Abstract
Purpose :
To evaluate the effect of the geographic atrophy (GA) proximity to the center point of the fovea on visual acuity (VA)
Methods :
Color fundus photographs of participants enrolled in the Age-Related Eye Diseases Study 2 from annual study visits were graded for GA area and proximity to the center of the fovea. Mixed-model regression was performed with the VA as the primary outcome and with proximity to the center as the primary exposure. Models were also adjusted for: age, sex, education, smoking, pigmentary abnormalities and square root of the GA area. Eyes with incident GA were analyzed with the first occurrence considered year 0. The outcome of VA <20/40 was evaluated by using logistic regression. Analyses were performed at year 0 and 1 and 2 years after the initial GA.
Results :
There were 1067 eyes (862 participants) that progressed to GA at any time during the study. At all years, for eyes with GA in the center point of the fovea (CP), VA was significantly lower compared with GA located >1000µm from the CP (estimate (95% confidence limits), -13.5 (-16.9,-10.2), -14.8 (-20.2,-9.4), -18.6 (-28.4,-8.8) letters, for year 0 (1067 eyes), year 1 (670 eyes) and year 2 (461 eyes), respectively). At year 0, but not in later years, eyes with GA that was within 100µm of the CP also had lower VA (-6.3 (-11.2,-1.4)). The VA of eyes with GA located >100 and ≤1000 µm of the CP was not significantly different than for eyes with GA >1000 µm of the CP. Square root of GA area was significantly associated with lower VA (estimate, -5.4, -3.4, -4.4 letters/mm, for years 0, 1 and 2, respectively). Results for the outcome of VA<20/40 were similar. Eyes with GA in the CP were significantly more likely to have VA<20/40 than eyes with GA >1000 µm of the CP (odds ratio (OR): 4.2, 4.2, 8.5, for years 0, 1 and 2, respectively). The ORs for eyes with GA not in the CP were not significantly different than the OR for eyes with GA >1000 µm of the CP.
Conclusions :
VA was significantly affected by GA in the center point of the fovea and not so much by GA in the central zone but not in the CP. At all years VA was also greatly affected by total area of the GA.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.