Abstract Body (Do not enter title and authors here): Background:
Chronic kidney disease (CKD) stage 3 and above is strongly linked with increased cardiovascular mortality. Myocardial infarction (MI) in this population carries a particularly poor prognosis. However, long-term trends in MI mortality among CKD patients—and how these vary by sex and race remain underexplored.

Hypothesis:
We hypothesized that MI mortality among patients with CKD stage 3 or higher has declined over time, but with persistent disparities by sex and race. We aimed to characterize these temporal patterns and identify inflection points using joinpoint regression.

Methods:
Using CDC WONDER data from 1999 to 2020, we extracted age-adjusted mortality rates (AAMRs) for adults aged ≥25 years with advanced CKD and MI. AAMRs were stratified by sex (male, female) and race (White, Black, Asian/Pacific Islander, American Indian/Alaska Native, Hispanic). Linear and joinpoint regression (1 allowed inflection) were used to estimate slope coefficients (β), 95% confidence intervals (CI), and trend shifts.

Results:
In sex-stratified analyses, mortality declined in both groups: males (β = -0.021, p = 0.036) with early steep decline (slope1 = -0.331) plateauing after 2005 (slope2 = -0.017); females showed greater sustained decline (β = -0.022, p = 0.001, R2 = 0.423). Among racial groups, Black individuals had the sharpest initial decline (slope1 = -1.65) and continued improvement (slope2 = -0.12, p < 0.001). Asian/Pacific Islander and American Indian/Alaska Native groups showed modest declines (slope2 ≈ -0.05, p < 0.01). White patients had stable mortality (slope2 = -0.006, NS). Hispanic mortality declined until 2017 (slope1 = -0.068, p < 0.001), then rose (slope2 = +0.105, NS).

Conclusions:
From 1999–2020, MI-related mortality in advanced CKD declined overall, with more consistent reductions among females. Black individuals demonstrated the greatest mortality reduction, though they started at the highest baseline. In contrast, White mortality remained stable, and a concerning uptick was observed in Hispanic populations post-2017. These trends emphasize the need for tailored public health interventions to address persisting disparities in cardiovascular outcomes among CKD patients.