By: Bianca F. Marcolino, Ph.D. in Biological Sciences from UCLA
Publication Date: Monday, 7/14/2014
Blood coagulation is an important defense mechanism the human body employs to prevent excessive blood loss during injury. If unregulated, however, blood clotting can become a serious health risk. Conditions known as hypercoagulable states promote abnormal blood clot formation that can partially or fully obstruct blood flow in blood vessels. Hypercoagulable states are harmful, because they prevent oxygen carried by the blood from reaching the body’s organs. Oxygen deprivation leads to cell death and massive tissue loss . Because of the health complications related to hypercoagulable states, it is important to understand their underlying causes. This article will focus on the hypercoagulable state resulting from Factor V Leiden.
Hypercoagulable states can be conferred genetically – they can also be acquired through surgery, trauma, and medical conditions such as cancer and obesity – with the most pervasive genetic risk attributed to the presence of Factor V Leiden . Factor V Leiden refers to a mutation in coagulation factor V that prevents it from being silenced by coagulation inhibitor protein C . The prolonged activity of coagulation factor V results in increased blood clotting episodes. People who have inherited one copy of mutated factor V have a seven-fold risk of blood clotting events, while those who have inherited both copies of the mutated gene have a 50 to100-fold risk . The incidence of Factor V Leiden has also been shown to differ among races. In the United States, Factor V Leiden is highest among Caucasians (5.2%), and Hispanics (2.2%). Taken together, the data shows a strong genetic and racial component to having Factor V Leiden.
There are available treatment options for Factor V Leiden hypercoagulable states. Heparin and Warfarin are commonly given to alleviate the blood clotting. Both are anticoagulants, but there are differences between when and how they are taken. Patients are initially given a combination of Heparin plus Warfarin, followed by Warfarin exclusively . Heparin is administered initially, via intravenous injection once daily, because it elicits a faster patient response compared to Warfarin. Heparin is phased out when symptoms improve, because Warfarin alone is equally efficacious and of its less invasive mode of delivery. Warfarin is taken orally and treatment can last 3 to 6 months from initial administration . Rivaroxaban is a new oral drug that can be taken alone to treat blood clotting, thereby eliminating the need for initial combination therapy. The limitations of Rivaroxaban are its high cost in the U.S. and the lack of a reversal agent in cases of excessive patient bleeding . It is crucial to point out that the patient’s physician must continually monitor treatment dosage and duration, as well as the possibility of pregnancy in female patients, to avoid dangerous complications with anticoagulation therapy.
Before the advent of anticoagulation therapy, abnormal blood clotting claimed lives in 30% of cases . Current therapies coupled with frequeny INR testing and careful observation by one’s physician support successful disease management.
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