Prevalence of macular complications related to myopia - Results of a multicenter evaluation of myopic patients in eye clinics in France

Purpose: Uncorrected refractive errors are the first cause of vision impairment worldwide. High myopia is a frequent cause of sight-threatening chorioretinal complications. The aim of this study was to evaluate the prevalence of macular complications, visual impairment and blindness in patients with myopia.

Methods: A cross-sectional multicenter study carried out in French eye clinics mainly dedicated to refractive errors. Myopia severity was defined as mild (-0.5 to -3 D), moderate (-3 to -6 D), high (-6 to -10 D) and very high (more than -10 D). Macular complications related to myopia included lacquer cracks, myopic choroidal neovascularization, chorioretinal atrophy and retinoschisis. The prevalences of macular complications, blindness and vision impairment were estimated with respect to degree of myopia and age. Eligibility criteria were myopia on the left eye of -0.5 D or more. Exclusion criteria included any missing data related to subjective refractive error, age, gender and any history of cataract or refractive surgery.

Results: Data files from 198 641 myopic individuals with a mean age of 34 years (SD: 15 years) were analysed. The prevalence of mild, moderate, high and very high myopia was, respectively, 65.95%, 26.14%, 6.72% and 1.19%. The prevalence of macular complications in the high and very high myopia groups was 0.5% [0.39-0.64] and 4.27% [3.49-5.17]. The prevalence of blindness or vision impairment was observed in 10.10% [8.91-11.39%] of the very high myopic group. At 60 years old or over, the prevalences of blindness or vision impairment were, respectively, 9.75% [7.91-11.85%] and 25.71% [21.00-30.87%] in the high and very high myopia groups.

Conclusions: This multicenter cross-sectional study provides new insights in terms of prevalence of macular complications related to myopia. To our knowledge, this is one of the largest European studies focusing on individuals with myopia, particularly on the macular complications and the functional consequences in relation to myopia.