Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT00005130 |
| Other study ID # |
1000 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
May 25, 2000 |
| Last updated |
April 12, 2016 |
| Start date |
January 1984 |
| Est. completion date |
September 2008 |
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 changes in coronary heart disease risk factors in cohorts of Black and white
males and females 18 to 30 years of age at baseline. Also, to identify life styles during
this age span which influence these changes in risk factors.
Description:
BACKGROUND:
Both epidemiologic and clinical research in coronary heart disease have increased our
awareness that some risk factors for disease such as obesity, hypertension, and
hypercholesterolemia may be partially determined by genetic factors or habits which are
formed in infancy, childhood, and adolescence. Studies to date also suggest that some of the
coronary heart disease risk factors do not change dramatically before the late teenage years
and that differences in characteristics by sex or race are most pronounced after this time.
However, relatively little work has been done to identify the characteristics of young adult
life which may be precursors to or coincident with the increase in risk factors prior to
middle age. While major increases in certain risk factors occur in young adulthood in
conjunction with significant changes in life style, the interrelationships among these risk
factors and changes have not been rigorously investigated.
Cross-sectional data, for example, suggest that weight gain is pronounced during the late
teens through age 30, particularly in males, and that a linear relationship exists between
weight and lipoprotein fractions at these ages. The reasons for and consequences of this
increase in adiposity need further investigation. The interaction of life events, behavior,
and changes in physical activity and dietary intake that may influence weight gain and
lipoprotein levels should be determined, as well as the importance of weight gain in
relationship to risk factor changes during this age span.
Investigators have examined the consistency of blood pressure levels in children to
determine whether "tracking" occurs into the teenage years. The results of these studies
have raised other interesting and important questions. Is there evidence for "tracking" of
other coronary risk factors? Does "tracking" persist into young adult life, a time during
which dramatic changes in life style are often taking place? The study will contribute to
our understanding of the development of atherosclerosis and will help to determine an
optimal strategy for prevention before individual life style patterns become well
established. The Working Group on Heart Disease Epidemiology in 1978 recommended the study
with highest priority. The study was approved by the National Heart, Lung, and Blood
Advisory Council in November 1982. The Request for Proposals was released in December 1982.
DESIGN NARRATIVE:
CARDIA, which began recruitment in 1985, has completed 7 examinations over 20 years in a
cohort of 5,115 men and women aged 18-30 years in four communities. Participants were
initially sampled from the total population, selected census tracts or, in the case of one
center, the membership of a large health plan. The original cohort had approximately equal
representation by blacks and whites, men and women, those aged 18-24 and 25-30, and those
with no more than a high school education and more than a high school education. The
baseline examination (Year 0) was conducted over a 14-month period during 1985-86. The
examination consisted of questionnaires on sociodemographic characteristics, health
behaviors, and psychological factors; an exercise treadmill test; resting
electrocardiography; a diet history assessment; anthropometry; pulmonary function testing;
and resting blood pressure. Fasting blood measurements included total cholesterol and its
subfractions, insulin, glucose, liver enzymes and other serum chemistry measurements, and
hematology.
Six additional examinations have been completed every 2-5 years, including a Year 20
examination completed in 2006. Repeat measurements on traditional risk factors, including
plasma lipids, blood pressure, anthropometry, smoking behavior, physical activity, and
pulmonary function testing (except Years 7 and 15) have used the same methods at each
examination to assess age and secular trends in these factors during young adulthood. In
selected years, additional measurements have been made, including a treadmill exercise test
at baseline and Year 7; diet history at baseline, Year 7, and Year 20; cardiovascular
reactivity measurements in Year 2; echocardiography and ambulatory blood pressure monitoring
(in a subset) at Year 5; skin reflectance and assessment of the experience of discrimination
and other psychosocial measures and urine sodium and creatinine in Year 7; echocardiography
(in a subset) in Year 10, glucose tolerance testing, and microalbuminuria in Year 10 and
Year 20; coronary CT scan in Year 15 and Year 20; and carotid intima media thickness in Year
20.
Retention of the surviving cohort was 90, 86, 81, 79, 74, and 72 percent at each of the
respective follow-up examinations. Cohort members are contacted every six month to obtain
information on vital status and current residence. Every other six-month contact also
includes speaking with the participant to ascertain information on current smoking status,
major illness or injury, and hospitalizations.
The Year 25 examination began June, 2010 and will continue through May, 2011. There will be
an estimated 3,525 participants from four field centers that will participate in the five
hour examination. The study ends in 2013.
