Anemia, Iron Deficiency, and Cause-Specific Mortality: The Atherosclerosis Risk in Communities Study
Language
English
Publication Date
1-1-2024
Journal
Gerontology
DOI
10.1159/000539973
PMID
39047718
PMCID
PMC11493523
PubMedCentral® Posted Date
7-24-2025
PubMedCentral® Full Text Version
Author MSS
Abstract
Introduction: Anemia is a risk factor for all-cause mortality in older adults. Iron deficiency may also be associated with adverse outcomes, independent of its role in causing anemia. This study tested the hypotheses that anemia, and low ferritin among non-anemic participants, were associated with all-cause and cause-specific mortality in a community-based cohort of older adults.
Methods: Fasting blood was obtained from 5,070 ARIC participants (median age: 75 years) in 2011-2013. Anemia was defined by hemoglobin concentrations < 12 g/dL in women and < 13 g/dL in men. We classified 4,020 non-anemic participants by quartiles of plasma ferritin, measured by the SomaScan proteomics platform. Cox proportional hazards regression was used. Mortality was ascertained via phone calls with proxies as part of twice-yearly cohort follow-up, surveillance of local hospital discharge indexes, state death records, and linkage to the National Death Index.
Results: Of the total participants, 21% had anemia at baseline. Over a median of 7.5 years, there were 1,147 deaths, including 357 due to cardiovascular disease (CVD), 302 to cancer, and 132 to respiratory disease. Compared to those with normal hemoglobin, participants with anemia had a higher risk of all-cause mortality (hazard ratio 1.81 [95% CI: 1.60-2.06]), and mortality due to CVD (1.77 [1.41-2.22]), cancer (1.81 [1.41-2.33]), and respiratory disease (1.72 [1.18-2.52]) in demographics-adjusted models. In fully adjusted models, associations with all-cause mortality (1.37 [1.19-1.58]) and cause-specific mortality were attenuated. In non-anemic participants, lower ferritin levels were not associated with all-cause or cause-specific mortality, though associations were observed among participants with lesser evidence of inflammation (CRP below the median level of 1.9 mg/L) and for cancer mortality in men only.
Conclusion: Anemia is common among older adults and is associated with all-cause mortality, as well as mortality due to CVD, cancer, and respiratory disease. Our results do not provide evidence that iron deficiency, independent of anemia, is associated with mortality in this population.
Keywords
Humans, Male, Female, Aged, Cause of Death, Ferritins, Risk Factors, Atherosclerosis, Proportional Hazards Models, Hemoglobins, Cardiovascular Diseases, Anemia, Iron-Deficiency, Anemia, Neoplasms, Aged, 80 and over, United States, Iron Deficiencies, Respiratory Tract Diseases, Anemia, Ferritin, Iron, Mortality
Published Open-Access
yes
Recommended Citation
Cannon, Ethan J; Misialek, Jeffrey R; Buckley, Leo F; et al., "Anemia, Iron Deficiency, and Cause-Specific Mortality: The Atherosclerosis Risk in Communities Study" (2024). Faculty, Staff and Students Publications. 6728.
https://digitalcommons.library.tmc.edu/baylor_docs/6728