ASSESSING CARDIOVASCULAR REACTIVITY IN HUMAN POPULATIONS

Project: Research project

Description

The major purpose of this proposed project shall be to develop a
comprehensive protocol for assessing cardiovascular reactivity to
stressors, for use in epidemiological and clinical investigations of
reactivity and cardiovascular diseases in healthy populations. In
order to devise a valid reactivity protocol we intend to establish
and evaluate procedures for measuring baseline values, providing
appropriate challenge tasks, measuring physiological responses in
appropriate subgroups, and relating cardiovascular measures
obtained in the laboratory to those obtained under more
naturalistic circumstances. Having already explored a large
number of reactivity tasks with major population subgroups, we
intend to proceed with a single large-scale study in order to
examine a sufficient number of subjects to meet the objectives of
the RFA. Thus, the proposed study will enroll 240 subjects into a
2 (male, female) X 2 (black, white) X 2 (25-44 years, 55-64 years)
X 2 (Miami, Durham) design. Subjects will be compared across a
broad range of socioeconomic statuses. Each subject will be
scheduled for 3 laboratory sessions lasting less than 60 min each.
Sessions 1 and 2 will be 2 weeks apart; session 3 will be 6 months
later. During these laboratory sessions subjects will be subjected
to a forehead cold pressor stimulus, a video game and an
evaluative speech stressor. The tasks were chosen because they
are easily administered, capable of eliciting a range of physiologic
responses in healthy people, capable of discriminating population
subgroups, and appear to be reproducible for the same individual
and across different sites. Noninvasive cardiovascular measures
to be assessed will include heart rate; cardiac output; peripheral
resistance; Heather Index; pre-ejection period; left ventricular
ejection period; and systolic, diastolic and mean arterial blood
pressure (BP). On the same day as each laboratory reactivity
session, subjects will wear an ambulatory impedance and
electrocardiogram (ECG) monitor at work and at home. The
following day the subject will wear an ambulatory BP monitor at
work and at home. Data will be analyzed in terms of stability of
baseline values, differences in laboratory reactivity between
groups, differences in reactivity patterns between tasks,
reliability of responses to tasks across sessions, differences in
reactivity as an individual difference variable, and
generalizability of reactivity in the laboratory to cardiovascular
function observed in more naturalistic settings. In order to
accomplish these goals improved procedures will be developed for
monitoring impedance cardiographic and ECG activity both in the
laboratory as well as in more naturalistic settings.
StatusFinished
Effective start/end date7/1/884/30/91

Funding

  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health
  • National Institutes of Health

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Population
Electric Impedance
Electrocardiography
Video Games
Forehead
Individuality
Social Class
Cardiac Output
Cardiovascular Diseases
Heart Rate
hydroquinone

ASJC

  • Medicine(all)