DVT concerns and running.

I am a healthy 48-year-old veteran of 12 marathons. I have been running for about 12 years. I am 6 feet 3 inches, 200 lbs. I am seeking information about deep vein thrombosis (DVT)/pulmonary emboli associated with running. I ran the Detroit Marathon and then 3 weeks later developed pleuritic chest pain and unilateral pleural effusion. I spent 4 days in the hospital, treated for presumptive pneumonia, but I had no fever. The pain was unimaginable. After 6 weeks off, I started running again. I ran a 19-miler and had the same thing happen a week later--this time bilateral effusions, incredibly painful. My chest CT was normal. I was again hospitalized for 4 days, and had a total of 12 days of IV antibiotics with resolution of symptoms. I started running again with a drop in mileage, to about 20 or 25 miles/week.

Similar symptoms began three months later. Then a month later I developed DVT in my left leg. The chest CT showed multiple emboli, but I was having no chest symptoms. I am currently on Coumadin and asymptomatic. I will probably be on this for life. I had laboratory work done from a hematologist, and all thrombophilia tests were normal. I was seen at the Mayo Clinic for their opinion, and they don't have an explanation. I am an OB/GYN and I am stumped as well. I had a normal colonoscopy 2 years ago. There is no family history of thrombosis, and no recent long car rides or flights. My hematologist (a non-runner!) thinks it may be due to trauma induced by running. I am not buying that as I have never heard of it.

My questions are: 1) Could running induce DVT? 2) Is it reasonable to think that I will get back to distance running? 3) Can anyone think of any other reason for me to have thrombosis? I really would like to start running again, but obviously I want to be safe, too.

Stanley Martin, MD

It appears that you most likely have idiopathic DVT/PE. DVT/PE cuts across different disciplines. I discussed your case with two of our vascular specialists with expertise in clotting. One is also a runner. Both of them think that it is very unlikely that your running was somehow causative for your DVT/PE. Neither one has ever seen a runner/athlete in whom this has occurred. The literature on this subject is a bit confusing. The studies of acute exercise on blood clotting have produced discrepant results--some suggest an increased clotting tendency but others suggest a decreased tendency. The studies of the chronic effect of exercise training on clotting tendency are somewhat more consistent and generally suggest a decreased tendency. Acute exercise is associated with an increased risk of acute MI [heart attack]. In conditioned subjects this risk is very low. The mechanism is not known. The general feeling is that the acute exercise somehow promotes plaque rupture, which as you know involves platelet activation, etc. But the platelet activation may all be secondary and not a primary event. In the exercise literature there are also a few anecdotal reports of acute venous thrombosis with DVT/PE occurring in a runner, but most of these cases have a reason, such as an identifiable coagulation disorder. The two clotting specialists I consulted thought it would be possible for a runner to develop a clot in the setting of severe dehydration or in association with a stress fracture with fat embolus. If there is nothing in your history to support these possibilities they thought it unlikely that your running was causative. Certainly idiopathic DVT/PE occurs in healthy adults who don't exercise.

Is it reasonable to get back to distance running and is it safe? Since you are a physician you are familiar with addressing this type of issue. No one can provide you with a 100% certain answer. I think that you have to carefully consider all of the opinions of the various physicians whom you have seen. If a physician has specifically advised you not to run, I would discuss the issue further with that person to see what he or she is basing his/her opinion on. As indicated above it is important that you have follow-up testing to be certain that there is no evidence of an underlying disorder. If all of these things check out OK, and especially if you are on Coumadin, it would seem that your risk for a recurrence would be low.

If you decide to return to running, some simple common-sense measures would be to start out easy, increase your training gradually, pay particular attention to hydration, and avoid competitive events for a substantial length of time to simply see how the training goes first.

Todd Miller, MD