title: Antioxidant vitamins and nuclear opacities: the longitudinal study of cataract.
abstract: OBJECTIVE
  The association of antioxidant nutrients and risk of nuclear opacification was evaluated in the Longitudinal Study of Cataract.
  
  
  METHODS
  Nutritional data were collected at baseline on the 764 participants, which included assessment of dietary intake, use of vitamin supplements, and plasma levels of vitamin E. Ophthalmologic and other data were collected at baseline and at yearly follow-up visits, including lens photographs, which were graded using the Lens Opacities Classification System III protocol.
  
  
  METHODS
  Analyses examined whether the nutritional factors at baseline were related to increases in nuclear opacification at follow-up. The MULCOX2 approach, an extension of the Cox regression model, was used. Results are presented as relative risks (RRs) and 95% confidence intervals.
  
  
  METHODS
  Intervention was not applicable.
  
  
  RESULTS
  The risk of nuclear opacification at follow-up was decreased in regular users of multivitamin supplements (RR = 0.69; 0.48-0.99), vitamin E supplements (RR = 0.43; 0.19-0.99), and in persons with higher plasma levels of vitamin E (RR = 0.58; 0.36-0.94).
  
  
  CONCLUSIONS
  In regular users of multivitamin supplements, the risk of nuclear opacification was reduced by one third; in regular users of vitamin E supplements and persons with higher plasma levels of vitamin E, the risk was reduced by approximately half. These results are similar to those obtained in our earlier case-control study. Because these data are based on observational studies only, the results are suggestive but inconclusive. The possible effect of nutritional supplements on the lens requires confirmation by ongoing clinical trials.
authors.affiliation: University Medical Center at Stony Brook, New York 11794-8036, USA.
authors.forename: M C
authors.initials: MC
authors.lastname: Leske
authors.forename: L T
authors.initials: LT
authors.lastname: Chylack
authors.forename: Q
authors.initials: Q
authors.lastname: He
authors.forename: S Y
authors.initials: SY
authors.lastname: Wu
authors.forename: E
authors.initials: E
authors.lastname: Schoenfeld
authors.forename: J
authors.initials: J
authors.lastname: Friend
authors.forename: J
authors.initials: J
authors.lastname: Wolfe
mesh_terms: D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage*; D016022:Case-Control Studies; D002386:Cataract / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D007907:Lens Nucleus, Crystalline; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D012307:Risk Factors; D014810:Vitamin E / Q000097:blood; D014815:Vitamins / Q000008:administration & dosage*
chemical_list: D000975:Antioxidants; D014815:Vitamins; D014810:Vitamin E