Longitudinal Neural and Microvascular Changes in Type 2 Diabetic Patients Without Retinopathy: A 2-Year Prospective...

Area of Science:

• Ophthalmology
• Endocrinology
• Neuroscience

Background:

• Type 2 diabetes mellitus (T2DM) is a systemic disease with significant ocular complications.
• Diabetic retinopathy (DR) is a major cause of vision loss in T2DM patients.
• Early detection of retinal changes in T2DM is crucial for timely intervention.

Purpose of the Study:

• To compare 2-year longitudinal changes in macular ganglion cell-inner plexiform layer thickness (GCIPLT) and superficial capillary plexus (SCP) vessel density.
• To assess these changes in T2DM patients without retinopathy (non-DR) versus healthy controls.

Main Methods:

• Prospective observational cohort study involving T2DM patients without retinopathy and age/sex-matched healthy controls.
• Macular GCIPLT, retinal thickness (RT), and SCP vessel density were measured at baseline and 2-year follow-up.
• Linear mixed-effects models were used to compare longitudinal changes between groups.

Main Results:

• Significant GCIPLT reduction occurred in the non-DR group (-0.229 µm/y), approximately 5-fold faster than in controls.
• Adjusted longitudinal rates showed accelerated RT and GCIPLT decline in non-DR patients compared to controls.
• No significant differences in longitudinal SCP vessel density changes were observed between the groups.

Conclusions:

• Neurodegenerative changes, indicated by GCIPLT thinning, may precede microvascular alterations in T2DM patients without retinopathy.
• Monitoring GCIPLT is essential for long-standing diabetes management, even in the absence of clinical retinopathy.