von Willebrand Disease
The most common type of bleeding disorder is called von Willebrand Disease (VWD). People with this condition have a problem with a protein in their blood called von Willebrand factor. When a blood vessel is injured and bleeding occurs, this protein helps cells in the blood form a clot. People with VWD do not have enough of this protein or they have the protein but it does not work correctly. The result is their blood takes longer to clot and for bleeding to stop.
VWD is generally less severe than other bleeding disorders. For most people with VWD, the disorder causes little or no disruption to their lives except when there is a serious injury or need for surgery. However, with all forms of VWD, there can be bleeding problems.
It is estimated that up to 1% of the world’s population suffers from VWD, but because many people have only very mild symptoms, only a small number of them know they have it. Research has shown that as many as 9 out of 10 people with VWD have not been diagnosed.
Types of VWD
There are three main types of VWD. Within each type, the disorder can be mild, moderate or severe. Bleeding symptoms can be quite variable within each type depending on the level of von Willebrand Factor (VWF). It is important to know which type of VWD a person has since treatment is different for each type.
Type 1 VWD is the most common form. People with Type 1 VWD have lower than normal levels of VWF. Symptoms are usually very mild. It is possible, however, for someone with Type 1 VWD to have serious, life-threatening, bleeding.
Type 2 VWD involves a defect in the VWF structure. The VWF protein does not work properly which causes lower than normal VWF activity. Symptoms are usually moderate.
Type 3 VWD is usually the most serious. People with Type 3 VWD have very little or no VWF. Symptoms are more severe. People with Type 3 VWD can have bleeding into muscles and joints.
Up to 1% of the world’s population suffers from von Willebrand Disease.