Sun-sensitizing medications, sun exposure linked to cataract

Washington, June 15 : A new study has revealed that the use of medications that increase sensitivity to the sun, combined with exposure to sunlight, is associated with the risk of age-related cataract.

Sunlight and exposure to ultraviolet-B (UV-B) rays have been shown to be associated with cortical cataract, clouding or opacity occurring first on the outer edges of the lenses.

Some medications taken by mouth or by injection have been shown to increase sensitivity to the sun, causing signs and symptoms such as itching or rash on areas of the skin exposed to sunlight.

To determine if these medications also affect the association of sun exposure to cortical cataract, Barbara E. K. Klein, and colleagues at the University of Wisconsin, Madison, studied 4,926 individuals living in Beaver Dam, Wisconsin and first examined between 1988 and 1990.

Participants were interviewed about their residential history, which was used to construct a measure of their average annual exposure to ambient UV-B rays.

Interviewers also asked participants to bring their medications, and any sun-sensitizing drug—including diuretics, antidepressants, antibiotics and the pain reliever naproxen sodium.

An increasing percentage of study participants reported having taken these types of medications over a 15-year follow-up period (24.1 percent at the beginning of the study, compared with 44.8 percent at the 15-year follow-up). The overall incidence of cataract was not associated with their use or with exposure to sunlight.

However, after adjusting for age and sex, an interaction between sun-sensitizing medication use and UV-B exposure was associated with the development of cortical cataract.

The study has been reported online today that will appear in the August print issue of Archives of Ophthalmology, one of the JAMA/Archives journals.