In a study published this month in the journal Haemophilia, investigators describe bleeding incidence and treatment in patients with type 3 von Willebrand disease (VWD) enrolled in the Centers for Disease Control Universal Data Collection (UDC) study. Type 3 VWD is a rare bleeding disorder characterized by very low levels—less than 10% of normal--or the absence of the von Willebrand factor (VWF) protein. The disorder is also associated with a parallel decline of VWF functioning and factor VIII (FVIII) activity.
The data for this study came from 150 UDC-enrolled type 3 VWD patients. The lead author was Ara Metjian MD, Division of Hematology, Duke University School of Medicine, Durham, NC. Metjian is a former recipient of the National Hemophilia Foundation Clinical Fellowship Award, a Baxter Healthcare Corporation-funded program.
An analysis of the data confirmed that nearly all of the type 3 VWD patients (98%) experienced bleeding episodes and 92% received treatment, often with a factor product. Oral mucosal bleeding was the most commonly reported hemorrhage; in 54% of the cases it was the site of a patient’s first bleed. Muscle bleeds were experienced by 28% of the patients and 45% sustained joint bleeds. Intracranial bleeding, a serious and potentially life-threatening complication, occurred in 8% of patients.
“This study documents the strong bleeding phenotype in severe VWD and provides data to help target therapy, including prophylaxis, for patients most at risk of bleeding complications,” concluded study authors.
The UDC study, administered through the Hemophilia Treatment Center (HTC) Network, was first established in 1997 to monitor the safety of the blood supply in the United States. This surveillance tool is also used to track the incidence and consequence of joint complications in study subjects with bleeding disorders.
The study, “Bleeding Symptoms and Laboratory Correlation in Patients with Severe von Willebrand Disease,” was published in the July 2009 issue of Haemophilia.
The work for this study was supported by the NHF-Baxter Fellowship Award and the Duke-UNC Clinical Hematology Research Career Development Program from the National Institutes of Health, and by Cooperative Agreement from the Centers for Disease Control and Prevention.