Craig Blackwell, MD
Ophthalmology

Santa Cruz, CA
Diplomate: American Board of Ophthalmology
Fellow: American Academy of Ophthalmology

Welcome to the Website of Craig Blackwell, MD

An Ophthalmology Practice in Santa Cruz, CA

AREDS: Vitamin Supplements and Macular Degeneration

Macular Degeneration (AMD) is one of the biggest unsolved problems in ophthalmology. In the later decades in life there is gradual deterioration of the central part of the retina resulting in reduced central vision for reading and seeing details.

Retinal Photo of moderate Macular Degeneration (AMD).

The yellow spots, called “drusen,” are the accumulation of waste products in the pigmented layer under the retina. There is no leakage, so this is the “dry” type.

There are two general categories of AMD:

  • The “Dry” type: There are drusen and or atrophy, but there is no leakage of serum or blood. Vision worsens progressively, but slowly.
  • The “Wet” type. Starts as dry, but at some point new blood vessels invade the space under the retina. The new vessels leak serum or blood which causes a relatively rapid and severe loss of central vision.

Historically, there was nothing we could do about dry type, except maintain a vigil for development of leakage. If leakage developed, and was caught early, a laser could be used to cauterize the leaking vessels. More recently this is being treated with an injected medication.

In 1988 a small study was published (Newsome, Arch Ophthal 1988; 106: 192-198) suggesting dietary supplement with the mineral zinc could slow progress of macular degeneration. That led to a much larger nationwide study looking at age-related eye diseases, particularly cataract and macular degeneration, to see if supplementation with antioxidant vitamins and or zinc would be of help.

AREDS

AREDS, the Age Related Eye Disease Study, followed almost 5,000 people for ten years. They were divided into the following treatment groups:

  • Antioxidant Vitamins (daily dose):
  • Beta Carotene 15 mg; Vitamin C 500 mg; Vitamin E 400 IU

  • Minerals: Zinc 80 mg; Copper 2 mg
  • Antioxidant Vitamins and Zinc
  • Placebo

After AREDS started two contemporary studies looking at vitamins and lung cancer found that smokers who took Beta-Carotene had increased risk of lung tumors and mortality. Smokers in the study were allowed to drop out or change to a supplement without Beta-Carotene. For more details about the Vitamin A question click on Vitamin A and AREDS.

Copper was included because Zinc and Copper compete for absorption so if you supplement one you must balance with the other.

The above vitamin dosages are available by taking 2 tablets of Preservision (Bausch & Lomb) or 4 tablets of ICaps (Alcon).

The Study

There are several things you need to know to understand the study result.

At the outset each participant’s retina was graded according to the severity of the AMD. The grading was on a scale of 1 to 4, from mild to advanced, represented on the chart below by the different colors.

The Dry Type, given enough time, can progress to wasting or “atrophy” of the central retina with severe vision loss.

The Results

Arch Ophthal 2005;123:1570-1574.

The above graph summarizes the study results over 10 years of followup.

The X-axis is years. The Y-axis is the percentage of people that developed advanced vision loss, either from the dry type advanced to atrophy or from the wet type.

Within each group half received placebo, and half the supplement. The dashed line represents those receiving a placebo. The solid line represents those receiving both antioxidant vitamins plus zinc.

It is fairly clear that within each group taking the vitamins lessened the chance of developing severe vision loss. It did not reverse degeneration or eliminate vision loss, but it did provide a measurable benefit.