Purchase this article with an account.
GR Gensler, RD Sperduto, BE K Klein, R Klein, EY ChewAREDS Research Group; The seven-year incidence and progression of cataract in the Age-Related Eye Disease Study (AREDS) . Invest. Ophthalmol. Vis. Sci. 2002;43(13):1908.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose:To describe the seven-year incidence and progression of cataract in AREDS. Methods:Participants in AREDS, followed for up to seven years, were randomized to receive daily tablets containing antioxidants, zinc, antioxidants plus zinc, or placebo. As no treatment significantly affected the development or progression of cataract, the entire cohort can provide data on the natural history of cataract. Lens status was assessed from photographs graded at a reading center. Nuclear opacity was graded by comparison with standard photos on a 6-unit severity scale; cortical and PSC opacities were assessed as percent involvement of the central lens. A cataract event included at least one of the following occurring in an eye without history of cataract surgery at baseline: a 1.5 unit increase in nuclear opacity, a 10% increase in area of cortical opacity, a 5% increase in area of posterior subcapsular (PSC) opacity, or cataract surgery. Participants were categorized as having "no cataract" at baseline if nuclear opacity score was 2 or less in both eyes, and there no was evidence of cortical or PSC opacity in either eye. The "no cataract" conditions could be analyzed jointly or separately. Participants were categorized as having "cataract" at baseline if the nuclear score was 4 or higher in at least one eye or area of cortical opacity was 5% or higher in at least one eye. PSC was excluded due to low prevalence of opacity. A repeated-measures logistic regression model adjusting for time was used to estimate progression to a cataract event. Results:4,596 participants had some follow-up and at least one natural lens at baseline, 1822 had no "nuclear" cataract, 2040 had no "cortical" cataract, and 3817 had no "PSC" cataract. Jointly, 915 participants had no cataract at baseline. The 7-year rate of progression, from opacity type absent to same type event, was 21% for nuclear, 12% for cortical, and 16% for PSC opacities. For participants with none of the three types of cataract at baseline, the 7-year rate of progression to any cataract event was 20%. The 7-year rate of progression to a nuclear event among the 513 participants with nuclear cataract in at least one eye at baseline was 43%; among the 452 with cortical cataract in at least one eye the rate of progression to a cortical event was 70%. Conclusion:Participants with «cataract» at baseline were far more likely to experience a lens event than participants with «no cataract».
This PDF is available to Subscribers Only