Age-Related Eye Disease Study (AREDS)
To assess the clinical course, prognosis, and risk factors of age-related macular degeneration (AMD) and cataract.
To evaluate, in randomized clinical trials, the effects of pharmacologic doses of (1) antioxidants and zinc on the progression of AMD and (2) antioxidants on the development and progression of lens opacities.
|Macular Degeneration Cataract Lens Opacities||Dietary Supplement: Antioxidants Dietary Supplement: Zinc Dietary Supplement: Antioxidants and zinc||Phase 3|
|Study Design:||Allocation: Randomized
Intervention Model: Factorial Assignment
Masking: Double Blind (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
|Official Title:||Age-Related Eye Disease Study (AREDS)|
- Progression of age-related macular degeneration
- Progression of lens opacity (cataract)
|Study Start Date:||September 1990|
|Study Completion Date:||December 2006|
|Primary Completion Date:||October 2001 (Final data collection date for primary outcome measure)|
Dietary Supplement: Antioxidants
500 milligrams vitamin C; 400 IUs vitamin E; 15 milligrams beta-carotene
Dietary Supplement: Zinc
80 milligrams zinc oxide; 2 milligrams of cupric oxide
Antioxidants and zinc
Dietary Supplement: Antioxidants and zinc
500 milligrams vitamin C; 400 IUs vitamin E; 15 milligrams beta-carotene; 80 milligrams zinc oxide; 2 milligrams of cupric oxide
|No Intervention: 4|
AMD and cataract are the leading causes of visual impairment and blindness in the United States. Based on many clinical studies, it is apparent that the frequency of both diseases increases dramatically after age 60. Although excellent treatments for cataract are available, there are no equivalent treatments for AMD. As the average lifespan of our population increases, the number of people who develop AMD will increase dramatically in the years ahead. Unless successful means of prevention or treatment are developed, blindness from AMD -- and its importance as a public health problem -- will increase.
Neither the etiology nor the natural history of AMD or cataract is known. Epidemiologic studies suggest that a number of risk factors may be associated with AMD and cataract, but the strength of the evidence in support of these hypotheses varies. Possibly associated with AMD are personal characteristics, such as age, race, height, family history, and strength of hand grip; ocular characteristics, such as hyperopia and color of iris; and cardiovascular diseases, smoking, lung infections, and chemical exposures. Clinical and laboratory studies suggest the following factors may be associated with progression of AMD: drusen type, choroidal vascular diseases, and photic injury.
Epidemiologic studies of cataract suggest that associated risk factors may include personal characteristics, such as age, sex, race, occupation, and educational status; ocular characteristics, such as iris color; and diabetes mellitus, hypertension, drug exposure, smoking, and sunlight exposure. Animal studies and observational epidemiologic studies suggest that deficiencies in vitamins C and E, carotenoids, and the trace elements zinc and selenium also may be associated with the development of the two diseases, especially cataract. Although surgical treatment to remove cataract is very effective, cataract surgery carries risks, as does any other surgery. Therefore, many research efforts focus on preventing or slowing cataract development, as well as on determining the causes of cataract formation.
The Age-Related Eye Disease Study (AREDS) is a major research program to improve our understanding of the predisposing factors, clinical course, and prognostic factors of AMD and cataract. Eligible patients are randomized to treatment with placebo, antioxidants, zinc, or antioxidants plus zinc, and are followed for a minimum of 5 years.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00000145
|Principal Investigator:||Emily Y. Chew, MD||National Eye Institute (NEI)|