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With aging populations, age-related macular degeneration (AMD) is set to increase. AMD, which causes progressive blindness, mayalready be present in the early stages in 20% of 60 year-olds andthose who are older in some countries. Whilst 10 years ago therewere hardly any treatments for AMD, the age of targeted drugs likevascular endothelial growth factor (VEGF) suppressants has changedthe way in which AMD is controlled. In The Lancet Series on Ophthalmology , professor Tien Yin Wong from the Singapore Eye Research Instituteat the National University of Singapore, and his team discuss theissues that surround AMD. AMD is a leading cause for loss of vision worldwide. Theprogressive chronic disease affects the central retina and whilstthe condition is usually asymptomatic in the early stages, as thecondition progresses, patients start accumulating white or yellowspots of a material called drusen, which becomes visible onexamining the retina. Most of the visual loss occurs in the late stages of the conditionand is commonly brought on due to the 'wet' or 'late dry' process.In the former process, a sudden leakage of blood and fluids occursin the central retina, which could lead to a rapid deterioration invision and subsequent permanent visual loss due to scarring, whilstthe 'late dry' form involves experiencing a progressive loss ofvision due to a slow degeneration and decline in retinal function. The care for wet AMD has been transformed with the development oftwo drugs, i.e. Lucentis (ranibizumab) and Avastin (bevacizumab). Both drugs are targeted to suppress VEGF and dataindicates they are able to prevent a severe loss of vision in 95%of patients and considerably improve 40% of vision. At $1,593 USD, Lucentis is much more expensive per injection thanAvastin at $42 USD. However, Lucentis has been approved fortreating AMD, whilst Avastin has so far not yet been approved, eventhough it is widely used on an off-label basis. In the UK, Novartis, the manufacturer of Lucentis has startedtaking legal action in order to prevent the UKs National HealthService Trusts from using Avastin for this purpose. Given that boththerapies require monthly injections and long-term safety data arenot yet available, the paper has also raised safety issues ascontinuous suppression of VEGF may raise the risk of vascularevents, for which, according to the researchers, more data isneeded. Environmental and lifestyle factors have a major impact on AMD.Smoking has consistently proven to raise the risk of developingAMD. The same goes for obesity and having insufficient antioxidant levels in one's diet, likevitamin A, C, E and zinc. Older age is a risk factor that isnon-modifiable, i.e. nothing can be changed about it, having adarker iris, previous cataract surgery, or being long-sighted are also known to increase therisk. Another key discovery is that AMD has a strong genetic link,including genes associated with the immune system, HDL or good cholesterol , as well as those genes that are associated with mechanisms thataffect collagen, the eye's extra-cellular matrix, and angiogenesis,or the growth of new blood vessels. Aside from Lucentis and Avastin, there are currently other new VEGFsuppressant drugs in development. Research is investigating intopotential 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. Noeffective preventive drug therapies exist although nutritional andbehavioral modifications can reduce progression to advancedage-related macular degeneration...anti-VEGF therapies have provento be effective in reducing and, in some cases, reversing visualloss in those with AMD, although the monthly or bi-monthlytreatment burden is high and the systemic long-term safety of thesedrugs remains unclear. A host of novel treatment modalities,including inhibition of other angiogenic factors, new preventiveapproaches, regenerative therapy, and visual prostheses, are on thehorizon. These hold the promise of even better outcomes in the nearfuture." Written By Petra Rattue. I am an expert from swiss-lacefabric.com, while we provides the quality product, such as African Gele Fabric Manufacturer , Swiss Cotton Lace Manufacturer, Swiss Lace Fabric,and more.
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