title: Cross Sectional and Longitudinal Associations between Cardiovascular Risk Factors and Age Related Macular Degeneration in the EPIC-Norfolk Eye Study.
abstract: OBJECTIVE
  To examine the cross sectional and longitudinal relationship between cardiovascular risk factors and age-related macular degeneration (AMD) in a large British cohort study.
  
  
  METHODS
  The EPIC Norfolk Eye study is nested in a larger prospective cohort study. Data on cardiovascular risk factors were collected at baseline (1993-1997) and follow up (2006-2011) via clinical examination, validated lifestyle questionnaires and serum blood samples. AMD was ascertained using standardised grading of fundus photographs at the follow up. Logistic regression was used to examine associations between baseline and follow up risk factors with AMD.
  
  
  RESULTS
  5,344 pairs (62.0% of total 8623) of fundus photographs were of sufficient quality for grading of AMD in participants with mean age of 67.4 years old (range 44-91) at diagnosis. There were 28 cases of late AMD (0.5%, 95% confidence interval (CI)=0.3-0.8%) and 645 cases of early AMD (12.1%, 95%CI=11.2-13.0.%). In multivariable analysis, older people with higher levels of baseline high density lipoprotein- cholesterol (HDL-C ) and C-reactive protein (CRP) were more likely to have any signs of AMD, after adjusting for sex, education, smoking, and systolic blood pressure. In cross sectional analysis, only older age and higher HDL were significantly associated with AMD.
  
  
  CONCLUSIONS
  We have found that older age and higher levels of CRP and HDL-C were associated with increased odds of AMD in this population in the longitudinal analysis, but older age and HDL-C, not CRP was significantly associated with AMD in the cross sectional analysis. The prevalence of AMD in this cohort was low compared to other cohorts in Europe, the US and Australia, and probably reflects the some selection biases in follow up participation as well as the low rate of smoking among our healthy participants.
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom; NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Jennifer L Y
authors.initials: JL
authors.lastname: Yip
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom; NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Khawaja
authors.affiliation: NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Michelle P Y
authors.initials: MP
authors.lastname: Chan
authors.affiliation: Department of Ophthalmology, Norfolk and Norwich University Hospital, Norwich, United Kingdom.
authors.forename: David C
authors.initials: DC
authors.lastname: Broadway
authors.affiliation: NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Tunde
authors.initials: T
authors.lastname: Peto
authors.affiliation: NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Adnan
authors.initials: A
authors.lastname: Tufail
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Robert
authors.initials: R
authors.lastname: Luben
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Shabina
authors.initials: S
authors.lastname: Hayat
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Amit
authors.initials: A
authors.lastname: Bhaniani
authors.affiliation: MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge, United Kingdom.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: Wareham
authors.affiliation: Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Kay-Tee
authors.initials: KT
authors.lastname: Khaw
authors.affiliation: NIHR Biomedical Research Centre at Moorfields Eye Hospital and UCL Institute of Ophthalmology, London, United Kingdom.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Foster
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002318:Cardiovascular Diseases / Q000150:complications* / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D004739:England / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008268:Macular Degeneration / Q000150:complications* / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012307:Risk Factors