Aspirin use and risk of cataract in posttrial follow-up of physicians' health study I

Background: In Physicians' Health Study I, randomized trial results indicated no major beneficial effect of 5 years of low-dose aspirin treatment on total cataract (relative risk [RR], 0.94; 95% confidence interval [CI], 0.79-1.13) or cataract extraction (RR, 0.81; 95% CI, 0.65-1.01) during the period of treatment. Objective: To examine the effect of assigned aspirin treatment and posttrial, self-selected aspirin use on the risk of age-related cataract over the 15 years of follow-up of Physicians' Health Study I. Methods: Participants were 20 968 US male physicians enrolled in Physicians' Health Study I who did not report cataract at baseline. At 7 years, after termination of the randomized aspirin component of the trial, self-selected aspirin use was computed from annual questionnaires. The main outcome measures were age-related cataract and extraction of age-related cataract, defined as an incident, age-related lens opacity responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-report confirmed by medical record review. Results: During a median of 14.9 years of follow-up, there were 2081 cataracts and 1198 cataract extractions. Overall, the age- and beta carotene-adjusted RR of cataract in men assigned to aspirin compared with those assigned to placebo was 1.09 (95% CI, 1.00-1.18). For cataract extraction, the RR was 1.09 (95% CI, 0.98-1.22). During a median posttrial follow-up of 7.9 years, a total of 1225 incident cataracts and 635 cataract extractions were documented. The multivariate RR of cataract in men who reported using aspirin frequently (greater than or equal to 180 days per year) at 1 years compared with nonusers (0-13 days per year) was 1.20 (95% CI, 1.03-1.40). For cataract extraction, the multivariate RR was 1.22 (95% CI, 0.98-1.51). Results for diagnosis and extraction of cataract subtypes were similar. Conclusions: Analyses based on randomized aspirin assignment indicated no long-term benefit of 5 years of low-dose aspirin treatment on total cataract or cataract extraction. Posttrial, observational data also indicated no decreased risk of cataract in aspirin users and suggested a small increased risk of cataract in aspirin users. Further randomized trial data to investigate the effect of longer term treatment with low-dose aspirin are being collected as part of the ongoing Women's Health Study, a randomized trial of low-dose aspirin and vitamin E among 39 876 apparently healthy, postmenopausal US female health professionals.