Edema in the legs is the result of a process that involves the veins, and a DVT is also the result of a process that involves the veins.
So how likely, then, can having edema in the legs cause a deep vein thrombosis?
“No, edema cannot cause a DVT,” says Susan L. Besser, MD, with Mercy Medical Center, Baltimore, and Diplomate American Board of Obesity Medicine and board certified by the American Board of Family Medicine.
Dr. Besser adds, “A DVT is due to a blood clot within a vein. Edema of the leg is due to excess fluid in the tissue of the leg but not in the vessels.”
So how, then, are veins associated
with the buildup of this excess fluid?
In the case of congestive heart failure, which is very common all over the world, the heart fails to pump an adequate amount of blood throughout the body.
Veins transport used (de-oxygenated) blood back to the lungs for re-oxygenation, where it then goes to the heart to be pumped out again. The veins in your legs and elsewhere in the body have this job.
In congestive heart failure, things get backed up, or congested. This backup causes the returning blood flow, from the veins in the legs, to become backed up. Excess fluid results, but it makes its way into the tissue around these veins.
Another common cause of leg edema is excessive sitting. Though excessive sitting increases the risk of a DVT, this higher risk is not induced by way of the edema.
Rather, it’s induced by the prolonged pooling of the blood (from too many hours sitting) in the veins.
High sodium intake in salt-sensitive people is another cause of edema in the legs. But again, this does not affect the clotting factor of venous blood.
Causes and Increased Risk Factors for DVT
• Not edema
• Lack of exercise, sedentary lifestyle
• Prolonged immobility during air and vehicular travel
• Excessive bedrest
• Recent surgery, especially abdominal or joint replacement
• Birth control pills
• The “sitting disease”