ASSOCIATIONS BETWEEN DYSGLYCEMIA, RETINAL NEURODEGENERATION, AND MICROALBUMINURIA IN PREDIABETES AND TYPE 2 DIABETES

Purpose: To explore the association between retinal neurodegeneration and metabolic parameters in progressive dysglycemia. Method: A cross-sectional study was performed on 68 participants: normal glucose tolerance (n = 23), prediabetes (n = 25), and Type 2 diabetes without diabetic retinopathy (n = 20). Anthropometric assessment and laboratory sampling for HbA1c, fasting glucose, insulin, c-peptide, lipid profile, renal function, and albumin-to-creatinine ratio were conducted. Central and pericentral macular thicknesses on spectral domain optical coherence tomography were compared with systemic parameters. Results: Baseline demographic characteristics were similar across all groups. Cuzick's trend test revealed progressive full-thickness macular thinning with increasing dysglycemia across all three groups (P = 0.015). The urinary albumin-to-creatinine ratio was significantly correlated with full-thickness superior (R = -0.435; P = 0.0002), inferior (R = -0.409; P = 0.0005), temporal (R = -0.429; P = 0.003), and nasal (R = -0.493; P < 0.0001) pericentral macular thinning, after post hoc Bonferroni adjustment. There was no association between macular thinning and waist circumference, body mass index, blood pressure, lipid profile, or insulin resistance. Conclusion: Progressive dysglycemia is associated with macular thinning before the onset of visible retinopathy and occurs alongside microalbuminuria. Retinal neurodegenerative changes may help identify those most at risk from dysglycemic end-organ damage.