Prevalence and risk factors of diabetic retinopathy among Chinese adults with type 2 diabetes in a suburb of Shanghai, China

Abstract

Background To investigate the prevalence and risk factors of diabetic retinopathy (DR) in a Chinese population with type 2 diabetes mellitus (T2DM) in a suburb (Qingpu) of Shanghai, China. Methods A population-based cross-sectional study. A total of 7462 residents with T2DM in Qingpu were enrolled according to the resident health archives from January 2020 to December 2020. Blood and urine samples of the subjects were collected. Disc- and macula-centred retinal images were taken to assess DR. SPSS was used to analyse and investigate the prevalence and risk factors of DR. Results The fundus images of 6380 (85.5%) subjects were of sufficiently good quality for grading. The average (range) age of 6380 subjects was 63.46±7.77 (28–92) years. Six hundred forty-four subjects were diagnosed with DR. The prevalence of DR was 10.1% (95% CI 9.4%-10.8%), with mild, moderate, and severe non-proliferative retinopathy and proliferative retinopathy being 2.1%, 6.3%, 1.3% and 0.4%, respectively. The prevalence of bilateral DR was 6.5%. Higher T2DM duration (OR, 1.057), fasting plasma glucose (OR, 1.063), glycated hemoglobinA1c (OR, 1.269), urea nitrogen (OR, 1.059), and urinary albumin (OR, 1.001) were associated with the higher DR prevalence. Conclusion The prevalence of DR among Chinese adults with T2DM in Qingpu was 10.1%, in which non-proliferative DR was more common. Higher fasting plasma glucose and glycated hemoglobinA1c are well-known risk factors of DR, consistent with the findings in our study. Our study didn’t find the risk between lipid indicators and DR. However, several renal function indicators, like higher urea nitrogen and urinary albumin, were risk factors for DR in this study. Appropriate diagnosis and intervention should be taken in time to prevent and control DR development.

Diabetic retinopathy in China: Epidemiology, screening and treatment trends—A review

“…The common modifiable and non‐modifiable risk factors for DR and VTDR from studies conducted in China are summarised in Table 2. These studies indicated that classic risk factors including a longer duration of diabetes and poor control of blood glucose are the major risk factors for DR development 3,18–25,35,36,40–42 . Studies have reported a significantly higher risk of VTDR in patients with a DM duration of more than 15 years than in those with a duration of less than 5 years; however, lower odds ratios of disease duration were observed in patients who developed VTDR than in those who developed DR (Table 2).…”

“…These studies indicated that classic risk factors including a longer duration of diabetes and poor control of blood glucose are the major risk factors for DR development. 3,[18][19][20][21][22][23][24][25]35,36,[40][41][42] Studies have reported a significantly higher risk of VTDR in patients with a DM duration of more than 15 years than in those with a duration of less than 5 years; however, lower odds ratios of disease duration were observed in patients who developed VTDR than in those who developed DR (Table 2). One plausible explanation might be the less important role of the duration of DM than glycaemic control in forecasting progression from earlier to later stages of DR once retinopathy is already present.…”

“…7 The number of people affected by blindness or visual impairment due to DR was estimated to increase from 0.2 and 1.4 million in 1990, to 0.4 million and 3.2 million in 2020, respectively, accounting for 1.20% of all blindness and 1.49% of all moderate and severe vision impairment worldwide. 7,16 Although there is no reported national prevalence of DR in China yet, developing countries, including China, were previously considered to have a higher prevalence of DR. 17 Table 1 summarises the reported regional DR prevalence after 2000 and the related epidemiologic features, with the prevalence of DR ranging from 8.1% to 43.1% in patients with DM, [18][19][20][21][22][23][24][25][26][27][28][29][30][31] whereas the global estimate was 22.3%-34.6%. 32,33 The regional prevalence of DR among Chinese patients with known DM varied significantly from 10.1% to 65.2% (Table 1).…”

“…12,25,43 There is less agreement with DR development among studies in China concerning the importance of other factors, such as age, gender, education level, smoking status, alcohol consumption, insulin treatment and renal dysfunction in DR development. [18][19][20]22,24,25,29 Studies conducted in China have suggested a higher prevalence of DR in patients living in rural regions and with a lower educational background (Table 2). One study projected that in rural China, 21.1 million adults aged 30 years have diabetes and 9.2 million have DR, including 1.3 million patients with VTDR.…”

“…Although there is no reported national prevalence of DR in China yet, developing countries, including China, were previously considered to have a higher prevalence of DR 17 . Table 1 summarises the reported regional DR prevalence after 2000 and the related epidemiologic features, with the prevalence of DR ranging from 8.1% to 43.1% in patients with DM, 18–31 whereas the global estimate was 22.3%–34.6% 32,33 . The regional prevalence of DR among Chinese patients with known DM varied significantly from 10.1% to 65.2% (Table 1).…”