Abstract
BACKGROUND: To report the global distribution of macular neovascularization type 3 (MNV3) and to redefine the associated burden of neovascular age-related macular degeneration (nAMD). METHODS: A total of 4652 patients with treatment-naïve nAMD were included. MNV3 was diagnosed using multimodal imaging methods. The prevalence of MNV3 in each country, region, continent and worldwide was calculated. The correlation between the prevalence of MNV3 and life expectancy in each country was estimated. Continent prevalence data was compared using a logistic (binomial) generalized linear mixed model (GLMM). RESULTS: Our analysis revealed 4652 nAMD eyes from 47 countries, 575 (12.4%) of which had MNV3. In North America, the highest percentage was in Canada (17.6%), followed by the USA (11.5%). In Europe, the highest prevalence (23.4%) was in Austria and the lowest (4.3%) in Russia and Croatia. The prevalence in Asia, South America, and Australia was 6.6%, 9.4%, and 13.7%. A significant positive correlation was found between the MNV3 prevalence and life expectancy in 20 European countries (r = 0.63, P < 0.003). The GLMM revealed significantly lower odds for observing MNV3 in Asia compared to Europe (P < 0.01). No significant difference was observed in any other continent pair. The prevalence in Western Europe and Mediterranean region was higher than in Eastern Europe and the non-Mediterranean region (18.6% vs. 9.6%, P < 0.001; and 17.5% vs. 12.6%, P = 0.001, respectively). CONCLUSIONS: MNV3 is more prevalent in Western and Mediterranean regions, likely because of higher life expectancy and a lower percentage of Asian ethnicity. AREDS supplements and the Mediterranean diet may not provide prophylactic benefits against the development of MNV3. The unique distribution pattern of MNV3 and its correlation with life expectancy should be considered in nAMD research to ensure adequate representation of MNV3 patients in clinical trials.