Deep vein thrombosis: thrombophilia was common.

Clinical bottom line (level 3b)

  1. Roughly a fifth of patients with first time DVTs had Activated Protein C resistance.
  2. In the community, about 5% of people have APC resistance.
Koster et al: Lancet 1993; 342: 1503-1506
Expires September 2003

The study

Case-control study with objective outcomes, not adjusted for confounding factors, not validated in an independent set of patients.

Setting: anticoagulation clinic, Holland

301 patients (aged mean 46 years, 60% female) first deep vein thrombosis

Excluded if
  • long-term anticoagulation treatment
  • hidtory of cancer
  • recurrent DVT
  • cirrhosis of the liver
  • vitamin K deficiency from malnutrition





    • Outcomes studied:
  • thrombophilia: Factor V Leiden all ages
  • thrombophilia: <45 years old
  • thrombophilia: <25 years old

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    thrombophilia: Factor V Leiden all ages ? / 21%
    (17% to 26%)
    thrombophilia: <45 years old ? / 23%
    (% to %)
    thrombophilia: <25 years old ? / 42%
    (% to %)

    Comments

    1. The finding of APC resistance was later found to be most commonly due to Factor V Leiden mutation
    2. It is uncertain as to the risks of APC resistance, and if any therapeutic changes should be made on the basis of it.

    Citation

    1. Koster V, et al: Venous thromboembolism due to poor anticoagulation response to APC. Lancet 1993; 342: 1503-1506
    Contributor: Bob Phillips and Chris Ball, September 2000
    Reviewer: Alex Gallus

    Clinical Question.
    Patient first DVT
    Intervention or Exposure risk factors
    Outcome thrombophilia