Eyeworld

EW GLAUCOMA 50 by Tony Realini, MD, MPH Glaucoma from a global perspective How big is the problem and how can we solve it? T here are nearly 40 million blind people in the world today, according to Ivo Kocur, MD, team leader on public eye health with the World Health Organization. Another 285 million have visual impairment. Of the 40 million who are blind, half are blind from an easily curable condition—cataract. "Yes, there are still 20 million people blind from cataract in the world," he said at the 2013 annual meeting of the American Glaucoma Society in Washington D.C. Glaucoma, he added, remains the leading cause of irreversible blindness worldwide. Globally, 8% of all blindness is attributable to glaucoma. There were 60 million people with glaucoma in the world in 2010 and will be nearly 80 mil- lion by 2020. Of these 60 million, 7.4 million were bilaterally blind from glaucoma in 2010 and 11.2 million—14%—will be bilaterally blind in 2020. Regional variations When it comes to solutions for this global problem, one size will not fit all. The nature of glaucoma varies from region to region around the world. Likewise, the obstacles to care also vary regionally. In Asia, for instance, a large pro- portion of the glaucoma consists of angle closure. Asians represent 87% of all the global angle closure, and this condition typically requires laser or surgical intervention, which complicates the quest for a solution. Surgery—whether laser-based or in- cisional—is more expensive and has a more serious adverse event profile than medical therapy, and requires a higher level of technical expertise on the part of providers. These are sig- nificant obstacles to care in many developing Asian countries, and may help explain why angle closure glaucoma causes disproportionately more blindness than open angle glaucoma: Globally, approximately 25% of all primary glaucoma is angle closure, but by 2020, nearly half of all glaucoma blindness will be from angle closure glaucoma. In contrast, most glaucoma in the African-derived developing world is open angle glaucoma. The prevalence of open angle glaucoma in Africa and the Caribbean is 3- to 5-fold higher than in predominantly Caucasian populations. On the is- land of St. Lucia in the West Indies, for instance, the prevalence of glau- coma approaches 9% (in comparison to less than 2% in the U.S.), and the 10-year incidence of blindness from glaucoma is 16%. The barriers to care in the devel- oping world are numerous, said Dr. Kocur. "There is a lack of awareness about the disease, in part because it is asymptomatic until the later stages. Early diagnosis is difficult with the tools we have available today. For those who are diagnosed, compliance with daily medical ther- apy can be poor, and there are lim- ited resources in terms of expertise and equipment to provide more advanced interventions," he said. Screening and diagnosis It is a troubling paradox that the regions with the highest glaucoma burdens are often the least well equipped to provide adequate care for the disease. In the U.S., we take our resources for granted: perimeters with progression detection software, spectral domain OCT imaging of the nerve fiber layer, a glaucoma special- ist just down the street—if not just down the hall. This lack of resources limits the impact achievable in the quest to prevent glaucoma blindness. "As much as 90% or more of glaucoma in developing countries is undiagnosed and entirely un- treated," said Robert Ritch, MD, New York Eye and Ear Infirmary, New York. "Glaucoma in these countries seems to be an almost insurmountable problem." Screening for glaucoma is prob- lematic even in developed nations. In the developing world, however, there is little reason to undertake massive screening efforts to identify these undiagnosed people. "People who are advised that they are at risk for glaucoma-related visual impair- ment do not know where to go, can- not afford to go, or have nowhere to go to receive care," said Dr. Kocur. Solutions Addressing the global burden of glaucoma requires a three-pronged approach. First, providers in regions where glaucoma is highly prevalent need to be trained to treat the disease. This may take the form of fellowships for existing providers who wish to expand their glaucoma care knowledge. "The International Council of Ophthalmology (ICO) offers a number of fellowships, ranging in duration from 3 months to 1 year, for ophthalmologists from developing countries to learn more about subspecialty eyecare," said Dr. Ritch. Among the ICO's programs is one to teach the teachers, especially those from developing nations, who can then teach other ophthalmolo- gists in their home countries, thus providing education onsite where it is most needed. "The intent is to make education available in devel- oping countries without the need for travel and without removing the providers from their communities for up to a year," he explained. The second unmet need is for more effective therapies that do not rely upon daily instillation of med- ications. Adherence to medications February 2011 May 2014 Source: Karl Brasse, MD, EyeLand Design

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