title: Improved prognosis of thoracic aortic aneurysms: a population-based study.
abstract: BACKGROUND
  Managing thoracic aortic aneurysms identified incidentally by increased use of computed tomography, echocardiography, and magnetic resonance imaging is problematic, especially in the elderly.
  
  
  OBJECTIVE
  To ascertain whether the previously reported poor prognosis for individuals with thoracic aortic aneurysms has changed with better medical therapies and improved surgical techniques that can now be applied to aneurysm management.
  
  
  METHODS
  Population-based cohort study.
  
  
  METHODS
  All 133 patients with the diagnosis of degenerative thoracic aortic aneurysms among Olmsted County, Minnesota, residents between 1980 and 1994 compared with a previously reported cohort of similar patients between 1951 and 1980.
  
  
  METHODS
  The primary clinical end points were incidence, cumulative rupture risk, rupture risk as a function of aneurysm size, and survival.
  
  
  RESULTS
  In contrast to abdominal aortic aneurysms, for which men are affected predominately, 51% of thoracic aortic aneurysms were identified in women who were considerably older at recognition than men (mean age, 75.9 vs 62.8 years, respectively; P= .01). The overall incidence rate of 10.4 per 100000 person-years (95% confidence interval [CI], 8.6-12.2) between 1980 and 1994 was more than 3-fold higher than the rate from 1951 to 1980. The cumulative risk of rupture was 20% after 5 years. Seventy-nine percent of ruptures occurred in women (P= .01). The 5-year risk of rupture as a function of aneurysm size at recognition was 0% for aneurysms less than 4 cm in diameter, 16% (95% CI, 4%-28%) for those 4 to 5.9 cm, and 31% (95% CI, 5%-56%) for aneurysms 6 cm or more. Overall 5-year survival improved to 56% (95% CI, 48%-66%) between 1980 and 1994 compared with only 19% between 1951 and 1980 (P<.01).
  
  
  CONCLUSIONS
  In this population, elderly women represent an increasing portion of all patients with clinically recognized thoracic aortic aneurysms and constitute the majority of patients whose aneurysm eventually ruptures. Overall survival for thoracic aortic aneurysms has improved significantly in the past 15 years.
authors.affiliation: Division of Vascular Surgery, Mayo Clinic and Mayo Medical School, Rochester, Minn 55905, USA.
authors.forename: W D
authors.initials: WD
authors.lastname: Clouse
authors.forename: J W
authors.initials: JW
authors.lastname: Hallett
authors.forename: H V
authors.initials: HV
authors.lastname: Schaff
authors.forename: M M
authors.initials: MM
authors.lastname: Gayari
authors.forename: D M
authors.initials: DM
authors.lastname: Ilstrup
authors.forename: L J
authors.initials: LJ
authors.lastname: Melton
mesh_terms: D000368:Aged; D017542:Aneurysm, Ruptured / Q000453:epidemiology; D017545:Aortic Aneurysm, Thoracic / Q000175:diagnosis / Q000401:mortality* / Q000628:therapy; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011336:Probability; D011379:Prognosis; D012307:Risk Factors; D016019:Survival Analysis