Chronic venous insufficiency (CVI) is a common cause of leg pain and swelling, and is commonly associated with varicose veins. It occurs when the valves of the veins do not function properly, and the circulation of blood in the leg veins is impaired. CVI may affect up to 20 percent of adults. CVI can be caused by damaged valves in the veins or vein blockage. Both may be a result of deep vein thrombosis (DVT) or blood clots in the deep veins of the legs. If a clot forms in the superficial veins, there is a very low risk of DVT occurring.
Over time, CVI may result in varicose veins, swelling and discoloration of the legs, itching and the development of ulcers near the ankles. Vein problems are among the most common chronic conditions in North America. In fact, more people lose work time from vein disorders than from artery disease. By the age of 50, nearly 40 percent of women and 20 percent of men have significant leg vein problems. Spider veins occur much more frequently in women. It is estimated that at least 20 to 25 million Americans have varicose vein.