Homocysteine - vitamin combination without effect on recurrent stroke: According to observational studies, even a moderately raised homocysteine level is an independent risk factor for cardiovascular diseases. Pyridoxine, cobalamin and folic acid reduce the homocysteine level. In a Swiss study, the rate of revascularisation procedures because of restenosis after coronary angioplasty can be reduced by the vitamin combination (a-t 2002; 33: 95). In a recently published randomised American study, the effect of the vitamins on the recurrence rate after stroke was investigated. Out of 3.680 men and women with an average age of 66 years and a stroke not more than 120 days previously and an average homocysteine level of 13.4 µmol/l, 1.814 took 25 mg Pyridoxine, 0.4 mg cobalamin plus 2.5 mg folic acid daily in addition to standard therapy. The control group received the combination in lower dosage (200 µg Pyridoxine, 6 µg cobalamin and 20 µg folic acid). The primary end point was the rate of recurrent ischaemic stroke. The homocysteine level was reduced by 2 µmol more in the high-dose group than in the low-dose group. However, there was no effect on the rate of stroke: with high-dose vitamins 152 (8.4%) of 1.814 participants suffered a relapse within an average of 20 months compared to 148 (8.1%) of 1.835 on low-dose vitamins. There were also no significant differences in the secondary end points of coronary events (6.3% versus 6.7%), deaths (5.4% versus 6.3%) and a combined end point of ischaemic stroke, coronary complications or death (16.7% versus 17.2%) (TOOLE, J.F. et al.: JAMA 2004; 291: 565-75). A Netherlands study which investigated 0.5 mg folic acid in 593 patients with stable coronary heart disease also arrived at a negative result. A combined end point of mortality and vascular complications occurred in 10.3% in the folic acid arm compared to 9.6% in the control group (LIEM, A. et al.: J. Am. Coll. Cardiol. 2003; 41: 2105-13). According to a study that has not yet been published in full (FACIT*) of 636 patients following stent implantation, the vitamin combination seems to have a significantly worse effect on restenosis rates and cardiac events than placebo (LOOK, M.: Arzneiverordnung in der Praxis 2003; 30: 9-10). With the current state of knowledge, the vitamin combination cannot be recommended in the secondary prophylaxis of atherosclerotic diseases -ed.

FACIT = Folate After Coronary Intervention Trial