Incidência e fatores associados a eventos tromboembólicos em portadores de mieloma múltiplo em uso de imunomoduladores: coorte histórica.

Abstract

Multiple myeloma (MM) is a cancer of plasma cells which comprises 10% to 15% of all hematological malignancies worldwide. Significant survival improvements for these patients have been conquered over the past years due to the approval of novel therapeutic approaches, on the other hand, complications may appear in the treatment of these patients and must be handled carefully. Particularly, the use of immunomodulators increases the risk of venous thromboembolism (VTE) in these patients. The main aim of this study was to determine incidence and associated factors to VTE among MM patients using immunomodulators. Besides, to compare the performance of three risk assessment tools for VTE in MM patients. This is an observational and a historical cohort study. The study was developed in a hematology outpatient setting of a teaching hospital and a private hematology clinic. Data collection was conducted through the analysis of medical records for the period of 12 months since the initiation of treatment with immunomodulators of patients with MM diagnosis between 2009 and 2019 and included the following variables: age, sex, skin-color, ISS stage system, body mass index, history of surgery, fractures, sepsis, VTE, traumatic injury, date of MM diagnosis, use of erythropoietin, of dexamethasone, use of central venous catheter, thromboprophylaxis, chemotherapy and comorbidities. Variables were used for calculating the risk assessment tools for VTE: IMPEDE VTE, SAVED and IMWG/NCCN. Data regarding the thromboembolism events was identified from medical records. Statistical descriptive analysis, Cox proportional hazard model and ROC curve (Receiver Operating Characteristic) were performed using the software SPSS. 131 patients were included with mean age of 61.5 years (SD=11.3), 51.9% were female and 97.7% used thalidomide. 98 patients were on thromboprophylaxis. 9 patients presented VTE, with 12-month cumulative incidence of 6.97% (95% CI 3.41-12.24). Associated factors included recent sepsis, recent traumatic injury, previous VTE and thromboprophylaxis. Regarding risk assessment tools, the IMPEDE VTE (Area under the curve - AUC 0.8; Confidence Interval -95% CI 0.66-0.95) outperformed the SAVED (AUC 0.69; 95% CI 0.49-0.89) and the IMWG/NCCN (AUC 0.68; 95% CI 0.48-0.88). Our data revealed low incidence of VTE among Brazilian MM patients and IMPEDE VTE showed better discriminatory ability for development of VTE. This study had limitations such as underdiagnosis of VTE due to patients attending other health facilities. More studies are necessary to assess the applicability of VTE risk prediction tools in clinical practice and effective strategies to avoid the occurrence of VTE in Brazilian MM patients.