title: Prevalence of established risk factors for venous thromboembolism according to age.
abstract: OBJECTIVE
  To date, the factors that contribute to the rise in venous thromboembolism (VTE) risk observed with higher ages remain unknown. Therefore, the aim of the present analysis was to study the distribution of established VTE risk factors in categories of manifestation age in a large cohort of VTE patients.
  
  
  METHODS
  Data were taken from the MAISTHRO (MAin-ISar-THROmbosis) registry, a cross-sectional study of patients with acute or documented history of VTE. The registry enrolled 1500 consecutive patients (869 females; median age, 43 years) with a first lower-extremity deep vein thrombosis or pulmonary embolism.
  
  
  RESULTS
  VTE was attributed to established risk factors in 76.6% of cases. By classifying patients into categories of VTE manifestation age, we observed a steep rise in the prevalence of malignancies with advancing age (ie, 1.3% of cases of VTE occurred under the age of 30 and 34.0% of VTE cases manifested over the age of 70; P < .001). In contrast, VTE was more likely to be related to thrombophilia, a family history of VTE, oral contraceptives, and pregnancy in younger patients. Hereditary thrombophilia was detected in 50% of VTE patients younger than 20 and in 21.8% over the age of 70 (P < .001). With regard to other VTE risk factors, the results were insignificant. In addition, we were unable to demonstrate an accumulation of common VTE risk factors among patients at higher ages.
  
  
  CONCLUSIONS
  The distribution of established VTE risk factors varies with the age of VTE manifestation. Future studies are needed to clarify the role of age-specific risk factors in the development of VTE and in the incidence gradient with aging.
authors.affiliation: Division of Vascular Medicine, Department of Internal Medicine, Goethe University Hospital, Frankfurt am Main, Germany. Electronic address: Birgit.Linnemann@kgu.de.
authors.forename: Birgit
authors.initials: B
authors.lastname: Linnemann
authors.affiliation: Division of Vascular Medicine, Department of Internal Medicine, Goethe University Hospital, Frankfurt am Main, Germany.
authors.forename: Lea
authors.initials: L
authors.lastname: Weingarz
authors.affiliation: Division of Vascular Medicine, Department of Internal Medicine, Goethe University Hospital, Frankfurt am Main, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Schindewolf
authors.affiliation: Division of Vascular Medicine, Department of Internal Medicine, Goethe University Hospital, Frankfurt am Main, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Schwonberg
authors.affiliation: Division of Vascular Medicine, Department of Internal Medicine, Goethe University Hospital, Frankfurt am Main, Germany.
authors.forename: Adele
authors.initials: A
authors.lastname: Weber
authors.affiliation: Institute of Biostatistics and Math, Modelling, Faculty of Medicine, Goethe University Hospital, Frankfurt am Main, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Herrmann
authors.affiliation: Division of Vascular Medicine, Department of Internal Medicine, Goethe University Hospital, Frankfurt am Main, Germany.
authors.forename: Edelgard
authors.initials: E
authors.lastname: Lindhoff-Last