[Jiangsu Diabetic Eye Disease Study：epidemiological survey of blindness and moderate or severe visual impairment in people with type 2 diabetes over 50 years old in Funing County].

Objective: To investigate the prevalence, causes and risk factors of moderate or severe visual impairment and blindness in people with type 2 diabetes over 50 years old in Funing County, Yancheng. Methods: This is a cross-sectional study. Using cluster random sampling, 84 survey sites were selected, and eye examination was performed on people with type 2 diabetes over 50 years old who were registered with the chronic disease information center of Funing County Center for Disease Control and Prevention in Yancheng, Jiangsu. The prevalence of moderate or severe visual impairment and blindness were calculated by different ages and genders. The causes of blindness and visual impairment were determined, and their influencing factors were analyzed by univariate and multivarite logistic regression. Results: A total of 2 067 people were investigated in this study, and 1 909 people were included. The response rate was 92.4%. Based on PVA, the prevalence of blindness and moderate to severe visual impairment was 5.29% (95%CI: 4.29%-6.30%) and 18.54% (95%CI: 16.80%-20.29%). The prevalence of blindness was related to age, marital status, education, duration of diabetes, history of diabetic nephropathy, systolic blood pressure and nuclear opacity. The prevalence of moderate or severe visual impairment was related to age, gender, educational level, diabetes treatment, exercise, and glycated hemoglobin. The prevalence of blindness and moderate to severe visual impairment was 3.67% (95%CI: 2.82%-4.51%) and 9.80% (95%CI: 8.46%-11.13%) based on BCVA. The prevalence of blindness was related to age, marital status, education, duration of diabetes, history of diabetic nephropathy, exercise and systolic blood pressure, while the prevalence of moderate or severe visual impairment was related to age, educational level, diabetes treatment and nuclear opacity. The primary cause of blindness and visual impairment is cataract, followed by diabetic retinopathy. Conclusions: The prevalence of moderate or severe visual impairment and blindness in people with type 2 diabetes in Funing County is relatively high. Attention should be paid to the prevention of blindness in this population. (Chin J Ophthalmol, 2020, 56: 593-599).