Visibly swollen and distorted veins that lie just beneath the skin, mainly in the legs
Varicose veins affect about 3 in 10 adults and are more common with increasing age. Although the condition may cause discomfort and appear unsightly, it is not usually harmful to health.
Varicose veins mainly affect the legs. Normally, blood in the legs collects in the superficial veins just below the skin. These veins empty the blood into deep-lying veins through small perforating veins. The deep-lying veins carry blood back towards the heart. Contraction of the leg muscles helps to pump the blood in the veins upwards to the heart, even when you are standing, and the veins have one-way valves to stop blood from flowing backwards into the legs. If the valves in the perforating vein do not close adequately, the blood flows back into the superficial veins. The pressure of returning blood eventually causes these veins to become swollen and distorted, and they are then known as varicose veins. If left untreated, the condition often worsens.
Varicose veins can develop in other parts of the body as a complication of chronic liver disease, which raises blood pressure in the portal veins (see Portal hypertension and varices). The rise in blood pressure may cause veins to become swollen at the lower end of the oesophagus, and, in some cases, around the rectum (see Haemorrhoids).
Varicose veins may be associated with an inherited weakness of the valves in the veins. The female hormone progesterone, which causes the veins to dilate, may encourage the formation of varicose veins, and the condition is therefore more common in women, especially during pregnancy (see Common complaints of normal pregnancy). In addition, increased pressure is placed on the veins in the pelvic region during pregnancy as the uterus gradually grows larger. Other factors that increase the risk of developing varicose veins include being overweight and having an occupation that involves standing for long periods with little walking.
Sometimes, varicose veins are caused by a blood clot blocking a deep vein (see Deep vein thrombosis).
If you develop varicose veins in the legs, you may have the following symptoms:
Easily visible, blue, swollen, distorted veins that bulge beneath the skin and are more prominent when standing.
Aching or pain in the affected leg, especially after prolonged standing.
In severe cases, the skin over a varicose vein, usually in the ankle area, becomes thin, dry, and itchy. Eventually, ulceration may occur (see Leg ulcer).
Your doctor will examine the affected area while you are standing, when the veins are usually more prominent and easily visible. You may have Doppler ultrasound scanning to assess the direction of blood flow in the veins of the leg. If the veins are varicose, the blood will appear to flow backwards.
In the majority of cases, varicose veins do not require medical treatment, and you may be able to relieve discomfort using self-help measures (see Coping with varicose veins).
Treatment is usually carried out only if the veins become painful or especially unsightly or if the skin becomes ulcerated. There are several ways of treating varicose veins, and you may need to discuss these options with your doctor. If your varicose veins are small and below the knee, your doctor may recommend that the veins be injected with a solution to make their walls stick together and thus prevent blood from entering them. For varicose veins above the knee, the usual treatment is to tie off the perforating veins so that blood does not enter the varicose vein. If the entire vein is varicose, it may be treated surgically (see Treating varicose veins). Even after treatment, varicose veins may recur, and treatment may need to be repeated.
From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.