Abstract Number: PB1578
Meeting: ISTH 2020 Congress
Theme: Platelet Disorders and von Willebrand Disease » VWF and von Willebrand Factor Disorders - Clinical Conditions
Background: Increasing levels of von Willebrand Factor (VWF) and factor VIII (FVIII:C) were associated with age in patients affected by VWD type 1.
Aims: To evaluate the increase of FVIII:C and VWF with age in a large group of patients affected by VWD, in whom levels were repeatedly measured.
Methods: Clinical charts from all patients evaluated at the A. Bianchi Bonomi Hemophilia and Thrombosis Center between 1970 and 2018 were reviewed and data on VWF, FVIII:C, cancer, diabetes, hypertension collected. VWF activity was measured with 4 different assays depending on the date of the assay (VWF:Rco, measured by aggregometry, and subsequently with an automated coagulometer; VWF:Ab, and VWF:GpIbR). FVIII:C was measured by one-stage assay. The repeated measurements were evaluated by linear mixed effects models, adjusting for age at first measurement, sex, blood group (O or non-O), presence of comorbidities, and type of test for VWF activity.
Results: . In total 714 patients were included (23 excluded for missing data and 11 for VWD affecting only collagen binding or RIPA assays): 39 (5%) were affected by VWD type 3 or severe type 1, 314 (44%) by type 2, 293 (41%) by type 1 or 1 Vicenza, 68 by others (2N, not classified, type 3 carriers, type 2N carriers). Repeated measurements were available for 429 (60%) patients (172 type 1 and 211 type 2) for a total of 2844 tests. After adjustments, VWF activity and FVIII:C were positively associated with age (1.81 IU/dL and 2.86 IU/dL increase per decade respectively). Stratification on VWD type confirmed the increment of VWF activity in type 1 and of FVIII:C in type 1 and type 2 patients.
Conclusions: Our results indicate a mild increase of FVIII with age in patients with VWD. Only patients affected by type 1 VWD show a mild increase of VWF activity with age.
| All (N=714) | Type 1 (N=293) | Type 2 (N=314) | |
| Sex female, n (%) |
412 (58) | 185 (63) | 163 (52) |
| Blood group 0, n (%), missing |
296 (61), 229 | 153 (72), 81 | 109 (53), 107 |
| Age at first measurement, years median, IQ range), missing |
28 (13-42), 1 | 27 (16-39), 2 | 28 (11-46), 1 |
| VWF activity at 1st measurement, IU/dL median (IQ range), missing |
21 (6-40), 19 | 35 (20-44), 5 | 9 (3-22), 8 |
| FVIII:C at 1st measurement, IU/dL median (IQ range), missing |
53 (37-70), 19 | 58 (44-72), 5 | 49 (37-64), 10 |
| Time between first and last measurement, years median (IQ range), missing |
15 (6-24), 1 | 15 (7-21) | 15 (7-25), 1 |
| Number of repeated measurements, median (IQ range) |
3 (1-6) | 2 (1-5) | 3 (1-7) |
| Comorbidities (cancer, diabetes, high blood pressure) n (%), missing |
21 (5), 287 | 6 (3.5), 121 | 13 (6), 105 |
[Table 1. Clinical characteristics.]
| All patients (N=714) |
Type 1 (N=293) |
Type 2 (N=314) |
|
| VWF activity, IU/dL | |||
| Crude Beta coefficient per decade (95%CI) | 2.24 (1.63-2.84) |
2.67 (1.67-3.66) |
1.30 (0.64-1.97) |
| Adjusted# Beta coefficient per decade (95%CI) | 1.81 (0.33-3.28) |
5.13 (2.70-7.56) |
-0.040 (-2.13-1.33) |
| FVIII:C, IU/dL | |||
| Crude Beta coefficient per decade (95%CI) | 2.50 (1.68-3.33) |
2.14 (0.77-3.52) |
2.18 (1.16-3.20) |
| Adjusted# Beta coefficient per decade (95%CI) | 2.86 (1.66-4.06) |
2.94 (1.08-4.79) |
3.84 (2.25-5.44) |
| # adjusted for age at first measurement, sex, blood group, cancer, diabetes, hypertension (and test type for VWF). | |||
[Table 2. Increment of VWF:activity and FVIII:C with age.]
To cite this abstract in AMA style:
Biguzzi E, Siboni SM, Le Cessie S, Baronciani L, Rosendaal FR, van Hylckama Vlieg A, Peyvandi F. Increasing Levels of von Willebrand Factor (VWF) and Factor VIII (FVIII:C) with Age in Patients Affected by von Willebrand Disease (VWD) [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/increasing-levels-of-von-willebrand-factor-vwf-and-factor-viii-fviiic-with-age-in-patients-affected-by-von-willebrand-disease-vwd/. Accessed September 29, 2023.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/increasing-levels-of-von-willebrand-factor-vwf-and-factor-viii-fviiic-with-age-in-patients-affected-by-von-willebrand-disease-vwd/