Global prevalence of avoidable vision impairment and blindness in adults aged 50 years and older did not change between 2010 and 2019, suggesting the World Health Assembly Global Action Plan* (WHA GAP) did not achieve its target of a 25% reduction.
A review, published by The Lancet Global Health, found the 2019 prevalence was 9.58 cases per 1000 people compared to 96.0 cases per 1000 people in 2010. Age-standardised prevalence of avoidable blindness decreased by −15.4%, while avoidable moderate and severe vision impairment (MSVI) showed no change. The actual number of cases increased for both avoidable blindness (10.8%) and MSVI (31.5%).
Leading global causes of blindness in those aged 50 years and older in 2020 were cataract (15.2 million cases) followed by glaucoma (3.6 million cases), under corrected refractive error (2.3 million cases), age-related macular degeneration (1.8 million cases) and diabetic retinopathy (0.86 million cases). The leading causes of MSVI were under-corrected refractive error (86.1 million cases) and cataract (78.8 million cases).
The results suggest eye care services contributed to the reduction of age-standardised rates of avoidable blindness but not MSVI, said researchers, adding that the target in an ageing global population was not reached.
*The World Health Organisation (WHO) and the International Agency for Prevention of Blindness (IAPB) created an initiative in 1999 called “Vision 2020: The Right to Sight”. In 2013, the World Health Assembly (WHA) launched a global action plan 2014–2019 (GAP), setting a target to achieve a 25% reduction by 2019 from the baseline of 2010 in global prevalence of “avoidable” visual impairment, defined as the aggregated crude prevalence of cataract and under corrected refractive error (presenting visual acuity (<6/18).