title: Low-dose aspirin and rupture of abdominal aortic aneurysm.
abstract: The use of low-dose aspirin (acetylsalicylic acid [ASA]) has been suggested to attenuate growth of abdominal aortic aneurysms (AAAs), yet solid clinical evidence of this hypothesis is still missing. This study aimed to investigate whether preadmission ASA use influenced the risk of presenting with rupture of AAA (rAAA) on hospital admission and subsequent 30-day case fatality.
  
  
  
  There were 4010 patients with an incident diagnosis of rAAA and 4010 age- and sex-matched AAA patients identified in the Danish National Registry of Patients. Data on comorbidity, concomitant drug use, primary health care utilization, socioeconomic status, and vital status were obtained from nationwide health care and administrative registries.
  
  
  
  Preadmission ASA use was identified for 1815 (45.3%) rAAA patients and 2111 (52.6%) AAA patients, corresponding to a crude odds ratio for rAAA in ASA users of 0.72 (95% confidence interval [CI], 0.66-0.79) compared with nonusers. However, after adjustment for possible confounders, no association between ASA use and the risk of rAAA was found (adjusted odds ratio, 0.97; 95% CI, 0.86-1.08). The aggregated 30-day rAAA case-fatality rate for users of ASA was 66.0% compared with 56.9% for nonusers, corresponding to an adjusted mortality rate ratio of 1.16 (95% CI, 1.06-1.27).
  
  
  
  Preadmission ASA use is not associated with an altered risk of AAA rupture but seems to be associated with a worse prognosis after rupture of AAA.
authors.affiliation: Department of Vascular Surgery, Viborg Regional Hospital, Viborg, Denmark; Department of Clinical Epidemiology, Institute of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark. Electronic address: holger.wemmelund@midt.rm.dk.
authors.forename: Holger
authors.initials: H
authors.lastname: Wemmelund
authors.affiliation: Elitary Research Centre of Individualised Medicine in Arterial Disease (CIMA), Department of Cardiothoracic and Vascular Surgery, Odense University Hospital, Odense, Denmark.
authors.forename: Trine M M
authors.initials: TM
authors.lastname: Jørgensen
authors.affiliation: Department of Vascular Surgery, Viborg Regional Hospital, Viborg, Denmark.
authors.forename: Annette
authors.initials: A
authors.lastname: Høgh
authors.affiliation: Department of Vascular Surgery, Viborg Regional Hospital, Viborg, Denmark.
authors.forename: Carsten
authors.initials: C
authors.lastname: Behr-Rasmussen
authors.affiliation: Department of Clinical Epidemiology, Institute of Clinical Medicine, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Søren P
authors.initials: SP
authors.lastname: Johnsen
authors.affiliation: Department of Vascular Surgery, Viborg Regional Hospital, Viborg, Denmark; Elitary Research Centre of Individualised Medicine in Arterial Disease (CIMA), Department of Cardiothoracic and Vascular Surgery, Odense University Hospital, Odense, Denmark.
authors.forename: Jes S
authors.initials: JS
authors.lastname: Lindholt
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000401:mortality; D001019:Aortic Rupture / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000401:mortality; D001241:Aspirin / Q000008:administration & dosage / Q000009:adverse effects*; D016022:Case-Control Studies; D003718:Denmark / Q000453:epidemiology; D018450:Disease Progression; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D016016:Proportional Hazards Models; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors
chemical_list: D001241:Aspirin