title: Exploratory analysis of dietary intake and brain iron accumulation detected using magnetic resonance imaging in older individuals: the Lothian Birth Cohort 1936.
abstract: BACKGROUND
  Brain Iron Deposits (IDs) are associated with neurodegenerative diseases and impaired cognitive function in later life, but their cause is unknown. Animal studies have found evidence of relationships between dietary iron, calorie and cholesterol intake and brain iron accumulation.
  
  
  OBJECTIVE
  To investigate the relationship between iron, calorie, and cholesterol intake, blood indicators of iron status, and brain IDs in humans.
  
  
  METHODS
  Cohort of 1063 community-dwelling older individuals born in 1936 (mean age 72.7years, SD=0.7) with dietary information, results from blood sample analyses and brain imaging data contemporaneously in old age.
  
  
  METHODS
  Magnetic Resonance Imaging was used to assess regional volumes of brain IDs in basal ganglia, brainstem, white matter, thalamus, and cortex/border with the corticomedullary junction, using a fully automatic assessment procedure followed by individual checking/correction where necessary. Haemoglobin, red cell count, haematocrit, mean cell volume, ferritin and transferrin were obtained from blood samples and typical daily intake of iron, calories, and cholesterol were calculated from a validated food-frequency questionnaire.
  
  
  RESULTS
  Overall, 72.8% of the sample that had valid MRI (n=676) had brain IDs. The median total volume of IDs was 40mm3, inter-quartile range (IQR)=196. Basal ganglia IDs (median=35, IQR=159.5 mm3), were found in 70.6% of the sample. IDs in the brainstem were found in 12.9% of the sample, in the cortex in 1.9%, in the white matter in 6.1% and in the thalamus in 1.0%. The median daily intake of calories was 1808.5kcal (IQR=738.5), of cholesterol was 258.5mg (IQR=126.2) and of total iron was 11.7mg (IQR=5). Iron, calorie or cholesterol intake were not directly associated with brain IDs. However, caloric intake was associated with ferritin, an iron storage protein (p=0.01).
  
  
  CONCLUSIONS
  Our results suggest that overall caloric, iron and cholesterol intake are not associated with IDs in brains of healthy older individuals but caloric intake could be associated with iron storage. Further work is required to corroborate our findings on other samples and investigate the underlying mechanisms of brain iron accumulation.
authors.affiliation: Dr. Maria C. Valdés Hernández, Brain Research Imaging Centre, Department of Neuroimaging Sciences, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK. Telephone: +44-131-537-3093, Fax: +44-131-332-5150, E-mail: mvhernan@staffmail.ed.ac.uk.
authors.forename: M del C Valdés
authors.initials: Mdel C
authors.lastname: Hernández
authors.forename: J
authors.initials: J
authors.lastname: Allan
authors.forename: A
authors.initials: A
authors.lastname: Glatz
authors.forename: J
authors.initials: J
authors.lastname: Kyle
authors.forename: J
authors.initials: J
authors.lastname: Corley
authors.forename: C E
authors.initials: CE
authors.lastname: Brett
authors.forename: S Muñoz
authors.initials: SM
authors.lastname: Maniega
authors.forename: N A
authors.initials: NA
authors.lastname: Royle
authors.forename: M E
authors.initials: ME
authors.lastname: Bastin
authors.forename: J M
authors.initials: JM
authors.lastname: Starr
authors.forename: I J
authors.initials: IJ
authors.lastname: Deary
authors.forename: J M
authors.initials: JM
authors.lastname: Wardlaw
mesh_terms: D000368:Aged; D000375:Aging / Q000378:metabolism; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D002784:Cholesterol / Q000008:administration & dosage / Q000378:metabolism; D003071:Cognition / Q000502:physiology; D015331:Cohort Studies; D004032:Diet / Q000706:statistics & numerical data*; D002149:Energy Intake; D004906:Erythrocyte Count; D004909:Erythrocyte Indices; D005260:Female; D005293:Ferritins / Q000097:blood; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D019266:Iron, Dietary / Q000008:administration & dosage / Q000032:analysis* / Q000378:metabolism*; D008279:Magnetic Resonance Imaging; D008297:Male; D019636:Neurodegenerative Diseases; D059906:Neuroimaging; D011795:Surveys and Questionnaires; D014168:Transferrin / Q000032:analysis
chemical_list: D006454:Hemoglobins; D019266:Iron, Dietary; D014168:Transferrin; D005293:Ferritins; D002784:Cholesterol