Age Related Macula Degeneration
Age Related Macula Degeneration is the leading cause of blindness in the Western world accounting for 15.4% (Western Europe) to 19.5% (Eastern Europe) of the blindness burden (vs 5.9% of world blindness burden). Macula Degeneration New Zealand estimate that it affects around 200,000 New Zealanders.
It appears in various forms and is classified as follows:-
1. Early Age Related Macula Degeneration: which is the most common, occurring in around 30% of those aged over 75 and can also be described as ‘dry type Age Related Macula Degeneration’
- Defined by the presence of numerous small ‘hard’ or intermediate size ‘soft’ drusen. (Small drusen are frequently seen in those aged 50 and older and can simply represent signs of ageing, therefore, intermediate drusen are more specific for Age Related Macula Degeneration).
- The word drusen (singular) is derived from the German word for potato stone or geode. They accumulate because the retinal pigment epithelial (RPE) isn’t functioning well, so it can’t do its job properly. This means that waste materials from its various functions are not processed or discarded properly
- Changes in the RPE including loss of pigment or clumping of pigment in a kind of moth-eaten appearance
Early ‘dry’ Age Related Macula Degeneration showing small drusen of ageing or early Age Related Macula Degeneration, courtesy of Retin Image Bank
2. Intermediate Age Related Macula Degeneration: is characterised by either extensive drusen of small or intermediate size, or any drusen of large size (≥125 microns) (to help you to visualise what is happening in these photos, consider that 124 micron is the average diameter of retinal vein at the optic disc margin)
Intermediate Age Related Macula Degeneration photo courtesy of Retinal Image bank- ‘hard’ drusen, small with a demarcated edge, ‘soft’ drusen, generally larger with a fluffy edge.
3. Advanced Age Related Macula Degeneration: is defined by the presence of either a) choroidal neovascular membrane (CNV), so called ‘Wet’ type Age Related Macula Degeneration or b) geographic atrophy (GA).
a) ‘Wet’ type:
- Cumulative oxidative injury
- Inflammation is a component of what causes and drives these processes
- Advanced Glycation Endproducts (AGE’s) drive inflammation
- Bruch’s membrane on which the RPE cells sit in a sheet becomes thickened, making the passage of oxygen and nutrients between the choroid and the retina difficult
- The choroid becomes thin and therefore less able to supply oxygen and nutrients to the retina
The retina has insufficient oxygen and nutrient so it sends out distress signals. The eye responds by trying to grow new blood vessels to meet the demand, but the new vessels are abnormal and fail to deliver the much needed supplies. These abnormal blood vessels grow in a membrane and are called choroidal neovascular membranes (CNV)
- The abnormal blood vessels in this membrane leak, bleed and have active scar forming cells and therefore the consequences include haemorrhage or fluid and fibrosis (scarring) under the retina that, causing visual loss in the central vision via leakage and bleeding. Conventionally this is treated with repeated injections (e.g. Avastin, Eylea and Lucentis) that block the distress signal. This gives the retina chance to dry out, reducing the swelling and vision can return to normal. The CNV shrinks and mostly the injections can be stopped. CNV often return and there is a high chance that the other eye will also become affected and need treatment.
b) Geographic atrophy can occur as a result of previous drusen or CNV or as a gradual loss of light sensitive cells
- the greatest problem is with the RPE. They become dysfunctional, then gradually waste away. All layers of the retina are also affected
- The choroid or blood vessel layer also becomes wasted and thinned
Geographic Atrophy, photo courtesy of Retina Image Bank. Here the pale area is where the retina has become so wasted or near absent that the large blood vessels of the underlying choroid are showing through.
- Cigarette smoking
- Ethnicity - Age Related Macula Degeneration is more common in Caucasians, than Chinese individuals, followed by Hispanic and least common in African-American
- Genetics play a role in about 23% of advanced Age Related Macula Degeneration
- Diets low in beta-carotene, vitamins C and E, and zinc
- Diets high in poor quality, oxidised fats including vegetable oils
- Diet low in omega-3 fatty acids such as found in fish and eggs
- Modern Western diet versus a traditional Mediterranean diet
- High carbohydrate diet
- Advanced Glycation End-products accumulate in Bruch’s membrane contributing to its thickening and dysfunction and Age Related Macula Degeneration are important drivers of inflammation in Age Related Macula Degeneration (as well as in atherosclerosis and Alzheimer’s disease)
What Can We Do About It?
It is well recognised that Age Related Macula Degeneration isn’t simply a natural consequence of ageing, although we all know that most things are compounded by the march of ‘Father Time’.
In some people, there is indeed a genetic component. This is more likely to be the case if you have a family history of Age Related Macula Degeneration. For the majority of people, Age Related Macula Degeneration is recognised as a lifestyle disease, which is how we view diabetes, cardiovascular diseases and some cancers. Diet plays a part in the development of Alzheimer’s and Parkinson’s disease, with research ongoing in these areas.
Interestingly if you have Age Related Macula Degeneration, you have a greater risk of being diabetic, having cardiovascular disease and Alzheimer’s disease. They are linked and associated with the same dietary pattern.
It is very common to be advised by your ophthalmologist to take dietary supplements. This is thought to make a difference in how your disease worsens over the course of your life by up to 30%!
Diet and Lifestyle
Look after your general health, attending closely to your diet, control inflammation, control weight, blood pressure, cholesterol etc. Stopping smoking is an absolute must, and fret not; there’s help out there for you on that score too!
There are foods and nutrients that can make your Age Related Macula Degeneration better and worse. Increase the former and decrease the latter.
These should always be determined for each individual depending on their unique set of diseases.
These should also be aimed at how we know Age Related Macula Degeneration occurs and worsens. They might include herbs that improve blood flow, anti-oxidant herbs, anti-inflammatory herbs, herbs that strengthen blood vessels etc.
Consider 2-RT laser (for dry/early Age Related Macula Degeneration only)
For Early/dry Age Related Macula Degeneration, 2-RT laser (Retinal Rejuvenation) is being trialled and its results over a 4 year follow up period show very encouraging results. Treatment of dry Age Related Macula Degeneration with 2-RT laser has been demonstrated in a study of over 200 patients to decrease the progression of the dry type to the wet type by over 70% when compared to doing nothing.
I have had the privilege of working with many people with wet type Age Related Macula Degeneration and some simple changes have brought forth comments such as ‘I haven’t felt this well in year’, ‘I don’t get colds nearly as often’, ‘my skin is better’, ‘I’m losing weight’, ‘my nails are stronger’.
Once again, if you nourish your eyes, you nourish your body and vice versa.
Contact me to arrange your personal eye health consultation