Clinical Question: Do statins reduce the risk of cataracts?

Setting: Population-based

Study Design: Cohort (prospective)

Synopsis: These investigators analyzed data obtained from an observational, longitudinal study of age-related eye disease in Beaver Dam, Wis. A total of 1,299 adults with gradable photographs in both eyes underwent evaluation for nuclear cataracts, the most common type of age-related cataract, five years after the start of the study. Almost all (99 percent) of the population was non-Hispanic white. Individuals assessing outcomes were blinded to participant identity and drug use. The five-year incidence of nuclear cataract was 12.2 percent in statin users compared with 17.2 percent in nonusers (odds ratio = 0.55; 95% confidence interval, 0.36 to 0.84). The reduced incidence for statin users remained significant after controlling for age, sex, smoking, lipid level, and diabetes. The incidence of other types of cataracts, including cortical and posterior subcapsular, was not significantly reduced.

Bottom Line: Statin use is associated with a reduced incidence of nuclear cataracts, the most common type of age-related cataracts. However, this type of study design (prospective cohort study) does not prove a causal relationship between the use of statins and lower risk of developing cataracts. It is possible that other confounding variables (e.g., genetics or patient compliance) are causally related. (Level of Evidence: 2b)