The active ingredients in a broad range of medications may make a person more vulnerable to age-related cataracts, suggest data from a long-term study (Arch Ophthalmol. 2010 Jun 14, published online ahead of print).
Previous research has shown a connection between sunlight and ultraviolet B (UVB) exposures and cortical cataract, a common lens opacity in adults. The active ingredients in several medications—such as furosemide, glyburide, amitriptyline, tetracycline, ciprofloxacin, amiodarone, and naproxen—are sun-sensitizing, causing skin exposed to the sun to become itchy or develop rashes. Researchers looked at the relationship between age-related cataracts and the use of sun-sensitizing agents included on a list compiled by various agencies.
The researchers evaluated the cumulative incidence of cortical cataract using data from 2,998 residents of Beaver Dam, Wisc. The men and women were aged 43 to 84 years when the census was performed.
Sun-sensitizing drugs were used by 24.1% of the participants at baseline and 44.8% at the 15-year follow-up. Although overall incidence of cataract was not associated with use of these agents or the level of sunlight exposure, an interaction between sun-sensitizing medication use, UVB exposure, and the development of cortical cataract was noted. The results stood even when investigators controlled for the presence of diabetes, history of heavy drinking, and hat or sunglasses use.
“The effect seems to be specific to cortical cataract, the cataract type that has been found in some cross-sectional investigations to be associated with UVB exposure,” the authors wrote. It was also noted that the specific mechanism for the interaction is unclear, and more research in other populations is needed.
In a related investigation, data from the Beaver Dam Offspring Study indicated that early age-related macular degeneration (AMD) is uncommon before age 55 years, but the risk increases with age thereafter. The early AMD is related to such modifiable risk factors as smoking and low levels of HDL. (Arch Ophthalmol. 2010;128:750-758). Another report in the same issue (pp. 738-749) supports previous evidence suggesting that women who eat foods rich in a variety of vitamins and minerals may help delay the onset of nuclear cataract, the most common type of cataract to occur in the United States, usually in women.