Background: Retinal artery occlusion (RAO) and retinal vein occlusion (RVO) are common causes of severe visual loss and several atherothrombotic risk factors such as hyperlipidemia, diabetes mellitus and arterial hypertension have been associated with these ophthalmic lesions.
Methods: In this retrospective study we investigated 66 patients with RAO, 87 patients with RVO and 405 age- and gender-matched control subjects. Lipoproteins were separated using an ultracentrifugation-precipitation method (beta-quantification) and the levels of lipids and apolipoproteins in VLDL, LDL and HDL particles were measured.
Results: After adjusting for the type of occlusion and lipid-lowering medication, patients with RVO and RAO versus controls had significantly higher levels of LDL-cholesterol (3.82+/-1.06, 3.59+/-0.90 and 3.07+/-0.83 mmol/L), LDL-triglycerides (0.39+/-0.14, 0.40+/-0.12 and 0.35+/-0.14 mmol/L) and apolipoprotein B (1.06+/-0.27, 1.05+/-0.26 and 0.84+/-0.21 g/L) in the LDL fraction, respectively. In RAO, LDL-triglycerides were independently associated with retinal vascular occlusion. Interestingly, apolipoprotein AI was elevated in both patient groups compared to controls. The most striking differences were found in lipoprotein(a) where both RVO and RAO patients had significantly higher levels than the control subjects (median values: 320, 290 and 130 mg/L, respectively).
Conclusion: These findings suggest that disorders in lipoprotein metabolism may contribute to the etiology of retinal vascular occlusions.