Multiple myeloma mortality in Latin America: Heterogeneous patterns and challenges in cross-country comparisons

Differences in death certification practices may affect cross-country comparisons of multiple myeloma (MM) mortality estimates. In Latin America, where access to transplantation and novel therapies remains limited, MM mortality patterns have not consistently aligned with expected differences. We describe MM mortality rates across Latin American countries and compare them to those of Hispanic individuals in the United States (US).

In this population-based study, we analyzed mortality data from 15 Latin American countries (World Health Organization Mortality Database) and the US (National Center for Health Statistics data). MM deaths among adults (≥20 years) during 2008-2019 were examined using US Hispanic individuals as reference.

The highest mortality (per 100,000 persons) in Latin American countries was observed in Chile (4.12), Uruguay (4.11), and Costa Rica (3.57). Mortality for US Hispanic individuals was 3.8. Most countries exhibited lower or comparable mortality rate ratios (MMRs) relative to US Hispanic individuals. Stratified analyses by sex showed similar findings. However, this pattern was not consistent across age groups. Young adults (20-59 years) generally experienced higher mortality, particularly in Cuba (MRR=2.04, 95% CI=1.88-2.21; P_{heterogeneity}<0.0001). Countries with higher Human Development Index tended to exhibit mortality estimates more closely aligned with those of US Hispanic individuals.

MM mortality patterns across Latin America were heterogeneous and often lower than those observed among US Hispanic individuals, despite known differences in access to care. Strengthening MM surveillance systems is needed to improve the interpretation of mortality patterns across the region.