Covid-19 Related Fatality and Risk Factors in Multiple Myeloma: A Multicenter Cohort Study

The distinctive clinical course and outcomes of COVID-19 infection in multiple myeloma patients are still not well established. In this study, we aimed to assess the clinical outcomes and associated factors of COVID-19 in patients with multiple myeloma (MM). This is a multi-center retrospective cohort study. Multiple myeloma patients treated in two tertiary centers were investigated, and the patients diagnosed with COVID-19 during follow-up were included. The main characteristics and clinical outcomes of patients were analyzed. A total of thirty patients were included for analysis. In this cohort, autologous hematopoietic stem cell transplantation (AHSCT) was performed in 63.3% of the patients, and 36.7% were in complete remission when COVID-19 was detected. The total fatality rate (FR) was 36%, and the COVID-19-related case fatality rate (CFR) was 30% for MM patients in our cohort. There was two non-COVIDrelated mortality. The CFR was associated with intensive care unit admission (26.7%, p< 0.001), mechanical ventilation (26.6%, p< 0.001), increased lactate dehydrogenase (p= 0.008) and lymphopenia (p= 0.042). Older age (> 65-years), stem cell transplantation, and comorbidities were not effective on the fatality rate. This study shows that the CFR rate was high in MM patients, irrespective of AHSCT status. Therefore, we suggest strict monitoring and adequate vaccination in this group. However, further studies, including vaccination data with a larger group of patients, are needed to clarify the literature.