DVT: BIG killer
March is DVT Awareness Month.
Deep-vein thrombosis (DVT) is a common but serious medical condition that occurs in approximately two million Americans each year. DVT occurs when a thrombus (blood clot) forms in one of the large veins, usually in the lower limbs, leading to either partially or completely blocked circulation. The condition may result in health complications, such as a pulmonary embolism (PE) and even death if not diagnosed and treated effectively.
According to the American Heart Association, DVT affects up to two million Americans annually. Of those who develop PE, up to 200,000 will die each year-more than from breast cancer and AIDS combined. Yet, a national survey sponsored by the American Public Health Association found that most Americans (74 percent) are unaware of DVT.
Symptoms of DVT may include pain, swelling, tenderness, discoloration or redness of the affected area, and skin that is warm to the touch. However, as many as half of all DVT episodes produce minimal symptoms or are completely “silent.”
Because a number of other conditions – including muscle strains, skin infections, and phlebitis (inflammation of veins) – display symptoms similar to those of DVT, the condition may be difficult to diagnose without specific tests.
DVT was first linked to air travel in 1954 and recent studies have suggested that it can increase the risk of a fatal clot by up to four times. Until today it was widely thought that it was brought on by long periods spent in cramped seats without exercise.
In an interesting new study, researchers discovered that DVT on flights may be caused by poor air quality.
Research from the World Health Organisation (WHO) published in The Lancet suggests "the low pressure and low oxygen environment during air travel may contribute to the development of DVT in some susceptible individuals".
The WHO research involved 71 health volunteers who were tested for possible blood clotting before, during and after an eight-hour flight.
The same volunteers were tested during eight hours of sitting in a cinema and during eight hours of regular activities.
The authors found increased concentrations in markers during flight compared to the other two situations. "Activation of coagulation (clotting) occurs in some individuals after an 8-hour flight, indicating an additional mechanism to immobilization underlying air travel related to thrombosis."
The study also found that that 43 per cent of those with the factor V gene (a clotting factor) who were taking the Pill were showing early signs of possible clotting. This compared with 9 per cent of those with one risk factor and 10 per cent of those with no risk factors.
What to do now?
The authors advised air travelers to avoid taking sedatives or drinking too much alcohol during flights to reduce the risk of DVT. Compressive stockings that improve blood flow could also help.
Complete the Risk Assessment Tool to determine your risk for a dangerous DVT.
David Bloom's DVT