Epiretinal membranes: prevalence and associations in relationship to posterior vitreous detachment – the Beijing Eye Study

Purpose To assess prevalence and associations of epiretinal membranes (ERMs) in a general population. Methods In participants of the population-based Beijing Eye Study, we assessed macular volume optical coherence tomographic (OCT) scans for ERMs. Results The study included 1351 eyes (914 participants) (age: 64.7±9.8 years; range: 50–91 years). ERMs were detected in 80 eyes (5.9%; 95% CI 4.9% to 6.9%) of 60 participants (6.6%; 95% CI 5.1% to 8.1%), with ERMs without retinal surface wrinkling in 34 (2.5%) eyes, ERMs with retinal surface wrinkling and normal fovea contour in 16 (1.2%) eyes, ERMs with reduced foveal depth in 20 (1.5%) eyes, ERMs with complete foveal flattening in 6 (0.4%) eyes and ERMs with foveal elevation in 4 (0.2%) eyes. Hyper-reflective epiretinal dots (HEDs) were detected in 114 (8.4%) eyes. Higher ERM prevalence was associated (multivariable analysis) with higher stage of posterior vitreous detachment (PVD) (OR: 1.81; 95% CI 1.34 to 2.45; p<0.001), older age (OR: 1.05; 95% CI 1.01 to 1.09; p=0.002), higher prevalence of HEDs (OR: 9.18; 95% CI 4.85 to 17.4; p<0.001) and worse best corrected visual acuity (BCVA) (OR: 2.75; 95% CI 1.04 to 7.30; p=0.04), but not with axial length (p=0.69) or pseudophakia (p=0.98). Out of 746 eyes without PVD, 3 (0.4%) eyes had ERMs (without retinal surface wrinkling) and 9 (1.2%) eyes showed HEDs. Higher ERM stage increased with higher PVD stage (beta: 0.32; p<0.001), older age (beta: 0.11; p=0.006) and worse BCVA (beta: 0.07; p=0.04), but not with axial length (p=0.75) or pseudophakia (p=0.71). Conclusions As measured by OCT, ERM prevalence was mainly associated with PVD and to a minor degree with older age and worse BCVA, while longer axial length, pseudophakia or ocular diseases such as age-related macular disease and glaucoma were not related to prevalence and stage of ERMs.