| July 1, 2008
Diabetes Drug May Slow Eye Disease
The medication rosiglitazone may slow the progression of eye disease in diabetes patients, according to new research from the Jules Stein Eye Institute at the University of California, Los Angeles.
Specifically, researchers found that patients who took the drug were less likely to develop proliferative diabetic retinopathy or to experience reductions in visual acuity (sharpness). But they are not recommending the drug's use until further studies are done.
In proliferative diabetic retinopathy, existing blood vessels in the retina are blocked or damaged, resulting in the formation of new, tiny blood vessels. The condition is one of the leading causes of severe vision loss among working-age Americans, and there are few effective therapies to slow its progression.
In this study, researchers compared 124 diabetes patients who took rosiglitazone and 158 diabetes patients who didn't take the drug or a similar medication. At the start of the study, 14 eyes of the people in the rosiglitazone group (9.3 percent) and 24 eyes of people in the control group (9.3 percent) had severe non-proliferative diabetic retinopathy, an earlier stage of proliferative diabetic retinopathy.
Of the patients with severe non-proliferative diabetic retinopathy, 7.7 percent of those in the rosiglitazone group and 29.2 percent of those in the control group progressed to proliferative diabetic retinopathy within one year. After three years, 19.2 percent of the rosiglitazone group and 47.4 percent of the control group had progressed to proliferative diabetic retinopathy. That works out to a 59.5 percent reduced risk for those taking the drug.
The study also found that 0.5 percent of the rosiglitazone group and 14.5 percent of the control group experienced a loss of visual acuity of at least three lines on the vision chart during an average of 2.8 years of follow-up.
The study is published in the June issue of the Journal Archives of Ophthalmology.
Rosiglitazone may delay progression of retinopathy by reducing formation of new blood vessels, the researchers said.
"However, because this study does not rigorously prove that rosiglitazone either reduces the incidence of proliferative diabetic retinopathy or prevents loss of visual acuity, and because there may be adverse effects from therapy, rosiglitazone treatment of patients with diabetes specifically to reduce these ophthalmic complications is not advocated at this time," they wrote.
Rosiglitazone can cause such adverse effects as fluid build-up, abnormal liver function test, and worsening of congestive heart failure.
"Determination of the full efficacy and clinical role of rosiglitazone in the treatment of proliferative diabetic retinopathy and other angiogenic conditions awaits confirmation of risks and benefits and possibly large-scale definitive studies," the researchers concluded.
Source: JAMA/Archives journals, news release, June 9, 2008
Author: Robert Preidt
Source: http://www.medicinenet.com/script/main/art.asp?articlekey=90127
Comment:
Diabetic retinopathy, is the most common cause of blindness in the USA for persons under age 65. It is characterized by development of new and abnormal blood vessels on the retina, on or near the optic nerve, which could block the optic nerve and also carry the risk of bleeding causing vitreous hemorrhage and in some cases detachment of the retina. Currently available treatment is laser therapy and in complicated cases it has to be treated as an emergency eye operation. Although according to the limited study mentioned in this article indicates that usage of rosiglitazone (trade name-Avandia) may delay the progression of retinopathy, the authors emphatically point out that due to dangerous side effects associated with Avandia, this should not be considered a standard treatment yet. Recently Avandia has been under scrutiny because it is found to significantly increase the risk of heart attacks, congestive heart failure, abnormal liver function tests and bone fractures.
Dr. Rath's research and clinical trials in diabetes patients have indicated that use of a specific synergistic nutrient combination effectively reduces the blood sugar level, and Hemoglobin A1c, which is an indicator of long-term control of blood sugar. Additionally it was also noticed in these trials that complications of diabetes such as reduced blood flow to the affected limbs could also be improved.
You can read more about Dr. Rath's explanation of how nutrients could improve diabetes in his book "Why animals don't get heart attacks...but people do!". Results of our clinical trials can be viewed at www.drrathresearch.org
|
|
