Does central corneal thickness correlate with haemoglobin A1c level and disease severity in diabetes type II?

Aim: To compare central corneal thickness (CCT) values of patients with type II diabetes mellitus with those of healthy subjects, and evaluate the effect of disease duration, retinopathy severity, and HbA1c level on CCT.Materials and methods: One hundred and twenty-six consecutive type II diabetic patients and 36 non-diabetic healthy subjects were included in the study. CCT was measured using the Orbscan II corneal topography system. The effect of disease duration, retinopathy severity, and HbA1c level on CCT was evaluated using analysis of variance (ANOVA) andthe independent sample t test. Results: CCT was significantly higher in diabetic patients than in non-diabetic subjects. Severity of retinopathy and disease duration had no apparent effect on CCT. Diabetic patients with HbA1c levels over 7% had thicker corneas than patients with HbA1c levels under 7% (P = 0.021).Conclusion: Type II diabetic patients have thicker corneas than non-diabetic subjects. Higher HBA1c level may be amarker for predicting the increase in CCT in patients with type II diabetes.