Do Varicose Veins Cause Deep Vein Thrombosis?

If you’re living with varicose veins then you’re very familiar with their symptoms—aching, swelling, bulging veins, and discoloration of the leg. Since varicose veins are chronic and progressive, you may be worried about developing new complications without treatment.Photo courtesy of Klara Kulikova from

One condition you may be concerned about is deep vein thrombosis. Varicose veins do indeed raise the risk of deep vein thrombosis. In fact, having varicose veins doubles your risk of developing deep vein thrombosis over someone with no varicose veins. It is important, however, to put that in a proper perspective which we will do in a moment.

To understand the possible connection between varicose veins and deep vein thrombosis, we’ll look at:

  • Varicose veins and blood clots
  • What is deep vein thrombosis?
  • Symptoms of deep vein thrombosis
  • Risk factors of deep vein thrombosis

Varicose Veins and Blood Clots

It’s estimated that up to 40% of women and 25% of men live with varicose veins and their symptoms. Some of these symptoms are immediately obvious while others are “invisible” and go unnoticed. While the symptoms may be manageable for a while, varicose veins are a progressive and chronic disease that will only get worse with time.

Along with the tell-tale dark, twisted varicose veins, other symptoms include:

So what is it about varicose veins that cause these symptoms? When functioning normally, blood gets sent back to the heart from the legs thanks to one-way valves that open and close to keep the blood moving. 

But sometimes these valves stop working properly. This results in blood pooling in the legs and causes inflammation of the veins and the surrounding skin as well as blood leaking from the veins into the surrounding skin. This is what causes the visible and invisible symptoms of varicose veins.

Symptoms and complications can become worse in more extreme cases. Along with bleeding veins, you can also develop blood clots that can worsen your symptoms as well as lead to new, more serious, complications. To prevent situations like these, it’s best to seek treatment for your varicose veins earlier rather than later. 

Varicose Veins Double the Risk of a Deep Vein Thrombosis 

The reasons varicose veins contribute to deep vein thrombosis are not completely understood.  We do know that because the blood of varicose veins doesn’t circulate normally as it should,  moving upwards towards the heart past one-way valves within the veins, but instead rather “churns” within veins, i.e. moving up the veins and then falling down again past failed valves.  

This slowly moving blood is prone to develop clots much like sludge in a backwater of a stream or in a pond. These smaller clots within the veins of the skin can spread into deeper muscular veins and cause deep vein thrombosis. In fact, they double the risk of deep vein of a deep vein thrombosis over someone who has no varicose veins.

This is especially important if considering that around one-quarter of adults have varicose veins. Most develop this due to genetics. Other risk factors for varicose veins include:

  • Being female
  • Being over the age of 65
  • Sitting or standing for long periods of time
  • Being overweight
  • Having had several pregnancies 

What is deep vein thrombosis?

Deep vein thrombosis is a condition in which a blood clot, also known as a thrombus, develops in one or more deep veins within your body. While they can develop anywhere in the body, they are most likely to occur within the deep veins of your legs. 

What makes deep vein thrombosis especially dangerous is the possibility of a blood clot coming loose within the vein. If this happens, the blood clot will travel through your bloodstream and eventually arrive in your lungs. 

This causes a pulmonary embolism, which is when a lung artery becomes blocked. Pulmonary embolisms can result in permanent lung damage, low blood oxygen levels, as well as damage to other organs due to a lack of oxygen. A large clot or multiple clots can be life-threatening.

Symptoms of Deep Vein Thrombosis

Deep vein thrombosis symptoms are similar to those caused by varicose veins but are generally more severe. This makes sense when you consider that both involve preventing blood from flowing normally through the vein and back to the heart.

Deep vein thrombosis symptoms include:

  • Pain in the leg
  • Swelling of the affected leg
  • Discoloration of the leg
  • Feelings of warmth in the leg

These are the most common symptoms of deep vein thrombosis. However, you should keep in mind that sometimes the condition can occur without any symptoms presenting themselves.

Risk Factors for Deep Vein Thrombosis

Like the symptoms of deep vein thrombosis, the condition also has risk factors in common with varicose veins. These include genetics, pregnancy, being overweight, age, and sitting for long periods of time.

Other risk factors for deep vein thrombosis include:

  • Using hormonal birth control
  • Using hormone replacement therapy
  • Cancer
  • Inflammatory bowel disease
  • Injury to your veins
  • Prolonged immobilization
  • Recent surgery

Talk to your doctor if you have any of these risk factors. They’re best equipped to treat the condition as well as prevent complications such as pulmonary embolism.

An Important Word of Perspective Regarding Varicose Veins and their Risk of Developing Deep Vein Thrombosis

Varicose veins double the risk of an individual developing deep vein thrombosis.  However, to put that in perspective, the average American has a 1 in 10,000 chance of developing a deep vein thrombosis every year. Patients with varicose veins have twice that risk, making it a 1 in 5,000 chance every year. 

In other words, the risk is still low. So we don’t recommend treatment of varicose veins primarily because of this risk unless we find they are among those who have already experienced clots within the surface veins as these tend to recur and can indeed spread to deep veins. 

Most patients with varicose veins are treated because their veins are currently causing:

  • Pain
  • Swelling
  • Disfigurement

These symptoms will only worsen with time. Patients who have experienced complications such as clotting, bleeding discoloration, leg ulcers are treated to reduce the likelihood of recurrence of the complication. 

Contact us at East Tennessee Vein Clinic to get help for your varicose veins. We treat varicose veins differently by eliminating the entire network of failed veins, not just large visibly bulging veins. You can contact us online, or call us at 865.686.0507 or toll-free at 866.281.VEIN.

“Everyone at E. TN. Vein Clinic is very professional and caring. You can’t find a better doctor than Dr. Douglass. He explains procedures so well that you are very comfortable with going through the procedures. I wouldn’t change a thing at this office. The whole staff makes you feel so comfortable.”

- S. H., Gatlinburg, TN