title: Five heavy metallic elements and age-related macular degeneration: Korean National Health and Nutrition Examination Survey, 2008-2011.
abstract: OBJECTIVE
  To investigate the association between age-related macular degeneration (AMD) and 5 heavy metallic elements (lead, mercury, cadmium, manganese, and zinc).
  
  
  METHODS
  A cross-sectional study using a complex, stratified, multistage, probability cluster survey.
  
  
  METHODS
  Participants of the Korean National Health and Nutrition Examination Survey from 2008 to 2011.
  
  
  METHODS
  Using a standardized protocol, AMD was determined by fundus photograph grading. Blood concentrations of lead, mercury, cadmium, manganese, and zinc were measured. Associations between AMD and these 5 elements were estimated using logistic regression analyses (LRAs). The distributions of the 5 metallic elements in blood were analyzed, and the same set of LRAs estimating the association between AMD and logarithmic-transformed blood concentrations of the 5 elements were also conducted.
  
  
  METHODS
  Association between AMD and 5 heavy metals.
  
  
  RESULTS
  Lead was positively associated with both early AMD and late AMD in all LRAs. Mercury and cadmium also had a positive association with late AMD in all LRAs, but not with early AMD. In contrast, manganese and zinc had an inverse association with late AMD in all LRAs. Manganese and zinc were not associated with early AMD. Using logarithmic-transformed blood concentrations for each metallic element, the LRAs showed similar results compared with those of the LRAs using nontransformed blood concentrations, despite the skewed distribution of these metallic elements in the blood.
  
  
  CONCLUSIONS
  This study suggests that the toxic heavy metals (lead, mercury, and cadmium) may negatively influence late AMD, whereas essential heavy metals (manganese and zinc) may favorably influence late AMD. Lead may widely affect the pathogenesis of both early and late AMD.
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Sang Jun
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Medical Research Collaborating Center, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Ju Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
authors.forename: Se Joon
authors.initials: SJ
authors.lastname: Woo
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Se Woong
authors.initials: SW
authors.lastname: Kang
authors.affiliation: Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea. Electronic address: jiani4@snu.ac.kr.
authors.forename: Kyu Hyung
authors.initials: KH
authors.lastname: Park
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D002104:Cadmium / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D000075322:Heavy Metal Poisoning; D006801:Humans; D007854:Lead / Q000097:blood; D008268:Macular Degeneration / Q000097:blood / Q000139:chemically induced*; D008297:Male; D008345:Manganese / Q000097:blood; D008628:Mercury / Q000097:blood; D019216:Metals, Heavy / Q000009:adverse effects / Q000097:blood*; D008875:Middle Aged; D009749:Nutrition Surveys; D011041:Poisoning; D056910:Republic of Korea; D013054:Spectrophotometry, Atomic; D015032:Zinc / Q000097:blood
chemical_list: D019216:Metals, Heavy; D002104:Cadmium; D007854:Lead; D008345:Manganese; D008628:Mercury; D015032:Zinc