Role of Visual Evoked Potential as a Screening Tool for Subclinical Optic Neuropathy in Patients with Diabetes Mellitus: A Cross-sectional Study

Introduction: Diabetes poses a major health challenge in India, with rising cases leading to serious complications like optic neuropathy and vision loss. These conditions often remain silent in the early stages, making timely detection crucial. Visual Evoked Potentials (VEPs), a simple non-invasive test, offer promise in identifying early optic nerve changes in diabetic patients and may improve outcomes through earlier intervention. Aim: To assess P100 latency and N75-P100 amplitude of VEP as a screening tool for detecting subclinical optic neuropathy in patients with Diabetes Mellitus (DM). Materials and Methods: This hospital-based cross-sectional study was conducted in the Department of Physiology in collaboration with the Department of Medicine at Shaheed Hasan Khan Mewati Government (SHKM) Government Medical College, Nalhar, Nuh, Haryana, India, from November 2022 to October 2023. A total of 240 subjects aged 18 to 60 years were enrolled, comprising 80 individuals with Type 1 Diabetes Mellitus (DM), 80 with Type 2 DM (case group) and 80 non diabetic individuals (control group). Participants were selected using a systematic random sampling method. The VEP test was performed and VEP parameters were compared between the case and control groups. Results: The mean age of the Type 1 DM, Type 2 DM and control groups was 26.61±6.71 years, 43.32±11.09 years and 30.7±11.23 years, respectively. Gender distribution showed that males comprised 53.75% of the Type 1 DM group, 60% of the Type 2 DM group and 70% of the control group. Females accounted for 46.25%, 40% and 30%, respectively. Analysis revealed a significant increase in P100 latency in both Type 1 diabetics (105.30±4.79 msec; p