title: Risk factors associated with incident cataracts and cataract surgery in the Age-related Eye Disease Study (AREDS): AREDS report number 32.
abstract: OBJECTIVE
  To investigate potential risk factors associated with incident nuclear, cortical, and posterior subcapsular (PSC) cataracts and cataract surgery in participants in the Age-Related Eye Disease Study (AREDS).
  
  
  METHODS
  Clinic-based prospective cohort study.
  
  
  METHODS
  Persons (n = 4425) 55 to 80 years of age enrolled in a controlled clinical trial of antioxidant vitamins and minerals, AREDS, for age-related macular degeneration and cataract.
  
  
  METHODS
  Lens photographs were graded centrally for nuclear, cortical, and PSC opacities using the AREDS system for classifying cataracts. Type-specific incident cataracts were defined as an increase in cataract grade from none or mild at baseline to a grade of moderate at follow-up, also with a grade of at least moderate at the final visit, or cataract surgery. Cox regression analyses were used to assess baseline risk factors associated with type-specific opacities and cataract surgery.
  
  
  METHODS
  Moderate cataract was defined as a grade of 4.0 or more for nuclear opacity, 10% or more involvement within the full visible lens for cortical opacity, and 5% or more involvement of the central 5-mm circle of the lens for PSC opacity. These were graded on baseline and annual lens photographs.
  
  
  RESULTS
  A clinic-based cohort of 4425 persons 55 to 80 years of age at baseline was followed up for an average of 9.8±2.4 years. The following associations were found: increasing age with increased risk of all types of cataract and cataract surgery; males with increased risk of PSC and decreased risk of cortical cataracts; nonwhite persons with increased risk of cortical cataract; hyperopia with decreased risk of PSC, nuclear cataract, and cataract surgery; Centrum (Wyeth Consumer Healthcare, Madison, NJ) use with decreased risk of nuclear cataract; diabetes with increased risk of cortical, PSC cataract, and cataract surgery; higher educational level with decreased risk of cortical cataract; and smoking with increased risk of cortical cataract and cataract surgery. Estrogen replacement therapy in female participants increased the risk of cataract surgery.
  
  
  CONCLUSIONS
  These findings largely are consistent with the results of previous studies, providing further evidence for possible modifiable risk factors for age-related cataract.
  
  
  BACKGROUND
  The author(s) have no proprietary or commercial interest in any materials discussed in this article.
authors.affiliation: Neurobiology, Neurodegeneration and Repair Laboratory, National Eye Institute/National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Jessica R
authors.initials: JR
authors.lastname: Chang
authors.forename: Euna
authors.initials: E
authors.lastname: Koo
authors.forename: Elvira
authors.initials: E
authors.lastname: Agrón
authors.forename: Joelle
authors.initials: J
authors.lastname: Hallak
authors.forename: Traci
authors.initials: T
authors.lastname: Clemons
authors.forename: Dimitri
authors.initials: D
authors.lastname: Azar
authors.forename: Robert D
authors.initials: RD
authors.lastname: Sperduto
authors.forename: Frederick L
authors.initials: FL
authors.lastname: Ferris
authors.forename: Emily Y
authors.initials: EY
authors.lastname: Chew
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D000975:Antioxidants / Q000008:administration & dosage*; D002386:Cataract / Q000145:classification / Q000453:epidemiology* / Q000503:physiopathology; D002387:Cataract Extraction / Q000706:statistics & numerical data*; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008268:Macular Degeneration / Q000503:physiopathology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014131:Trace Elements / Q000008:administration & dosage; D014792:Visual Acuity / Q000502:physiology; D014815:Vitamins / Q000008:administration & dosage
chemical_list: D000975:Antioxidants; D014131:Trace Elements; D014815:Vitamins