Age Related Macular Degeneration

Age-related macular degeneration (abbreviated to AMD, otherwise referred to as age-related maculopathy) is a condition wherein gradual damage to the macula – the central part of the retina – results in progressively worsening central vision.

It is a major cause of visual impairment in older adults. AMD can make it difficult for patients to recognize faces, read, or focus on close objects; although peripheral vision is usually sufficient for day-to-day tasks.

Causes

Risk factors for AMD have been identified to include the following:

·         Old age;

·         Smoking;

·         Genetics;

·         Fair skin;

·         Insufficient dietary intake of omega-3 fatty acids; and

·         High blood pressure.

Disease pathway

There are two forms of AMD: dry and wet. A large majority of patients with AMD suffer from the dry form. With dry AMD, the gradual loss of cells over time causes the tissue in the macula to thin.

The rarer, wet form of AMD starts off in a similar manner to the dry type. During the process, however, blood vessels under the macula begin to leak blood and fluid into the area. The accumulation of these substances eventually forms a mound of scar tissue.

Symptoms and diagnosis

For both forms of AMD, central vision progressively worsens (although this process tends to be accelerated in wet AMD). Fine detail becomes imperceptible, and distortion of vision may occur.

Doctors can diagnose macular degeneration by magnifying and examining. The retinal damage is usually visible before symptoms are noticeable.

Treatment

There is no treatment currently available, or recommended, to reverse the effects of AMD.

Efficacy of Alternative and Other Treatments According to GRADE* Ranking:

Photodynamic Therapy:

Recommendation: Weakly in favor (Photodynamic therapy is used as a treatment for wet age-related macular degeneration)

Grade of Evidence: very low quality of evidence

Vitamin E Supplement [1, 2, 3]:

Recommendation: Weakly in favor (Early studies show that vitamin e may be able to slow the progression of AMD. More studies are needed)

Grade of Evidence: Low quality of evidence

Zinc [3, 4]:

Recommendation: Weakly in favor (Early studies show that zinc may be able to slow the progression of AMD. More studies are needed)

Grade of Evidence: Low quality of evidence

Vitamin C [3]:

Recommendation: Weakly in favor (Early studies show that vitamin e may be able to slow the progression of AMD. More studies are needed)

Grade of Evidence: Low quality of evidence

Beta Carotene [3]:

Recommendation: Weakly in favor (Early studies show that beta carotene may be able to slow the progression of AMD. More studies are needed)

Grade of Evidence: Low quality of evidence

Lutein [5]:

Recommendation: No recommendation (There is insufficient evidence to show that lutein is able to treat AMD)

Grade of Evidence: Very low quality of evidence

 * www.gradeworkinggroup.org

Summary References:

1. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2881167/

2. http://www.ncbi.nlm.nih.gov/pubmed/12098721

3. http://www.ncbi.nlm.nih.gov/pubmed/11594942

4. http://knowledgeofhealth.com/special-report-antioxidants-zinc-for-macular-degeneration/

5. http://www.ncbi.nlm.nih.gov/pubmed/19234943