IM - ORIGINAL Role of blood cells dynamism on hemostatic complications in low-risk patients with essential thrombocythemia Andrea Piccin • Michael Steurer • Manfred Mitterer • Elisabeth Maria Blo ¨chl • Luigi Marcheselli • Irene Pusceddu • Alessandra Marabese • Irene Bertozzi • Daisy Corvetta • Maria Luigia Randi • Elena Elli • Enrico Maria Pogliani • Dino Veneri • Omar Perbellini • Mauro Krampera • Enrica Pacquola • Michele Gottardi • Mario Tiribelli • Anna Guella • Barbara Innella • Paolo Vivaldi • Ercole De Biasi • Rosaria Sancetta • Roberta Rocconi • Renato Bassan • Filippo Gherlinzoni • Giovanni Pizzolo • Gu ¨ nther Gastl • Sergio Cortelazzo Received: 1 November 2014 / Accepted: 30 December 2014 / Published online: 14 January 2015 Ó SIMI 2015 Abstract Patients with essential thrombocythemia (ET) aged less than 60 years, who have not suffered a previous vascular event (low-risk patients), may develop thrombotic or hemorrhagic events. So far, it has not been possible to identify useful markers capable of predicting which of these patients are more likely to develop an event and therefore who needs to be treated. In the present study, we analysed the relationship between vascular complications and longitudinal blood counts of 136 low-risk ET patients taken over a sustained period of time (blood cells dyna- mism). After a median follow-up of 60 months, 45 out of 136 patients (33 %) suffered 40 major thrombotic and 5 severe hemorrhagic complications. A total number of 5,781 blood counts were collected longitudinally. Thrombotic and hemorrhagic events were studied together (primary endpoint) but also separately (thrombotic alone = sec- ondary endpoint; hemorrhagic alone = tertiary endpoint). The primary endpoint showed no significant association between platelet and WBC count at diagnosis and risk of any event (platelet, p = 0.797; WBC, p = 0.178), while Hb at baseline did show an association (p = 0.024). In the dynamic analysis with Cox regression model, where the blood count values were studied by time of follow-up, we observed that the risk for Hb was 1.49 (95 % CI 1.13–1.97) for every increase of 1 g/dL, and that this risk then mar- ginally decreased during follow-up. WBC was associated with an increased risk at baseline for every increase of 1 9 10 9 /L (hazard ratio (HR) 1.07, 95 % CI 1.01–1.13, p = 0.034), the risk was stable during follow-up (HR 0.95, p = 0.187 at 60 months). Also, for each increment at baseline of 100 9 10 9 platelets/L, HR was increased by 1.08 (95 % CI 0.97–1.22, p = 0.159) and decreases during follow-up. In conclusion, this study is the first to evaluate This work represents part of the thesis of Dr. Elisabeth Maria Blo ¨chl, which has been presented and recently approved as a MD diploma thesis at the Department of Oncohaematology of Innsbruck Medicine University, Austria (Professor Gu ¨nther Gastl and Prof Michael Steurer). A. Piccin (&) Á I. Pusceddu Á A. Marabese Á D. Corvetta Á S. Cortelazzo Department of Haematology, San Maurizio Regional Hospital, Bolzano, South Tyrol, Italy e-mail: apiccin@gmail.com A. Piccin Á M. Steurer Á E. M. Blo ¨chl Á G. Gastl Division of Haematology & Oncology, University Hospital, Innsbruck, Austria M. Mitterer Oncohaematology Unit, Meran Hospital, Merano, South Tyrol, Italy L. Marcheselli Department of Diagnostic, Clinical and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy I. Bertozzi Á M. L. Randi Department of Internal Medicine, University of Medicine, Padua, Italy E. Elli Á E. M. Pogliani Department of Haematology, University of Milano Bicocca, Milan, Italy D. Veneri Á O. Perbellini Á M. Krampera Á G. Pizzolo Department of Medicine, Section of Hematology, University of Verona, Verona, Italy E. Pacquola Á M. Gottardi Á F. Gherlinzoni Department of Haematology, Ca ` Foncello Hospital, Treviso, Italy 123 Intern Emerg Med (2015) 10:451–460 DOI 10.1007/s11739-015-1186-8