Statin use may be linked to increased cataract risk

Individuals taking statins are at higher risk of developing cataract at an earlier age than those not taking them, according to a study published in the August issue of Optometry and Vision Science, the official journal of the American Academy of Optometry.

“There is an association between statin use and the development of cataract in patients with and without diabetes,” said one of the study’s authors, Elizabeth Irving, OD, PhD, professor at the School of Optometry and Vision Science, University of Waterloo, Ontario, Canada.

The study included 6,397 patients seen at the optometry clinic at the University of Waterloo in 2007 to 2008. Of this group, 452 patients had type 2 diabetes. Statin use and type 2 diabetes were evaluated as possible risk factors for age-related cataracts, controlling for patient sex, smoking, and high blood pressure.

In patients aged >38 years, the prevalence of statin use was 56% for those with type 2 diabetes and 16% for those without diabetes, according to the study. Type 2 diabetes and statin use were significantly associated with an increased rate of age-related cataracts.

Type 2 diabetes was associated with a higher risk compared with cholesterol-lowering treatment (82% vs. 57%). The associations differ depending on the type of cataract. For example, the association of diabetes with a particular type of cataract, posterior subcapsular cataract, was not statistically significant when statin use was controlled for.

The 50% probability of cataract in statin users occurred at age 51.7 years for patients with type 2 diabetes and 54.9 years in patients without diabetes. In non-statin users, it was significantly later at age 55.1 for patients with type 2 diabetes and 57.3 years for patients without diabetes (P<.001).

“Diabetes, statin use, and cataract are all common in the population,” Irving said. “There would potentially be benefit to developing cholesterol-lowering drugs for which this association does not exist. There would also appear to be benefits to finding ways of reducing the numbers of persons needing to take these drugs.”