Trends and disparities in ischemic heart disease and anemia-related mortality in adults aged ≥ 65 years in the United States from 1999 to 2023: A CDC wonder database analysis

Abstract Introduction: Ischemic heart disease and anemia are prevalent in older adults in the United States and, when concomitant, significantly increase the risk of morbidity and mortality. Anemia contributes to poor outcomes in ischemic heart disease by reducing the oxygen-carrying capacity of blood, leading to myocardial hypoxia, increased systemic inflammation, oxidative stress, and endothelial dysfunction. All of these contributions accelerate atherosclerosis and deleterious ventricular remodeling. Mortality trend analyses stratified by demographic and geographic factors concerning ischemic heart disease and anemia amongst the elderly in the United States are scarce. This study examines national mortality trends in adults aged ≥ 65 years with ischemic heart disease and anemia from 1999 to 2023. Methods: The CDC WONDER Multiple Cause-of-Death dataset (1999-2023) was used to analyze mortality trends in adults aged ≥ 65 years using ICD-10 codes for ischemic heart disease (I20-I25) and anemia (D55-D59, D60-D64). Results were stratified by place of death, year, sex, age group, race, census region, state, and urbanization. Age-adjusted mortality rates (AAMRs) were quantified per 100,000 persons by standardizing crude mortality rates (CMRs) with 95% confidence intervals (95%CI). Annual percent change (APC) and average annual percent change (AAPC) were calculated using Joinpoint regression software. Statistical significance was defined as a P value < 0.05. Results: A total of 266,717 ischemic heart disease and anemia-related deaths occurred in adults ≥ 65 years in the United States from 1999 to 2023. Most of the deaths occurred in medical facilities (41.67%), followed by nursing home/long term care facilities (30.92%), the decedent's home (21.09%), other/place of death unknown (3.31%), and hospices (3.00%). Overall AAMR decreased from 30.40 in 1999 to 21.69 in 2023 (AAPC: -1.44; 95%CI: -1.70 to -1.17). Men had a higher average AAMR (31.78) compared to women (20.92), while women saw a higher rate of decline (AAPC women: -2.30; 95%CI: -2.55 to -2.07; AAPC men:-0.77; 95%CI: -1.08 to -0.42). Average CMRs increased with age, as adults ≥ 85 years had the highest average CMR (96.97), followed by 75-84 year olds (26.56), and 65-74 year olds (7.38). All age groups saw decreasing AAMRs, with adults ≥ 85 years having the greatest rate of decline (AAPC adults ≥ 85 years: -1.98; 95%CI:- 2.22 to -1.71; AAPC adults 75-84 years: -1.20; 95%CI: -1.54 to -0.89; AAPC adults 65-74 years: -0.67; 95%CI: -0.99 to -0.43). Racially, non-Hispanic (NH) Black/African Americans had the highest average AAMR (30.79), followed by NH Whites (25.09), NH American indian/Alaska native (25.01), Hispanic/Latinos (21.32), and NH Asian/Pacific Islander (19.65). All of the race groups had declining AAMRs, with NH Asian/Pacific Islanders having the highest rate of decrease (AAPC NH Asian/Pacific Islander: -2.52; 95%CI: -2.88 to -1.96). Amongst census regions, the Midwest had the highest average AAMR (26.99), followed by the Northeast (26.83), the South (24.26), and the West (22.85). All census regions had declining AAMRs, with the Northeast having the greatest rate of decline (AAPC Northeast: -2.13; 95%CI: -2.55 to -1.80). State-wise, California had the greatest number of deaths at 31,357, accounting for 11.76% of deaths. From 1999-2020, rural areas had a higher average AAMR (29.53) compared to urban areas (24.63). Urban and rural areas both had decreasing AAMRs, with urban areas having a greater rate of decline (AAPC urban: -1.88; 95%CI: -2.14 to -1.60; AAPC rural: -1.07; 95%CI:-1.50 to -0.65). Conclusion: Although ischemic heart disease and anemia-related mortality rates amongst the elderly in the United States decreased from 1999 to 2023, stark discrepancies among demographic and geographical stratifications were noted. Additional research into the mechanistic interplay between ischemic heart disease and anemia and its associated mortality is critical to address these discrepancies. Public health strategies to address vulnerable populations are vital to further improve health outcomes related to ischemic heart disease and anemia.