Corneal epithelial barrier function in diabetic patients.

Purpose: To evaluate the corneal epithelial barrier function in diabetic patients.

Methods: In 29 eyes of 29 diabetic patients and 55 eyes of 55 nondiabetic controls, corneal epithelial permeability to fluorescein was measured using an anterior fluorophotometer. The average fluorescein concentration in the central cornea was compared between diabetic patients and controls. Multiple regression analysis was used to assess the factors that affect corneal epithelial barrier function in diabetic patients.

Results: The average fluorescein concentrations in diabetic patients and nondiabetic controls were 44.1 +/- 25.3 ng/mL and 29.9 +/- 19.8 ng/mL (mean +/- SD), respectively (P = 0.0057, unpaired t test). An explanatory variable relevant to the impaired corneal epithelial barrier function was the serum hemoglobin A1c (HbA1c) concentration (standardized partial regression coefficient = 0.466, P = 0.0163).

Conclusions: The corneal epithelial barrier function is impaired in diabetic patients. Diabetic patients with higher serum HbA1c levels are more predisposed to impaired barrier function in the corneal epithelium.