Influence of high homocysteine and low folate plasmatic levels in medium-term prognosis after acute coronary syndromes.
ABSTRACT To test prospectively whether moderate hyperhomocysteinemia and low folate levels could have an influence in the prognosis of 155 patients who presented with an acute coronary syndrome.
After a mean follow-up of 13.4+/-7.4 months, patients with low folate levels had higher percentages of cardiovascular death and major cardiovascular events (33% vs. 5%, p<0.001; 44% vs. 22%, p<0.05) and patients with high homocysteine levels had a higher percentage of major cardiovascular events (31% vs. 14.5%, p<0.03). Kaplan-Meier survival estimates analysis showed that patients with low folate levels had a significantly higher probability of cardiovascular death and lower free-of-events survival (log rank statistic: 21.17, p<0.001 and 6.59, p=0.01). Patients with high homocysteine levels had a lower free-of-events survival (log rank statistic: 4.95, p=0.02). Different survival multivariate analysis model showed that the presence of low folate levels was an independent predictor of cardiovascular death (hazard ratio 8.85, 95% confidence interval 2.6-29.3, p<0.000) and high homocysteine levels was identified as independent predictor of major cardiovascular events (hazard ratio 2.34, 95% confidence interval 1.07-5.12, p<0.03).
Low folate levels and moderate hyperhomocysteinemia were identified as independent predictors of cardiovascular events in the follow-up.
- The American Journal of Cardiology 10/2002; 90(5):536-9. · 3.43 Impact Factor
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ABSTRACT: Increased levels of the physiological amino acid homocysteine (Hcy) are considered a risk factor for vascular disease. Hyperhomocysteinemia causes an intense remodelling of the extracellular matrix in arterial walls, particularly an elastolysis involving metalloproteinases. We investigated the activation of the latent elastolytic metalloproteinase proMMP-2 (72 kDa) by Hcy. Hcy was proved to exert a dual effect, activating proMMP-2 at low molar ratio (MR 10:1) and inhibiting active MMP2 at high molar ratio (MR > 1000:1). Methionine and the disulphide homocystine did not activate nor inhibit MMP-2, showing that the activation as well as the inhibition requires the thiol group to be free. The activation of proMMP-2 by Hcy is in accordance with the "cysteine-switch" mechanism, but occurs without further autoproteolysis of the enzyme molecule. In contrast with Hcy, the other physiological thiol compounds cysteine and reduced glutathione did not activate proMMP-2. These results suggest that the direct activation of proMMP2 by Hcy could be one of the mechanisms involved in the extracellular matrix deterioration in hyperhomocysteinemia-associated arteriosclerosis.Biochemical and Biophysical Research Communications 10/1999; 263(2):498-503. · 2.28 Impact Factor
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ABSTRACT: Homocysteine is a risk factor for cardiovascular disease. We evaluated the efficacy of homocysteine-lowering treatment with B vitamins for secondary prevention in patients who had had an acute myocardial infarction. The trial included 3749 men and women who had had an acute myocardial infarction within seven days before randomization. Patients were randomly assigned, in a two-by-two factorial design, to receive one of the following four daily treatments: 0.8 mg of folic acid, 0.4 mg of vitamin B12, and 40 mg of vitamin B6; 0.8 mg of folic acid and 0.4 mg of vitamin B12; 40 mg of vitamin B6; or placebo. The primary end point during a median follow-up of 40 months was a composite of recurrent myocardial infarction, stroke, and sudden death attributed to coronary artery disease. The mean total homocysteine level was lowered by 27 percent among patients given folic acid plus vitamin B12, but such treatment had no significant effect on the primary end point (risk ratio, 1.08; 95 percent confidence interval, 0.93 to 1.25; P=0.31). Also, treatment with vitamin B6 was not associated with any significant benefit with regard to the primary end point (relative risk of the primary end point, 1.14; 95 percent confidence interval, 0.98 to 1.32; P=0.09). In the group given folic acid, vitamin B12, and vitamin B6, there was a trend toward an increased risk (relative risk, 1.22; 95 percent confidence interval, 1.00 to 1.50; P=0.05). Treatment with B vitamins did not lower the risk of recurrent cardiovascular disease after acute myocardial infarction. A harmful effect from combined B vitamin treatment was suggested. Such treatment should therefore not be recommended. (ClinicalTrials.gov number, NCT00266487.).New England Journal of Medicine 05/2006; 354(15):1578-88. · 54.42 Impact Factor