title: Prevalence and associations of epiretinal membranes in adult Chinese: the Beijing eye study.
abstract: OBJECTIVE
  To determine the prevalence of epiretinal membranes in the adult Chinese population.
  
  
  METHODS
  The Beijing Eye Study, a population-based, cross-sectional cohort study, included 4439 subjects out of 5324 subjects invited to participate (response rate 83.4%) with an age of 40+ years. The present investigation consisted of 4378 (98.6%) subjects for whom readable fundus photographs (30 degrees nonstereoscopic colour images) were available. Assessing the fundus photographs, we differentiated two membrane types: cellophane maculopathy and premacular fibrosis.
  
  
  RESULTS
  Prevalence rate of epiretinal membranes was 2.2+/-0.2% (mean+/-SE) (95% confidence interval (CI): 1.9,2.5) per eye or 2.2+/-0.2% (95% CI: 1.8,2.7) per subject. In binary logistic regression analysis, the prevalence of epiretinal membranes was significantly associated with age (P<0.001; 95% CI: 1.07,1.12), visual field loss (P<0.001; 95% CI: 1.03,1.07), hyperopia (P=0.02; 95% CI: 1.01,1.18), and higher education (P<0.001; 95% CI: 1.29,1.74). Cellophane maculopathy showed a prevalence rate of 1.11+/-0.1% (95% CI: 0.9,1.3) per eye and 1.8+/-0.2% (95% CI: 1.4,2.2) per subject. Its prevalence was significantly associated with age (P<0.001; 95% CI: 1.08,1.13), higher education (P<0.001; 95% CI: 1.26,1.92), and visual field loss (P=0.009; 95% CI: 1.01,1.07). Premacular fibrosis had a prevalence rate of 1.06+/-0.1% (95% CI: 0.9,1.3) per eye and 1.8+/-0.2% (95% CI: 1.4,2.2) per subject. It was significantly associated with age (P<0.001; 95% CI: 1.06,1.11), higher level of education (P<0.001; 95% CI: 1.15,1.74), and visual field loss (P=0.001; 95% CI: 1.02,1.08).
  
  
  CONCLUSIONS
  In adult Chinese in Greater Beijing, epiretinal membranes including cellophane maculopathy and premacular fibrosis occur in a relatively low frequency which may be lower than in Western countries. Epiretinal membranes including its subtypes of cellophane maculopathy and epiretinal fibrosis were associated with age and hyperopic refractive error.
authors: Beijing Institute of Ophthalmology, Beijing Tongren Hospital, Capital University of Medical Sciences, Beijing, China.
authors: Q
authors: Q
authors: You
authors: L
authors: L
authors: Xu
authors: J B
authors: JB
authors: Jonas
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D004522:Educational Status; D004812:Epidemiologic Methods; D019773:Epiretinal Membrane / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012423:Rural Health / Q000706:statistics & numerical data; D014504:Urban Health / Q000706:statistics & numerical data; D014786:Vision Disorders / Q000453:epidemiology / Q000209:etiology; D014794:Visual Fields