title: [The Bavarian Thromboembolic Risk Cohort Study (BATER). Study protocol, state of the investigation and first results].
abstract: OBJECTIVE
  Familiar venous thromboembolic disease (VTE) is known to be related with factor V Leiden mutation (FVL), but also with other genetic markers. It is the objective to investigate of the BATER-study in a representative Bavarian cohort, and to assess whether they could predict VTE events. This paper shortly describes the study protocol, gives an overview of planned sub-studies, and provides first results of the historic cohort analysis.
  
  
  METHODS
  The baseline survey of the cohort study of Bavarian women aged 18-49 years (random sample from the population) was performed in two samples in 1996 and 1997. It was planned to estimate a prevalence and predictive value of potential markers of VTE in a historic--prospective as well as concurrent approach with annual follow-up of the cohort. This representative cohort should build a basis for nested case-control studies and serve as a reference group for other analytical epidemiological studies in young women. 1685 women were ascertained (response rate 61%), underwent an inquiry, and provided blood samples for a blood bank; for this paper, complete data are available from 1650 women. Laboratory parameters were measured to determine APC resistance, FVL-mutation, antithrombin-, protein C and S deficiency, and were correlated to the results of a detailed, life-time history of thrombembolic events.
  
  
  RESULTS
  The prevalence of FVL mutation in the sample was 5.7% (95% confidence interval 4.6-6.6%). Other genetic VTE risk markers were observed to be less frequent than 1%. The positive predictive value (pPV) of FVL mutation for a VTE event is about 7%, but for a positive family history of VTE (first grade relatives) 3% only.
  
  
  CONCLUSIONS
  VTE events are rare in the German population of young women, even in cases of FVL mutation. A positive family history is rarely associated with the occurrence of VTE in women under 50 years of age, and the predictive value of FVL mutation is low. Therefore, a screening for FVL mutation is not justified unless there is suspicion of a high VTE risk for other reasons.
authors.affiliation: Abteilung Hämostaseologie, Ludwig-Maximilians-Universität München.
authors.forename: W
authors.initials: W
authors.lastname: Schramm
authors.forename: L A
authors.initials: LA
authors.lastname: Heinemann
authors.forename: M
authors.initials: M
authors.lastname: Spannagl
authors.forename: A
authors.initials: A
authors.lastname: Dick
authors.forename: A
authors.initials: A
authors.lastname: Assmann
mesh_terms: D000293:Adolescent; D000328:Adult; D000428:Alcohol Drinking; D002985:Clinical Protocols; D015331:Cohort Studies; D016001:Confidence Intervals; D003276:Contraceptives, Oral; D005165:Factor V / Q000235:genetics*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008875:Middle Aged; D010298:Parity; D017354:Point Mutation; D012307:Risk Factors; D012907:Smoking; D013923:Thromboembolism / Q000453:epidemiology* / Q000235:genetics*; D020246:Venous Thrombosis / Q000453:epidemiology* / Q000235:genetics*
chemical_list: D003276:Contraceptives, Oral; C095381:factor V Leiden; D005165:Factor V