Bleeding Patterns in Type I VWD in Effect of VWF Levels: An Individual Participant Data Meta-Analysis of Three Cohorts

Type I von Willebrand disease (VWD) is the most frequent bleeding disorder, with a prevalence of 10-50 cases per 10,000 persons. VWD usually shows an autosomal dominant inheritance pattern, at least in families having VWF:Ag levels below 30 IU/dL. There is considerable uncertainty whether patients having only mildly reduced VWF levels (in the range 30-50 IU/dL) should be diagnosed as having VWD or if they should be considered as a separate clinical entity, broadly referred to as "reduced VWF patients." We hypothesize that these patients may have a clinically distinct bleeding pattern, in terms of presenting symptoms at diagnosis, bleeding severity, and possibly even clinical.We pooled data from three cohorts of patients. The MCMDM-1 VWD Study is a multicenter survey on type 1 VWD that recruited 154 type 1 VWD families from nine European countries. The Kingston cohort recruited consecutive patients with type 1 VWD diagnosed in Kingston, Canada and includes patients screened because of bleeding symptoms or family history of VWD over a 10 year period. The Zimmerman Program for the Molecular and Clinical Biology of VWD is a multicenter study that enrolled VWD patients mostly from US clinical centres, primarily carrying a diagnosis of type 1 VWD (315 families) but also including type 2 and type 3 subjects. For the present study, only patients with a confirmed diagnosis of type 1 VWD were retained. From the three cohorts, demographic, laboratory and clinical data were abstracted, i...
Source: Blood - Category: Hematology Authors: Tags: 322. Disorders of Coagulation or Fibrinolysis: Poster I Source Type: research