Migraine and blood clots in veins (thrombosis)

Migraine with aura is known to be associated with an increased risk of diseases of arteries, such as strokes, heart attacks and diseases of peripheral blood vessels. This risk is further increased by estrogen-containing contraceptives.

A new study by Taiwanese neurologists suggests that migraine with aura also carries a higher risk of blood clots forming in the veins, so called venous thrombosis or deep vein thrombosis (DVT). Venous thrombosis is more likely to occur in obese, people with cancer, smokers, women on birth control pills, and those who are bedridden or sit for a long time, like on a long airplane ride. According to this new study, having migraines with aura increases the risk of this condition by two and half times.

DVT, which most commonly occurs in a deep vein in a leg, can completely resolve on its own without any residual effects. However, it can also cause long-term swelling and poor circulation in the leg and in about 10% of cases, a piece of the blood clot can break off and be carried into the lung. This is called pulmonary embolus and it is fatal in 10% of patients. DVT requires urgent treatment with blood thinners, which can prevent pulmonary emboli.

So, it is important to recognize symptoms of DVT. These include swelling in a leg or an arm, pain or tenderness in the leg when standing or walking, warmth in the area that is swollen or hurts, redness of the skin, and visible enlargement of the veins in the leg or arm.

Symptoms of pulmonary embolus are sudden shortness of breath or cough, rapid breathing, chest pain, back pain, profuse sweating, lightheadedness, and passing out.

Because blood clot can damage valves inside the vein some people develop a post-thrombotic syndrome, which can consist of pain, persistent swelling, darkened skin color, skin sores and varicose veins (enlarged and tortuous veins that sometimes can be seen under the skin).

To reduce the risk of both arterial and venous complications one needs to stop smoking, exercise regularly, maintain normal weight, blood pressure and blood sugar, avoid estrogen-containing contraceptives and hormone replacement therapy, and avoid sitting for prolonged periods of time. Obviously, these measures apply to everyone, but they are particularly crucial for those with migraine with aura.