The prevalence, progression, and visual loss associated with myopic macular degeneration in Asia

This systematic review examines the epidemiology, natural history, and visual outcomes of myopic macular degeneration (MMD) in Asia. MMD is irreversible, may affect both eyes, and may occur during a person's productive years, making it a significant public health concern. Population-based studies report a wide variation in MMD prevalence, ranging from 0.24% in rural India to 4.5% in mainland China. MMD is etiologically heterogeneous, with its prevalence associated with a more negative spherical equivalent (SE), longer axial length (AL), older age, and a lower education level. The development of MMD is likely nonlinear, with the prevalence of MMD increasing markedly once specific thresholds in age (60-70 years), SE (-6 to - 7 diopters), and AL (about 26 mm) are exceeded. The 5-year, 6-year, and 12-year incidence of MMD is up to 1.1%, 1.2%, and 10.3% respectively. The 10-year progression rate of MMD may reach 35.5%, often involving the development or worsening of chorioretinal atrophy. MMD is associated with significant visual impairment (VI) and blindness, with a decrease in best corrected visual acuity (BCVA) ranging from one to 13 lines. Among individuals with MMD, up to 54.5% experience VI, and up to 14.9% develop blindness in the better eye. Up to 36.4%, 21.6%, 12.3%, and 4.5% of individuals with MMD have unilateral VI, bilateral VI, unilateral blindness, and bilateral blindness, respectively. BCVA loss increases with MMD severity. These findings underscore the urgent need for public health strategies to address the growing burden of MMD in Asia's aging and increasingly myopic populations.