Researchers Caution Disposable-Lens Users

People who wear disposable contact lenses are up to 14 times more likely to develop eye ulcers, which can lead to blindness, than wearers of non-disposable soft lenses, according to a study released Thursday.

But the wearers may be to blame, not the lenses. Dr. Terrence P. O’Brien of Johns Hopkins University in Baltimore said many wearers bring on problems by failing to properly care for disposable lenses and wearing them for too many hours.

“The problem is not necessarily one of the lenses,” said O’Brien, a specialist in eye infections at Johns Hopkins. “People have had a false sense of security, and they think these lenses have eliminated the problems.”

The study is the first to explore the risks associated with disposable lenses, which were introduced in 1988 in the hope that they would be safer than other soft lenses, the researchers said.

The study reported on 42 cases of eye ulcers associated with contact lens wear. It did not explore variations in wearing times and whether extended wear of disposable lenses might account for the elevated risk.

Among the patients studied, 19 wore disposable lenses, 14 wore soft lenses designed to be removed daily, five wore extended-wear soft lenses and four wore hard lenses, the researchers said.

Compared with users of daily-wear soft lenses, the most common type worn in the United States, users of disposable soft lenses had a 14-times greater risk of developing a type of eye ulcer called ulcerative keratitis, the researchers found.

The ulcers are usually caused by bacteria that yield readily to antibiotic treatment, but can cause vision-impairing scars and even blindness.

An estimated 2 million Americans wear disposable contact lenses and account for one in 12 of all contact lens wearers in the country, said the study, published in the November issue of the Archives of Ophthalmology.

The Contact Lens Council, which represents manufacturers, said the study was inconclusive and even the authors acknowledged “the actual risk of corneal ulcers associated with disposable contact lenses is very low.”

The American Academy of Ophthalmology said in a statement the new study is a “cause for caution, not for alarm.”