von Willebrand disease and aging: an evolving phenotype Y. V. SANDERS,* M. A. GIEZENAAR,* B. A. P. LAROS-VAN GORKOM,† K. MEIJER,‡ J. G. VAN DER BOM,§¶M. H. CNOSSEN,** M. R. NIJZIEL,††P. F. YPMA,‡‡K. FIJNVANDRAAT,§§

Summary. Background: Because the number of elderly vonWillebrand disease (VWD) patients is increasing, the path-ophysiology of aging in VWD has become increasinglyrelevant. Objectives: To assess age-related changes in vonWillebrand factor (VWF) and factor VIII (FVIII) levelsand to compare age-related differences in bleeding pheno-type between elderly VWD patients and those < 65 years.We also studied co-morbidity in elderly patients. Patients/Methods: We included VWD patients with VWF levels≤ 30 U dL 1 in the nationwide cross-sectional ‘Wille-brand in the Netherlands’ (WiN-) study. Patients reportedbleeding episodes and treatment of VWD in the year pre-ceding inclusion and during life. This was comparedbetween VWD patients older (n = 71) and younger (16–64 years, n = 593) than 65 years. In elderly patients, age-related changes in VWF and FVIII levels were studiedlongitudinally by including all historically measured levels.All medical records were examined for co-morbidity.Results: In elderly type 1 patients, a decade age increasewas associated with a 3.5 U dL