title: ASSOCIATIONS BETWEEN AGE-RELATED MACULAR DEGENERATION, OSTEOARTHRITIS AND RHEUMATOID ARTHRITIS: RECORD LINKAGE STUDY.
abstract: OBJECTIVE
  The epidemiologic relationship between age-related macular degeneration (AMD) and arthritis is unknown and has implications for understanding disease pathogenesis and treatment strategies.
  
  
  METHODS
  An AMD cohort of 245,912 people was constructed from English linked hospital episode statistics (1999-2011), principally comprising neovascular AMD patients undergoing anti-vascular endothelial growth factor therapy. We compared the AMD cohort with a reference cohort (2,134,771 people) for rates of subsequent osteoarthritis (OA) and rheumatoid arthritis. Osteoarthritis (2,032,472 people) and rheumatoid arthritis (261,232 people) cohorts were also constructed and compared with the reference cohort for rates of subsequent AMD.
  
  
  RESULTS
  Risk of arthritis after AMD was not elevated. The rate ratio for OA was 0.96 (95% confidence interval 0.95-0.97) and for rheumatoid arthritis was 0.98 (0.94-1.02). However, risk of AMD after arthritis was modestly raised. For OA, the rate ratio was 1.06 (1.04-1.08), but risk increased with longer OA duration, for example, 1.15 (1.08-1.23) for >10 years. For rheumatoid arthritis, the rate ratio was also modestly elevated at 1.15 (1.12-1.19).
  
  
  CONCLUSIONS
  Age-related macular degeneration and arthritis are degenerative aging conditions that share some disease mechanisms and extracellular matrix involvement. However, considering arthritis after AMD, they are not positively associated. By contrast, people with OA experience modestly increased AMD risk, perhaps owing to medical treatments for OA.
authors.affiliation: *Centre for Hearing and Vision Research, Institute of Human Development, Faculty of Medicine and Human Sciences, University of Manchester and Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom; and †Unit of Health-Care Epidemiology, Department of Public Health, University of Oxford, Oxford, United Kingdom.
authors.forename: Tiarnan D L
authors.initials: TD
authors.lastname: Keenan
authors.forename: Raph
authors.initials: R
authors.lastname: Goldacre
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Goldacre
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000453:epidemiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008268:Macular Degeneration / Q000453:epidemiology*; D008297:Male; D008498:Medical Record Linkage; D008875:Middle Aged; D010003:Osteoarthritis / Q000453:epidemiology*; D012307:Risk Factors; D006113:United Kingdom / Q000453:epidemiology