Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT00005131 |
| Other study ID # |
1001 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
May 25, 2000 |
| Last updated |
April 12, 2016 |
| Start date |
July 1985 |
| Est. completion date |
January 2007 |
Study information
| Verified date |
April 2009 |
| Source |
National Heart, Lung, and Blood Institute (NHLBI) |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
United States: Federal Government |
| Study type |
Observational
|
Clinical Trial Summary
To measure associations of established and suspected coronary heart disease risk factors
with both atherosclerosis and new coronary heart disease events in representative cohorts
from four diverse United States communities. To compare the communities with respect to risk
factors, medical care, atherosclerosis, and coronary heart disease incidence. ARIC has two
components in each community: study of representative cohorts of adult men and women, and
community surveillance of morbidity and mortality.
Description:
BACKGROUND:
Although it is now firmly established that coronary heart disease mortality rates in the
United States have fallen by about 50 percent since the mid 1960's, there has been no
systematic program to study in parallel coronary heart disease morbidity and the prevalence
of atherosclerosis. Such information is essential for an understanding of the factors
influencing the time trends, for quantifying the effects of prevention versus treatment, and
for guiding future policy in research and services. It remains a possibility that the
mortality decline in past years was not accompanied by a reduction in incidence, or a
diminution in the extent of the underlying arterial diseases. A trend confined to mortality
would require different explanations and call for different strategies of prevention than a
decline encompassing the whole spectrum of clinical manifestations, which would favor a risk
factor explanation. ARIC surveillance provides cardiovascular incidence rates, and its
cohorts provide information on atherosclerosis, cardiovascular symptoms, new and established
risk factors and medical care utilization on representative residents of each community. New
predictors of both atherosclerosis and cardiovascular diseases are investigated using data
obtained at four examination centers, the ultrasound center and five central laboratories.
The 1978 Conference on the Decline in Coronary Heart Disease Mortality and the 1979 Working
Group on Heart Disease Epidemiology both recommended a community surveillance program. As a
result, in 1980 the Clinical Applications and Prevention Advisory Committee and the National
Heart, Lung, and Blood Advisory Council approved Phase I of the surveillance pilot study.
Phase II of the pilot study and the full-scale study was approved by the Clinical
Applications and Prevention Advisory Committee in May 1982. The Requests for Proposals for
ARIC were released in September 1984 and awards made in 1985.
DESIGN NARRATIVE:
ARIC is a large-scale, long-term program that measures associations of established and
suspected CHD risk factors with both atherosclerosis and new CHD events in men and women
from four diverse communities. The project has two components: community surveillance of
morbidity and mortality, and repeated examinations of a representative cohort of men and
women in each community. The representative cohorts include 4,000 persons from each
community. Three of these reflect the ethnic composition of the communities in which they
live; one cohort is black. The community surveillance involves abstracting hospital records
and death certificates and investigating out-of-hospital deaths for hospitalized myocardial
infarction and CHD death in 800,000 men and women in these four communities.
All cohort participants were examined four times (1987-90, and 1990-93, 1993-96, and
1996-99), and were contacted annually to update their medical histories. Atherosclerosis was
measured by carotid ultrasonography. Arteriosclerosis was measured using retinal
photography. Cerebrovascular disease was assessed using MRI in a sample of black and white
participants. Risk factors studied include: blood lipids, lipoprotein cholesterols, and
apolipoproteins; plasma hemostatic factors; blood chemistries and hematology and indicators
of infectious and inflammatory disease; DNA markers of these risk factors, sitting, supine
and standing blood pressures; anthropometry; fasting blood glucose and insulin levels; ECG
findings; heart rate variability; cigarette and alcohol use; physical activity levels;
dietary aspects; and family history. Novel factors are tested using nested case-control
studies on stored blood.
The fourth and final examination, which included a complete periodontal examination with
measures of inflammatory markers was completed in 1999, with a return rate of 86%. Community
surveillance currently provides complete age, race, and sex-specific rates of
hospitalization for myocardial infarction and coronary heart disease death in the
communities for 1987-1997.
The study has been extended through January, 2007 to continue to follow the cohort through
annual telephone calls and hospital surveillance to identify incident cardiovascular events
through 19 years. Community surveillance continues to identify trends in cardiovascular
disease incidence, case-fatality, and mortality in 35-74 year olds over a 19 year period.
The diverse communities can be compared with respect to CHD incidence and medical care and,
through the cohort component, with respect to risk factors and peripheral atherosclerosis.
The results will provide a measure of the variation in the distribution and determinants of
CHD in the U.S. and, within the limits of ecologic analysis, suggest possible reasons for
observed differences.
