Serum Cholinesterases, Paraoxonase, and Cardiovascular Risk After Intravitreal Bevacizumab

Bevacizumab, an anti-VEGF (vascular endothelial growth factor) agent used in the treatment of diabetic retinopathy and macular edema associated with retinal vein occlusion, is commonly administered in ophthalmology clinics through intravitreal injection. The systemic use of bevacizumab has been associated with serious conditions such as thromboembolism and bleeding. Although intravitreal bevacizumab is administered in smaller amounts and has limited systemic circulation, it requires repeated injections over a long period. These long-term intravitreal anti-VEGF therapies may lead to adverse outcomes, particularly thromboembolism, due to systemic inhibition of VEGF. However, limited information is available regarding the potential effects of this treatment on the systemic and cardiovascular systems. To evaluate this risk, the study aims to assess changes in the activities of paraoxonase 1 (PON1), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE), which are closely associated with lipid metabolism, coronary artery disease, and atherosclerosis. These enzymes are known biomarkers of cardiovascular health and play significant roles in protection against oxidative stress and inflammation. For this purpose, a case-control study is planned. Serum BChE and PON1 activities, as well as triglyceride (TG)/high-density lipoprotein (HDL) and TG/glucose ratios, will be determined in patients receiving repeated intravitreal bevacizumab injections and in control groups, and cardiovascular disease risk will be assessed. This study may help us better understand the safety profile of this treatment by revealing the effects of bevacizumab on serum enzyme activities and cardiovascular risk factors. These findings could contribute to optimizing treatment strategies in clinical practice.