Retinal vein occlusion and hyperhomocysteinemia

Introduction: Previous studies have reported that an elevated plasma homocysteine level is a risk factor for vascular disease. The aim of this study is to determine whether hyperhomocysteinemia is a risk factor for retinal vein occlusion (RVO) and whether it is a prognostic factor. Patients and methods: The plasma homocysteine level was measured in 101 patients and compared to the plasma homocysteine level of controls. The relation between plasma homocysteine level and the other known risk factors of retinal vein occlusion was studied, as well as the correlation between the clinical outcome of the RVO and the plasma homocysteine level. Results: The mean plasma homocysteine level was significantly higher in the 101 RVO patients than in the 29 controls (11.9 mmol/l vs 8.6, p < 0.001). We found no relation between plasma homocysteine and other risk factors of vascular disease except for the hematocrit level. Hyperhomocysteinemia was more frequent in the ischemic forms and in bilateral RVO, but the difference was not statistically significant. Conclusions: Hyperhomocysteinemia seems to be an independent risk factor for RVO and was more frequent in severe RVO, but our study did not evidence an association with a severe prognosis. Vitamin therapy can decrease homocysteinemia but its efficacy in the prevention and in the treatment of RVO remains to be demonstrated.