What is the most common type of von Willebrand disease?

Von Willebrand disease (vWD) is a genetic disorder that leads to increased bleeding due to a deficiency or dysfunction of von Willebrand factor, which is crucial for platelet adhesion and clotting. The most common type of von Willebrand disease is Type 1, characterized by a partial deficiency of von Willebrand factor. Patients with Type 1 vWD typically have mild bleeding symptoms, which may include easy bruising and nosebleeds, but they usually have a normal or only slightly reduced level of von Willebrand factor.

Type 2 and Type 3 von Willebrand diseases are less common and involve more severe deficiencies or qualitative dysfunction of the von Willebrand factor. Type 2 is characterized by an abnormal form of the factor, leading to more significant bleeding problems. Type 3 is the most severe form, resulting in undetectable levels of von Willebrand factor and significantly increased bleeding risk.

Acquired von Willebrand disease is not a genetic disorder but occurs due to other medical conditions, such as autoimmune diseases or certain types of cancers. Understanding these differences helps clarify why Type 1 is the most prevalent form of this disorder, making it the correct answer in this context.