A report published online on September 10, 2007 in Circulation: Journal of the American Heart Association concluded that supplementing with vitamin E may reduce the risk of venous thromboembolism (VTE) among women. The condition occurs when blood clots form in the veins, which subsequently dislodge and travel through the bloodstream, and is life-threatening when the clots block circulation to the brain, heart or lungs. The current treatment is warfarin, a blood thinner which often has side effects.
In the current study, which was funded by the National Institutes of Health, Robert J. Glynn, PhD, ScD and his Harvard colleagues reviewed data from The Womenís Health Study, a randomized trial of 39,876 women who received 600 international units vitamin E every other day or a placebo for a ten year average period. Over the course of the study, 213 women who received vitamin E and 269 in the placebo group developed venous thromboembolism, indicating a 21 percent risk reduction associated with the vitamin compared with the placebo. For unprovoked venous thromboembolism, which is not caused by trauma, surgery, or cancer, vitamin E supplementation was associated with a 27 percent reduction in risk.
In a subgroup of 1,131 women who reported a history of venous thromboembolism prior to the trial, the condition was reduced by 44 percent in the vitamin E group, while among those with no history, the risk was 18 percent lower. And, among women found to have one of two genetic mutations associated with increased VTE risk (factor V Leiden and the G20210A prothrombin mutation), vitamin E supplementation was associated with a 49 percent reduction in the risk of occurrence compared with women in this category who received the placebo.
"Women who had an event before the study had a much higher event rate during the study, and the vitamin E worked a little better in that population than in the general population, when it came to reducing VTE risk," noted Dr Glynn, who is an associate professor of medicine at Harvard Medical School. "It seems that women who would particularly be interested in a preventive agent actually seemed to have a larger benefit."
"While warfarin is quite effective for preventing VTE, we were looking for a preventive strategy that might be simple, with low side effects for this common disease," he stated. "In this study, VTE occurred more often than heart attacks and almost as often as stroke. People donít realize how common it is."
Related Health Concern: Blood Clot Prevention
Thrombi (blood clots) are a leading cause of death and disability in the United States (American Heart Association 2004). Blood clots are responsible for a grim litany of health problems, including stroke, heart attack, pulmonary embolism, and complications of cancer. Because of this intense danger, conventional physicians prescribe a number of powerful drugs to prevent blood clots. But these drugs have dangers of their own; if their use is not closely monitored, they may cause serious bleeding and even death.
If this happens in an artery, any tissue that is downstream from the blockage will quickly become starved of oxygen and start to die. If it occurs in the coronary arteries that feed the heart, a heart attack may result. If this takes place in the arteries that feed the brain, an ischemic stroke or transient ischemic attack (TIA, also known as a ministroke) may result. Atrial emboli (blood clots that form in the heart chambers) can travel to the lungs, causing a potentially fatal blockage called a pulmonary embolism. In other instances, the clots can travel to the brain, causing a stroke.
Blood clots can also occur in the veins, which transport oxygen-poor blood from the body back to the heart. Blood clots may be caused by sluggish blood flow due to disease, injury to the vein, or even long periods of immobility. Sometimes these venous blood clots pose relatively little threat beyond cosmetic injury, such as in the case of varicose veins. However, if a blood clot forms in the deep veins of the legs (called deep vein thrombosis), there is a significant risk the clot will break off and travel to the lungs.
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