WEDNESDAY, Dec. 16, 2009 (HealthDay News) -- Injecting steroids into the eye may slow the progression of diabetes-related eye disease, but should not be counted on as a treatment at this time, researchers say.
Diabetic retinopathy, which can cause vision loss and blindness, occurs when new blood vessels form in the retina. The condition affects about 700,000 Americans, and 63,000 new cases develop each year, according to background information provided in the study. Control of blood glucose levels can help prevent the disease, and laser treatments can help lower the risk of vision loss, but researchers continue to search for new treatments.
In the new study, researchers tested different therapies on 840 eyes of 693 patients with macular edema, a leakage of fluid into part of the retina, which often occurs in retinopathy. The eyes received one of three treatments: photocoagulation -- a laser treatment that destroys blood vessels; a 1-milligram injection of the steroid triamcinolone acetonide directly into the eye as often as every four months; the same steroid regimen using a 4-milligram injection.
After two years, retinopathy had progressed in 31 percent of 330 eyes treated with photocoagulation, 29 percent of 256 eyes treated with 1-milligram doses of the steroid, and 21 percent of 254 eyes treated with 4-milligram doses of the steroid, the researchers reported in the December issue of the journal Archives of Ophthalmology.
"Use of this intravitreal [injected into the eye] corticosteroid preparation to reduce the likelihood of progression of retinopathy is not warranted at this time because of the increased risk of glaucoma and cataract associated with intravitreal steroid use," wrote Dr. Neil M. Bressler, of Johns Hopkins University School of Medicine in Baltimore, and colleagues in the Diabetic Retinopathy Clinical Research Network.
"Any treatment to be used routinely to prevent proliferative diabetic retinopathy likely needs to be relatively safe because the condition already can be treated successfully and safely with panretinal photocoagulation. Nevertheless, further investigation with regard to the role of pharmacotherapy for reduction of the incidence of progression of retinopathy appears to be warranted," they concluded.
The U.S. National Eye Institute has more about diabetic retinopathy.