title: Venous thromboembolism in young women; role of thrombophilic mutations and oral contraceptive use.
abstract: OBJECTIVE
  The interaction between the R506Q mutation of factor V and the G20210A mutation of prothrombin with oral contraceptives on venous thromboembolism was evaluated.
  
  
  RESULTS
  Three hundred and one women of reproductive age who had venous thromboembolism (140 while using oral contraceptives) and 650 healthy women (173 on oral contraceptives at presentation) were examined. Of the patients, 19.3% were carriers of R506Q (two homozygotes) and 9.6% were heterozygous carriers of G20210A; eight patients (2.7%) were heterozygous for both mutations. Among controls, 2.9% were carriers of R506Q, 3.1% of G20210A, while one case was a heterozygous carrier of both mutations. The relative risk (odds ratio) associated with carriership of R506Q or G20210A mutations was 10.3 and 4.7, respectively; it was 45.6 in carriers of both mutations. The odds ratio of using oral contraceptives in the absence of both mutations was 2.4. The odds ratios according to oral contraceptives use and the presence of R506Q or G20210A or both mutations were 41.0, 58.6 and 86.5, respectively. While the odds ratio for R506Q remains elevated (8.9) in non-oral contraceptive users, the odds ratio for G20210A was 2.0 and did not reach statistical significance.
  
  
  CONCLUSIONS
  Our data showed a strong interaction between oral contraceptive use and the presence of either R506Q or G20210A mutations. In non-oral contraceptive users the risk of venous thromboembolism was significantly increased in carriers of R506Q but not in those with the G20210A mutation.
authors.affiliation: Unità di Ricerca Clinica sulla Trombofilia Marino Golinelli - Dipartimento Cardiovascolare, Divisione di Angiologia, Azienda Ospedaliera di Bologna, Policlinico S. Orsola-Malpighi, Bologna, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Legnani
authors.forename: G
authors.initials: G
authors.lastname: Palareti
authors.forename: G
authors.initials: G
authors.lastname: Guazzaloca
authors.forename: B
authors.initials: B
authors.lastname: Cosmi
authors.forename: B
authors.initials: B
authors.lastname: Lunghi
authors.forename: F
authors.initials: F
authors.lastname: Bernardi
authors.forename: S
authors.initials: S
authors.lastname: Coccheri
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D003276:Contraceptives, Oral / Q000009:adverse effects*; D005165:Factor V / Q000187:drug effects / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D006720:Homozygote; D006801:Humans; D007866:Leg / Q000098:blood supply* / Q000473:pathology; D008875:Middle Aged; D017354:Point Mutation / Q000187:drug effects / Q000235:genetics; D015995:Prevalence; D011488:Protein Deficiency / Q000150:complications / Q000235:genetics; D011516:Prothrombin / Q000187:drug effects / Q000235:genetics; D012008:Recurrence; D012307:Risk Factors; D017211:Treatment Failure; D020246:Venous Thrombosis / Q000139:chemically induced* / Q000453:epidemiology / Q000235:genetics*; D016387:Women's Health
chemical_list: D003276:Contraceptives, Oral; D005165:Factor V; D011516:Prothrombin