Risk Factors for Thromboembolism (TE) in Multiple Myeloma (MM) Patients (pts) Treated with Immunomodulatory Agents (IMiDs) Plus Dexamethasone (dex)

• Published in: Blood 2018-11, Vol.132 (Supplement 1), p.4814-4814
• Main Authors: Patel, Jai N, Jagosky, Megan Helena, Robinson, Myra M, Slaughter, Daniel, Arnall, Justin, Matusz-Fisher, Ashley, Bhutani, Manisha, Voorhees, Peter M., Usmani, Saad Z.
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2018-99-118283

Introduction: MM pts have one of the highest risks of TE among cancer pts. Use of IMiDs plus dex further increases this risk. Guidelines recommend thromboprophylaxis based on risk assessment; however, limited large-scale studies have attempted to validate previous and identify new patient-specific risk factors associated with TE in MM pts. Methods: We conducted a retrospective review of 834 new or relapsed MM pts treated at Levine Cancer Institute between January 2012 to December 2017. Eligibility criteria for final analysis included age ≥ 18 years, diagnosis of MM, and treatment with thalidomide, lenalidomide or pomalidomide plus dex. Incidence of TE, including pulmonary embolism, deep vein thrombosis, and myocardial or cerebrovascular infarction, was documented up to 6 months after start of IMiD therapy. Presence of anticoagulation (AC)/antiplatelet therapy and type (aspirin [ASA], clopidogrel, low molecular weight heparin, warfarin, rivaroxaban, apixaban, dabigatran) were documented for each pt. Univariate and multivariable logistic regression models were used to investigate the association between TE incidence and race, gender, age, BMI, cytogenetic risk level, disease burden (bone marrow plasma cell percentage), AC/antiplatelet use, history of TE, and presence or history of comorbidities, including diabetes, kidney disease, atrial fibrillation, coronary artery disease, heart disease, and clotting disorder. Results: Of 834 pts, 373 were eligible for final analysis; 311 were excluded for not receiving an IMiD, 109 did not receive dex concomitantly with IMiD, and the remainder had other plasma cell dyscrasias and/or insufficient records. Mean age at IMiD start was 65.8 years; 48.5% were female, 58.2% Caucasian, and 35.4% African American. Most pts (96.5%) received lenalidomide as initial IMiD and 24% had high-risk disease. Half of all pts had ≥ 1 comorbidity, 8% had a history of TE, 73.7% received ASA prophylaxis, 14.2% received a stronger AC, and 12.1% did not receive thromboprophylaxis. The overall TE incidence was 31/373 (8.3%), of which 25 (6.7%) were venous and 6 (1.6%) were arterial. Of these, 30 received thromboprophylaxis. TE incidence among patients receiving ASA was 25/275 (21 venous, 4 arterial) and incidence among patients receiving stronger ACs was 5/53 (4 venous, 1 arterial). The univariate and multivariable results are summarized in the table. In univariate analysis, presence of ≥ 1 comorbidity (OR 2.98, 95% CI 1.30-6.84; p=0.01) and histo