title: Prophylaxis in severe forms of von Willebrand's disease: results from the von Willebrand Disease Prophylaxis Network (VWD PN).
abstract: The bleeding patterns of severe von Willebrand's disease (VWD) adversely affect quality of life, and may be life threatening. There is a presumed role for prophylaxis with VWF-containing concentrates, but data are scarce. The von Willebrand Disease Prophylaxis Network (VWD PN) was formed to investigate the role of prophylaxis in clinically severe VWD that is not responsive to other treatment(s).Using a retrospective design, the effect of prophylaxis was studied. Availability of records to document, or reliably assess, the type and frequency of bleeding episodes prior to, and after, the initiation of prophylaxis was required. Annualized bleeding rates were calculated for the period prior to prophylaxis, during prophylaxis and by primary bleeding indication defined as the site accounting for more than half of all bleeding symptoms. The Wilcoxon signed-rank test of differences in the medians was used. Sixty-one subjects from 20 centres in 10 countries were enrolled. Data for 59 were used in the analysis. The median age at onset of prophylaxis was 22.4 years. Type 3 VWD accounted for the largest number (N = 34, 57.6%). Differences in bleeding rates within individuals during compared with before prophylaxis were significant for the total group (P < 0.0001), and for those with primary bleeding indications of epistaxis (P = 0.0005), joint bleeding (P = 0.002) and GI bleeding (P = 0.001). The effect of prophylaxis was similar among those age < 18 years and those ≥ 18. One person developed an inhibitor during treatment. We conclude that prophylactic treatment of VWD is efficacious.
authors: Medical Sciences Institute, BloodCenter of Wisconsin, Milwaukee, WI, USA.
authors: T C
authors: TC
authors: Abshire
authors: A B
authors: AB
authors: Federici
authors: M T
authors: MT
authors: Alvárez
authors: J
authors: J
authors: Bowen
authors: M D
authors: MD
authors: Carcao
authors: J
authors: J
authors: Cox Gill
authors: N S
authors: NS
authors: Key
authors: P A
authors: PA
authors: Kouides
authors: K
authors: K
authors: Kurnik
authors: A E
authors: AE
authors: Lail
authors: F W G
authors: FW
authors: Leebeek
authors: M
authors: M
authors: Makris
authors: P M
authors: PM
authors: Mannucci
authors: R
authors: R
authors: Winikoff
authors: E
authors: E
authors: Berntorp
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003029:Coagulants / Q000627:therapeutic use*; D004334:Drug Administration Schedule; D005260:Female; D006395:Hemarthrosis / Q000209:etiology / Q000517:prevention & control; D006470:Hemorrhage / Q000209:etiology / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult; D014842:von Willebrand Diseases / Q000150:complications / Q000188:drug therapy*; D014841:von Willebrand Factor / Q000627:therapeutic use*
chemical_list: D003029:Coagulants; D014841:von Willebrand Factor