Assessing the Impact of the 2021 VWD Guidelines on the Diagnosis/Management of Low VWF Patients

Introduction The 2021 ASH/ISTH/NHF/WFH VWD diagnosis guidelines recommend Type 1 VWD diagnoses for patients with (a) VWF <0.30 IU/mL or (b) ‘Low VWF’ 0.30–0.50 IU/mL with the presence of abnormal bleeding. This recommendation recategorizes ‘Low VWF’ patients with abnormal bleeding into Type 1 VWD. Aim To assess the impact of the 2021 VWD guidelines on the diagnosis and management of ‘Low VWF’ patients. Methods A single centre retrospective study was conducted to review all patients presenting for VWD evaluation between January 2000 to September 2024, analyzing for clinical features, ISTH‐BAT scores, VWF/FVIII levels, and management of bleeding. 149 patients, totalling 305 clinical encounters, were included in the study. Results Seventy five percent of patient encounters had a change in diagnosis from ‘Low VWF’ to Type 1 VWD after applying the 2021 VWD diagnosis guidelines. The use of VWF therapy (statistically significant, p = 0.04) and antifibrinolytics (not statistically significant, p = 0.52) increased in the post‐guidelines period compared to pre‐guidelines period. More than half saw increasing VWF levels with age, emphasizing the need to periodically re‐evaluate/re‐test patients with ‘Low VWF’. Conclusion Applying the 2021 VWD guidelines leads to improved diagnosis and management of symptomatic patients with ‘Low VWF’ as they are now classified as Type 1 VWD and receive optimal care with increased use of haemostatic therapy.