AMD is a major cause of vision loss inthe worldwide population. The progressive chronic disease affects the central retina and is usually asymptomatic in its early stages. As the condition progresses, patients start accumulating white or yellow spots of a material called drusen, which becomes visible upon closer examination of the retina.
Most of the vision loss in AMD occurs in the later stages and is widely thought to be caused due to the ‘wet’ or ‘late dry’ process. In the former process, a sudden leakage of blood and fluids occurs in the central retina, causing a rapid deterioration in vision and subsequent blindness due to scarring. The latter ‘late dry’ form involves experiencing a progressive loss of vision due to a slow degeneration and decline in retinal function.
Treatment for wet AMD has advanced with the development of two drugs, Lucentis and Avastin. Both drugs are targeted to suppress vascular endothelial growth and study data suggests they are able to prevent severe vision loss in 95% of patients and greatly improve 40% of vision. Lucentis is currently much more expensive than Avastin. However, Lucentis has been approved for treating AMD while Avastin has not yet seen approval, though it is widely used on an off-label basis.
Environmental and lifestyle factors have a great impact on AMD. Smoking has been repeatedly found to increase the risk of developing AMD. Other risk factors include obesity and a lack of antioxidant levels in one’s diet. Other risk factors include having a darker iris, prior cataract surgery, or being-long sighted are also known to increase the risk.
Apart from Lucentis and Avastin, there are several other new drugs in development. Research is examining potential roles for anti-inflammatory drugs, genetic approaches, stem-cell therapy, and retinal prostheses.
The authors conclude, “Age-related macular degeneration is a major cause of visual impairment in older adults. A host of novel treatment modalities, including inhibition of other angiogenic factors, new preventive approaches, regenerative therapy, and visual prostheses, are on the horizon. These hold the promise of even better outcomes in the near future."
mes in the near future."