title: Intrinsic clotting factors in dependency of age, sex, body mass index, and oral contraceptives: definition and risk of elevated clotting factor levels.
abstract: Elevated clotting factors have been demonstrated to be a risk factor for venous thromboembolism (VTE). The aim of our study was to investigate the impact of age, sex, body mass index, and oral contraceptives on the clotting factor activities of factors VIII, IX, XI, and XII and their impact on the cutoff definition and risk of VTE associated with elevated clotting factors. Factor VIII, IX, XI, and XII activities were measured in 499 blood donors and 286 patients with VTE. Age and body mass index predicted significantly and independently the clotting factor activities of factors VIII, IX, and XI, whereas use of oral contraceptives predicted factor IX, XI, and XII levels. Percentiles of clotting factor activities, which are often used for the cutoff definition of elevated clotting factors, varied due to the effect of age, body mass index, and oral contraceptives. The adjusted odds ratios for VTE were 10.3 [95% confidence interval (CI) 5.1-20.7], 6.1 (95% CI 3.1-12.0), and 3.3 (95% CI 1.9-5.8) for elevated factors VIII, IX, and XI, respectively. Furthermore, our study demonstrates for the first time that elevated factor XII is associated with an increased risk of VTE (adjusted odds ratio 2.9, 95% CI 1.6-5.3).
authors.affiliation: Division of Vascular Medicine and Haemostaseology, University Hospital Frankfurt, 60590 Frankfurt, Germany. beate.luxembourg@kgu.de
authors.forename: Beate
authors.initials: B
authors.lastname: Luxembourg
authors.forename: Joern
authors.initials: J
authors.lastname: Schmitt
authors.forename: Marek
authors.initials: M
authors.lastname: Humpich
authors.forename: Matthias
authors.initials: M
authors.lastname: Glowatzki
authors.forename: Erhard
authors.initials: E
authors.lastname: Seifried
authors.forename: Edelgard
authors.initials: E
authors.lastname: Lindhoff-Last
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001779:Blood Coagulation Factors / Q000032:analysis*; D015992:Body Mass Index; D003276:Contraceptives, Oral; D005164:Factor IX / Q000032:analysis; D005169:Factor VIII / Q000032:analysis; D005172:Factor XI / Q000032:analysis; D005174:Factor XII / Q000032:analysis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D012737:Sex Factors; D054556:Venous Thromboembolism / Q000097:blood* / Q000453:epidemiology; D055815:Young Adult
chemical_list: D001779:Blood Coagulation Factors; D003276:Contraceptives, Oral; D005169:Factor VIII; D005164:Factor IX; D005174:Factor XII; D005172:Factor XI