Vein disease is a broad term for conditions where veins, usually in the legs, can’t efficiently return blood to the heart. The most common form is chronic venous insufficiency (CVI), which affects roughly 7 to 10% of adults and becomes significantly more common after age 50. It ranges from cosmetic spider veins to serious complications like open skin ulcers, and it tends to worsen over time without management.
How Healthy Veins Work and What Goes Wrong
Veins carry blood back toward the heart, working against gravity when you’re standing or sitting. Tiny one-way valves inside the veins open to let blood flow upward, then snap shut to prevent it from falling back down. Your calf muscles act as a pump, squeezing the veins with each step to push blood along.
Vein disease develops when this system breaks down. The valves weaken, lose their shape, or stop closing properly, allowing blood to flow backward and pool in the lower legs. This backward flow is called reflux, and it creates sustained high pressure inside the veins. Over time, that pressure stretches the vein walls further, damages more valves, and creates a cycle that gets progressively worse. In some cases, a blood clot in a deep vein causes scarring and narrowing that blocks normal flow, producing the same result: too much pressure building up below the obstruction.
The Three Vein Systems Involved
Your legs have three interconnected vein networks, and disease can start in any of them. Superficial veins run just beneath the skin and are the ones you can see bulging as varicose veins. Deep veins sit inside the muscle compartments and carry the majority of blood back to the heart. Perforating veins connect the two systems.
When perforating vein valves fail, high-pressure blood from the deep system gets forced into the superficial veins, which aren’t built to handle it. The superficial veins dilate, their valve flaps can no longer meet in the middle, and reflux spreads outward. Deep vein damage, often a consequence of a prior blood clot, tends to cause more severe symptoms because it disrupts the main return pathway entirely.
Symptoms From Early to Advanced
Early vein disease often feels like tired, heavy legs at the end of the day. You might notice a tight sensation in your calves, itching along the lower legs, or mild swelling around your ankles that improves overnight. Leg cramps and restless legs, especially at night, are also common early signs. Pain when walking that eases when you rest is another hallmark, since walking activates the calf muscle pump and temporarily improves circulation.
As the condition progresses, symptoms become harder to ignore:
- Visible varicose veins (3 mm or larger in diameter), often ropy and raised
- Persistent swelling that no longer resolves with rest
- Skin discoloration, typically brown patches near the ankles caused by iron deposits from red blood cells leaking into surrounding tissue
- Skin thickening and hardening of the lower leg, sometimes with eczema-like irritation
- Venous ulcers, open wounds that develop near the ankle and can be extremely slow to heal
Stages of Vein Disease
Doctors classify vein disease on a seven-point scale. Stage C0 means no visible signs. C1 involves spider veins or small reticular veins. C2 is the varicose vein stage, where veins measure 3 mm or more across. C3 adds persistent swelling. C4 is where skin damage begins, split into pigmentation and eczema (C4a) and more serious skin hardening or white scarring (C4b). C5 describes a venous ulcer that has healed, and C6 means an active, open ulcer.
Most people who seek treatment fall into C2 or C3. The progression isn’t inevitable at every stage, but without intervention, the trend moves in one direction. In one study, 84% of treated patients improved by at least one clinical stage after a year.
Who Gets Vein Disease
Varicose veins alone affect between 5 and 30% of adults, depending on the population studied. The Edinburgh Vein Study, which used ultrasound on over 1,500 people, found venous insufficiency in about 9% of men and 7% of women, rising sharply with age to 21% of men and 12% of women over 50. While vein disease has traditionally been considered more common in women, recent evidence suggests men may actually be affected at equal or higher rates but are less likely to seek care.
The strongest risk factors are age, obesity, prolonged standing or sitting, pregnancy, and a family history of vein problems. Obesity deserves special attention: women with a BMI of 40 or higher have more than three times the rate of blood clot complications compared to those with a BMI of 30 to 35. Each pregnancy adds cumulative stress to the venous system because of increased blood volume and hormonal changes that relax vein walls. People who stand for long hours at work, such as nurses, teachers, and retail workers, face higher risk because gravity works against venous return whenever the calf pump isn’t active.
How Vein Disease Is Diagnosed
The primary diagnostic tool is a duplex ultrasound, a painless, noninvasive scan that shows both the structure of your veins and the direction of blood flow in real time. The technician applies gentle pressure or uses a cuff to see if blood flows backward when released. A reflux time longer than half a second in superficial veins, or longer than one second in deep veins, confirms significant valve failure. The test takes about 30 to 45 minutes and is usually done while you’re standing, since gravity needs to be working against the valves for the problem to show up.
Treatment Options
Compression stockings are the first-line treatment for all stages of vein disease. They work by applying graduated pressure, tightest at the ankle and loosening toward the knee, to help push blood upward. For symptom relief in early stages, stockings in the 15 to 20 mmHg range provide measurable improvement in pain and swelling. For more advanced disease or healed ulcers, higher compression in the 30 to 40 mmHg range is more effective at preventing recurrence. In fact, recurrence rates for venous ulcers tell a striking story: 96% of patients in low-compression stockings saw their ulcers return within 10 years, compared to just 25% of those using high-compression multilayer systems.
When compression alone isn’t enough, minimally invasive procedures can close or remove the damaged veins. Endovenous laser ablation uses heat delivered through a thin fiber to seal the vein shut. Foam sclerotherapy injects a chemical that collapses the vein wall. Both are performed in an office setting with local anesthesia, and most people return to normal activity within a day or two. After one year, laser ablation and surgical stripping show similar success rates around 88%, while foam sclerotherapy is effective in about 72% of cases. All three approaches lead to significant improvement in quality of life.
The treated veins are permanently closed or removed, and blood reroutes through healthier veins. Because the underlying tendency toward valve weakness remains, new varicose veins can develop over time, and some people need additional treatment years later.
What Happens Without Treatment
Untreated vein disease doesn’t just stay the same. The sustained high pressure damages the smallest blood vessels in the skin, leading to a cascade of changes: chronic swelling, darkening skin, thickening tissue, and eventually ulceration. Venous ulcers are notoriously difficult to heal and have high recurrence rates. The same pooling of slow-moving blood also creates conditions that favor clot formation, linking chronic venous insufficiency to a higher probability of deep vein thrombosis.
Lifestyle changes can slow progression even if you’re not ready for medical treatment. Regular walking activates the calf muscle pump. Elevating your legs above heart level for 15 to 20 minutes several times a day helps drain pooled blood. Maintaining a healthy weight reduces the pressure load on your venous system. Avoiding long periods of standing or sitting without movement keeps blood circulating. These measures won’t reverse existing valve damage, but they meaningfully reduce symptoms and can delay the march toward more advanced stages.