March Is Deep Vein Thrombosis Month

Prolonged sitting raises the risk of this dangerous health condition.

Guy playing video games late into the night.

On a long-distance plane trip these days, you sometimes see passengers doing seated exercises or taking a little walk up and down the aisle. "My doctor suggested it," they might say. "It's to reduce the risk of a blood clot."

These passengers are correct that sitting immobile for hours raises the risk of deep vein thrombosis (DVT). DVT occurs when a blood clot forms in a large vein, usually of the leg or pelvis. DVT can cause temporary or permanent damage to the vein where it forms. And if a clot breaks free and travels through the bloodstream into the lungs, it can result in a pulmonary embolism (PE), an arterial blockage that can be fatal.

But plane trips are far from the only situation that can lead to blood clots. Any circumstance that leaves us immobile, such as illness, injury or recovery from surgery, can raise the risk. The Centers for Disease Control and Prevention (CDC) says that many cases occur during or shortly after a hospital stay. And in December 2015, researchers from the University of Michigan even reported on "gamers thrombosis," which strikes video game aficionados, some of whom are quite young. Said study author Dr. Steven Kronick, "Gaming can be distracting and the hours can just melt away. Prolonged sitting is a risk factor for developing venothrombotic disease or blood clots. It doesn't matter if you're sitting on a very long air flight or on your living room couch. It's the same mechanism."

Other factors that raise the risk include obesity, a family history of blood clots, taking certain hormone-containing medications, previous injury to a vein, and a previous history of blood clots. Some experts also think smoking raises the risk. And we know that the risk of DVT/PE increases as we grow older.

Knowing the symptoms saves lives.

DVT/PE causes up to 100,000 deaths in the U.S. each year. Fortunately, DVT and PE are often successfully treated, if discovered right away. So it's important to know the symptoms.

Though not everyone who develops deep vein thrombosis will have noticeable symptoms, in some cases patients will experience swelling, pain, tenderness and redness of the skin in the area of the clot. Some patients describe the sensation as feeling like a pulled muscle or "charley horse" that doesn't go away. The skin may feel warm to the touch. See your doctor right away if you experience these symptoms. Treatment can prevent permanent damage to the affected vein and limb—and can prevent the clot from moving to the lung.

Unfortunately, when the clot moves to the lung, it is sometimes fatal. According to the CDC, "Sudden death is the first symptom in about 25 percent of people who have PE." But the National Heart, Lung and Blood Institute reports that recognizing the symptoms allows many patients to receive a prompt diagnosis and treatment, increasing their chance of survival and full recovery. Seek immediate medical attention if a person experiences symptoms of PE:

  • Shortness of breath or difficulty breathing.
  • Faster than normal or irregular heartbeat.
  • Anxiety.
  • Coughing up blood.
  • Very low blood pressure, lightheadedness or fainting.

Pulmonary embolism is an emergency. Seek help immediately.

Lowering the risk of deep vein thrombosis

Fortunately, we can lower our risk of DVT/PE. Discuss your risk factors with your healthcare provider and follow recommendations about ways to lower the risk. The first step in reducing the risk is to follow an all-around wellness lifestyle with plenty of exercise and maintaining a healthy weight. If your risk is high or if you have a history of blood clots, your doctor also may prescribe medications and perhaps recommend that you wear medical compression stockings.

Another way to lower the risk is to avoid prolonged sitting—and that includes everything from coast-to-coast plane trips to epic gaming sessions. If you're on a long plane, train or car trip, get up and walk around every two to three hours. If you're in a situation where you can't walk around, the CDC says to exercise your legs by:

  1. Raising and lowering your heels while keeping your toes on the floor.
  2. Raising and lowering your toes while keeping your heels on the floor.
  3. Tightening and releasing your leg muscles.

Wearing loose-fitting clothes also is recommended. So leave your skinny jeans in your suitcase and wear something more comfy on that plane trip.

Learn More

The Centers for Disease Control and Prevention and the nonprofit National Blood Clot Alliance have teamed up to create the Stop the Clot website (, where consumers can learn more about risk factors, prevention, diagnosis and treatment of blood clots.

The information in this article is not intended to replace the advice of your healthcare provider. Talk to your doctor about risk factors, prevention, diagnosis and treatment of deep vein thrombosis/pulmonary embolism.
