Long-Term Regular Use of Low-Dose Aspirin and Neovascular Age-Related Macular Degeneration: National Sample Cohort 2010-2015.

PURPOSE: The association between long-term cardioprotective aspirin use and neovascular age-related macular degeneration (AMD) is controversial. This study was undertaken to estimate the risk of neovascular AMD with long-term regular use of low-dose aspirin.

DESIGN: Retrospective population-based study, using a nationwide cohort from a variety of clinics and hospitals in South Korea.

PARTICIPANTS: Nonregular aspirin users and regular aspirin users under national health insurance, aged ≥45 years, who were followed from 2010 to 2015, were identified.

METHODS: Incidence per 10 000 person-years for neovascular AMD was estimated. Long-term regular use of low-dose aspirin was defined as sustained intake of ≤100 mg aspirin with ≥1044 days prescription between 2005 and 2009. Nonregular aspirin users included occasional users or nonusers. The analyses included a propensity score-adjusted analysis in a large, randomly selected, unmatched whole cohort (n = 482 613); propensity score-matched analysis in a matched cohort (n = 74 196); and maximally adjusted analysis in the unmatched whole cohort (n = 482 613).

MAIN OUTCOME MEASURES: Incidence of newly developed neovascular AMD using the registration code for intractable disease under national health insurance.

RESULTS: Incidence of neovascular AMD was 3.5 among nonregular aspirin users and 7.2 among regular aspirin users per 10 000 person-years in the unmatched whole cohort. However, propensity score-adjusted analyses revealed no association between aspirin use and neovascular AMD (adjusted hazard ratio [HR], 0.98; 95% confidence interval [CI], 0.73-1.30). Likewise, propensity score-matched analyses showed no association; incidences of neovascular AMD were 7.5 and 7.1 among nonregular aspirin users and regular aspirin users (crude HR, 0.94; 95% CI, 0.70-1.28), respectively. A maximally adjusted model, including age, sex, income, residential area, and history of 100 randomly selected types of generic drugs, showed no association (adjusted HR, 0.95; 95% CI, 0.71-1.28).

CONCLUSIONS: We found no association between long-term regular use of low-dose aspirin for 5 years and future incidence of neovascular AMD. Thus, this large-scale study suggests that regular, long-term use of low-dose aspirin appears to be safe with respect to the new development of neovascular AMD.