Varicose Veins and Clots: Chicken or the egg?

It's known that clot in deep veins (DVT) causes inflammation and venous valve malfunction which can cause Varicose Veins.  The question now is whether this process can happen in the reverse order:  in other words, do varicose veins lead to increased risk of developing a blood clot (DVT) in the future?

The answer is yes!

In a study published in JAMA on February 27, 2018, Dr. Chang and his colleagues followed 425,968 adults for little over 7 years.  Out of these 425,968, there were 212,984 patients in the varicose veins and the rest were used a "control group."  

The varicose veins group had higher incidence rates than the control group for DVT [10,360 vs 1980 cases].  The risk of PE also went up with varicose veins [793 vs 451 cases].

Association of Varicose Veins With Incident Venous Thromboembolism and Peripheral Artery Disease. Journal of American Medical Association (JAMA). Shyue-Luen Chang, MD. et al. Feb 2018.