Sudden, Cardiac / Q000453:epidemiology / Q000209:etiology; D003718:Denmark / Q000453:epidemiology; D003933:Diagnosis; D005192:Family Health; D005260:Female; D006331:Heart Diseases / Q000401:mortality; D006801:Humans; D007223:Infant; D008171:Lung Diseases / Q000401:mortality; D008297:Male; D008875:Middle Aged; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors
keywords: Autopsy; Registries; Sudden death; Sudden noncardiac death