Development and validation of an International Prognostic Score of thrombosis in World Health Organization–essential thrombocythemia (IPSET-thrombosis)
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Open Access
- 20 December 2012
- journal article
- research article
- Published by American Society of Hematology in Blood
- Vol. 120 (26), 5128-5133
- https://doi.org/10.1182/blood-2012-07-444067
Abstract
Accurate prediction of thrombosis in essential thrombocythemia (ET) provides the platform for prospective studies exploring preventive measures. Current risk stratification for thrombosis in ET is 2-tiered and considers low- and high-risk categories based on the respective absence or presence of either age > 60 years or history of thrombosis. In an international study of 891 patients with World Health Organization (WHO)–defined ET, we identified additional independent risk factors including cardiovascular risk factors and JAK2V617F. Accordingly, we assigned risk scores based on multivariable analysis–derived hazard ratios (HRs) to age > 60 years (HR = 1.5; 1 point), thrombosis history (HR = 1.9; 2 points), cardiovascular risk factors (HR = 1.6; 1 point), and JAK2V617F (HR = 2.0; 2 points) and subsequently devised a 3-tiered prognostic model (low-risk = < 2 points; intermediate-risk = 2 points; and high-risk = > 2 points) using a training set of 535 patients and validated the results in the remaining cohort (n = 356; internal validation set) and in an external validation set (n = 329). Considering all 3 cohorts (n = 1220), the 3-tiered new prognostic model (low-risk n = 474 vs intermediate-risk n = 471 vs high-risk n = 275), with a respective thrombosis risk of 1.03% of patients/y versus 2.35% of patients/y versus 3.56% of patients/y, outperformed the 2-tiered (low-risk 0.95% of patients/y vs high-risk 2.86% of patients/y) conventional risk stratification in predicting future vascular events.Keywords
This publication has 26 references indexed in Scilit:
- Incidence and risk factors for bleeding in 1104 patients with essential thrombocythemia or prefibrotic myelofibrosis diagnosed according to the 2008 WHO criteriaLeukemia, 2011
- Myeloproliferative Neoplasms: Molecular Pathophysiology, Essential Clinical Understanding, and Treatment StrategiesJournal of Clinical Oncology, 2011
- Guideline for investigation and management of adults and children presenting with a thrombocytosisBritish Journal of Haematology, 2010
- Perspectives on thrombosis in essential thrombocythemia and polycythemia vera: is leukocytosis a causative factor?Blood, 2009
- Evidence and expertise in the management of polycythemia vera and essential thrombocythemiaLeukemia, 2008
- Leukocytosis is a risk factor for thrombosis in essential thrombocythemia: interaction with treatment, standard risk factors, and Jak2 mutation statusBlood, 2006
- The presence of the JAK2 V617F mutation is associated with a higher haemoglobin and increased risk of thrombosis in essential thrombocythaemiaBritish Journal of Haematology, 2005
- A Gain-of-Function Mutation ofJAK2in Myeloproliferative DisordersThe New England Journal of Medicine, 2005
- A unique clonal JAK2 mutation leading to constitutive signalling causes polycythaemia veraNature, 2005
- Overall C as a measure of discrimination in survival analysis: model specific population value and confidence interval estimationStatistics in Medicine, 2004