AREDS
(Age-Related
Eye Disease Study)
The
AREDS Study is a randomized,
placebo-controlled clinical trial of high-dose
supplementation with vitamins C and E, beta
carotene, and zinc for age-related macular
degeneration. This trial included 11 centers.
Abstracted From
Archives of Ophthalmology 2001;119:1417-1436
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DEFINITIONS |
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Randomized
= A scientific method is used to select
those who are put on treatment. Two groups
are necessary so that a statistically
significant difference can be detected
between those who were given treatment
versus those who were given no treatment
or placebo.
Placebo
=
A pill, supplement, or intervention which
simulates the treatment but does not
contain the materials studied. A typical
pill-shaped placebo is ''a sugar
pill."
High-Dose
= More than the recommended daily
requirement.
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Patient
Characteristics: The 4754 Patients
(55-80 years old) that were enrolled had either
extensive small drusen, intermediate drusen, large
drusen, noncentral geographic atrophy, pigment
abnormalities in 1 or both eyes, advanced AMD, or
vision loss due to AMD in 1 eye. At least 1 eye
had best-corrected visual acuity of 20/32 or
better.
Treatment:
Participants were randomly assigned to receive
daily oral tablets containing: (1) antioxidants
(vitamin C, 500 mg; vitamin E, 400 IU; and beta
carotene, 15 mg); (2) zinc, 80 mg, as zinc oxide
and copper, 2 mg, as cupric oxide; (3)
antioxidants plus zinc; or (4) placebo.
Results:
Participants with extensive small drusen,
nonextensive intermediate size drusen, or pigment
abnormalities had only a 1.3% 5-year probability
of progression to advanced AMD. Odds reduction
estimates increased when these 1063 participants
were excluded. Both zinc and antioxidants plus
zinc significantly reduced the odds of developing
advanced AMD in the higher-risk groups. The only
statistically significant reduction in rates of at
least moderate visual acuity loss occurred in
persons assigned to receive antioxidants plus zinc
(OR, 0.73; 99% CI, 0.54-0.99). No statistically
significant serious adverse effect was associated
with any of the formulations.
Conclusion:
Persons older than 55 years should have
dilated eye examinations to determine their risk
of developing advanced AMD. Those with extensive
intermediate sized drusen, at least 1 large druse,
noncentral geographic atrophy in 1 or both eyes,
or advanced AMD or vision loss due to AMD in 1 eye
(without contraindications such as smoking) should
consider taking a supplement of antioxidants plus
zinc as used in this study.
