Objective: To investigate possible risk factors for age-related nuclear and cortical cataracts in participants in the Age-Related Eye Disease Study (AREDS).
Design: Case-control study.
Participants: Of the 4757 persons enrolled in AREDS, 4477 age 60 to 80 years are included in the study.
Main outcome measures: Slit-lamp lens photographs were used to classify participants into one of three nuclear opacity groups (moderate nuclear, mild nuclear, and controls), ignoring cortical opacities. Retroillumination lens photographs were used to classify participants into one of three cortical opacity groups (moderate cortical, mild cortical, and controls), ignoring nuclear opacities.
Results: Persons with moderate nuclear opacities were more likely to be female, nonwhite, and smokers and to have large drusen. Moderate nuclear opacities were less common in persons with higher educational status, a history of diabetes, and among those taking nonsteroidal antiinflammatory drugs. Moderate cortical opacities were associated with dark iris color, large drusen, weight change, and, at a borderline level of significance, higher levels of sunlight exposure and use of thyroid hormones. Moderate cortical opacities were less common in persons with higher educational status.
Conclusion: Consistent findings have now been reported across many studies for gender, educational status, sunlight exposure, and smoking. Our findings that use of nonsteroidal antiinflammatory drugs is inversely associated with nuclear cataract and that dark iris color and use of thyroid hormones may increase cortical cataract risk are less well substantiated and require further investigation.