Among classic myeloproliferative neoplasms, essential thrombocythemia is associated with the greatest risk of venous thromboembolism during COVID-19
Tiziano Barbui, Valerio De Stefano, Alberto Álvarez‐Larrán, Alessandra Iurlo, Arianna Masciulli, Alessandra Carobbio, Arianna Ghirardi, Alberto Ferrari, Valeria Cancelli, Elena Maria Elli, Marcio Andrade‐Campos, Mercedes Gasior Kabat, J.‐J. Kiladjian, Francesca Palandri, Giulia Benevolo, Valentín García‐Gutiérrez, María Laura Fox, María Ángeles Foncillas, Carmen Morcillo, Elisa Rumi, Santiago Osorio, Petros Papadopoulos, Massimiliano Bonifacio, Keina Quiroz Cervantes, Miguel Sagüés Serrano, Gonzalo Carreño‐Tarragona, Marta Sobas, Francesca Lunghi, Andrea Patriarca, Begoña Navas Elorza, Anna Angona, Elena Magro Mazo, Steffen Koschmieder, Giuseppe Carli, Beatriz Cuevas, Juan Carlos Hernández‐Boluda, Emma Lopez Abadia, Blanca Xicoy Cirici, Paola Guglielmelli, Marta Garrote, Daniele Cattaneo, Rosa Daffini, Fabrizio Cavalca, Beatríz Bellosillo, Lina Benajiba, Natalia Curto‐García, Marta Bellini, Silvia Betti, Claire Harrison, Alessandro Rambaldi, Alessandro M. Vannucchi
Abstract
In a multicenter European retrospective study including 162 patients with COVID-19 occurring in essential thrombocythemia (ET, n = 48), polycythemia vera (PV, n = 42), myelofibrosis (MF, n = 56), and prefibrotic myelofibrosis (pre-PMF, n = 16), 15 major thromboses (3 arterial and 12 venous) were registered in 14 patients, of whom all, but one, were receiving LMW-heparin prophylaxis. After adjustment for the competing risk of death, the cumulative incidence of arterial and venous thromboembolic events (VTE) reached 8.5% after 60 days follow-up. Of note, 8 of 12 VTE were seen in ET. Interestingly, at COVID-19 diagnosis, MPN patients had significantly lower platelet count (p < 0.0001) than in the pre-COVID last follow-up.This decline was remarkably higher in ET (-23.3%, p < 0.0001) than in PV (-16.4%, p = 0.1730) and was associated with higher mortality rate (p = 0.0010) for pneumonia. The effects of possible predictors of thrombosis, selected from those clinically relevant and statistically significant in univariate analysis, were examined in a multivariate model. Independent risk factors were transfer to ICU (SHR = 3.73, p = 0.029), neutrophil/lymphocyte ratio (SHR = 1.1, p = 0.001) and ET phenotype (SHR = 4.37, p = 0.006). The enhanced susceptibility to ET-associated VTE and the associated higher mortality for pneumonia may recognize a common biological plausibility and deserve to be delved to tailor new antithrombotic regimens including antiplatelet drugs.