Estimation of protein C and lipid levels in patients with retinal vein occlusive diseases

Abstract

Background: Retinal vein occlusion (RVO) is the second most common retinal vascular disorder after diabetic retinopathy, causing significant visual morbidity. It results from the obstruction of the retinal venous system, affecting either the central retinal vein or branch retinal veins. RVO manifests with characteristic features such as intraretinalhemorrhages, tortuous and dilated retinal veins, cotton wool spots, macular edema, and disc edema. Systemic risk factors like older age, hypertension, diabetes mellitus, hyperlipidemia, and coagulation abnormalities, particularly deficiencies in Protein C (PC) are associated with RVO. And contribute to vascular endothelial damage and thrombosis.

Objective: To estimate the levels of Protein C and lipids in patients with retinal vein occlusive diseases (RVOD).

Materials and Methods: This observational study was conducted over 12 months with 30 patients diagnosed with RVO attending the Ophthalmology department of SVRRGGH, Tirupati. Comprehensive ophthalmic and systemic histories were taken. Visual acuity, intraocular pressure, slit-lamp examination, and fundus examination were performed. Blood samples were collected after overnight fasting for estimating serum levels of, lipids and  Protein C using ELISA and chromogenic methods. Statistical analyses included unpaired t-tests and chi-square tests.

Results: The mean age of patients was 56.4 ± 13.7 years, with a slight male preponderance (53.3%). Fundus examination revealed CRVO in 20% of eyes, and BRVO in 46.7%. Significantly lower Protein C levels were found in patients with CRVO and BRVO (p<0.05).. Lipid analysis showed significantly higher LDL and total cholesterol and lower HDL in CRVO patients compared to those with IT BRVO and ST BRVO (p<0.05).

Conclusion: The study found significant associations between lower Protein C levels and elevated LDL and total cholesterol with different forms of RVOD, particularly CRVO. These findings suggest that monitoring and managing Protein C and lipid levels could be crucial in understanding and mitigating the progression of RVOD.