What Constitutes Normal Hemoglobin Concentrations in Community-Dwelling Older Adults?
To assess the relationship between hemoglobin concentration and cause-specific mortality.



Cohort study.



Data from the government-sponsored Annual Geriatric Health Examination Program.



Community-dwelling Taipei citizens aged 65 and older followed up between 2006 and 2010 (N = 77,532).



Mortality was determined by matching participants' medical records with national death files. Cox proportional hazards regression models were used to evaluate the relationship between hemoglobin concentration (World Health Organization (WHO)-defined anemia and 7 hemoglobin concentrations) and cause-specific mortality.



The mortality risk of WHO-defined anemia increased substantially in both sexes for all-cause and cancer mortalities (men, hazard ratio (HR) = 1.86, 95% confidence interval (CI) = 1.71-2.02 for all-cause mortality; HR = 1.94, 95% CI = 1.69-2.22 for cancer mortality; for women, HR = 1.63, 95% CI = 1.43-1.86 for all-cause mortality; HR = 1.74, 95% CI = 1.38-2.19 for cancer mortality). Men with hemoglobin concentrations of 15.0 to 15.9 g/dL and women with hemoglobin concentrations of 13.0 to 13.9 g/dL had the lowest risks of all-cause, cardiovascular, and cancer mortality. Risks of all-cause and cancer mortality increased significantly when hemoglobin concentrations were less than 14 g/dL in men and less than 12 g/dL in women. Even mild anemia (11.0-11.9 g/dL) was associated with greater mortality risk. Stratification according to age, body mass index, estimated glomerular filtration rate, and presence of comorbidities did not lead to any substantial changes.



Hemoglobin concentrations associated with optimal survival in older adults were identified and additional data provided regarding the relationship between hemoglobin concentrations and cause-specific mortality risks in older adults.
Department of Dermatology, Taipei Veterans General Hospital, Taipei, Taiwan.|Institutes of Public Health, National Yang-Ming University, Taipei, Taiwan.|Department of Public Health, National Yang-Ming University, Taipei, Taiwan.|Department of Dermatology, Heping Fuyou Branch, Taipei City Hospital, Taipei, Taiwan.
Chen-Yi
CY
Wu
Institutes of Public Health, National Yang-Ming University, Taipei, Taiwan.|Department of Public Health, National Yang-Ming University, Taipei, Taiwan.|Department of Education and Research, Taipei City Hospital, Taipei, Taiwan.
Hsiao-Yun
HY
Hu
Institutes of Public Health, National Yang-Ming University, Taipei, Taiwan.|Department of Public Health, National Yang-Ming University, Taipei, Taiwan.
Yiing-Jenq
YJ
Chou
Hospital and Health Care Administration, National Yang-Ming University, Taipei, Taiwan.|Department of Education and Research, Taipei City Hospital, Taipei, Taiwan.
Nicole
N
Huang
Institutes of Public Health, National Yang-Ming University, Taipei, Taiwan.|Department of Public Health, National Yang-Ming University, Taipei, Taiwan.|Department of Education and Research, Taipei City Hospital, Taipei, Taiwan.
Yi-Chang
YC
Chou
Division of Gastroenterology and Hepatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.|School of Medicine, National Yang-Ming University, Taipei, Taiwan.
Chung-Pin
CP
Li
D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000453:epidemiology* / Q000401:mortality; D002423:Cause of Death; D005260:Female; D015577:Geriatric Assessment; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D057187:Independent Living; D008297:Male; D012016:Reference Values; D013624:Taiwan / Q000453:epidemiology
D006454:Hemoglobins
all-cause mortality; cancer mortality; cardiovascular mortality; hemoglobin; older adults