Trends and disparities in anemia and pneumonia-related mortality in the United States from 1999 to 2023: A CDC wonder database analysis

Abstract Introduction: Anemia and pneumonia are prevalent and often coexisting conditions that contribute significantly to morbidity and mortality, particularly among older adults in the United States. Anemia disrupts immune function and oxygen delivery, increasing the risk of infections such as pneumonia, which remains a leading cause of hospitalization and death, particularly in elderly populations. Despite advancements in medical care and preventive strategies, the combined mortality burden of anemia and pneumonia has not been explored at the national level. This study aims to evaluate trends and disparities in anemia and pneumonia-related mortality among U.S. adults ≥ 65 years from 1999 to 2023 using data from the CDC WONDER database. Methodology: A retrospective analysis using death certificate data in the United States from the CDC WONDER database spanning 1999 to 2023 among adults aged ≥ 65 years was conducted. Using ICD-10 codes, anemia (D55-D59, D60-D64) and pneumonia (J12-J18) were included as contributing causes of death. Age-adjusted mortality rates (AAMRs), annual percent changes (APCs), and average annual percent changes (AAPCs) were calculated using Joinpoint regression model software. Results were stratified by place of death, year, sex, race, census region, and state and quantified per 100,000 persons with 95% confidence intervals (95% CI). A p-value < 0.05 was determined to be statistically significant. Results: From 1999 to 2023, a total of 106,982 anemia and pneumonia-related deaths occurred amongst adults aged ≥ 65 years in the United States. The greatest number of deaths occurred in medical facilities at 72,872 (68.12%), followed by nursing home/long-term care facilities at 22,241 (20.79%), the decedent's home at 7,122 (6.66%), hospices at 2,823 (2.64%), and other/place of death unknown at 1,924 (1.80%). Overall AAMRs decreased from 13.64 in 1999 to 6.78 in 2018 (APC: -4.28; 95%CI: -4.95 to -3.76), followed by an increase to 12.20 (APC: 23.55; 95%CI: 14.81 to 28.4) and lastly a decrease to 8.32 in 2023 (APC: -17.95; 95%CI: -25.79 to -10.3). In summary, this resulted in declining AAMRs spanning from 1999 to 2023 (AAPC: -2.44; 95% CI: -3.15 to -1.96). Men had a higher average AAMR (12.52) compared to women (8.58), and a higher rate of decrease (AAPC men: -2.55; 95%CI: -3.26 to -2.06; AAPC women: -1.97; 95%CI: -2.66 to -1.28). Racially, non-Hispanic (NH) Black/African Americans had the highest average AAMR (14.73), followed by NH Asian/Pacific Islanders (12.02), Hispanic/Latino (10.70), and NH Whites (9.47). All of the racial groups saw declining mortality rates, with NH Asian/Pacific Islanders observing the highest rate of decrease (AAPC NH Asian/Pacific Islander: -3.49; 95%CI: -4.26 to -2.63). Regionally, average AAMRs were highest in the West (10.47), followed by the South (10.45), the Midwest (9.82), and the Northeast (9.28). All the census regions saw declining mortality rates, with the Midwest experiencing the greatest rate of decrease (AAPC Midwest: -3.04; 95%CI: -4.13 to -2.24). States in the top 90th percentile of deaths include California, Texas, New York, Florida, and Ohio, while states in the bottom 10th percentile of deaths include Alaska, Wyoming, Vermont, Montana, and the District of Columbia. Conclusion: From 1999 to 2023, anemia and pneumonia-related mortality rates for adults aged ≥65 years declined. The highest risk of mortality was observed among men, NH Black/African Americans, and those residing in the West. States with the most deaths were California, Texas, New York, Florida, and Ohio. These disparities highlight the need for a more comprehensive and tailored approach to implementing equitable health care for at-risk populations.