Associations of glycated hemoglobin (HbA1c) level with central corneal and macular thickness in diabetic patients without macular edema

Abstract

Objectives: To determine the correlation between central corneal thickness (CCT) and central macularthickness (CMT), and fasting plasma glucose levels and HbA1c levels before diabetic macular edema (DME)in type 2 diabetes mellitus (DM) patients without diabetic retinopathy.Methods: Forty-four eyes of subjects diagnosed with type 2 DM, and 45 healthy control subjects participatedin this study. Detailed ophthalmologic examination was performed with all participants. CMT was measuredin both groups by Spectral-domain optical coherence tomography. CCT measurements were made with anEchoscan US-500 ultrasonic pachymeter. Blood biochemical tests for glycated hemoglobin (HbA1c) and fastingplasma glucose levels were run on all patients.Results: The results of the study showed that the mean CCT was significantly thicker in type 2 DM patients563.84 ± 33.25 μm than in the controls 550.13 ± 28.41 μm (p = 0.039). The mean of CMT was 231.27 ± 37.74μm in the study group and 225.38 ± 38.33 μm in the control group (p > 0.05). No relationship was foundbetween CCT and CMT and HbA1c level in the study and control groups.Conclusions: The mean CCT was significantly thicker in type 2 DM patients without diabetic retinopathy thanin the controls. The mean CMT is thicker in type 2 DM patients without diabetic retinopathy patients than inthe controls, but this difference was not statistically significant. Optical coherence tomography can be a perfectdetector for early detection of DME.