title: Measurement of macular pigment optical density among healthy Chinese people and patients with early-stage age-related macular degeneration.
abstract: OBJECTIVE
  To measure the macular pigment optical density (MPOD) in healthy Chinese people and patients with early age-related macular degeneration (AMD).
  
  
  METHODS
  Cross-sectional population based study. Demographic and lifestyle characteristics were ascertained by questionnaire. A food frequency questionnaire was completed for all participants. Participants underwent general physical and ophthalmic examinations and MPOD was measured by heterochromatic flicker photometry. Foveal architecture was measured by optical coherence tomography.
  
  
  RESULTS
  MPOD of 225 participants (122 healthy and 103 early AMD) was 0.48±0.18. Patients with early AMD (0.52±0.19) tended to have higher MPOD levels than healthy people (0.47±0.17), but the difference was not statistically significant (P=0.06). Participants with carrot or corn oil intake every week tended to have higher levels of MPOD (P=0.002 and 0.008 respectively) while those with corn intake had relatively lower level of MPOD (P=0.01). MPOD increased with the center foveal thickness (P=0.01).
  
  
  CONCLUSIONS
  Our findings show that there is no statistically significant association between MPOD and early AMD in the studied population. MPOD is related to center foveal thickness and diets would influence MPOD levels.
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Xue-Tao
authors.initials: XT
authors.lastname: Ren
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Gu
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Han
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Jun-Yan
authors.initials: JY
authors.lastname: Zhang
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Li
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Xiu-Fen
authors.initials: XF
authors.lastname: Yang
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.affiliation: Sekwa Eye Hospital, Beijing 100088, China.
authors.forename: Torkel
authors.initials: T
authors.lastname: Snellingen
authors.affiliation: Department of Ophthalmology, the First Hospital of Tsinghua University, Beijing 100016, China.
authors.forename: Xi-Pu
authors.initials: XP
authors.lastname: Liu
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Ning-Li
authors.initials: NL
authors.lastname: Wang
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing 100730, China.
authors.forename: Ning-Pu
authors.initials: NP
authors.lastname: Liu
keywords: age-related macular degeneration; diets; foveal architecture; macular pigment optical density