Abstract
Purpose:
To describe the associations of drusen characteristics and retinal pigmentary abnormalities with the 10-year incidence of age-related macular degeneration (AMD) and visual acuity outcomes in the Age-Related Eye Disease Study (AREDS).
Methods:
Participants with varying AMD severity (n=4757) enrolled in a multi-centered randomized controlled clinical trial of antioxidant vitamins and minerals, median duration of 6.5 years. When the trial ended, 3549 of 4203 surviving participants were followed for 5 more years. The rates of progression to intermediate and advanced AMD were evaluated using annual color fundus photographs assessed centrally. Best-corrected visual acuity was measured at annual study visits..
Results:
The risk of progression to advanced AMD increased with age, female gender, smoking and increasing severity of drusen and pigmentary abnormalities. In the oldest participants with the most severe AMD/drusen status, 75% developed advanced AMD by 10 years. Similarly, the risk of progression from no AMD or early AMD to intermediate AMD was associated with severity of drusen at baseline. 71% of participants with bilateral medium sized drusen progressed to large drusen and 13% to advanced AMD in 10 years. Large drusen and pigmentary abnormalities remained important risk factors for progression, as demonstrated by the AREDS Simple Scale using presence or absence of drusen and pigmentary abnormalities to determine severity. Interestingly, the presence of large drusen within 1500 µm of the fovea also was an important predictor for development of advanced AMD. Median visual acuity at 10 years in eyes that had large drusen at baseline but never developed advanced AMD was 20/25; eyes that developed advanced AMD during follow-up had a median visual acuity of 20/200 at the 10-year visit, and also had a mean of 5 letter decrease from baseline at the annual visit prior to advanced AMD detection.
Conclusions:
Data collected in AREDS, prior to anti-VEGF inhibitor treatment, demonstrate the high risk of vision loss in persons who developed advanced AMD and are untreated. The natural history data and risk factors identified for progression to advanced AMD from long-term follow-up of AREDS participants may be helpful to investigators conducting research in clinic populations.
Keywords: 412 age-related macular degeneration •
504 drusen •
461 clinical (human) or epidemiologic studies: natural history