Prevalence and associations of epiretinal membranes in a rural Chinese adult population: The handan eye study

PURPOSE. To determine the prevalence and association of epiretinal membranes (ERMs), as assessed by retinal photography and optical coherence tomography (OCT), in a Chinese population. METHODS. The Handan Eye Study is a population-based study of eye disease in rural Chinese aged 30+ years. Eligible residents underwent a detailed ophthalmic examination including retinal photography and Stratus OCT. ERMs were defined by a combination of retinal photographs and OCT and classified as cellophane macular reflex (CMR) or preretinal macular fibrosis (PMF) based on retinal photographs characteristics. RESULTS. Of the 6830 persons examined, 6565 (96.1%) had gradable retinal photographs and/or OCT. The mean age was 51.7 ± 11.6 years. ERMs were present in 3.4% (95% CI: 2.9%-3.8%) of participants, bilateral in 20.3% of the cases. CMR was present in 2.2% and PMF in 0.7%, and ERMs were unclassified in 0.5% (detected by OCT only). ERM prevalence was similar in women and men (3.6% vs. 3.1%), strongly associated with increasing age (P for trend < 0.001). After adjustment for age and sex, primary ERM was associated positively with myopia (OR: 1.58, 95% CI: 1.12- 2.23) and inversely with current smoking (OR: 0.61, 95% CI: 0.38-0.97, versus never smoked). Best corrected visual acuity was significantly worse in eyes with primary ERMs (mean LogMAR score lower by 0.07, 95% CI: 0.05-0.10) than eyes without ERMs, after adjustment for age, sex, and lens status. CONCLUSIONS. ERMs affect 3.4% of the population 30+ years of age and living in rural China. Idiopathic ERMs were associated with myopia, decreased visual acuity, and inversely associated with smoking.