title: Clinical characteristics of familial and sporadic age-related macular degeneration: differences and similarities.
abstract: OBJECTIVE
  We describe the differences and similarities in clinical characteristics and phenotype of familial and sporadic patients with age-related macular degeneration (AMD).
  
  
  METHODS
  We evaluated data of 1828 AMD patients and 1715 controls enrolled in the European Genetic Database. All subjects underwent ophthalmologic examination, including visual acuity testing and fundus photography. Images were graded and fundus photographs were used for automatic drusen quantification by a machine learning algorithm. Data on disease characteristics, family history, medical history, and lifestyle habits were obtained by a questionnaire.
  
  
  RESULTS
  The age at first symptoms was significantly lower in AMD patients with a positive family history (68.5 years) than in those with no family history (71.6 years, P = 1.9 × 10(-5)). Risk factors identified in sporadic and familial subjects were increasing age (odds ratio [OR], 1.08 per year; P = 3.0 × 10(-51), and OR, 1.15; P = 5.3 × 10(-36), respectively) and smoking (OR, 1.01 per pack year; P = 1.1 × 10(-6) and OR, 1.02; P = 0.005). Physical activity and daily red meat consumption were significantly associated with AMD in sporadic subjects only (OR, 0.49; P = 3.7 × 10(-10) and OR, 1.81; P = 0.001). With regard to the phenotype, geographic atrophy and cuticular drusen were significantly more prevalent in familial AMD (17.5% and 21.7%, respectively) compared to sporadic AMD (9.8% and 12.1%).
  
  
  CONCLUSIONS
  Familial AMD patients become symptomatic at a younger age. The higher prevalence of geographic atrophy and cuticular drusen in the familial AMD cases may be explained by the contribution of additional genetic factors segregating within families.
authors.affiliation: Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Nicole T M
authors.initials: NT
authors.lastname: Saksens
authors.affiliation: Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Eveline
authors.initials: E
authors.lastname: Kersten
authors.affiliation: Department of Epidemiology, Biostatistics, and Health Technology Assessment, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Joannes M M
authors.initials: JM
authors.lastname: Groenewoud
authors.affiliation: Diagnostic Image Analysis Group, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Mark J J P
authors.initials: MJ
authors.lastname: van Grinsven
authors.affiliation: Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Johannes P H
authors.initials: JP
authors.lastname: van de Ven
authors.affiliation: Diagnostic Image Analysis Group, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Clara I
authors.initials: CI
authors.lastname: Sánchez
authors.affiliation: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors.forename: Tina
authors.initials: T
authors.lastname: Schick
authors.affiliation: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors.forename: Sascha
authors.initials: S
authors.lastname: Fauser
authors.affiliation: Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Anneke I
authors.initials: AI
authors.lastname: den Hollander
authors.affiliation: Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Carel B
authors.initials: CB
authors.lastname: Hoyng
authors.affiliation: Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands Department of Ophthalmology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Camiel J F
authors.initials: CJ
authors.lastname: Boon
mesh_terms: D017677:Age Distribution; D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D008266:Macula Lutea / Q000473:pathology*; D008268:Macular Degeneration / Q000175:diagnosis* / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D016017:Odds Ratio; D015995:Prevalence; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D011795:Surveys and Questionnaires
keywords: AMD; clinical characteristics; family history