The data, revealed in medical journal The Lancet, showed the international level of blindness in adults over age 50 caused by the easily treated condition has declined only slightly from 36.7% in 1990 to 35.1% in 2015. Furthermore, it also predicted the rate would only decline to around 34.7% by 2020.A lack of access to eye healthcare and services among low and middle-income countries was highlighted as a major issue, while the skyrocketing number of people aged 50 and over meant the worldwide number of blind individuals is likely to triple by 2050.However, according to study co-author Professor Serge Reskinoff, there was some good news.The prevalence of vision loss has been steadily decreasing over the past 25 years and millions of cases of blindness have been averted. The bad news is that the prevalence is now starting to increase and the proportion of avoidable visual impairment is raining almost the same,” he said.Currently, around 12.6 million people are blind due to cataract, nearly double the next highest cause, uncorrected refractive error, which affects approximately 7.4 million people worldwide. Combined, cataract and uncorrected refractive error contributed to 55% of blindness and 77% of vision impairment in adults aged 50 years and older in 2015.Nevertheless, Reskinoff also explained the probl wasn’t limited to those to conditions, and that Asia appeared the most vulnerable in terms of the increasing prevalence of vision impaired people.“Projections to 2020 show that we are not going to achieve the target that WHO has set in its global action plan. This is mainly happening because of three factors: the rapid ageing of the population and the myopia and diabetes “epidics”,” he said.“Asia is the continent where the resurgence in prevalence of vision impairment is the most marked, especially because this is the continent where changes in myopia prevalence and ageing are particularly significant. Massive scale up in provision of services is needed to outpace these two factors.”The research encompassed 288 studies of 3,983,541 participants, contributing data from 98 countries.More reading: The full study.