Raised plasma homocysteine as a risk factor for retinal vascular occlusivedisease

Background/aims-A moderately elevated plasma concentration of the sulphur a mino acid homocysteine is an independent risk factor for atherosclerotic va scular disease. Many of the risk factors associated with coronary, cerebral , and peripheral atherosclerotic vascular disease are common to retinal vas cular occlusive disease but it is unclear whether elevated plasma concentra tions of homocysteine are also associated with such disease. This study ass essed the relation between retinal vascular occlusive disease and elevated levels of plasma total homocysteine (tHcy). Methods-A retrospective case-control study involving hospital based control s and cases with retinal artery, central retinal vein (including hemiretina l vein), and branch retinal vein occlusions was performed. The relation bet ween elevated tHcy, defined as a level greater than or equal to 12 mu mol/l and risk of retinal vascular occlusive disease was examined. Results-87 cases of retinal vascular occlusive disease including 26 cases o f retinal artery occlusion, 40 cases with central retinal vein occlusion, a nd 21 cases of branch retinal vein occlusion were compared with 87 age matc hed controls. Mean tHcy levels were higher in all disease groups and this d ifference was significant in patients with retinal artery occlusions (p = 0 .032) and patients with central retinal vein occlusion (p = 0.0001). When a djusted for known cardiovascular risk factors, tHcy was an independent risk factor for retinal vascular occlusive disease (OR 2.85 (95% CI 1.43-5.68)) . Conclusions-Elevated tHcy is an independent risk factor for retinal vascula r occlusive disease. Assessment of tHcy may be important in the investigati on and management of patients with retinal vascular occlusive disease.