Global Study on Disease Determines the Impact of Visual Impairment on the World’s Population
|December 14, 2012 12:21 AM
CAMBRIDGE, U.K.—Visual impairment accounts for 2.7 percent of the world’s total of “years lived with disability” due to the impact of nearly 300 diseases ranging from maternal and child illness to malnutrition, which was examined in a new international study, just released yesterday in a special issue of
Based on a global collaboration of 79 ophthalmologists and optometrists known as the Vision Loss Expert Group and led by professor Rupert Bourne of
Anglia Ruskin University’s Vision and Eye Research Unit, the findings form a part of the
Global Burden of Disease Study 2010, described as “the largest ever systematic effort to describe the global distribution and causes of a wide array of major diseases, injuries and risk factors.” The study examined 291 various diseases and 67 risk factors covering 21 regions around the world. This is the first time The Lancet has devoted a single issue entirely to one study.
Funded by the
Bill and Melinda Gates Foundation, with a
Fight for Sight grant assisting with the technical modelling of temporal trends of blindness over the past 30 years, the study is expected to assist in the distribution of resources and serve as an advocacy tool in pursuing the aims of
VISION 2020: The Right to Sight, a global campaign to eliminate avoidable blindness.
Visual impairment accounts for a cumulative 21.1 million years lived with disability among the world’s population, the study said. The largest global cause of years lived with disability from vision impairment, the study relates, is “other vision loss,” composing 29.5 percent of total vision impairment and coming primarily from trauma, occupational and idiopathic conditions. Uncorrected refractive error is second and accounts for 26.5 percent of vision impairment while cataracts, at 22.4 percent, are the third largest contributor to years lived with disability due to vision impairment.
Glaucoma and macular degeneration account for 10.7 percent, and trachoma and onchocerciasis (also known as river blindness) account for 2.1 percent of total years lived with disability. The majority of blindness and low vision are concentrated in older ages, particularly those 45 years and older. There has been an increase in the absolute number of years lived with disability from blindness and low vision since 1990, the study also found, and uncorrected refractive error, trachoma, onchocerciasis and vitamin A deficiency play a much greater role in Sub-Saharan Africa than in other regions.
“The overall increase in the number of people suffering from blindness and vision loss is due to the huge population explosion that has occurred during the last couple of decades,” said Bourne. “However, the Global Burden of Disease findings actually show that this increase is not as large as one would expect given the increasing life expectancy in the world’s population over this time.”