Delayed Visual Evoked Response is Linked to Vascular Endothelial Growth Factor and Autonomic Dysfunction in Type 2 Diabetes Mellitus

Abstract

Aims: In this study, we aimed to assess the link between visual evoked potentials (VEP), angiogenic marker (VEGF) and autonomic function tests in type-2 diabetes mellitus (T2DM). Methods: Age-matched 86 male subjects (44 type-2 diabetics on treatment and 42 normal healthy volunteers) were recruited for this study. Body mass index (BMI), basal cardiovascular parameters, spectral analysis of heart rate variability (HRV), were assessed. Fasting blood glucose, insulin, HOMA-IR and VEGF were estimated. The independent association of the P100 latency of VEP with VEGF was determined by multiple regression analysis. Results: LF-HF ratio a marker of sympathovagal balance, increased significantly (p=0.0287) in diabetic group compared to the control group. Comparison of visual evoked potentials between controls and diabetic groups showed significant increase in latency of P100 of both the eyes (right eye p<0.0001, left eye p=0.0003) among the cases. There was significant increase (p=0.0091) in VEGF in diabetic subjects when compared to control. Also positive and significant correlation of P100 latency of VEP with VEGF is seen in diabetics. Conclusions: There is delayed latency of VEP and increased VEGF in type 2 diabetic people. The correlation between VEP and VEGF could indicate the probable role of angiogenesis leading to reduced integrity of the neural pathways in T2DM.