Different retinopathy phenotypes in type 2 diabetes predict retinopathy progression

Area of Science:

• Ophthalmology
• Endocrinology
• Diabetic Retinopathy Research

Background:

• Diabetic retinopathy (DR) is a leading cause of vision loss in type 2 diabetes.
• Mild nonproliferative diabetic retinopathy (NPDR) encompasses various phenotypes with potentially different progression rates.
• Understanding these phenotypes is crucial for predicting DR severity and guiding treatment.

Purpose of the Study:

• To characterize the progression of retinopathy severity across different phenotypes of mild NPDR in patients with type 2 diabetes.
• To identify specific clinical and ocular factors associated with DR progression in these phenotypes.

Main Methods:

• A 5-year longitudinal study followed type 2 diabetes patients with mild NPDR (ETDRS 20 or 35).
• Examinations included color fundus photography (CFP) and optical coherence tomography (OCT/OCTA).
• Phenotypes were classified by microaneurysm turnover (MAT) and central retinal thickness (CRT); Phenotype A (low MAT, normal CRT), Phenotype B (low MAT, increased CRT), Phenotype C (high MAT, +/- increased CRT).

Main Results:

• Significant differences in DR progression were observed between phenotypes (p < 0.001).
• Phenotype C showed a substantially higher risk of 2-or-more-step worsening (23.2%) compared to Phenotype A (3%) and Phenotype B (0%).
• DR progression correlated with HbA1c, LDL levels, MAT, MA formation/disappearance rates, and capillary closure (lower vessel density on OCTA).

Conclusions:

• Distinct DR phenotypes in type 2 diabetes exhibit varying risks of retinopathy progression.
• Phenotype C is strongly associated with increased HbA1c and a significantly higher likelihood of DR severity worsening.
• These findings highlight the importance of phenotype-specific risk assessment for managing diabetic retinopathy.