title: Non-Dietary Correlates and Determinants of Plasma Lutein and Zeaxanthin Concentrations in the Irish Population.
abstract: To investigate non-dietary correlates and determinants of plasma lutein (L) and zeaxanthin (Z) concentrations in The Irish Longitudinal Study on Ageing (TILDA) sample.
  
  
  
  Cross-sectional study.
  
  
  
  Community dwelling adults in the Republic of Ireland (ROI).
  
  
  
  3,681 participants aged 50 years and older.
  
  
  
  TILDA is a nationally representative prospective cohort study of community dwelling adults aged 50 years and over in the ROI. Demographic and health variables were collected during a face-to-face interview carried out in the home (n=8175), and a substantial proportion of these (n=5035; 62%) also attended a study visit in a health assessment centre. Blood samples collected at baseline (wave 1, the subject of the current study), were analysed for plasma concentrations of L and Z by reversed-phase high performance liquid chromatography, and macular pigment (MP) optical density was also measured (using customized heterochromatic flicker photometry).
  
  
  
  After excluding participants with eye disease, data from 3,681 participants were available for analysis. For this group of participants, plasma L and Z were inversely and significantly associated with body mass index (BMI), and were positively and significantly associated with MP, total cholesterol, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) (p<0.001, for all). Plasma L and Z were significantly lower in males, current smokers, participants reporting less physical exercise, and participants reporting lower levels of education (p<0.05, for all). Plasma L was significantly higher in participants reporting a family history of age-related macular degeneration (AMD) (p=0.001), and in the group of ≥75 years old (p<0.05). For each of these variables, the significant associations remained after controlling for other potential confounding variables.
  
  
  
  The findings of this large study indicate that plasma concentrations of L and Z were lower in association with indicators of a poor lifestyle (high BMI, tobacco use, and less physical exercise) and in association with lower education, indicating that modifying lifestyle in a positive way is likely to be reflected in higher concentrations of plasma carotenoids, with consequential and putative health benefits.
authors.affiliation: Rachel Moran, Macular Pigment Research Group, Nutrition Research Centre Ireland, Waterford Institute of Technology West Campus, Carriganore, Waterford, Ireland, Tel: +353 (0)51 306261; Email: rmoran@wit.ie.
authors.forename: R
authors.initials: R
authors.lastname: Moran
authors.forename: J M
authors.initials: JM
authors.lastname: Nolan
authors.forename: J
authors.initials: J
authors.lastname: Stack
authors.forename: A M
authors.initials: AM
authors.lastname: O'Halloran
authors.forename: J
authors.initials: J
authors.lastname: Feeney
authors.forename: K O
authors.initials: KO
authors.lastname: Akuffo
authors.forename: R A
authors.initials: RA
authors.lastname: Kenny
authors.forename: S
authors.initials: S
authors.lastname: Beatty
mesh_terms: D000368:Aged; D000375:Aging; D015992:Body Mass Index; D002338:Carotenoids / Q000097:blood*; D002784:Cholesterol / Q000097:blood; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D015444:Exercise; D005123:Eye / Q000378:metabolism; D005260:Female; D006304:Health Status; D006801:Humans; D007494:Ireland; D008075:Lipoproteins, HDL / Q000097:blood*; D008077:Lipoproteins, LDL / Q000097:blood*; D008137:Longitudinal Studies; D014975:Lutein / Q000097:blood*; D008268:Macular Degeneration / Q000097:blood; D065348:Macular Pigment / Q000032:analysis; D008297:Male; D008875:Middle Aged; D010783:Photometry; D011446:Prospective Studies; D012111:Residence Characteristics; D011795:Surveys and Questionnaires; D065146:Zeaxanthins / Q000097:blood*
chemical_list: D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D065348:Macular Pigment; D065146:Zeaxanthins; D002338:Carotenoids; D002784:Cholesterol; D014975:Lutein
keywords:  ageing; Lutein; lifestyle; nutrition; zeaxanthin