Thromb Haemost 2020; 120(02): 322-328
DOI: 10.1055/s-0039-3400303
Stroke, Systemic or Venous Thromboembolism
Georg Thieme Verlag KG Stuttgart · New York

Development of a Clinical Prediction Rule for Venous Thromboembolism in Patients with Acute Leukemia

Fatimah Al-Ani
1  Division of Hematology, Department of Medicine, Western University, London, Ontario, Canada
,
Yimin Pearl Wang
1  Division of Hematology, Department of Medicine, Western University, London, Ontario, Canada
,
1  Division of Hematology, Department of Medicine, Western University, London, Ontario, Canada
2  Department of Epidemiology and Biostatistics, Western University, London, Ontario, Canada
› Author Affiliations
Funding This study was funded by the Canadian Venous Thromboembolism Clinical Trials and Outcomes Research (CanVECTOR) Network which receives grant funding from the Canadian Institutes for Health Research (Grant/Award number “CDT 142654”). F.A.-A was supported by a fellowship from the CanVECTOR Network. A.L.-L. is an investigator of the CanVECTOR Network.
Further Information

Publication History

21 May 2019

26 September 2019

Publication Date:
01 January 2020 (online)

Abstract

Risk factors for venous thromboembolism in patients with solid tumors are well studied; however, studies in patients with acute leukemia are lacking. We conducted a retrospective cohort study of adult patients diagnosed with acute myeloid leukemia and acute lymphoblastic leukemia diagnosed between June 2006 and June 2017 at a tertiary care center in Canada. Potential predictors of venous thromboembolism were evaluated using logistic regression and a risk score was derived based on weighed variables and compared using survival analysis. Internal validation was conducted using nonparametric bootstrapping. A total of 501 leukemia patients (427 myeloid and 74 lymphoblastic) were included. Venous thromboembolism occurred in 77(15.3%) patients with 71 events occurring in the first year. A prediction score was derived and validated and it included: previous history of venous thromboembolism (3 points), lymphoblastic leukemia (2 points), and platelet count > 50 × 109/L at the time of diagnosis (1 point). The overall cumulative incidence of venous thromboembolism was 44% in the high-risk group (≥ 3 points) versus 10.5% in the low-risk group (0–2 points) and it was consistent at different follow-up periods (log-rank p < 0.001). We derived and internally validated a predictive score of venous thromboembolism risk in acute leukemia patients.