Arterial Thrombosis in Patients with Primary Immune Thrombocytopenia: A Nationwide Study

Primary immune thrombocytopenia (pITP) is an acquired bleeding disorder related with mainly decreased number of platelets due to destruction or impaired production of platelets. Clinical presentation of pITP can be multifaceted, and thrombotic events may rarely manifest. Thrombosis can develop with treatment or during the untreated period. The primary objective of the study was to examine the frequency of arterial thromboembolism (ATE) in patients with pITP. We also aimed to evaluate the risk factors in these patients and the effect of ITP treatments on ATE. The study was designed as a retrospective, multicenter, conducted under the Turkish Society of Hematology's Scientific Subcommittee on Hemostasis-Thrombosis. Patients over the age of 18 with pITP and who subsequently developed ATE while undergoing follow-up for pITP were evaluated. A total of 2,178 patients with pITP were screened, and 37 patients (1.7%) were observed to have ATE. The mean age was 62 years. Fifteen (40.5%) of the patients who developed ATE were not receiving pITP treatment at the time of thromboembolism. The patients receiving pITP treatment at the time of ATE, 9 patients (24.3%) were receiving eltrombopag and 10 patients (27%) were receiving corticosteroids. Compared to patients who did not develop ATE, multivariate analysis revealed that presence of hypertension, comorbidity, and the history of venous thromboembolism statistically significantly increased the risk of developing ATE (p: 0.008, 0.018, 0.038). It should be noted that the risk of ATE may increase in pITP patients both during and without treatment. It is important to inquire thoroughly about the presence of comorbidities, atherosclerotic risk factors, hypertension and history of thrombosis in patients at the initiation of treatment. Correctable risk factors should be addressed to minimize the number of risk factors present. The treatment of pITP shall be individualized and incorporate age-related disorders.