Decrease in early mortality for newly diagnosed multiple myeloma patients in the Netherlands: a population-based study.

Identification of risk factors for early mortality (EM) in multiple myeloma (MM) patients may contribute to different therapeutic approaches in patients at risk for EM. This population-based study aimed to assess trends in EM and risk factors for EM among MM patients diagnosed in the Netherlands. All MM patients, newly diagnosed between 1989 and 2018, were identified in the Netherlands Cancer Registry. Patients were categorized into three calendar periods (1989-1998, 1999-2008, 2009-2018) and into five age groups (≤65, 66-70, 71-75, 76-80, >80 years). EM was defined as death by any cause ≤180 days post-diagnosis. We included 28,328 MM patients (median age 70 years; 55% males). EM decreased from 22% for patients diagnosed in 1989-1998 to 13% for patients diagnosed in 2009-2018 (P < 0.01) and this decrease was observed among all age groups. Exact causes of death could not be elucidated. Besides patient's age, we found that features related to a more aggressive disease presentation, and patient characteristics reflecting patients' physical condition were predictive of EM. In summary, EM decreased from 1999 onwards. Nevertheless, EM remains high, especially for patients aged >70 years. Therefore, novel strategies should be explored to improve the outcome of patients at risk for EM.