Age related macular degeneration

We tend to associate blindness with birth defects, trauma to the eyes and chronic diseases like diabetes. However, loss of vision resulting in blindness can also occur as a result of ageing.

Age related macular degeneration, unlike a simple refractory error which can be corrected with spectacles, results from degeneration to the innermost layer of the eye – the sensory retina. Unfortunately the condition is difficult to treat. It is the leading cause of blindness in people over the age of 60 inSouth Africa.

Pharmacist, I’m going blind

People who gradually lose their vision rarely have insight into their condition. It’s usually up to a loved one to point out that their friend or partner is unable to recognize faces or read.

The other problem is that people with age-related macular degeneration generally think they’re simply becoming far-sighted or have cataracts rather than suffering from a degenerative eye condition.

What is age-related macular degeneration?

The “macula” is the area on the retina (the light sensing inner layer of the eye) with the highest visual capability. It is responsible for our central vision, which allows reading and detailed recognition.

In age-related macular degeneration, the retinal layer (in the macular area) becomes separated from the underlying layer (known as the choroid). In “wet” macular degeneration this is caused by blood vessels growing between the retina and choroid (accounting for 10% of all AMD) and in “dry” macular degeneration (accounting for 90% of all AMD), this is due to a collection of debris accumulating between the retina and choroid.

How is age-related macular degeneration diagnosed?

The only way to diagnose age-related macular degeneration (AMD) is by viewing the retina through an ophthalmoscope or other retina-viewing equipment.

Usually an ophthalmologist will diagnose and treat this eye condition. The retina shows signs of damage in keeping with the condition. This, along with the visual loss typical to the condition makes the diagnosis.

Treatment

There’s really nothing in the way of over-the-counter treatment you can offer you clients with established AMD.

An ophthalmologist will be able to offer certain treatments to your client depending on the type and severity of AMD.

There is no treatment for dry AMD, but there are treatments for wet AMD including:

• Agents which reduce blood vessel growth:  Usually these are injected directly into the eye. They include medications such as ranibizumab (e.g. Lucentis®), bevacizumab (e.g. Avastin®) and pegaptanib (e.g. Macugen®).
• Laser photocoagulation: Laser therapy can help manage certain types of wet AMD

Counselling clients about AMD

AMD is a preventable disease and preventing the condition is all about educating your clients about eye health and encouraging them to prevent the disease.

Since there is no real cure for the majority of people with the condition it is very important to alert your clients to the risk of this little known condition.

Make sure you warn your clients about their genetic risk.  AMD affects 5% to 20% of the South African population over the age of 65. It is more common in fair-skinned individuals. Anyone with a family member who has AMD should be more aware of their risk of the disease and go for more regular screening.

You should encourage clients to:

• Avoid UV exposure by wearing protective eyewear: clients should ensure they wear polarised lenses which offer adequate UV protection
• Avoid tobacco exposure as this can increase their risk of disease
• Keep high blood pressure well controlled
• Eat their spinach! A daily intake of at least 2.4mg per day of antioxidants such as lutein and zeaxanthin found in spinach, broccoli, kiwi fruit, eggs, maize, zucchini and Brussel sprouts has been recommended by the American National Eye Institute to reduce the risk of AMD. Your client can take supplements such as Solal Lutein®, Ocu-Plex® or NutraSight® if they are unable to get these nutrients from their diet.
• Go for regular (annual) eyesight screening with a registered optometrist

Getting your clients to see the light

The most important role you play in AMD, is getting clients to see an optometrist if they are losing their eyesight. Eyesight in someone over the age of 60 (especially someone who is fair-skinned) which is not corrected by over-the-counter spectacles, always requires a check-up by a professional.

South Africans tend to take their eyesight for granted. The climate (sunlight exposure) and our genetics mean that we are particularly at risk of AMD.