Prevalence and risk factors of diabetic retinopathy in patients with type 2 diabetes in Shanghai

Aim To investigate the prevalence of diabetic retinopathy (DR) in residents of Shanghai and analyze the risk factors of DR. Methods This study involved 7233 patients with diabetes in 2016. The demographic data of the participants were collected using a questionnaire survey. Physical examination, laboratory tests, and ophthalmological examinations were conducted. Two professional ophthalmologists diagnosed and graded DR by fundus examination and then combined the results with fundus images. The unconditional multivariate Logistic regression analysis was used to determine the risk factors. Results In total, 6978 patients with type 2 diabetes in Shanghai with a mean age of 68.33±8.40y were recruited, including 2975 males (42.6%) and 4003 females (57.4%). Overall, 1184 patients were diagnosed with DR, with a prevalence rate of 16.97%. Regression analysis showed that duration of diabetes (OR 1.061, 95%CI 1.049-1.073), high systolic blood pressure (SBP; OR 1.071, 95%CI 1.037-1.106), increased glycosylated hemoglobin level (OR 1.234, 95%CI 1.162-1.311), high blood glucose level (OR 1.061, 95%CI 1.023-1.099), increased neutrophil-to-lymphocyte ratio (NLR; OR 1.132, 95%CI 1.053-1.217) and mean platelet volume (MPV; OR 1.077, 95%CI 1.016-1.142) were risk factors of DR. Conversely, hematocrit (HCT; OR 0.971, 95%CI 0.954-0.988) and mean corpuscular volume (MCV; OR 0.980, 95%CI 0.965-0.994) were protective factors. Conclusion The prevalence rate of DR in Shanghai is 16.97%. The duration of diabetes, high SBP, increased glycosylated hemoglobin, NLR, and MPV were determined as risk factors of DR.