Mortality trends for chronic kidney disease and dementia in the United States, 1999–2020: a 22-year retrospective analysis

Background Chronic kidney disease (CKD) and dementia are major causes of morbidity and mortality among older adults and frequently coexist due to shared vascular and metabolic risk factors. Despite their clinical importance, national mortality trends for these conditions remain underexplored. This study aimed to examine temporal and demographic patterns of mortality among individuals with coexisting CKD and dementia in the United States from 1999 to 2020. Methods In this retrospective, population-based study, mortality data for adults aged ≥25 years were extracted from the Centers for Disease Control and Prevention’s Wide-ranging Online Data for Epidemiologic Research database. Deaths listing both CKD [International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10 N18.x)] and dementia (ICD-10 F01.x, F03, G30.x) as causes were included. Age-adjusted mortality rates (AAMRs) per 100 000 were calculated using the 2000 U.S. standard population. Temporal trends were analyzed using Joinpoint regression to estimate annual percent change and average annual percent change (AAPC) with P < 0.05 considered significant. Subgroup analyses were stratified by gender, race/ethnicity, age, region, and urbanization. Results Between 1999 and 2020, 170 375 deaths were attributed to CKD and dementia. The overall AAMR increased from 1.03 to 5.92 per 100 000 (AAPC 7.41%). Mortality increased significantly across both genders, older adults, and all census regions, peaking in 2012, briefly declining between 2012 and 2015, then rising during 2015 to 2020. Males had higher mortality (AAMR 4.24) than females (3.16). Non-Hispanic Black individuals exhibited the highest rate (6.20), followed by non-Hispanic White (3.35) and Hispanic (3.09) populations. The Midwest showed the highest regional burden (AAMR 3.90), while rural counties recorded greater mortality (3.89) than urban areas (3.49). Conclusion The increasing mortality trends show a close relationship between CKD and dementia. Thus, improving early diagnosis, ensuring equal access to care, and providing a holistic treatment approach targeting both the organs is key to enhancing optimal patient care and consequently reducing mortality.