title: The incidence and mortality of acute thoracic aortic dissection: results from a whole nation study.
abstract: OBJECTIVE
  Acute thoracic aortic dissection (ATAD) is a devastating condition associated with a high mortality rate. Recent reports suggest that its incidence is rising. Utilizing nationwide data comprising the whole Icelandic population, we aimed to determine the incidence, mortality rate and time-dependent mortality risk of ATAD.
  
  
  METHODS
  Data were retrospectively collected using centralized hospital discharge registries, autopsy records and Cause of Death Registry in Iceland from 1992 to 2013.
  
  
  RESULTS
  Age- and gender-adjusted incidence of ATAD was 2.53/100 000/year, and no significant change in incidence was observed during the study period. The mean age was 66.9 ± 13.6 years and 66.0% (101/153) were Stanford type A. Of the whole group, 17.6% (27/153) died prior to hospital arrival, whereas the risk of death for patients who arrived alive to a hospital was 21.4% (27/126) within 24 h and 45.2% (57/126) at 30 days. During the course of the study, patients with type A dissection were more likely to undergo an operation and the management of type B dissection changed from open to endovascular repair. The 30-day mortality rate declined every year and the 5-year survival rate improved in the last third of the study.
  
  
  CONCLUSIONS
  The incidence of ATAD was 2.53/100 000/year and remained constant throughout the study, contradicting recent perceptions of a rising incidence. ATAD, type A in particular, remains a highly lethal condition: Over half of all patients die within 30 days of the index event. A reduced 30-day mortality rate and an increased long-term survival rate indicate improved overall outcomes in patients with this complex condition.
authors.affiliation: Department of Cardiothoracic Surgery, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: Inga H
authors.initials: IH
authors.lastname: Melvinsdottir
authors.affiliation: Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
authors.forename: Sigrun H
authors.initials: SH
authors.lastname: Lund
authors.affiliation: Faculty of Medicine, University of Iceland, Reykjavik, Iceland.|Department of Pathology, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: Bjarni A
authors.initials: BA
authors.lastname: Agnarsson
authors.affiliation: Department of Anesthesiology, Landspitali University Hospital, Reykjavik, Iceland.
authors.forename: Kristinn
authors.initials: K
authors.lastname: Sigvaldason
authors.affiliation: Department of Cardiothoracic Surgery, Landspitali University Hospital, Reykjavik, Iceland.|Faculty of Medicine, University of Iceland, Reykjavik, Iceland.
authors.forename: Tomas
authors.initials: T
authors.lastname: Gudbjartsson
authors.affiliation: Department of Cardiothoracic Surgery, Landspitali University Hospital, Reykjavik, Iceland arnarge@landspitali.is.|Section of Cardiac Surgery, Yale University School of Medicine, New Haven, CT, USA.|Department of Surgery, Veterans Affairs Connecticut Healthcare System, West Haven, CT, USA.
authors.forename: Arnar
authors.initials: A
authors.lastname: Geirsson
mesh_terms: D000367:Age Factors; D000368:Aged; D000784:Aortic Dissection / Q000453:epidemiology* / Q000401:mortality / Q000601:surgery; D017545:Aortic Aneurysm, Thoracic / Q000453:epidemiology* / Q000401:mortality / Q000601:surgery; D005260:Female; D006801:Humans; D015994:Incidence; D007494:Ireland / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D008297:Male; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012737:Sex Factors; D016019:Survival Analysis
keywords: Aortic dissection; Aortic surgery; Epidemiology; Population studies