Evaluation of retinal structure and function in prediabetes

Area of Science:

• Ophthalmology
• Endocrinology
• Diabetic Retinopathy Research

Background:

• Type 2 diabetes (T2DM) is known to affect retinal structure and function.
• Prediabetes (preDM), a precursor to T2DM, has been less studied regarding its ocular manifestations.
• Identifying early retinal deficits in preDM is crucial for timely intervention.

Purpose of the Study:

• To evaluate retinal structure using optical coherence tomography (OCT) and retinal function via multifocal electroretinogram (mfERG) in individuals with preDM.
• To investigate the associations between retinal structure and function across varying levels of glucose dysfunction.
• To determine if retinal deficits occur before the diagnosis of T2DM.

Main Methods:

• 85 subjects were categorized into control, preDM, and T2DM groups based on HbA1c levels.
• Retinal function was assessed using mfERG (N1 and P1 latency/amplitude).
• Retinal structure was evaluated using OCT (macular thickness).
• Statistical analyses included ANOVA, corrected t-tests, and multivariate regression.

Main Results:

• A significant relationship was found between T2DM/preDM diagnosis and delayed N1 latency, reduced foveal thickness, and age.
• Borderline significant differences in P1 latency were observed between control and preDM/T2DM groups.
• The T2DM group had well-controlled HbA1c but elevated systolic blood pressure.

Conclusions:

• Combined structural and functional retinal changes offer an associative model for preDM and T2DM.
• Delayed N1 latency is strongly associated with both preDM and T2DM.
• N1 findings and decreased foveal thickness are additive indicators for ocular health in preDM.
• Longitudinal studies are recommended to track functional and structural changes in preDM and T2DM.