Trends and disparities in mortality due to coexisting respiratory infections and multiple myeloma among middle-aged and older adults in the United States.

Abstract

e19541 Background: Patients with multiple myeloma (MM) are highly susceptible to respiratory infections due to disease- and treatment-related immunosuppression. Mortality due to coexisting respiratory infections and MM remains understudied, and national trends and sociodemographic disparities among middle-aged and older adults in the United States (US) are poorly characterized. Methods: We analyzed CDC WONDER mortality data (1999–2020) to identify deaths among U.S. middle-aged (55–74 years) and older adults (≥75 years) in which both respiratory infections and multiple myeloma were listed as causes of death on death certificates. Causes of death were identified using ICD-10 codes. Age-adjusted mortality rates (AAMRs) per 100,000 population were calculated overall and stratified by sex, age group, race/ethnicity, and state. Temporal trends were assessed using Joinpoint regression to estimate annual percent change (APC), with statistical significance defined as p ≤0.05. Results: From 1999 to 2020, 21,930 deaths due to coexisting respiratory infections and MM were identified. Mortality declined significantly from 1999 to 2012 (APC −4.14%, p <0.05) but increased thereafter, peaking in 2020 (AAMR: 1.40). Males accounted for 58.9% of deaths and had nearly two-fold higher mortality than females (AAMR: 1.94 vs. 0.98), with a significant rise from 2015 to 2020 (APC +4.53%, p =0.045), while female trends remained stable. Older adults (≥75 years) had higher mortality than those aged 55–74 years, despite long-term declines in both groups. Black or African American individuals experienced persistently higher mortality with a significant increase after 2012 (APC +4.10%, p =0.02), and Hispanic individuals showed a sharp rise from 2018 to 2020 (APC +29.9%, p =0.003), whereas mortality among White and Asian or Pacific Islander populations remained stable or declined. State-level analyses demonstrated over two-fold variation, with the highest absolute burden in California, Texas, New York, and Florida. Conclusions: Mortality due to coexisting respiratory infections and MM among middle-aged and older adults declined over the past two decades but showed concerning recent increases, particularly among males, Black, and Hispanic populations. Persistent racial and geographic disparities underscore the need for targeted infection prevention strategies and equitable supportive care for high-risk MM populations.