The results of a systematic review of all published, and several unpublished, sources of global data on vision impairment and blindness, from 1980 to January 2012, were published in a special issue of The Lancet journal this week.The study found that visual impairment accounts for 2.7% of the overall global years lived with disability (YLD).
The largest global cause of YLDs from vision impairment is ‘other vision loss’ which makes up 29.5% of the total, primarily from trauma, plus occupational and idiopathic conditions. Second was uncorrected refractive error, which accounts for 26.5% of vision impairment, while cataracts are the third largest contributor at 22.4%. Glaucoma and macular degeneration together explain 10.7%.
Professor Rupert Bourne (pictured) of Anglia Ruskin University’s Vision and Eye Research Unit led the research group, which involved collaboration between 79 ophthalmologists and optometrists.
“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,” he said. “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.
“The age-standardised prevalence, which takes into account the changes in life expectancy, of blindness and visual impairment, decreased globally between 1990-2010. This points to the successful intervention in treating cataracts and other forms of blindness and infectious diseases such as trachoma.”
The findings form part of the Global Burden of Disease Study 2010 – the largest systematic effort to describe the global distribution and causes of a wide array of major diseases, injuries and health risk factors.