Long Term Follow-up of 107 Patients with Essential Thrombocythemia: Role of Cardiovascular Events

BACKGROUND Essential Thrombocythemia (ET) is a Philadelphia-negative chronic myeloproliferative neoplasm characterized by haemorrhagic and thrombotic complications. Haemorrhagic events and arterial and venous thrombosis, including microcirculation transient occlusions, are the major causes of morbidity in ET patients. The control of these events represents the goal of standard therapeutic approaches.

MATERIALS AND METHODS We retrospectively analysed data about 107 ET patients who received diagnosis between January 1980 and June 2014. Median follow-up was 80 months,16 patients were lost during follow-up. The medium age at diagnosis was 60 years, with a prevalence of female (66 patients).We recorded adverse cardiovascular events at diagnosis and during follow-up, assessing whether cytoreductive ad antiplatelet therapy could reduce such events and improve quality of life. Finally, we evaluated the impact of additional cardiovascular risk factors.

OBJECTIVES to observe incidence and kind of thrombotic events in patients affected by ET at diagnosis and during follow-up.

RESULTS 30 patients (27.7%) had a history of thrombosis at diagnosis (8 transient cerebral ischemia, 7 myocardial infarction/unstable angina, among them 7 patients experienced a rethrombosis during follow-up. 16 patients (15%) developed a first thrombotic event, all patients were under cytoreductive treatment. 21 patients with a history of thrombosis had more than 60 years at diagnosis, 19 patients (63%) had at least one additional cardiovascular risk factor among arterial hypertension, dyslipidemia, diabetes, obesity, hyperuricemia and smoking. Median platelet count was 813000/mm³, leukocyte count greater was more than 10000/mm³ in half of patients. Evolution to acute leukemia/myelofibrosis occurred in 3 (2,7%) and 7 (6,5%) patients of total.

CONCLUSIONS The occurrence of thrombotic events even in patients with good hematologic response of disease and during antiplatelet and cytoreductive therapy, indicates the presence of a residual risk of thrombosis. This risk is not yet fully clarified by retrospective studies published until now. Prospective studies will be useful to evaluate the role and the importance of comorbidity in these patients with long-prognosis, in order to optimize therapy, reduce cardiovascular events and improve quality of life