TY - JOUR
T1 - Hemoglobin, Anemia, and Cognitive Function
T2 - The Atherosclerosis Risk in Communities Study
AU - Schneider, Andrea L.C.
AU - Jonassaint, Charles
AU - Sharrett, A. Richey
AU - Mosley, Thomas H.
AU - Astor, Brad C.
AU - Selvin, Elizabeth
AU - Coresh, Josef
AU - Gottesman, Rebecca F.
N1 - Funding Information:
Funding: The Atherosclerosis Risk in Communities Study is carried out as a collaborative study supported by the National Heart, Lung, and Blood Institute contracts (HHSN268201100005C, HHSN268201100006C, HHSN268201100007C, HHSN268201100008C, HHSN268201100009C, HHSN268201100010C, HHSN268201100011C, and HHSN268201100012C). A.L.C.S. was supported by the NIH/NHLBI training grant T32HL007024.
Publisher Copyright:
© 2015 The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved.
PY - 2016/6/8
Y1 - 2016/6/8
N2 - Background. Our objective was to characterize the relationship of low and high hemoglobin concentrations and normocytic, microcytic, and macrocytic anemia with cross-sectional cognition and change in cognition over a median of 6 years. Methods. Cross-sectional and prospective analyses of 13,133 participants (mean age 57 years, 56% women, 24% black, 10% anemia) in the Atherosclerosis Risk in Communities (ARIC) study (baseline 1990-1992) were carried out. Anemia was defined as hemoglobin concentrations lower than 13g/dl for men and lower than 12g/dl for women and was subclassified as normocytic (mean corpuscular volume [MCV] 80-100 fL), microcytic (MCV < 80 fL), and macrocytic (MCV > 100 fL). Cognition was assessed by delayed word recall test (DWRT), digit symbol substitution test (DSST), word fluency test (WFT), and global Z-score at Visit 2 (1990-1992) and Visit 4 (1996-1998). Adjusted linear regression models and splines were used. Results. Cross-sectionally, anemia overall was associated with lower cognitive test scores on DSST and global Z-score among men and women (all p <. 05), but not on DWRT or WFT. Anemia subtypes were associated similarly with cognition, with strongest associations for the DSST and global Z-score. Additionally, elevated hemoglobin level was associated with nonsignificantly worse cognition in cross-sectional analyses, suggesting a nonlinear association of hemoglobin with cognition. In contrast, anemia overall and anemia subtypes were not associated with cognition in prospective analyses (all p >. 05). Conclusions. There was a cross-sectional, but not prospective, nonlinear association between hemoglobin concentrations and cognitive function, although only associations of low levels of hemoglobin (anemia) were statistically significant. Subtypes of anemia had similar magnitudes of associations with cognition.
AB - Background. Our objective was to characterize the relationship of low and high hemoglobin concentrations and normocytic, microcytic, and macrocytic anemia with cross-sectional cognition and change in cognition over a median of 6 years. Methods. Cross-sectional and prospective analyses of 13,133 participants (mean age 57 years, 56% women, 24% black, 10% anemia) in the Atherosclerosis Risk in Communities (ARIC) study (baseline 1990-1992) were carried out. Anemia was defined as hemoglobin concentrations lower than 13g/dl for men and lower than 12g/dl for women and was subclassified as normocytic (mean corpuscular volume [MCV] 80-100 fL), microcytic (MCV < 80 fL), and macrocytic (MCV > 100 fL). Cognition was assessed by delayed word recall test (DWRT), digit symbol substitution test (DSST), word fluency test (WFT), and global Z-score at Visit 2 (1990-1992) and Visit 4 (1996-1998). Adjusted linear regression models and splines were used. Results. Cross-sectionally, anemia overall was associated with lower cognitive test scores on DSST and global Z-score among men and women (all p <. 05), but not on DWRT or WFT. Anemia subtypes were associated similarly with cognition, with strongest associations for the DSST and global Z-score. Additionally, elevated hemoglobin level was associated with nonsignificantly worse cognition in cross-sectional analyses, suggesting a nonlinear association of hemoglobin with cognition. In contrast, anemia overall and anemia subtypes were not associated with cognition in prospective analyses (all p >. 05). Conclusions. There was a cross-sectional, but not prospective, nonlinear association between hemoglobin concentrations and cognitive function, although only associations of low levels of hemoglobin (anemia) were statistically significant. Subtypes of anemia had similar magnitudes of associations with cognition.
KW - Anemia
KW - Cognition
KW - Cognitive aging
KW - Epidemiology
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U2 - 10.1093/gerona/glv158
DO - 10.1093/gerona/glv158
M3 - Article
C2 - 26363510
AN - SCOPUS:84973441954
VL - 71
SP - 772
EP - 779
JO - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
JF - Journals of Gerontology - Series A Biological Sciences and Medical Sciences
SN - 1079-5006
IS - 6
ER -