Researchers have found that immediately treating people who have early stage glaucoma can delay progression of the disease. This finding supports the medical community's emerging consensus that treatment to lower pressure inside the eye can slow glaucoma damage and subsequent vision loss. These results are reported in the October 2002 issue of Archives of Ophthalmology.

Scientists found that immediate treatment of newly-discovered primary open-angle glaucoma, the most common form of glaucoma and one of the nation's leading causes of vision loss, led to a slower rate of disease progression. The findings from this study reinforce accumulating medical evidence that lowering eye pressure in glaucoma's early stages slows progression of the disease.

"These results strongly support the body of evidence suggesting that immediate treatment of early stage, open-angle glaucoma will slow the disease progression," said Paul Sieving, M.D., Ph.D., director of the National Eye Institute (NEI), one of the Federal government's National Institutes of Health and co-sponsor of the study. "Unfortunately, glaucoma has no early warning signs, and many affected patients are unaware they have the disease until it has advanced. Once people have lost vision from glaucoma, it cannot be regained. However, early detection and timely treatment would help to save the vision of thousands of people each year."

Dr. Sieving also notes that the study results provide important new medical knowledge on the course of the disease, both among treated and untreated patients. "Because most people are treated for glaucoma as soon as they are diagnosed, little is known about the natural history of the disease," he said. "Future reports from the study will add further important information on glaucoma progression and its risk factors."

The study -- called the Early Manifest Glaucoma Trial -- followed 255 patients, aged 50-80 years, with early stage glaucoma in at least one eye. Most patients were identified in a population screening. The average age of the patients at the beginning of the study was 68 years. One group (129 patients) was treated immediately with medicines and laser to lower eye pressure, and the other group (126 patients) -- the control group -- was left untreated. Both groups were followed carefully and monitored every three months for early signs of advancing disease, using indicators that are extremely sensitive for detecting glaucoma progression. Any patient in the control group whose glaucoma progressed was immediately offered treatment.

After six years of followup, scientists found that progression was less frequent in the treated group (45 percent) than in the control group (62 percent), and occurred significantly later in treated patients. Treatment effects were also evident in patients with different characteristics, such as age, initial eye pressure levels, and degree of glaucoma damage. In the treated group, eye pressure was lowered by an average of 25 percent.

The study was a collaborative effort involving the University of Lund, Sweden, with centers in Malmö, Helsingborg, and Lund, Sweden, as well as Stony Brook University, Stony Brook, New York.

These results should be put into perspective, according to Anders Heijl, M.D., Ph.D., chairman of the Department of Ophthalmology at Sweden's Malmö University Hospital and first author of the report. "Although the study closely checked for possible glaucoma progression, many of the patients remained stable over time, even those in the control group," Dr. Heijl said. "On the other hand, despite the clear effect of treatment, glaucoma progressed in as many as 30 percent of treated patients after four years."