A comparative study of corneal endothelial cell count in diabetics and nondiabetics in a tertiary care hospital in North Kerala

Background: Diabetes mellitus (DM) is a metabolic condition with numerous etiologies characterized by persistent hyperglycemia and abnormalities in metabolism of carbohydrates, fats, and proteins as a result of abnormalities in either insulin action or insulin secretion. Diabetes can lead to ocular problems that include diabetic retinopathy, corneal endothelial cell change, superficial punctate keratitis, recurrent corneal erosion, and persistent epithelial abnormalities. The prevalence of Type 2 diabetes has risen to a global pandemic level. Diabetes may cause corneal endothelial morphological alterations in average cell size, coefficient of variation, and a decrease in corneal ECD and hexagonality. Keratopathy is a significant consequence of diabetes mellitus. Changes in corneal findings are increased along with progression of diabetic retinopathy. In this study, we compared corneal endothelial cell count in diabetics and nondiabetics using noncontact, noninvasive specular microscopy to detect any clinically significant change. Aims and Objectives: To study corneal endothelial cell count in Type 2 DM patients and nondiabetic individuals and to assess morphological changes in corneal endothelium in Type 2 DM patients. Methods: This is a comparative, cross-sectional, hospital-based study conducted in the OPD of Ophthalmology, Malabar Medical College Hospital and Research Center, Kozhikode, in the year 2022 to 2023. The study population was selected by convenient sampling. Noncontact specular microscopy was done among already diagnosed Type 2 DM patients and nondiabetic individuals in the age group between 18 and 70 years. Data were collected from both eyes of the patient, and analysis was done using the observations in the right eye. All subjects underwent routine ocular evaluation and dilated fundus examination to rule out diabetic retinopathy. Results: In this study, 92 patients (50%) had Type 2 DM and 92 (50%) were nondiabetic, age-matched healthy individuals. In the diabetic group, 67.4% were aged 61–70 years, compared to 55.4% in the nondiabetic group. Diabetic patients had decreased corneal endothelial cell density and hexagonality but increased average cell size and coefficient of variation compared to nondiabetics. Diabetic retinopathy severity increased with higher HbA1c values and longer diabetes duration, correlating with decreased corneal endothelial cell density. Diabetic corneas showed increased polymegathism and pleomorphism, indicating a significant association between keratopathy and DM compared to nondiabetics. Conclusion: In the current scenario, all diabetic patients visiting the ophthalmology OPD for routine vision checkups should be evaluated for corneal morphological parameters—endothelial cell density, average cell size, coefficient of variation, and hexagonality—using a noncontact specular microscope, alongside a dilated fundus examination for diabetic retinopathy. Routine screening for diabetic keratopathy and DR aids in early detection and treatment.