Correlation between severity of Type 2 diabetes mellitus and corneal morphology using specular microscopy in Indian population: A case–control study

Abstract

Context: Globally, there are 366 million patients living with Type 2 diabetes mellitus (DM), of which, 62.4 million are living in India alone. Thus, diabetic keratopathy is an important entity for all ophthalmologists. Aims: The study aims to identify variables associated with Type 2 DM, which correlate well with specular microscopy parameters. Settings and Design: This is a population-based case–control study aimed at determining the correlation between severity of DM Type 2 and corneal morphology. Subjects and Methods: After obtaining informed consent, detailed history of onset, duration, and treatment of Type 2 DM was ascertained. A comprehensive eye examination was done including specular microscopy using noncontact technique. Blood investigations were performed by the endocrine department for documenting whether disease was controlled or not. Statistical Tests: Unpaired t -test and linear regression analysis were used to determine the effects of multiple variables on the various specular microscopy parameters. Results: There were 100 eyes of diabetic patients with the mean age of 52.02 years, and 100 eyes of nondiabetic subjects with the mean age of 54.76. Short-term glycemic control parameter such as fasting blood sugar (FBS) and postlunch blood sugar (PLBS) showed no correlation with three specular microscopy parameters. However, HbA1c and severity of diabetic retinopathy influenced those parameters significantly. Conclusions: Corneal endothelium in diabetic patients was compromised, and it correlated well with the long-term glycemic control (HbA1c) but not with the short-term glycemic control (FBS, PLBS) or the duration of disease.