Characterizing the landscape of hospitalizations for multiple myeloma in Spain: a retrospective analysis (2016-2023).

Multiple myeloma (MM) is a chronic hematological malignancy associated with substantial morbidity and healthcare utilization. We conducted a retrospective population-based study using the Spanish Minimum Basic Data Set to analyze MM-related hospitalizations in Spain. All hospitalizations with a diagnosis of MM during the study period were included. Demographic characteristics, comorbidities, complications, and outcomes were assessed, and temporal trends were evaluated using quasi-Poisson regression models. A total of 107,496 hospitalizations involving 43,383 unique patients were analyzed. Hospitalization rates increased significantly over the study period, from 25.1 to 34.6 per 100,000 population (p < 0.001). Median patient age at hospitalization was 73 years, and 47% were women. In-hospital mortality was 11%, decreasing from 13% in 2016 to 9.6% in 2023 despite an increasing comorbidity burden. Mortality increased with age, and marked regional variability was observed. These findings indicate a growing healthcare burden but improved survival, likely reflecting advances in MM treatment and supportive care.