Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT00083811 |
| Other study ID # |
1252 |
| Secondary ID |
R01HL069870 |
| Status |
Completed |
| Phase |
N/A
|
| First received |
June 2, 2004 |
| Last updated |
August 5, 2016 |
| Start date |
January 2004 |
| Est. completion date |
December 2008 |
Study information
| Verified date |
December 2008 |
| 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 investigate the role of genetics in cardiorespiratory fitness, obesity, and risk of
hypertension.
Description:
BACKGROUND:
Hypertension is a multifactorial disease with genetic and environmental factors contributing
to the disease process. HYPGENE will investigate gene-fitness and gene-obesity interactions
that relate to the development of hypertension during adulthood. The study uses the cohort
of the Aerobics Center Longitudinal Study (ACLS) at the Cooper Clinic.
DESIGN NARRATIVE:
The HYPGENE Study is a collaborative effort between the Pennington Biomedical Research
Center, the Cooper Institute, and Washington University in St. Louis. The aim of the study
is to investigate the contributions of DNA sequence variation in candidate genes as well as
their interactions with cardiorespiratory fitness and obesity to the risk of hypertension in
participants of the Aerobics Center Longitudinal Study (ACLS). In the first phase (as of
12/01/03), a group of 1000 subjects, who were normotensive and free of cardiovascular
disease and diabetes at the time of their first preventive medical examination (from 01/1987
to 02/2001) will be selected from the ACLS cohort. Half of these subjects (n=500) developed
hypertension during the follow-up period (duration 2 to 16 years), whereas the other half
remained normotensive. In the second phase (from 12/03 to 11/05), the sample size will be
increased to 1500 subjects (750 cases and 750 controls). Cases are defined as individuals
who were normotensive at baseline but developed essential hypertension during follow-up.
Comparison individuals are those who also were normotensive at baseline and remained
normotensive during follow-up. The ascertainment of the case-control status will be done
during the subjects' return visits to the Cooper Clinic. A panel of biallelic single
nucleotide polymorphisms in candidate gene loci will be typed. The candidate genes are
selected based on their putative roles in the physiological pathways pertaining to the
regulation of blood pressure by fitness and obesity, or on evidence of linkages and
associations in previous studies. The candidates include endothelial factors contributing to
vasodilation and vasoconstriction, beta-adrenergic receptors and their kinases, which
mediate the effects of autonomic nervous system on cardiac function and vascular tone, the
renin angiotensin system, and signaling molecules that mediate the effects of laminar shear
stress on vascular wall enzyme activity and gene expression. Logistic regression modeling
and classification and regression trees methodology will be used to analyze the contribution
of genotype, fitness level and obesity, as well as their interactions, to the risk of
hypertension. The HYPGENE study will produce novel data on the effects of genetic factors in
the presence of either high or low cardiorespiratory fitness level or obesity or normal body
weight on the development of hypertension. These data could ultimately lead to more
efficient use of physical activity and body weight control in the primary and secondary
prevention of hypertension.
