The type and duration of treatment for pulmonary embolism can vary from person to person.
Pulmonary embolism (PE) is the presence of a blood clot (embolus) that blocks an artery in the lungs. Usually the clot comes from a piece of another blood clot inside a vein of the legs (deep vein thrombosis [DVT]) that has broken off and traveled to the lungs. Pulmonary emboli can range from very small and causing no symptoms to very large and causing symptoms of shortness of breath, chest pain, and dizziness. Some large pulmonary emboli can be fatal.
Blood-thinning medication is the main treatment for PE. How long to thin the blood depends on where the clot that went to the lung came from and why it formed.
Deciding how long treatment should last requires carefully weighing the risks and benefits of thinning blood for each individual person. Taking a blood thinner for too short a time can result in a clot returning after treatment is stopped. Taking a blood thinner for too long can increase the risk of bleeding as a side effect. The ideal duration of treatment depends on the individual’s risk of having another blood clot compared with the individual’s risk of bleeding, which the doctor takes into account. Currently, the recommended treatment duration ranges from a minimum of 3 months to a maximum of lifelong treatment.
A study published in the July 7, 2015, issue of JAMA addressed this question. This study was a randomized clinical trial involving more than 350 people who had a first-ever PE that was unprovoked. Unprovoked PE means there was no clear risk factor such as recent travel, surgery, or trauma to cause the clot. Having unprovoked PE means there is a higher risk of having another blood clot in the future compared with clots caused by a reversible, temporary risk factor (such as a long airplane ride).
The study compared the effects of giving blood-thinning medication for 6 months compared with 2 years. The study looked at how often people in each group had (1) another blood clot and (2) major bleeding as a side effect. The results showed a significantly lower risk of having another blood clot in the group that received the treatment for longer (2 years), without a major increase in bleeding risk.
If you have had a first-time PE without a clear cause, you may benefit from longer treatment with blood thinners than the usual 3 to 6 months. Talk to your doctor about your individual risks and benefits for taking blood thinners vs having another blood clot.
Centers for Disease Control and Preventionwww.cdc.gov/ncbddd/dvt/index.html
To find this and previous JAMA Patient Pages, go to the Patient Page link on JAMA’s website at jama.com. Many are available in English and Spanish. A Patient Page describing how blood thinners work was published in the December 18, 2013, issue; one on DVT was published in the May 26, 2015, issue; and one on PE was published in the February 6, 2013, issue.
Source: Couturaud F, Sanchez O, Pernod G, et al. Six months vs extended oral anticoagulation after a first episode of pulmonary embolism: the PADIS-PE randomized clinical trial. JAMA. doi:10.1001/jama.2015.7046.
Topic: Drug Therapy
Jin J. Treatment Duration for Pulmonary Embolism. JAMA. 2015;314(1):98. doi:10.1001/jama.2015.7431