Inherited Retinal Disorders

There are many inherited retinal diseases. These disorders often affect the macula which is the part of the retina responsible for sharp central vision used for reading and driving.

These diseases are characterized by being familial, bilateral, and often symmetrical. They can cause severe vision loss and are often slowly progressive.

Other hereditary diseases cause a more generalized destruction of the entire retina. Again, these diseases are familial, mostly bilateral and slowly progressive. Retinitis Pigmentosa is the most widely known of the latter group.

While there are visual aids to help people with these diseases, there is, at this point, no satisfactory treatment of the diseases themselves.

DIETARY SUPPLEMENTATION FOR PATIENTS WITH RETINITIS PIGMENTOSA

A recent study in the Archives of Ophthalmology reported that Vitamin A palmitate (1,500 IU per day) helped to preserve retinal function in patients with retinitis pigmentosa. A subsequent study reported that Docosahexaenoic acid (DHA, an omega 3 fatty acid) provided a benefit that was limited to those patients starting Vitamin A palmitate for the first time. In these patients, DHA supplementation slowed the course of retinitis pigmentosa for the first two years in patients also being started on Vitamin A. We therefore recommend Vitamin A palmitate 1,500 IU per day and DHA 500 to 600 mg. twice a day for patients with retinitis pigmentosa who have not been using any vitamins.

For patients who are already taking Vitamin A, we recommend Vitamin A palmitate 1,500 units per day but do not recommend that DHA be started.

An additional study reported that patients eating a diet rich in Omega 3 fatty acids such as salmon, tuna, mackerel, herring, or sardines, have a 40 to 50 percent slower annual rate of visual loss than patients with a low Omega 3 rich dietary intake. We therefore recommend a diet high in these fish (three times per week).

Vitamin A palmitate 1,500 IU is available from Orphan Medical. The trade name of this vitamin is Unilife-A. It can be ordered by calling 1-800-787-5577. For patients not previously taking Vitamin A, we recommend in addition to the Vitamin A mentioned above, a supplement of DHA 500 mg. twice a day which can be ordered from JR Carlson Laboratories, Inc. by calling 1-888-234-5656.

February 2005

[Go back]