Purpose: To analyze the potential association between aspirin use and progression of age-related macular degeneration (AMD).
Design: Two prospective cohort studies within 2 controlled clinical trials of oral supplementation for age-related eye disease.
Participants: Age-Related Eye Disease Study (AREDS) participants 55 to 80 years of age and AREDS2 participants 50 to 85 years of age.
Methods: Propensity scores for aspirin use were calculated for AREDS and AREDS2 participants separately by logistic regression. Of the participants without late AMD (geographic atrophy [GA] or neovascular AMD) in either eye at study baseline, aspirin users were matched 1:1 with nonusers by propensity score (separately for AREDS and AREDS2). Proportional hazards regression was performed, adjusting for age, on the matched participants to evaluate associations between aspirin propensity score and progression to late AMD (and its subtypes).
Main outcome measures: Progression to late AMD on color fundus photographs, graded centrally.
Results: Of the 3734 eligible AREDS participants, 1049 (28.1%) were taking aspirin, and of the 2403 eligible AREDS2 participants, 1198 (49.9%) were taking aspirin. After matching by propensity score, the characteristics of the users and nonusers were similar in both studies. Of the 1950 matched AREDS participants and 1694 matched AREDS2 participants, over a median follow-up of 10.1 years and 5.0 years, respectively, the numbers who progressed to late AMD, GA, or neovascular AMD were 454 (23.3%), 345 (17.7%), and 278 (14.3%), respectively, in AREDS and 643 (38.0%), 402 (24.6%), and 341 (20.1%) in AREDS2. The hazard ratios of progression in quintile 5 (highest propensity for aspirin use) versus 1 (reference) were 1.17 (P = 0.35), 1.24 (0.25), and 0.95 (0.81), respectively, in AREDS and 1.26 (0.09), 1.46 (0.03), and 1.12 (0.58) in AREDS2. No significant association with progression to late AMD was observed for quintiles 2 through 5 for any of the 3 outcomes in either study.
Conclusions: Aspirin use was not associated significantly with progression to late AMD or its subtypes in either the AREDS or AREDS2. Patients with AMD need not avoid aspirin for this reason when its use is medically indicated.
Published by Elsevier Inc.