Objective:

To examine long-term mortality trends and geographic inequities for advanced stages 4 and 4b of cardiovascular–kidney–metabolic syndrome in the U.S. from 1999 to 2023.

Key Findings:

• Age-adjusted mortality for stage 4 declined from 505.54 to 353.30 per 100,000 population from 1999 to 2023 (average annual percent change, −1.31%).
• Age-adjusted mortality for stage 4b declined from 45.95 to 33.98 per 100,000 during the same period (average annual percent change, −1.18%).
• Mortality trends reversed in the past decade, with increases in stage 4 and stage 4b after 2013 and 2015, respectively.
• Stage 4 mortality formed a high-burden belt across the Deep South and Appalachia, while stage 4b hotspots were more dispersed.

Interpretation:

Overall mortality from advanced CKM stages declined but showed a rebound in the past decade, highlighting significant geographic disparities that warrant attention.

Limitations:

• The study relies on death certificate data, which may have inaccuracies.
• The analysis does not account for potential confounding factors affecting mortality trends, such as socioeconomic status and access to healthcare.

Conclusion:

Surveillance of advanced CKM mortality trends and geographic disparities may inform targeted risk reduction strategies.