Abstract
Purpose:
To describe the age- and gender-specific prevalence, characteristics and 6 years’ progression of diabetic retinopathy (DR) in a rural population in northern China.
Methods:
6830 Han Chinese aged 30 years and older from 13 villages of Yongnian County, Handan city, Hebei province,were examined during the year 2006-2007. Participants were subsequently invited to attend 6-year follow-up exams in 2012. All participants underwent a standardized interview, a comprehensive eye examination and fasting blood glucose testing according to the American Diabetes Association diagnostic criteria (fasting plasma glucose ≥7.0 mmol/l). Retinal photographs obtained after pupil dilation were graded for presence and severity of DR according to the modified Early Treatment Diabetic Retinopathy Study (ETDRS) classification system.
Results:
Of the 6830 eligible individuals participating in the study, 5597 (81.9%) had fasting blood glucose results available. Of these, 387 (6.9%) participants were diagnosed with diabetes mellitus, including 247 newly diagnosed subjects (NDM) and 140 known diabetic subjects (KDM). The overall prevalence of DR was 43.1% (95% CI: 38.1, 48.4) and was higher in persons with KDM (65.2%) than NDM (33.5%). The prevalence of proliferative DR, macular edema and vision-threatening retinopathy were 1.6%, 5.2% and 6.3% respectively, with 12.1% with KDM having untreated vision-threatening DR. In multiple logistic regression models for all diabetic participants, independent risk factors for DR were longer duration of diabetes (OR 3.07, 95% CI:1.94, 4.85, per 5 years of duration), higher FPG levels (OR 1.17; 95% CI: 1.08, 1.27, per mmol/l increase) and higher systolic blood pressure (OR 1.22; 95% CI: 1.08, 1.37, per 10 mmHg increase). The 6-year incidence and progression of diabetic retinopathy are being analyzing now.
Conclusions:
Our study reports a high prevalence of DR among adults 30 years and older with diabetes in rural China. Based on estimates obtained from our study, we projected that in rural China, 21.1 million persons aged 30+ years have diabetes and 9.2 million have DR, including 1.3 million with vision-threatening DR. In rural Chinese persons with diabetes, longer diabetes duration, hyperglycemia and elevated blood pressure are risk factors for DR.There is a pressing need for appropriate screening and management of diabetes and its complications in rural China.
Keywords: 499 diabetic retinopathy •
498 diabetes •
463 clinical (human) or epidemiologic studies: prevalence/incidence