Blindness is expected to become three times more prevalent across the globe within the next four decades, warn researchers.
According to a study published in Lancet Global Health, an estimated 36 million cases of blindness in 2015 is set to rise to 115 million by 2050, if funding for treatment is not increased.
Lead author Rupert Bourne (Anglia Ruskin University, Cambridge, UK) says the findings “highlight the need to scale up vision impairment alleviation efforts at all levels.”
A growing and ageing population is behind the expected increase in blindness rates. The proportion of people with blindness and visual impairment is actually steadily declining, but because the global population is growing and people are living for longer, the number of people affected by blindness is substantially increasing.
For the study, Bourne and colleagues performed a systematic review and meta-analyses of population-based data on visual impairment and blindness across 188 countries and used hierarchical models to estimate prevalence by age, gender and country.
The results indicated that more than 200 million people globally currently have moderate-to-severe visual impairment, with the figure expected to rise to more than 550 million by 2050.
Even mild visual impairment can have a significant negative impact on a person’s life, says Bourne. They may be barred from driving, for example, which reduces their independence. Their educational and economic opportunities may also be restricted.
The authors believe global and regional prevalence estimates for blindness and vision impairment are important for the development of public health policies. Their study calls for increased investment in procedures such as cataract surgery and for improved access to vision-correcting glasses.
The regions most affected by visual impairment were South and East Asia and sub-Saharan Africa. Yet certain interventions, which provide some of the largest returns on investment, can easily be implemented in such developing regions, claims Bourne: "They are cheap, require little infrastructure and countries recover their costs as people enter back into the workforce."
Imran Khan from the charity Sightsavers agrees that health systems in developing countries need to be improved and suggests that more surgeons and nurses are trained in the delivery of sustainable eye healthcare.