Key Takeaways

• Pneumonia-related hospital admissions among patients with multiple myeloma (MM) were associated with 11.4% in-hospital mortality, a median length of stay of 6 days, and median costs exceeding $48 000.
• Inflation-adjusted annual costs for pneumonia-related admissions in MM increased 181.5%, from $855 million in 2006 to $2.4 billion in 2019, despite declining mortality.
• Patients with MM hospitalized for pneumonia or COVID-19 were older, frailer, and experienced higher mortality than patients without MM.

Multiple myeloma remains associated with a substantial burden of infectious complications despite advances in treatment and survival. A new analysis of US hospitalization data from 2006 through 2022 found that pneumonia-related admissions among patients with MM are becoming increasingly costly, while mortality, although declining over time, remains high. The findings highlight persistent disparities and the need for strategies to reduce infection-related hospitalizations in this vulnerable population.

National Trends Show Increasing Cost Burden of Pneumonia in MM

Investigators conducted a serial cross-sectional study using the Healthcare Cost and Utilization Project National Inpatient Sample (HCUP-NIS) to evaluate pneumonia-related hospital admissions among adults with and without MM between 2006 and 2022. Patients were identified using ICD-9 and ICD-10 diagnostic codes, with national estimates generated using HCUP discharge weights.

The analysis identified 284 450 weighted pneumonia-related admissions among patients with MM. Across the study period, these admissions were associated with an in-hospital mortality rate of 11.4%, a median hospital length of stay of 6 days, and a median inflation-adjusted cost of $48 119.

Between 2006 and 2019, median admission costs increased from $36 361 to $50 905. During the same period, in-hospital mortality declined from 13.9% to 9.1%. Despite improvements in mortality, the total annual inflation-adjusted cost of pneumonia-related admissions in MM rose sharply from $855 million to $2.4 billion, representing a 181.5% increase.

The proportion of pneumonia admissions attributable to patients with MM increased by 66.4% from 2006 to 2019 (r² = 0.95; P < .001). Similarly, the proportion of total pneumonia-related costs attributable to MM admissions increased by 53.9% (r² = 0.67; P < .001).

The investigators also evaluated COVID-19-related admissions from 2020 through 2022. They identified 22 935 weighted admissions among patients with MM. These admissions were associated with a mortality rate of 17.5%, a median length of stay of 6 days, and a median cost of $59 032.

Compared with patients without MM, those in both the pneumonia and COVID-19 MM cohorts were more likely to be older, male, non-White, and frail. They also experienced significantly higher mortality rates (P < .001).

Data Highlight Ongoing Burden of Serious Infections

The findings underscore the growing economic and clinical impact of infectious complications in MM. Although advances in myeloma therapy have improved survival, patients remain at elevated risk for severe infections because of disease-related immune dysfunction and treatment-associated immunosuppression.

For payers and managed care stakeholders, the substantial rise in hospitalization costs represents an increasingly important component of total MM care expenditures. The increase in annual costs occurred despite reductions in mortality, suggesting that infection-related resource utilization remains significant.

The observed demographic and frailty-related disparities may help identify patient populations at greatest risk for adverse outcomes. Incorporating frailty assessment into clinical decision-making and care management programs could support more targeted interventions.

The authors suggest that preventive approaches aimed at reducing infection-related admissions warrant further investigation. Potential strategies include antimicrobial prophylaxis, intravenous immunoglobulin use, and vaccination programs. Effective prevention could reduce hospitalization rates, improve outcomes, and lessen the financial burden associated with pneumonia and other serious infections in MM.

Researchers Advocate for Prevention-Focused Approaches

The study authors concluded that pneumonia-related admissions among patients with MM are becoming increasingly expensive and continue to be influenced by demographic and comorbidity-related disparities. They noted that patients with MM hospitalized for pneumonia or COVID-19 were significantly frailer and experienced higher mortality than comparable patients without MM. The investigators further emphasized the need for research evaluating preventive interventions, including antimicrobial prophylaxis, intravenous immunoglobulin, and vaccination strategies.

Findings Point to Opportunities for Reducing Hospitalizations

Pneumonia remains a major driver of hospitalization, mortality, and health care spending among patients with MM. While mortality rates have improved over time, hospitalization costs continue to rise substantially, highlighting the need for targeted preventive strategies and interventions to reduce infection-related burden in this population.

Reference

Brunner JR, Seiler K, Pianko MJ. Trends in U.S. pneumonia-related admissions among patients with multiple myeloma (2006–2022). Presented at the 2026 American Society of Clinical Oncology Annual Meeting; May 29-June 2, 2026. Chicago, Illinois.