Homocysteine: a risk factor for retinal venous occlusive disease.

Purpose: Recent studies have shown a relationship between elevated levels of homocysteine and vascular disease including cerebrovascular accidents and myocardial infarctions. We evaluated patients with a recent retinal vein occlusion to determine if there was an associated elevation of homocysteine.
Design: Age and gender matched case-controlled study.
Participants: Twenty patients with retinal venous occlusive disease within the previous 6-month period and 40 control patients without retinal venous occlusive disease were enrolled in the study.
Methods: Twenty patients with a history of retinal vein occlusion underwent laboratory testing to determine serum homocysteine levels. In addition, a health survey was completed and several laboratory tests relating to vascular disease including cholesterol were checked. Two control groups were selected. The first group included patients with diabetes and no history of retinal vascular occlusive disease. The second control group included nondiabetic patients who also had no prior history of retinal vascular occlusive disease.
Main Outcome Measures: The main parameter measured in this study is fasting homocysteine.
Results: Fifteen of 20 patients (75%) with retinal vein occlusion disease had an elevated fasting serum homocysteine level, whereas only 5 of 40 control patients (13%) had an abnormal homocysteine level (P < 0.0005).
Conclusions: Patients with retinal venous occlusive disease have higher levels of homocysteine, which may serve as a modifiable risk factor.