Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT00005482 |
| Other study ID # |
4969 |
| Secondary ID |
R01HL054711 |
| Status |
Completed |
| Phase |
N/A
|
| First received |
May 25, 2000 |
| Last updated |
February 8, 2016 |
| Start date |
September 1995 |
| Est. completion date |
March 1999 |
Study information
| Verified date |
June 2000 |
| Source |
University of Washington |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
United States: Federal Government |
| Study type |
Observational
|
Clinical Trial Summary
To test the hypotheses that the risk of myocardial infarction and/or stroke is associated
with elevated plasma levels of homocysteine, and low plasma levels of folate, vitamins B12
and B6.
Description:
BACKGROUND:
Elevated plasma homocyst(e)ine is a risk factor for vascular disease in middle-aged men.
Supplementation with folate, and to some extent vitamins B12 and B6, can reduce plasma
homocyst(e)ine levels. There is also evidence from in vitro studies that the adverse
atherogenic or thrombotic effects of Lp(a) may be greatly enhanced by homocyst(e)ine. The
high prevalence of low levels of folate and vitamins B12 and B6 among the elderly in the
United States has led to the hypothesis that a substantial portion of cardiovascular
morbidity and mortality among older persons could be prevented by increasing intake of these
nutrients to reduce plasma levels of homocysteine. Little is known, however, regarding the
relationship of homocysteine, folate, B vitamins, and Lp(a) to cardiovascular disease among
the elderly, among whom CVD represents the leading cause of morbidity and mortality.
DESIGN NARRATIVE:
In this ancillary study to the prospective Cardiovascular Health Study (CHS), a case-cohort
design was used to test hypotheses that the risk of myocardial infarction and/or stoke was
associated with elevated plasma levels of homocysteine, and low plasma levels of folate,
vitamins B12 and B6. Further, a determination was made whether elevated plasma levels of
homocysteine and Lp(a) interacted to increase substantially the risk of myocardial
infarction and/or stroke above that due to either factor alone. The sub-cohort was used to
study the relationship between the factors under study and progression of sub-clinical
atherosclerosis. For each case and sub-cohort member, an aliquot of fasting plasma drawn at
baseline was analyzed for homocysteine, folate B12, and B6 concentrations. [Values of plasma
Lp(a) were determined at baseline.] Results of these assays were combined with other CHS
data to address the hypothesis that the risk of myocardial infarction and/or stroke was
associated with elevated plasma levels of homocysteine, and low plasma levels of folate,
vitamins B12 and B6.
