Plain English Summary
Background and study aims
Diabetic retinopathy is a diabetes complication that affects the eyes. The incidence and risk factors for diabetic retinopathy in southern China remain unclear. This study aims to explore the onset and progression of diabetic retinopathy and its determinants in South China.
Who can participate?
Type 2 diabetic patients registered in community health centres in Yuexiu district in Guangzhou, China
What does the study involve?
Comprehensive eye tests are performed annually for 5 years, as well as blood and urine tests.
What are the possible benefits and risks of participating?
Participants receive an annual comprehensive eye test and one-on-one ophthalmologist consultation based on the exam results. All the exams follow the normal clinical operation.
Where is the study run from?
Zhongshan Ophthalmic Center, Sun Yat-sen University (China)
When is the study starting and how long is it expected to run for?
November 2017 to October 2023
Who is funding the study?
National Natural Science Foundation of China
Who is the main contact?
Prof. Wenyong Huang
Dr Wei Wang
No. 54. Xianlie Nan Road
+86 (0)20 87334687
Ms Yuting Li
No. 54. Xianlie Nan Road
+86 (0)20 87334687
Guangzhou Diabetic Eye Study (GDES): exploring the onset and progression of diabetic retinopathy and the determinants in south China: a prospective cohort study
This project aims to explore the onset and progression of diabetic retinopathy (DR) and their determinants through a prospective cohort in South China.
Approved 25/10/2017, Zhongshan Ophthalmic Center Ethics Committee, Sun Yat-sen University (No.7 Jinsui Road, Zhujiang New Town, Guangzhou, China; +86 (0)20 87332529; firstname.lastname@example.org), ref: 2017KYPJ094
Community-based prospective cohort study
Primary study design
Secondary study design
Patient information sheet
Not available in web format, please use the contact details below to request a participant information sheet
Diabetic retinopathy screening among people with diabetes
The GDES is an ongoing community-based prospective cohort study that includes type 2 diabetic patients registered in the community health centres in Yuexiu district in Guangzhou. This district is one of the oldest and central areas of Guangzhou, the population is stable. The Zhongshan ophthalmic centre (ZOC), which is affiliated with Sun Yat-sen University in Guangzhou, is located in this district and is the main provider of eye health services for the city. The communities are stable and the community health centres have established long-term collaboration with ZOC and are fully equipped with a well-established registry system for diabetic patients. The participants were originally recruited in November 2017, and the plan was to follow up on them annually for 5 years. All ocular examinations were performed at ZOC. The examinations are as follows:
1. Visual acuity and refraction tests performed by qualified optometrists
2. Ocular biometric measurements
3. Intraocular pressure (IOP) measurement
4. Pupil dilation
6. Slit lamp and fundus examinations
7. Colour retinal photographs
8. Optical coherence tomography (OCT)
9. Questionnaire interview
10. Biological sample collection
Primary outcome measure
Prevalence, incidence and progression rates of DR, measured using grading of OCT results annually for 5 years
Secondary outcome measures
There are no secondary outcome measures
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Aged 35–85 years
2. Diagnosed type 2 diabetes confirmed by medical records from endocrinologists, insulin treatments, oral medicine, fasting blood glucose ≥7.0 mmol/L for at least two consecutive measurements or postprandial blood glucose ≥11.1 mmol/L
3. Ocular-treatment-naïve eyes
Target number of participants
Participant exclusion criteria
1. Any severe systemic disease, such as ischemic heart disease, stroke, cancer and kidney disease, or a history of systemic surgery, such as cardiac bypass, thrombolysis and kidney transplantation
2. Any cognitive disorder, mental disorder or failure to finish the questionnaire and all the examinations
3. Combined glaucoma, age-related macular degeneration, glaucoma, vitreous macular disease (vitreous haemorrhage, retinal detachment), amblyopia and other eye diseases
4. A history of intraocular surgery, such as retinal laser, intraocular anti-VEGF injection, glaucoma surgery, cataract surgery, laser myopia surgery and vitreoretinal surgery history
5. A failure of mydriasis due to corneal ulcer, severe refractive media turbidity or shallow anterior chamber and angle closure glaucoma
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Zhongshan Ophthalmic Center
Sun Yat-sen University No. 54 Xianlie Nan Road Yuexiu District
Sun Yat-sen University
Funding Body Type
private sector organisation
Funding Body Subtype
Universities (academic only)
Results and Publications
Publication and dissemination plan
The results of the study will be presented as scientific article.
IPD sharing statement
The datasets generated during and/or analysed during the current study will be available upon request from Prof. Wenyong Huang (email@example.com). Informed consent will be obtained before the participant join the study. The study will follow the legal restrictions of the Ethics Committee of Zhongshan Ophthalmic Center, Sun Yat-sen University. For access to the data, please contact the principal investigator after the study completes.
Intention to publish date
Participant level data
Available on request
Basic results (scientific)