Abstract Rationale Influenza and pneumonia, ICD codes J09-J18, are among the fifteen leading causes of death in the United States (US). The Social Vulnerability Index (SVI), developedby the Centers for Disease Control and Prevention (CDC), is a composite, percentile-basedmeasure of county-level sociodemographic vulnerability to disasters. This study aims to evaluate the association between county-level social vulnerability, as measured by the SVI, and pneumonia mortality in the US. Methods Pneumonia mortality data for all US counties from 2020 to 2025 were obtainedfrom the National Center for Health Statistics (NCHS), provided by the CDC. The overall SVI is calculated by summing four subindices (Socioeconomic Status; HouseholdComposition Minority Status and Housing Type 4th most vulnerable =0.75-1.00). Associations between pneumonia mortality and both the overall SVI and its four subindices were analyzed using negative binomial regression. Results From 2020 to 2025, a total of 272,786 people died from pneumonia in the US.The 5-year crude pneumonia mortality rate was 13.74 per 100,000 population. Among all US counties, Cherokee County, South Carolina had the highest mortality rate (77.44 per100,000). Luna County, New Mexico had the highest SVI score (overall SVI = 0.9997; where1 represents the highest vulnerability), whereas Monroe County, Illinois had the lowest(overall SVI = 0.001). Counties with higher SVI scores and pneumonia mortality were predominantly clustered in the South and Southwest regions of the US. In our analysis, theoverall SVI showed a positive association with pneumonia mortality (Incidence Rate RatioIRR, Q4 = 1.27 95% CI: 1.20-1.35; reference: Q1). A relationship, increased in a stepwisemanner, was observed for the socioeconomic vulnerability subindex, with IRRs of 1.221.16-1.29 for Q2, 1.33 1.25-1.41 for Q3, and 1.58 1.48-1.69 for Q4. A similar trend was found for the household composition and disability subindex (IRR, Q2 = 1.13 1.08-1.19;Q4 = 1.38 1.30-1.47). In contrast, the racial and ethnic minority status subindex was inversely associated with pneumonia mortality (IRR, Q4 = 0.73 0.69-0.77). Conclusion These findings highlight that increased social vulnerability—particularly in the domain of socioeconomic disadvantage—is closely associated with higher pneumonia mortality risk. Focused public health strategies targeting socially vulnerable areas may becritical to reducing pneumonia-related outcomes in the US. A counterintuitive associationobserved between minority status and pneumonia mortality warrants furtherinvestigations. This abstract is funded by: None
Wu et al. (Fri,) studied this question.