Global prevalence of age-related macular degeneration and disease burden projection for 2020 and 2040: A systematic review and meta-analysis

Abstract

Background: Numerous population-based studies of age-related macular degeneration have been reported around the world, with the results of some studies suggesting racial or ethnic differences in disease prevalence. Integrating these resources to provide summarised data to establish worldwide prevalence and to project the number of people with age-related macular degeneration from 2020 to 2040 would be a useful guide for global strategies. Methods: We did a systematic literature review to identify all population-based studies of age-related macular degeneration published before May, 2013. Only studies using retinal photographs and standardised grading classifications (the Wisconsin age-related maculopathy grading system, the international classification for age-related macular degeneration, or the Rotterdam staging system) were included. Hierarchical Bayesian approaches were used to estimate the pooled prevalence, the 95% credible intervals (CrI), and to examine the difference in prevalence by ethnicity (European, African, Hispanic, Asian) and region (Africa, Asia, Europe, Latin America and the Caribbean, North America, and Oceania). UN World Population Prospects were used to project the number of people affected in 2014 and 2040. Bayes factor was calculated as a measure of statistical evidence, with a score above three indicating substantial evidence. Findings: Analysis of 129664 individuals (aged 30-97 years), with 12727 cases from 39 studies, showed the pooled prevalence (mapped to an age range of 45-85 years) of early, late, and any age-related macular degeneration to be 8·01% (95% CrI 3·98-15·49), 0·37% (0·18-0·77), and 8·69% (4·26-17·40), respectively. We found a higher prevalence of early and any age-related macular degeneration in Europeans than in Asians (early: 11·2% vs 6·8%, Bayes factor 3·9; any: 12·3% vs 7·4%, Bayes factor 4·3), and early, late, and any age-related macular degeneration to be more prevalent in Europeans than in Africans (early: 11·2% vs 7·1%, Bayes factor 12·2; late: 0·5% vs 0·3%, 3·7; any: 12·3% vs 7·5%, 31·3). There was no difference in prevalence between Asians and Africans (all Bayes factors