Homocysteine and venous thrombosis: Outline of a vitamin intervention trial

In the past years several case-control studies established the association of an elevated plasma homocysteine concentration and the risk of venous thr omboembolism. It is still unclear if elevated homocysteine concentrations c an cause venous thrombosis. The VITRO (VItamins and ThROmbosis) trial is th e first multicenter, randomized, double-blind and placebo-controlled study to evaluate the effect of homocysteine-lowering therapy by means of 5 mg fo lic acid, 0.4 mg vitamin B-12 and 50 mg vitamin B-6. The study is a seconda ry prevention trial in 600 patients who suffered from a first episode elf i diopathic deep vein thrombosis (DVT) or pulmonary embolism (PE), or both. T here will be 300 hyperhomocysteinemic and 300 normohomocysteinemic patients included, all with an objectivated venous thrombosis. The end point is rec urrence of venous thrombosis.