Myopia macular atrophy in the two‐continent population‐based study

Aims/Purpose: To examine myopic macular atrophy (myopic macular degeneration (MMD) stage‐4) and myopic patchy atrophies (MMD‐stage‐3) in three ethnically different cohorts recruited in a population‐based manner.Methods: The population‐based Ural Eye and Medical Study (UEMS) and the Beijing Eye Study (BES) included individuals aged 40+ years, and the Ural Very Old Study (UVOS) examined individuals aged 85+ years.Results: Among 5794 UEMS participants, 19 eyes had MMD‐stage‐4, with 17 (89%) eyes showing a foveal BMD; two eyes could not fully be explored. All 19 eyes showed localized SRPs. Among 21 eyes with MMD‐stage‐3, BMD and SRP prevalence was 9/21 (44%) and 7/21 (33%), respectively. Among 930 UVOS participants, 17 eyes had MMD‐stage‐4, with 16 (94%) eyes showing foveal BMDs and SRPs; one eye could not clearly be assessed. Among 18 eyes with MMD‐stage‐3, BMD and SRP prevalence was 3/18 (17%) and 2/18 (11%), respectively. Among 3468 BES participants, 8 eyes had MMD‐stage‐4, with all eyes showing foveal BMDs and SRPs. Among 14 eyes with MMD‐stage‐3, BMD and SRP prevalence was 10/14 (71%) and 7/21 (33%), respectively. In all three study cohorts, BMD and SRP prevalence was higher (P < 0.001) in MMD‐stage‐4 than MMD‐stage‐3. In MMD‐stage‐3, 12 (55%) of 22 eyes with BMDs showed SRPs, while 12 (86%) of 14 eyes with SRP showed BMDs. SRP prevalence correlated with BMD prevalence (OR:78.3;95%CI:16.1,382).Conclusions: Independent of the ethnic background, all assessable eyes with myopic macular atrophy showed foveal BMDs associated with SRPs, while patchy atrophies could be differentiated into eyes with BMDs and SRPs and eyes without BMDs and without SRPs. The results suggest that SRP as sequel of myopic choroidal neovascularization is a complication of BMDs, and that patchy atrophies may develop due to a primary BMD with secondary RPE defect, or due to an expansion defect in the RPE without concomitant underlying BMD.