Abstract Number: PB0831
Meeting: ISTH 2021 Congress
Theme: Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies » Acquired Thrombocytopenias
Background: Primary immune thrombocytopenia (ITP) is an inherited autoimmune disorder characterised by peripheral platelet destruction and abnormally low platelet production.
Although the typical symptoms of this disease are bleeding events, a thrombophilic disorder has been described, with a higher risk of thrombosis than in the general population. This higher incidence has been associated with cardiovascular risk factors, such as arterial hypertension (HT), diabetes mellitus (DM), dyslipidemia (DL), smoking, advanced age and a previous history of thrombosis.
Aims: To analyze and evaluate the thrombotic events in patients with ITP in our center.
Methods: Observational, retrospective, single-center study in adult patients older than 18 years diagnosed with ITP.
Arterial thrombotic events were defined as stroke and myocardial infarction (MI).
Venous thrombotic events were considered pulmonary embolism (PE) and deep vein thrombosis (DVT).
Results: A total of 75 patients have been recruited and 11 thrombotic events were described highlighting that 5 thrombotic events occurred with a platelet count lower than 50 x109/L. Most arterial thrombotic events were in therapeutic abstinence (80%), however all patients with venous thrombosis events were on TPO analogs treatment (table 1).
In our series, the most important risk factor for presenting a thromboembolic event was the previous history of thrombosis, achieving statistical significance both the previous history of arterial thrombosis (p=0.006) and venous (p=0.007).
However, we did not find significant differences in other cardiovascular risk factors, possibly due to the limited sample size.
| Patients with thrombotic events n=8/75 (10.7%) |
Thrombotic events n=11 |
Platelets counts x109/L |
Treatment |
Esplenectomy |
Previous thrombosis |
||||
| Art | Ven | Ev 1 | Ev 2 | Ev 1 | Ev 2 | Art | Ven | ||
| Patient 1 | Yes | 74 | No | No | No | No | |||
| Patient 2 | Yes | 33 | Rom | No | Yes | Yes | |||
| Patient 3 | Yes | 45 | No | No | No | No | |||
| Patient 4 | Yes/Yes | 6 | 307 | Rom | Rom | No | No | No | |
| Patient 5 | Yes/Yes | 365 | 365 | Rom | Rom | No | Yes | Yes | |
| Patient 6 | Yes | 40 | No | Yes | Yes | No | |||
| Patient 7 | Yes/Yes | 49 | 53 | Elt | Elt | No | Yes | Yes | |
| Patient 8 | Yes | 429 | No | Yes | No | No | |||
Resume of the thrombotic events. Art: Arterial thrombosis; Elt: Eltrombopag; Ev1: First thrombosis; Ev2: Second thrombosis; Rom: Romiplostim; Ven: Venous thrombosis.
Conclusions: – Our results show a high prevalence of thrombosis in ITP patients, even despite presenting low platelet counts.
– The ratio of arterial and venous thrombosis was the same, however the use of TPO analogues was more associated with venous than arterial thrombosis.
– In our series, the greatest risk factor for suffering a thromboembolic event were having a previous history of thrombosis, despite being on antiplatelet or anticoagulant treatment.
To cite this abstract in AMA style:
Doblas-Marquez A, Lopez-Jaime F-, Martin-Tellez S, Sanchez-Bazan I, Muñoz-Perez M-. Prevalence of Thrombotic Events and Risk Factors in Patients with Primary Immune Thrombocytopenia [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/prevalence-of-thrombotic-events-and-risk-factors-in-patients-with-primary-immune-thrombocytopenia/. Accessed November 29, 2023.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/prevalence-of-thrombotic-events-and-risk-factors-in-patients-with-primary-immune-thrombocytopenia/