Abstract
OBJECTIVE: To determine the prevalence of diabetic retinopathy (DR) and associated risk factors among rural and urban people diagnosed with type 1 or type 2 diabetes mellitus (PwDM) in southern China. DESIGN: This is a cross-sectional study. SETTING: The study was conducted at primary health centres from 2 September to the end of December 2019. PARTICIPANTS: All the 3646 PwDM being registered in Qujiang District, aged ≥18 years were informed, of whom 2677 attended the screening and were recruited. PRIMARY AND SECONDARY OUTCOME MEASURES: The presence of DR was determined by trained graders using criteria of the UK National Health Service Diabetic Eye Screening Programme. Multiple logistic regression analyses were used to assess potential risk factors for the presence of DR. RESULTS: The mean age of the participants (73.4% of the 3646 invited people) was 63.4 years (SD 10.1 years), 1503 (56.2%) were female, 1749 (65.3%) were rural residents, 1654 (71.0%) participants had glycated haemoglobin (HbA1c)≥6.5%, 1773 (66.3%) had high blood pressure and the median duration of diabetes mellitus (DM) was <5 years. Although half (52.0%) of these participants had brief (<5 years) exposure to DM, 831 (31.3%, 95% CI: 29.3 to 32.8%) had DR, among whom 412 (49.6%) had sight-threatening DR. Men (33.1%) had a significantly higher prevalence of any DR than women (29.4%, p<0.05). There were no significant differences in DR prevalence at any level between rural and urban residents. In multivariate regression models, risk factors for any DR were HbA1c>6.5% (OR=1.58, p<0.01), using insulin and antihyperglycaemic medications (OR=1.76, p<0.01), longer duration of DM and higher systolic blood pressure (OR=1.01 for each mm Hg, p<0.01). CONCLUSIONS: The high prevalence of DR, hyperglycaemia and high blood pressure highlight the need for better management of non-communicable diseases in China.