Clinical Trial Details
— Status: Withdrawn
Administrative data
NCT number |
NCT04346511 |
Other study ID # |
11943 |
Secondary ID |
|
Status |
Withdrawn |
Phase |
Phase 2
|
First received |
|
Last updated |
|
Start date |
May 9, 2020 |
Est. completion date |
December 5, 2022 |
Study information
Verified date |
November 2023 |
Source |
University of Oklahoma |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Cerebrovascular diseases (CVD) and neurodegenerative diseases (NDD) are both leading causes
of death in the United States. Epidemiological data have shown that increased prevalence of
hypertension is related to these outcomes. However, despite the strong association of poor
brain health outcomes in patients with hypertension (HTN), the understanding of cerebral
blood flow (CBF) regulation and treatment options for HTN remain limited. Acupuncture
treatment (AT), which is considered a promising complementary and integrative modality, has
been known to reduce blood pressure and improve endothelial function in HTN. However, very
few studies have investigated AT's effect on cerebrovascular function and the possible
neuroprotective properties directly via regulating HTN. Exercise is used as a stimulus that
increases the brain's metabolism and requires cerebrovascular responses (vasodilation) to
meet the new metabolism.
Therefore, the specific aim of this study is to test the hypothesis that an antihypertensive
acupuncture treatment can acutely improve cerebrovascular responses in hypertensive humans
during moderate exercise.
Description:
After IRB approval, experiments will take place in the Human Circulation Research Laboratory
in the Department of Health and Exercise on the OU Norman campus. All subjects will complete
a total of 3 visits. The first is a screening visit to provide informed consent and to ensure
the potential participant meets all inclusion criteria and no exclusion criteria. Once
enrolled, participants will complete two experimental trials (Placebo (PL, Sham Acupuncture)
or Real Acupuncture (RA), randomized) in a single-blinded crossover design. PL or RA
treatment will precede testing by ~25min before to maximize acute responses. Test begins with
5 min of quiet rest where baseline measurements are taken, followed by 5 min of exercise.
After exercise, subjects will be given 5 min of quiet rest.
Visit 1 (Screening day): ~1.5 hours. The screening visit will include informed consent,
health history, physical activity questionnaires and blood sample. If qualified, the subject
will be enrolled in the study and they will complete a maximal oxygen uptake (VO2max) cycle
ergometer test to determine fitness.
Visit 2 & 3 (Study day): ~1.5 hours. Instrumentation: Subjects will be equipped with ECG for
heart rate (HR), photoplethysmography for blood pressure, pulse oximeter, mouthpiece for
end-tidal CO2 (PETCO2) and oxygen uptake (VO2), near-infrared spectroscopy (NIRS) for active
muscle oxygenation and Transcranial Doppler (TCD) for CBF. Real Acupuncture (RA): Subjects
will receive ~20 minutes of RA treatment prior to exercise. Placebo (PL): Specially designed
Sham Acupuncture needles will be used in the same acupoints, for the same duration as RA.
All subjects will complete a total of 3 visits separated by a minimum of 48 hours. Each study
visit will take ~1.5 hours. The investigators anticipate ~ 6 hours or less of total
involvement of the participants' time.
This study is a single-blind crossover design. Participants will be blinded in two trials.
Practitioners and operators will not be allowed to communicate with the participants
concerning the type of acupuncture devices. Outcome assessors and statisticians may not be
blinded to treatment allocation.
The key dependent variable of interest is change (delta) in cerebrovascular conductance index
(CVCi = CBF/blood pressure) from rest to exercise (delta CVCi = CVCiExercise - CVCiRest).
Delta CVCi is the most common assessment of vasodilation in humans as it normalizes
differences in blood flow to differences in blood pressure. CVCi calculates how much blood
flow is observed for a given pressure. A change in CVCi (delta CVCi) has a predictable
relationship where + delta CVCi indicates vasodilation (more flow for a given pressure) and -
delta CVCi indicates vasoconstriction (less flow for a given pressure). Data will be analyzed
using a general linear model approach (similar to ANOVA). Based on pilot data, a total sample
size of 40 (20 CON and 20 HTN) will provide a power of 0.9. A minimum of 60 participants will
be to recruited to ensure statistical power is achieved.