ABSTRACT
Thrombophilia testing is now commonplace. However, testing for heritable thrombophilia
does not predict outcome in response to oral anticoagulant therapy. At present there
is no conclusive evidence that recurrence on treatment with warfarin with a target
International Normalized Ratio of 2.5 is greater in patients with laboratory evidence
of heritable thrombophilia compared with those without. Similarly, there is no conclusive
evidence that patients with laboratory evidence of heritable thrombophilia are more
likely to suffer an earlier recurrence once treatment is stopped. Therefore, the management
of patients with familial thrombotic disease and patients with laboratory evidence
of heritable thrombophilia should be influenced by their personal and family history
rather than the results of laboratory investigations. There is no doubt that the relative
risk of thrombosis is increased in affected family members of thrombosis-prone families
but this translates to a relatively low absolute risk per year, and long-term primary
prophylaxis with oral anticoagulant therapy is not justified in the majority. Evidence
of antiphospholipid syndrome is associated with an increased risk of recurrent venous
thromboembolism, but there is still uncertainty as to the optimal intensity and duration
of oral anticoagulant therapy after an episode of arterial or venous thrombosis in
patients with detectable antiphospholipid activity.
KEYWORDS
Thrombophilia - anticoagulation - thrombosis
