title: Nongenetic risk factors for neovascular age-related macular degeneration.
abstract: OBJECTIVE
  To create a risk model for neovascular age-related macular degeneration (nAMD) based on nongenetic factors.
  
  
  METHODS
  In this case-control study, 1459 individuals were included, 445 patients showed nAMD and 1014 were healthy controls. Participants were randomly assigned into a training set (containing two-thirds of individuals) and a validation set. Stepwise logistic regression analysis was performed for 25 environmental risk factors in the training set. The risk model with the remaining factors was then validated in the validation set using receiver operating characteristics (ROC) curve and Hosmer-Lemeshow-Test. Additionally, a genetic risk model including variants in the complement factor H gene (CFH, rs1061170) and the age-related maculopathy susceptibility 2 gene (ARMS2, rs10490924) was generated.
  
  
  RESULTS
  The environmental risk model with the factors age, alcohol use, allergy, education, sunlight exposure, fish consumption, and physical exercise showed an AUC of 0.80 (95% confidence interval [CI] 0.76-0.84) in the training set. Validation of the model showed adequate calibration (Hosmer-Lemeshow P = 0.81). The AUC for the genetic model was 0.77 (95% CI 0.730-0.808), for the combined environmental and genetic model 0.92 (95% CI 0.887-0.947).
  
  
  CONCLUSIONS
  Seven nongenetic factors are able to provide equivalent discrimination between nAMD patients and controls to genetic risk models. Most of them are modifiable and give the opportunity for counseling patients.
authors: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors: Tina
authors: T
authors: Ristau
authors: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors: Lebriz
authors: L
authors: Ersoy
authors: Institute of Medical Statistics, Informatics and Epidemiology, University of Cologne, Cologne, Germany.
authors: Moritz
authors: M
authors: Hahn
authors: Department of Ophthalmology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
authors: Anneke I
authors: AI
authors: den Hollander
authors: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors: Bernd
authors: B
authors: Kirchhof
authors: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors: Sandra
authors: S
authors: Liakopoulos
authors: Department of Ophthalmology, University Hospital of Cologne, Cologne, Germany.
authors: Sascha
authors: S
authors: Fauser
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D017242:Complement Factor H / Q000235:genetics; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D016015:Logistic Models; D008268:Macular Degeneration / Q000209:etiology* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000209:etiology* / Q000235:genetics; D011506:Proteins / Q000235:genetics; D012307:Risk Factors
chemical_list: C514392:ARMS2 protein, human; D011506:Proteins; D017242:Complement Factor H
keywords: age-related macular degeneration; nongenetic risk factor