National Trends and Structural Inequities in Acute Kidney Injury Mortality: A Joinpoint Analysis of CDC WONDER Data, 1999–2023

ABSTRACT To evaluate the long‐term trends in acute kidney injury (AKI)‐related mortality among U.S. adults and quantify the associated demographic disparities, we analyzed mortality data from 1999 to 2023 in the Centers for Disease Control and Prevention (CDC) WONDER database. We calculated the age‐adjusted mortality rate (AAMR) per 100 000 population, and estimated the annual percent change (APC) as well as the average annual percent change (AAPC). Stratified analyses were conducted by sex, race/ethnicity, age, and geographic region. The results showed that the overall AAMR increased significantly from 1999 to 2008 (APC: 5.30%), decreased from 2008 to 2019(APC: −3.58%), and then rose sharply again from 2019 to 2023 (APC: 12.29%). Significant disparities were observed across different subgroups; however, in certain subgroups—such as males, non‐Hispanic Black individuals, residents of Southern U.S. states, and adults aged 85 years and older—mortality rates remained consistently the highest, and these disparities further widened during the COVID‐19 pandemic. These findings underscore the urgent need for targeted public health interventions to address inequalities in AKI outcomes, thereby improving health equity in this clinical domain.