Dr. Sam Goldhaber discusses the optimal duration for anticoagulation.

Hello, this is Dr. Sam Goldhaber, President of NATF speaking to you on Clot Chronicles. Today, I’m going to discuss what is one of the major questions I’m asked in my office practice of vascular medicine and venous thrombosis, “what is the optimal duration of anticoagulation?”

The current guidelines say that if you have an identified reason for a pulmonary embolism (PE) or a DVT that the time course of anticoagulation should be limited for three to six months. If you have no identified reason for a DVT or a pulmonary embolism, then anticoagulation should be continued for an extended duration without any specific stop date.

Well, it turns out upon closer study of the available evidence  these guidelines are not really accurate, particularly for the types of DVT or pulmonary embolism where we think we have identified reasons. And, there are certain persisting risk factors or transient risk factors for a provoked DVT or pulmonary embolism that almost certainly do warrant extended duration of anticoagulation.

Some examples of this would include inflammatory bowel disease, such as ulcerative colitis or Crohn’s Disease. Those patients who have a persisting inflammation due to rheumatoid arthritis or psoriasis would be other examples of patients who should probably, on the basis of what we know, be considered for extended duration anticoagulation.

Guidelines are slow to change and we’re in a situation now where we, at our thrombosis research group, are trying to redefine and to re-imagine a more precise, patient-oriented approach to calculating the risks of a recurrent DVT or pulmonary embolism, and then making a recommendation for duration of anticoagulation based upon that risk.

With the advent of the non-vitamin K oral anticoagulants, in other words the NOACs, sometimes called the DOACs, we now have four different relatively novel oral anticoagulants that have a much lower bleeding complication rate than warfarin. This allows us to extend the duration of anticoagulation with a greater safety toward our patients.

In the general trend for patients with DVT or pulmonary embolism is to give longer courses of anticoagulation to prevent recurrence of DVT or pulmonary embolism. We need to work in the future towards developing more precise calculators as to the duration of this extension, and I think we will look forward to seeing honing down on more precision medicine with more specific suggestion for duration of anticoagulation in the future.

This Dr. Sam Goldhaber signing off for Clot Chronicles.