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Updated: Aug 6, 2026
10:03
A Zebrafish Model of Diabetes Mellitus and Metabolic Memory
Published on: February 28, 2013
Long-term glycaemic control and diabetic retinopathy
D R McCance1, D R Hadden, A B Atkinson
1Sir George E. Clark Metabolic Unit, Department of Ophthalmology, Queen's University, Belfast.
Lancet (London, England)
|October 7, 1989
Summary
Long-term blood sugar control, measured by glycosylated hemoglobin (HbA1), strongly correlates with diabetic retinopathy severity. Achieving near-normal HbA1 levels is crucial for preventing vision complications in diabetes patients.
Area of Science:
- Endocrinology
- Ophthalmology
- Diabetology
Background:
- Diabetic retinopathy is a leading cause of vision loss in patients with diabetes mellitus.
- The relationship between long-term glycemic control and the development/progression of diabetic retinopathy requires further elucidation.
Purpose of the Study:
- To investigate the correlation between mean serial glycosylated hemoglobin (HbA1) levels and the presence and severity of diabetic retinopathy.
- To assess the threshold of HbA1 associated with proliferative diabetic retinopathy.
Main Methods:
- Retinal photography was performed on 216 patients with insulin-dependent diabetes mellitus.
- Mean glycosylated hemoglobin (HbA1) levels were calculated from serial measurements taken every 3 months over 6 years.
- Patients were categorized based on the absence or presence of retinopathy (no retinopathy, background retinopathy, proliferative retinopathy).
Main Results:
- A significant correlation was observed between higher mean HbA1 levels and increased severity of diabetic retinopathy.
- Proliferative retinopathy was exclusively found in patients with mean HbA1 levels exceeding 10%.
- This association persisted even after accounting for the duration of diabetes.
Conclusions:
- Long-term glycemic control, as reflected by mean HbA1, is a critical factor in the development of diabetic retinopathy.
- Maintaining glycemic control as close to normal as possible is strongly recommended to mitigate the risk and progression of diabetic retinopathy.
- These findings underscore the importance of intensive diabetes management for preserving vision.
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