Anticoagulation Therapy for Venous Thromboembolism, a review in Medscape General Medicine, stunningly concludes: “Anticoagulants have not been shown to be efficacious in reducing morbidity and/or mortality or safe in VTE treatment.”
Lesson one: Evidence based medicine (EBM) doesn’t always give us the answer.
The Medscape review points out that anticoagulant therapy became the standard based on a single small randomized controlled trial published in Lancet in 1960 which would be considered unacceptably flawed by today’s EBM standards. Moreover, subsequent studies in support of anticoagulation for venous thromboembolism (VTE) were of the sort the EBM crowd frowns on (observational studies, comparisons with historical controls, etc.).
But the Lancet study, flawed as it was, had striking results in favor of treatment. Anticoagulation became the standard, and it has since been considered unethical to do any more placebo controlled randomized trials. The totality of the subsequent evidence, although low level by EBM standards, is compelling. For me, the treatment of VTE with anticoagulants is justified even though it will probably never be “evidence based.” This thoughtful and thorough review in the Journal of Internal Medicine makes that point better than I can.
Lesson two: Financial conflicts of interest aren’t the only ones that need to be disclosed.
Note the following author information for the Medscape paper.Disclosure: David K. Cundiff has no significant financial interests or relationships to disclose. Mr. Cundiff has disclosed that he withdrew warfarin from a patient with lower limb deep vein thrombosis on the grounds that the risk of bleeding in this case seemed to be higher than the benefit of anticoagulant treatment. The patient later died of pulmonary embolism and Mr. Cundiff subsequently lost his medical license because of this case.
Kind of makes you want to read the paper a little more carefully, eh?