Statins' Effects in Increasing Cataract Risk Appears Similar to that of Type 2 Diabetes, Reports Optometry and Vision Science

Newswise — Philadelphia, Pa. (August 7, 2012) - Patients using cholesterol-lowering statin drugs may be at increased risk of developing age-related cataracts, according to a study - “Age-related Cataract Is Associated with Type 2 Diabetes and Statin Use”, in the August issue of Optometry and Vision Science, official journal of the American Academy of Optometry. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.

While further research is needed to understand the true nature of the association, the additional risk of cataracts in statin users appears similar to that associated with type 2 diabetes, according to the study by Carolyn M. Machan, OD, and colleagues of University of Waterloo, Ont., Canada. Statins and Diabetes Both Increase Cataract RiskThe study included nearly 6,400 patients seen at the optometry clinic at the University of Waterloo in 2007-08. Of these, 452 patients had type 2 diabetes. Statin treatment and diabetes were evaluated as possible risk factors for age-related cataracts, controlling for other factors including sex, smoking, and high blood pressure.

Fifty-six percent of patients with type 2 diabetes were taking statins, compared to 16 percent of those without diabetes. Both diabetes and statin use were significantly associated with an increased rate of age-related cataracts.

With adjustment for other factors, diabetes was associated with an 82 percent increase in cataract risk and statin use with a 57 percent increase. Statistically, the increase in cataract risk associated with statins was similar to that associated with diabetes.

The associations differed for different types of cataracts. For one specific type long linked to diabetes (posterior subcapsular cataract), the association with diabetes was no longer significant after adjustment for statin treatment.

Despite the high rate of statin use among patients with diabetes, the two risk factors appeared independent of each other. At older ages, the risk of cataracts increased fastest in diabetic patients who took statins and slowest in nondiabetic patients who did not take statins. On average, cataracts developed 5.6 years earlier in diabetic patients who took statins, compared to nondiabetic patients who did not take statins.

Type 2 diabetes is a known risk factor for the development of age-related cataracts—a common vision problem caused by clouding of the crystalline lens of the eye. Studies in animals have shown a clear link between long-term treatment with statins (at high doses) and cataracts.

The new study suggests that statins may also be linked to cataracts in humans. The authors emphasize that the study can't prove that statins play any role in causing cataracts, but suggest that such a link is biologically plausible.

While further studies are needed, Dr Machan and colleagues emphasize that the known benefits of statin treatment for patients with type 2 diabetes probably outweigh any increased risk of cataracts. They believe their results will help to increase awareness of the risks of treatments for type 2 diabetes, and may encourage the development of alternative cholesterol-lowering drugs that are not associated with an increased risk of cataracts.

Anthony Adams, OD, PhD, Editor-in-Chief of Optometry and Vision Science, comments, "Considering the increase in the prevalence of diabetes and the corresponding increase in the use of statins, the authors feel these findings serve to encourage further research on the long-term effect of statins on the human crystalline lens."

To read the article “Age-related Cataract Is Associated with Type 2 Diabetes and Statin Use”, please visit http://journals.lww.com/optvissci/Fulltext/2012/08000/Age_Related_Cataract_Is_Associated_with_Type_2.12.aspx

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About Optometry and Vision ScienceOptometry and Vision Science, official journal of the American Academy of Optometry, is the most authoritative source for current developments in optometry, physiological optics, and vision science. This frequently cited monthly scientific journal has served primary eye care practitioners for more than 75 years, promoting vital interdisciplinary exchange among optometrists and vision scientists worldwide.

About the American Academy of OptometryFounded in 1922, the American Academy of Optometry is committed to promoting the art and science of vision care through lifelong learning. All members of the Academy are dedicated to the highest standards of optometric practice through clinical care, education or research.

About Lippincott Williams & Wilkins Lippincott Williams & Wilkins (LWW) is a leading international publisher of trusted content delivered in innovative ways to practitioners, professionals and students to learn new skills, stay current on their practice, and make important decisions to improve patient care and clinical outcomes. LWW is part of Wolters Kluwer Health, a leading global provider of information, business intelligence and point-of-care solutions for the healthcare industry. Wolters Kluwer Health is part of Wolters Kluwer, a market-leading global information services company with 2011 annual revenues of €3.4 billion ($4.7 billion).