Longitudinal Changes in Cardiovascular-Kidney-Metabolic Syndrome Stages and Their Impact on Outcomes: A Nationwide Cohort Study.

The impact of longitudinal changes in cardiovascular-kidney-metabolic (CKM) stage remains unclear. This study evaluated the association between CKM stage progression and clinical outcomes. : We used the Korean National Health Insurance Database to identify adults aged ≥ 20 years who underwent two health checkups between 2009 and 2012. CKM stages were assessed at both time points and categorized as decreased, maintained, or increased over a 1-2-year interval. The primary outcome was a composite of all-cause death, heart failure, stroke, and myocardial infarction, evaluated over a mean follow-up of 11.05 years. : Among 877,537 participants, 15.3% experienced CKM stage progression. Compared to the maintained group, the increased group had a higher risk of the composite outcome (HR: 1.071, 95% CI: 1.050-1.092). While men had a higher rate of progression, women showed greater risk of clinical events (HR: 1.124 vs. 1.040). While stage progression was more frequent in younger adults, older individuals in the increased group progressed to more advanced stages and experienced higher rates of adverse outcomes. : CKM stage progression is independently associated with increased risk of mortality and cardiovascular events, particularly in women and older adults. Serial CKM assessment may help identify high-risk individuals for early intervention.