In this third up date of the Cochrane review , there were no differences in effects of homocysteine-lowering interventions in the form of supplements of vitamins B6 , B9 or B12 given alone or in combination comparing with placebo on myocardial infa rct ion , death from any cause or adverse events .
BACKGROUND Cardiovascular disease , which includes coronary artery disease , stroke and peripheral vascular disease , is a leading cause of death worldwide .
Homocysteine is an amino acid with biological functions in methionine metabolism .
A postulated risk factor for cardiovascular disease is an elevated circulating total homocysteine level .
The impact of homocysteine-lowering interventions , given to patients in the form of vitamins B6 , B9 or B12 supplements , on cardiovascular events has been investigated .
This is an up date of a review previously published in 2009 , 2013 , and 2015 .
OBJECTIVES To determine whether homocysteine-lowering interventions , provided to patients with and without pre-existing cardiovascular disease are effective in preventing cardiovascular events , as well as reducing all-cause mortality , and to evaluate their safety .
Prospective study of coronary heart disease incidence in relation to fasting total homocysteine, related genetic polymorphisms, and B vitamins: the Atherosclerosis Risk in Communities (ARIC) study.
BACKGROUND Elevated plasma total homocysteine ( tHcy ) , low B-vitamin intake , and genetic polymorphisms related to tHcy metabolism may play roles in coronary heart disease ( CHD ) . More prospect i ve studies are needed . METHODS AND RESULTS We used a prospect i ve case-cohort design to determine whether tHcy-related factors are associated with incidence of CHD over an average of 3.3 years of follow-up in a biracial sample of middle-aged men and women . Age- , race- , and field center-adjusted CHD incidence was associated positively ( P<0.05 ) with tHcy in women but not men , and CHD was associated negatively ( P<0.05 ) with plasma folate ( women only ) , plasma pyridoxal 5'-phosphate ( both sexes ) , and vitamin supplementation ( women only ) . However , after accounting for other risk factors , only plasma pyridoxal 5'-phosphate was associated with CHD incidence ; the relative risk for the highest versus lowest quintile of pyridoxal 5'-phosphate was 0.28 ( 95 % CI=0.1 to 0.7 ) . There was no association of CHD with the C677 T mutation of the methylenetetrahydrofolate reductase gene or with 3 mutations of the cystathionine beta-synthase gene . CONCLUSIONS Our prospect i ve findings add uncertainty to conclusions derived mostly from cross-sectional studies that tHcy is a major , independent , causative risk factor for CHD . Our findings point more strongly to the possibility that vitamin B6 offers independent protection . R and omized trials , some of which are under way , are needed to better clarify the interrelationships of tHcy , B vitamins  , and cardiovascular disease
In this third up date of the Cochrane review , there were no differences in effects of homocysteine-lowering interventions in the form of supplements of vitamins B6 , B9 or B12 given alone or in combination comparing with placebo on myocardial infa rct ion , death from any cause or adverse events .
BACKGROUND Cardiovascular disease , which includes coronary artery disease , stroke and peripheral vascular disease , is a leading cause of death worldwide .
Homocysteine is an amino acid with biological functions in methionine metabolism .
A postulated risk factor for cardiovascular disease is an elevated circulating total homocysteine level .
The impact of homocysteine-lowering interventions , given to patients in the form of vitamins B6 , B9 or B12 supplements , on cardiovascular events has been investigated .
This is an up date of a review previously published in 2009 , 2013 , and 2015 .
OBJECTIVES To determine whether homocysteine-lowering interventions , provided to patients with and without pre-existing cardiovascular disease are effective in preventing cardiovascular events , as well as reducing all-cause mortality , and to evaluate their safety .