Sociodemographic Regulation of Cardiovascular Function and Structure

To establish the aspects of ethnicity that are associated with the differential expression of cardiovascular disease processes in African Americans and Caucasian Americans twin children.

Study Overview

Detailed Description

BACKGROUND:

Given increasing awareness of the extent to which environments typically faced by ethnic groups differ, environmental influence on these processes may be an important factor that is an aspect of ethnicity. Socioeconomic status (SES) is a useful index of such environments and is associated with cardiovascular disease (CVD). Since behavior is one pathway through which SES influences are thought to be expressed in disease, this study focuses specifically on stress responsivity, which is thought to be linked to the pathophysiology of CVD. Since such disease has its antecedents in childhood, a multiethnic pediatric sample is employed. In addition, the subject sample consists of twins. Investigation of the impact of environments on the expression of CVD can be achieved only with proper control for biological influences.

DESIGN NARRATIVE:

Subjects completed three laboratory stressors: a video game task, a structured social interview, and the cold pressor. Stress responsivity was assessed, with particular interest being paid to systemic vascular resistance (SVR). Left ventricular mass (LVM) was also assessed. Sophisticated environmentally and genetically informative analyses permitted quantification of environmental impact upon systemic vascular resistance responsivity and left ventricular mass. It was hypothesized that environmental influences (SES) accounted for a greater proportion of the variance in systemic vascular resistance responsivity and left ventricular mass in African Americans than Caucasian Americans. The hypothesis that systemic vascular resistance responsivity was a pathway through which SES exerted its influence on left ventricular mass was also tested.

The study has been extended through November 2005 to continue examination of the investigator's Twin CV Health cohort (519 pairs of twins who will be 14 to 25 years old). The study provides the unique opportunity to better understand the effects of sodium ion (Na+) retention as a mechanism augmenting systemic vascular resistance responsivity (SVR) and changes in vascular function (i.e., endothelium dependent arterial dilation; EDAD), ventricular structure (i.e., left ventricular mass; LVM) and 24-hour ambulatory BP (ABP). The specific aims are to determine: 1) To what extent is environmental stress related to stress induced Na+ retention, SVR responsivity and preclinical markers of essential hypertension risk and are these relationships stronger in African Americans than Caucasian Americans; 2) Whether stress induced Na+ retention is a pathway linking environmental stress with preclinical markers of essential hypertension risk; and 3) Whether behavioral factors (i.e. John Henryism, anger expression, social support, physical activity) moderate effects of environmental stress on stress induced Na+ retention and/or SVR responsivity and in the preclinical markers of essential hypertension risk, particularly in African Americans.

Study Type

Observational

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

No older than 100 years (Child, Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Male

Description

No eligibility criteria

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Frank Treiber, Augusta University

Publications and helpful links

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General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

September 1, 1996

Primary Completion (Actual)

November 1, 2005

Study Completion (Actual)

November 1, 2005

Study Registration Dates

First Submitted

May 25, 2000

First Submitted That Met QC Criteria

May 25, 2000

First Posted (Estimate)

May 26, 2000

Study Record Updates

Last Update Posted (Estimate)

July 29, 2016

Last Update Submitted That Met QC Criteria

July 28, 2016

Last Verified

May 1, 2009

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 4960
  • R01HL056622 (U.S. NIH Grant/Contract)

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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