title: Decreased hemoglobin levels, cerebral small-vessel disease, and cortical atrophy: among cognitively normal elderly women and men.
abstract: BACKGROUND
  Decreased hemoglobin levels increase the risk of developing dementia among the elderly. However, the underlying mechanisms that link decreased hemoglobin levels to incident dementia still remain unclear, possibly due to the fact that few studies have reported on the relationship between low hemoglobin levels and neuroimaging markers. We, therefore, investigated the relationships between decreased hemoglobin levels, cerebral small-vessel disease (CSVD), and cortical atrophy in cognitively healthy women and men.
  
  
  METHODS
  Cognitively normal women (n = 1,022) and men (n = 1,018) who underwent medical check-ups and magnetic resonance imaging (MRI) were enrolled at a health promotion center. We measured hemoglobin levels, white matter hyperintensities (WMH) scales, lacunes, and microbleeds. Cortical thickness was automatically measured using surface based methods. Multivariate regression analyses were performed after controlling for possible confounders.
  
  
  RESULTS
  Decreased hemoglobin levels were not associated with the presence of WMH, lacunes, or microbleeds in women and men. Among women, decreased hemoglobin levels were associated with decreased cortical thickness in the frontal (Estimates, 95% confidence interval, -0.007, (-0.013, -0.001)), temporal (-0.010, (-0.018, -0.002)), parietal (-0.009, (-0.015, -0.003)), and occipital regions (-0.011, (-0.019, -0.003)). Among men, however, no associations were observed between hemoglobin levels and cortical thickness.
  
  
  CONCLUSIONS
  Our findings suggested that decreased hemoglobin levels affected cortical atrophy, but not increased CSVD, among women, although the association is modest. Given the paucity of modifiable risk factors for age-related cognitive decline, our results have important public health implications.
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Sang Eon
authors.initials: SE
authors.lastname: Park
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Hojeong
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Jeongmin
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Na Kyung
authors.initials: NK
authors.lastname: Lee
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Jung Won
authors.initials: JW
authors.lastname: Hwang
authors.affiliation: Department of Biomedical Engineering,Hanyang University,Seoul,South Korea.
authors.forename: Jin-ju
authors.initials: JJ
authors.lastname: Yang
authors.affiliation: Department of Neurology,Yonsei University College of Medicine,Seoul,South Korea.
authors.forename: Byoung Seok
authors.initials: BS
authors.lastname: Ye
authors.affiliation: Department of Neurology,Gangnam Severance Hospital,Yonsei University College of Medicine,Seoul,South Korea.
authors.forename: Hanna
authors.initials: H
authors.lastname: Cho
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Yeo Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Na-Yeon
authors.initials: NY
authors.lastname: Jung
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Tae Ok
authors.initials: TO
authors.lastname: Son
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Eun Bin
authors.initials: EB
authors.lastname: Cho
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Hyemin
authors.initials: H
authors.lastname: Jang
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Jang
authors.affiliation: Ajou University School of Medicine,Suwon,South Korea.
authors.forename: Chang Hyung
authors.initials: CH
authors.lastname: Hong
authors.affiliation: Department of Biomedical Engineering,Hanyang University,Seoul,South Korea.
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Lee
authors.affiliation: Center for Health Promotion,Samsung Medical Center,Seoul,South Korea.
authors.forename: Mira
authors.initials: M
authors.lastname: Kang
authors.affiliation: Center for Health Promotion,Samsung Medical Center,Seoul,South Korea.
authors.forename: Hee-Young
authors.initials: HY
authors.lastname: Shin
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Duk L
authors.initials: DL
authors.lastname: Na
authors.affiliation: Department of Neurology,Samsung Medical Center,Sungkyunkwan University School of Medicine,Seoul,South Korea.
authors.forename: Sang Won
authors.initials: SW
authors.lastname: Seo
mesh_terms: D000368:Aged; D001284:Atrophy / Q000473:pathology; D001927:Brain Diseases / Q000473:pathology*; D002540:Cerebral Cortex / Q000473:pathology*; D003071:Cognition; D005260:Female; D064368:Healthy Volunteers; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012044:Regression Analysis; D056910:Republic of Korea
chemical_list: D006454:Hemoglobins
keywords: anemia; cerebral small-vessel disease (CSVD); cortical thickness; dementia