Levels of Oxidized Low-Density Lipoprotein and High Sensitive C-Reactive Protein in Retinal Vascular Occlusions: A Pilot Study

Background: Oxidized low-density lipoprotein (OX-LDL) is believed to be a key trigger factor in the genesis of atherosclerosis. It has been postulated that it can activate inflammatory mediators such as high sensitive C-reactive protein (hs-CRP), interleukin 6 (IL6), and tumour necrosis factor (TNF). These mediators have been demonstrated to have an atherogenic effect.

Aims: This pilot study examined levels of OX-LDL and hs-CRP in patients with retinal vascular occlusive disorders.

Methods: We enroled 7 patients with retinal vascular occlusions during a two-month period. A high sensitive CRP of greater than 3mg/l was considered significantly elevated and a median oxidised LDL value greater than 59 U/L was considered significantly elevated.

Results: There were 4 cases of retinal vein occlusion, 1 case of amaurosis fugax, 1 case of cilioretinal artery occlusion and a case of cholesterol embolus in the retinal vasculature. Mean OX-LDL (55.6±21.1 U/L) was borderline, but within the normal range (<59 U/L) but hs-CRP (3.9±3.1 mg/l) were elevated compared to the normal range (0 -3 mg/l). Oxidized LDL was elevated in three patients (43%), and bordeline (between 55 and 59 U/L) in two patients (28%). No significant correlation was found between hs-CRP and OX-LDL values (Pearson’s correlation: r = 0.256; p = 0.456).

Conclusion: This study is the first to suggest that OX-LDL and hs-CRP may be elevated in retinal vascular disease. Further investigations are required to determine the significance of these findings.