Low-dose aspirin and risk of cataract and subtypes in a randomized trial of U.S. physicians.
Christen WG, Manson JE, Glynn RJ, Ajani UA, Schaumberg DA, Sperduto RD, Buring JE, Hennekens CH.
Division of Preventive Medicine, Harvard Medical School, Boston, MA, USA.
PURPOSE: To examine whether low-dose aspirin (325 mg on alternate days) reduces the risk of age-related cataract and subtypes. This report extends previous findings, including both subtypes and additional newly identified incident cases since the earlier report. METHODS: All 20,979 participants in the Physicians' Health Study, a randomized trial of aspirin and beta-carotene among U.S. male physicians age 40-84 in 1982, who did not report cataract at baseline were included. Average follow-up was five years. The main outcome measure was incident, age-related cataract responsible for a reduction in best-corrected visual acuity to 20/30 or worse, based on self-report confirmed by medical record review. RESULTS: 501 age-related cataracts were diagnosed during follow-up, including 416 with nuclear sclerosis and 212 with a posterior subcapsular component; 318 cataracts progressed to surgical extraction. Overall, there were 245 cataracts in the aspirin group and 256 in the placebo group (relative risk [RR], 0.94; 95% confidence interval [CI], 0.79 to 1.13; P = 0.52). Cataract extractions were 19% less frequent in the aspirin than in the placebo group (RR, 0.81; 95% CI, 0.65 to 1.01; P = 0.06). In subgroup analyses of subtypes, aspirin takers had a lower risk of posterior subcapsular cataract (RR, 0.74; 95% CI, 0.57 to 0.98; P = 0.03) but not nuclear sclerosis (RR, 0.96; 95% CI, 0.79 to 1.16; P = 0.65) cataract. CONCLUSIONS: Overall, these randomized trial data tend to exclude a large benefit of five years of low-dose aspirin therapy on cataract development and extraction. The data are compatible with a modest benefit on cataract extraction for this duration of aspirin therapy. Subgroup analyses raise the possibility of a modest, but potentially important, protective effect of aspirin on posterior subcapsular cataract, a particularly disabling subtype.
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PMID: 9805346 [PubMed - indexed for MEDLINE]