The Macular Degeneration Epidemic: Beyond UV Protection
by: Dr. Gary L. Morgan
ep•i•dem•ic: Affecting or tending to affect a disproportionately large number of individuals within a population; usually something unpleasant.
The number of people with Age-related Macular Degeneration (AMD) will increase significantly over the next 20 years. The statistics are startling; 2.7 million Americans will develop Dry AMD, and 210,000 will develop wet AMD each year through the year 2050. There currently are 2,321 Retinal Specialists registered with the American Academy of Ophthalmology. Some quick, back-of-the-envelope math shows we are woefully underprepared for the coming AMD epidemic. So, what can we do as eyecare practitioners? In an infectious epidemic, measures such as quarantine, improved hygiene, vaccinations, etc. are undertaken to stop its spread. AMD is largely inherited with underlying systemic and environmental causes. Therefore, comprehensive programs for detection, risk assessment, education, monitoring, treatment programs, and prevention must be undertaken to limit the effects of AMD. As a profession, we are uniquely qualified (and even obliged) to lead the fight against this devastating disease.
There is a growing body of evidence that cumulative lifetime exposure to blue wavelength light increases the risk of AMD. Developmentally, by early childhood, the cornea and crystalline lens of the eye effectively block ultraviolet light from reaching the retina1, 2 . However visible light, which includes blue wavelength light, is transmitted to the retina and macula. The Beaver Dam Eye Study found that subjects in their teens through thirties, when exposed to an additional 3 hours of sunlight per day (over a normal exposure rate of 2 hours) advanced the onset of AMD in their lives by 10 years, effectively doubling the likelihood of becoming blind during a lifetime3 . Another well established risk factor for developing AMD coincident with blue light exposure is low macular pigment, which consists of the carotenoids mesozeaxanthin, zeaxanthin, and lutein (Figure 1). Lutein and zeaxanthin are dietary and found in foods such as spinach, brightly colored bell peppers and egg yolks. However, the Centers for Disease Control (CDC) estimates that the average daily intake of lutein and zeaxanthin in the US is approximately 2 mg, which is well below that shown to reduce the risk of age-related eye disease4 . Mesozeaxanthin is also dietary, but is not found in foods normally consumed, (i.e. skin of trout and salmon, shrimp shells, and turtle fat), yet has been shown to be the strongest of the three in terms of its antioxidant capabilities5 ……
Source: Energy Focus, INC.