ORIGINAL REPORT Real-life practices for preventing venous thromboembolism in multiple myeloma patients: a cohort study from the French health insurance database Aurore Palmaro 1,2,3 * , Marie-Eve Rougé-Bugat 2,4 , Martin Gauthier 5 , Fabien Despas 1,2,3 , Guillaume Moulis 1,2,3,6 and Maryse Lapeyre-Mestre 1,2,3 1 Medical and Clinical Pharmacology department, Toulouse University Hospital, Toulouse, France 2 UMR INSERM 1027, University of Toulouse, Toulouse, France 3 CIC 1436, Toulouse University Hospital, Toulouse, France 4 Academic Department of Family Medicine, Faculty of Medicine Toulouse, University of Toulouse, Toulouse, France 5 Department of Haematology, Toulouse University Hospital, Toulouse, France 6 Department of Internal Medicine, Toulouse University Hospital, Toulouse, France ABSTRACT Purpose The risk of venous thromboembolic event (VTE) in multiple myeloma is particularly increased. Current guidelines recommend systematic VTE prophylaxis with vitamin K antagonists (VKA) or low weight molecular heparin (LWMH) or unfractionated heparin (UFH) in high-risk patients, based on treatment received [e.g. use of IMiDs (thalidomide, lenalidomide and pomalidomide), alkylating agents or erythropoietin] and individual risk factors (e.g. history of VTE). The aim of this study was to describe strategy of VTE prophylaxis and prescribing of other antithrombotic agents during the first 6 months of multiple myeloma therapy, with stratification on IMiD-based regimens and drug and disease-related risk factors. Methods A retrospective cohort study of French beneficiaries from the health insurance database (SNIIRAM, Système National d’Information Inter-Régime de l’Assurance Maladie) was designed in the Midi-Pyrénées area (South West France). Patients starting a treatment for multiple myeloma in the period 2011–2014 were identified through hospital and chronic disease diagnoses. Results Among the 236 incident multiple myeloma patients, 56% male (n = 133), 67% >65 years (n = 159) and 47% (n = 110) patients received an IMiD-based regimen. In these patients, 63% (n = 69) were identified as high-risk patients with indication for low molecular weight heparin or equivalent, and 37% (n = 41) were identified as low-risk with aspirin recommended. Among the high-risk IMiDs patients, 43% (30/69) currently received a VTE prophylaxis after starting their first regimen: 70% LWMH (21/30), 40% VKA (12/30), 10% UFH (3/ 30) and 13% (4/30) other drugs (rivaroxaban and fondaparinux); 33% of the patients (23/69) received an antiplatelet drug only, and 23% (16/ 69) did not receive any antithrombotic drug. Conclusions These results revealed lack of implementation of VTE prophylaxis in one out of high-risk multiple myeloma patients with IMiD. Copyright © 2017 John Wiley & Sons, Ltd. key words—electronic healthcare records; lenalidomide; thalidomide; venous thromboembolism; multiple myeloma; pharmacoepidemiology; SNIIRAM; France Received 14 June 2016; Revised 12 December 2016; Accepted 19 January 2017 INTRODUCTION The risk of venous thrombosis in multiple myeloma (MM) is increased, in relation to increased blood viscosity, circulating immunoglobulin, production of inflammatory cytokines and monoclonal protein with procoagulant activity. 1 Moreover, drugs commonly used for MM further increase that risk. These include for instance immunomodulatory drugs IMiDs, such as lenalidomide and thalidomide, 2,3 and also *Correspondence to: Aurore Palmaro, Service de Pharmacologie Médicale et Clinique, 37, allées Jules Guesde, 31000 Toulouse, France. Email: aurore. palmaro@univ-tlse3.fr Presented at the 12th European Association for Clinical Pharmacology and Therapeutics Congress (EACPT 2015, Madrid, Spain, August 2015) and at the 10th Congress of General Practice (Paris, 31 March to 02 April 2016). Copyright © 2017 John Wiley & Sons, Ltd. pharmacoepidemiology and drug safety (2017) Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/pds.4180