X-Message-Number: 27732
Date: Sat, 18 Mar 2006 19:45:12 -0800 (PST)
From: Doug Skrecky <>
Subject: B vitamins ineffective at lowering cardiovascular disease risk

[Homocysteine is a biomarker of cardiovascular disease, but unlike
cholesterol or blood pressure, does not help cause this disease.]

N Engl J Med 2006;354.
It will appear in the April 13 issue of the Journal.
March 12, 2006 (10.1056/NEJMoa055227)

Homocysteine Lowering and Cardiovascular Events after Acute
Myocardial Infarction

ABSTRACT

Background 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.

Methods 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.

Results 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).

Conclusions 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.


N Engl J Med 2006;354.
It will appear in the April 13 issue of the Journal.
March 12, 2006 (10.1056/NEJMoa060900)

Homocysteine Lowering with Folic Acid and B Vitamins in Vascular
Disease
The Heart Outcomes Prevention Evaluation (HOPE) 2 Investigators

ABSTRACT

Background In observational studies, lower homocysteine levels are
associated with lower rates of coronary heart disease and stroke.
Folic acid and vitamins B6 and B12 lower homocysteine levels.

Methods We randomly assigned 5522 patients 55 years of age or older
who had vascular disease or diabetes to daily treatment either with
the combination of 2.5 mg of folic acid, 50 mg of vitamin B6, and
1 mg of vitamin B12 or with placebo for an average of five years.
The primary outcome was a composite of death from cardiovascular
causes, myocardial infarction, and stroke.

Results Mean plasma homocysteine levels decreased by 2.4  mol per
liter (0.3 mg per liter) in the active-treatment group and increased
by 0.8  mol per liter (0.1 mg per liter) in the placebo group.
Primary outcome events occurred in 519 patients (18.8 percent)
assigned to active therapy and 547 (19.8 percent) assigned to
placebo (relative risk, 0.95; 95 percent confidence interval,
0.84 to 1.07; P=0.41). As compared with placebo, active treatment
did not significantly decrease the risk of death from cardiovascular
causes (relative risk, 0.96; 95 percent confidence interval,
0.81 to 1.13), myocardial infarction (relative risk, 0.98; 95 percent
confidence interval, 0.85 to 1.14), or any of the secondary outcomes.
Fewer patients assigned to active treatment than to placebo had a
stroke (relative risk, 0.75; 95 percent confidence interval,
0.59 to 0.97). More patients in the active-treatment group were
hospitalized for unstable angina (relative risk, 1.24; 95 percent
confidence interval, 1.04 to 1.49).

Conclusions Supplements combining folic acid and vitamins B6 and B12
did not reduce the risk of major cardiovascular events in patients
with vascular disease.

Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=27732