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 .
Folic acid for the prevention of colorectal adenomas: a randomized clinical trial.
CONTEXT Laboratory and epidemiological data suggest that folic acid may have an antineoplastic effect in the large intestine . OBJECTIVE To assess the safety and efficacy of folic acid supplementation for preventing colorectal adenomas . DESIGN , SETTING , AND PARTICIPANTS A double-blind , placebo-controlled , 2-factor , phase 3 , r and omized clinical trial conducted at 9 clinical centers between July 6 , 1994 , and October 1 , 2004 . Participants included 1021 men and women with a recent history of colorectal adenomas and no previous invasive large intestine carcinoma . INTERVENTION Participants were r and omly assigned in a 1:1 ratio to receive 1 mg/d of folic acid ( n = 516 ) or placebo ( n = 505 ) , and were separately r and omized to receive aspirin ( 81 or 325 mg/d ) or placebo . Follow-up consisted of 2 colonoscopic surveillance cycles ( the first interval was at 3 years and the second at 3 or 5 years later ) . MAIN OUTCOME MEASURES The primary outcome measure was occurrence of at least 1 colorectal adenoma . Secondary outcomes were the occurrence of advanced lesions ( > or = 25 % villous features , high- grade dysplasia , size > or = 1 cm , or invasive cancer ) and adenoma multiplicity ( 0 , 1 - 2 , or > or =3 adenomas ) . RESULTS During the first 3 years , 987 participants ( 96.7 % ) underwent colonoscopic follow-up , and the incidence of at least 1 colorectal adenoma was 44.1 % for folic acid ( n = 221 ) and 42.4 % for placebo ( n = 206 ) ( unadjusted risk ratio [ RR ] , 1.04 ; 95 % confidence interval [ CI ] , 0.90 - 1.20 ; P = .58 ) . Incidence of at least 1 advanced lesion was 11.4 % for folic acid ( n = 57 ) and 8.6 % for placebo ( n = 42 ) ( unadjusted RR , 1.32 ; 95 % CI , 0.90 - 1.92 ; P = .15 ) . A total of 607 participants ( 59.5 % ) underwent a second follow-up , and the incidence of at least 1 colorectal adenoma was 41.9 % for folic acid ( n = 127 ) and 37.2 % for placebo ( n = 113 ) ( unadjusted RR , 1.13 ; 95 % CI , 0.93 - 1.37 ; P = .23 ) ; and incidence of at least 1 advanced lesion was 11.6 % for folic acid ( n = 35 ) and 6.9 % for placebo ( n = 21 ) ( unadjusted RR , 1.67 ; 95 % CI , 1.00 - 2.80 ; P = .05 ) . Folic acid was associated with higher risks of having 3 or more adenomas and of noncolorectal cancers . There was no significant effect modification by sex , age , smoking , alcohol use , body mass index , baseline plasma folate , or aspirin allocation . CONCLUSIONS Folic acid at 1 mg/d does not reduce colorectal adenoma risk . Further research is needed to investigate the possibility that folic acid supplementation might increase the risk of colorectal neoplasia . TRIAL REGISTRATION clinical trials.gov Identifier : NCT00272324
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 .