Abstract
Purpose: :
The purpose of this study was to model the trajectory of loss of acuity, contrast sensitivity, and visual fields in a population of older African-Americans and Caucasians, accounting for cataract surgery.
Methods: :
The SEE project is a population-based study of 2520 persons age 65 to 84 in Salisbury Maryland who have been followed over eight years. Four rounds of data were collected on visual acuity, contrast sensitivity, and integrated binocular visual fields. Mixed models with random effects were used to analyze trajectories of loss of acuity, contrast sensitivity, and visual fields over time.
Results: :
Adjusting for age, African -Americans started with worse visual acuity (LogMAR .12) and log contrast sensitivity (log CS=1.43) compared to Caucasians (LogMAR .08, log CS 1.53, p<.001 ). However, the average trajectory of loss over time was no different than that of Caucasians. Cataract surgery had a more pronounced improvement of acuity and contrast sensitivity for African Americans, who appeared to have surgery when vision function was worse. African Americans started with worse visual fields (51 points seen versus 59 for whites, p<.001), and had a worse average trajectory of field loss over time (-0.94 points per year), compared to Caucasians (-0.74 points per year, p=.06).
Conclusions: :
Once accounting for cataract surgery, there does not appear to be racial differences in the trajectory of visual acuity or contrast sensitivity loss over time; higher rates of glaucoma in African Americans may explain the disparity in loss of visual fields over time.
Keywords: clinical (human) or epidemiologic studies: natural history • contrast sensitivity • visual fields