Authors
Folsom AR. Nieto FJ. McGovern PG. Tsai MY. Malinow MR. Eckfeldt JH.
Hess DL. Davis CE.
Institution
Division of Epidemiology, School of Public Health, University of Minnesota,
Minneapolis 55454-1015, USA. folsom:epivax.epu.umn.edu
Title
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 [see comments].
Comments
Comment in: Circulation 1998 Jul 21;98(3):196-7
Source
Circulation. 98(3):204-10, 1998 Jul 21.
Abstract
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 prospective studies are needed. METHODS AND
RESULTS: We used a prospective 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 C677T mutation
of the methylenetetrahydrofolate reductase gene or with 3 mutations of the
cystathionine beta-synthase gene. CONCLUSIONS: Our
prospective 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. Randomized trials,
some of which are under way, are needed to better clarify the
interrelationships of tHcy, B vitamins, and cardiovascular
disease.