Beta-Blockers Tied to Higher Cataract Risk

July 24 -- THURSDAY, July 23 (HealthDay News) -- Australian researchers are reporting a possible link between widely used beta-blocker drugs and an increased risk of cataracts.

Beta-blockers are used in pill form to reduce high blood pressure and are also applied to the eye to treat glaucoma, a potentially blinding eye disease. The study found an association between both forms of beta-blocker therapy and accelerated cataract formation and a need for cataract surgery, according to the report published July 23 in the British Journal of Ophthalmology by researchers at the Centre for Vision Research at Westmead Hospital in Sydney.

The researchers tracked almost 3,700 Australians aged 49 or older for 10 years, looking at a variety of risk factors for cataract, a condition in which clouding of the lens of the eye reduces vision.

The association with beta-blocker use was seen after taking into account such known risk factors as smoking and steroid use.

The study found a 45 percent increased incidence of cataract formation and a 61 percent higher incidence of cataract surgery among people treated with beta-blockers, either for glaucoma or high blood pressure.

A "possible" association between use of a different class of high blood pressure drugs, calcium-channel blockers, and cataract surgery was seen in the study, but no such association was seen for all other drugs for high blood pressure.

The report adds weight to an existing theory of a link between beta-blockers and cataracts, said Dr. Donald L. Budenz, professor of ophthalmology and associate medical director of the University of Miami Bascom Palmer Eye Institute. But it should not affect use of the drugs for either glaucoma or high blood pressure, he said.

Like other forms of glaucoma treatment, topical beta-blocker therapy is designed to reduce the amount of aqueous humor, the fluid in the interior of the eye. Increased fluid pressure in the eye is believed to cause the damage done in glaucoma, in which the optic nerve deteriorates progressively, Budenz said.