Prevalence of diabetic retinopathy assessed using two-field mydriatic fundus photography

Abstract

This study assesses the prevalence of asymptomatic retinopathy and attempts to identify risk groups for its development in patients with type 1 and 2 diabetes mellitus (T1DM and T2DM). The study involved clinics from 5 cities in the Russian Federation and it included 367 patients with DM, 34.88% men and 65.12% women, aged 50.88±20.55 years. 34.88% of patients suffered from T1DM, 65.12% suffered from T2DM, the average duration of the disease was 9.02±7.22 years. 58.31% of patients had a history of arterial hypertension, 13.08% had a history of smoking. The primary endpoint was the frequency of detection of diabetic changes in the eye fundus of patients with T1DM and T2DM in general; the secondary endpoint - same but separately, and for T2DM patients depending on the duration of the disease. The exploratory endpoint was the assessment of the influence of various factors on the development of DR. The patients underwent visometry (modified ETDRS table), biomicroscopy, mydriatic fundus photography according to the «2 fields» protocol. The average detection rate of DR was 12.26%, primarily observed in patients with T2DM (13.81%), women (9.26%), in both eyes (8.17%). Among patients with DR, 26 (19.55%) had glycated hemoglobin (HbA1c) level exceeding 7.5% (p=0.002), indicating a direct relationship between this indicator and the incidence of DR. Logistic regression analysis showed that the duration of diabetes of more than 10 years has a statistically significant effect on the development of DR. In the modified model for odds estimation, the likelihood of developing DR is increased by the duration of DM for more than 10 years; increased blood pressure; HbA1c level >7.5%. The obtained results, some of which will be presented in subsequent publications, highlight the effectiveness of using two-field mydriatic fundus photography as a screening for DR.