Abstract
Multiple myeloma (MM) is a plasma cell malignancy frequently complicated by renal impairment, which substantially worsens prognosis. Although therapeutic advances have improved MM survival, renal failure remains a major contributor to adverse outcomes. This study examined long-term trends and demographic disparities in mortality among U.S. decedents with MM listed as the underlying cause of death and renal failure listed as a contributing cause. Mortality data for adults aged ≥ 45 years from 1999 to 2023 were obtained from the CDC Wide-ranging Online Data for Epidemiologic Research (WONDER) database. Deaths were identified using ICD-10 codes, with MM (C90.0) as the underlying cause and renal failure (N17-N19) as a contributing cause. Age-adjusted mortality rates (AAMRs) and crude mortality rates (CMRs) were calculated by sex, race/ethnicity, region, age group, and urbanization level. Temporal trends were evaluated using Joinpoint regression to estimate annual percent change (APC) and average annual percent change (AAPC). Overall mortality declined from 1999 to 2023, with the AAMR decreasing from 2.39 to 1.60 per 100,000 population (AAPC: -1.30). Despite this improvement, substantial disparities persisted. Males consistently exhibited higher AAMRs than females. Non-Hispanic Black individuals had the highest race-specific mortality rates. Residents of nonmetropolitan areas and those living in the Midwest experienced persistently higher mortality. Age-stratified analyses showed declining trends in most age groups, while adults aged ≥ 85 years demonstrated a modest recent increase. Mortality among U.S. adults with MM listed as the underlying cause of death and renal failure as a contributing cause declined between 1999 and 2023. However, persistent disparities by sex, race/ethnicity, region, urbanization, and age remain. These findings highlight the need for targeted strategies to reduce the burden of renal complications among high-risk MM populations.