Among classic myeloproliferative neoplasms, essential thrombocythemia is associated with the greatest risk of venous thromboembolism during COVID-19

A retrospective study conducted in Europe of MPN patients with COVID-19 found that venous thromboembolism was seen in more patients with essential thrombocythemia (ET; 8 of 12) than those with other MPNs. In addition, patients had significantly lower platelet count (p < 0.0001) upon COVID-19 diagnosis than in their last follow-up prior to diagnosis, and the decline was higher for ET patients (−23.3%, p < 0.0001) than among those with polycythemia vera (−16.4%, p = 0.1730).