Abstract Body: Introduction: Cardiac arrest (CA), combined with acute respiratory failure (ARF), magnifies mortality. Stratified analyses concerning the interrelated national mortality trends and disparities related to CA and ARF are limited. Our study analyzes national mortality trends in adults aged ≥ 25 years with CA and ARF from 1999 to 2023.

Methods: The CDC WONDER Multiple Cause-of-Death dataset (1999-2023) was used to analyze mortality trends in adults aged ≥ 25 years using ICD-10 codes for CA (I46) and ARF (J80, J96.0, J96.9). Results were stratified by place of death, year, along with demographic and geographical categorizations. Age-adjusted mortality rates (AAMR) were quantified per 100,000 persons with 95% confidence intervals (95%CI). Annual percent change (APC) and average annual percent change (AAPC) were calculated using Joinpoint regression software.

Results: A total of 807,236 CA and ARF-related deaths occurred from 1999 to 2023,
majorly occurring in medical facilities (80.1%). Overall AAMR remained stable from 1999 to 2018, followed by increases until 2021 and decreases thereafter until 2023 (AAPC: 3.0; 95%CI: 2.2 to 4.0). Adults ≥ 65 years had the highest average AAMR, though 25-44 year olds had the highest rate of increase (AAPC: 5.6; 95%CI: 4.8 to 6.4). Men had higher average AAMR, though women had a higher rate of increase (AAPC: 3.3; 95%CI: 2.7 to 3.8). Racially, non-Hispanic (NH) Black/African Americans had the highest average AAMR, though NH American Indian/Alaska Natives had the highest rate of increase (AAPC: 4.9; 95%CI: 3.9 to 6.1). Regionally, the West had the highest average AAMR, though the Midwest had the highest rate of increase (AAPC: 4.5; 95%CI: 4.0 to 5.0). California saw the highest percentage of deaths (20.5%). From 1999 to 2020, urban areas had higher average AAMR, though rural areas had a higher rate of increase (AAPC: 5.5; 95%CI: 4.7 to 6.3).

Conclusion: CA and ARF-related mortality rates have generally increased from 1999 to 2023, with periods of stability and decreases interspersed throughout. Disparities among demographic and geographical stratifications were significant. Increased research to address the disparities and public health policy changes to address at-risk communities is critical.