Anxiety-mediated Impairments in Large Elastic Artery Function and the Autonomic Nervous System
Status:
Active, not recruiting
Trial end date:
2023-12-31
Target enrollment:
Participant gender:
Summary
The goal of this study is to evaluate the effectiveness of a short-term (4 weeks)
pharmacological blockade of sympathetic nerve activity (clonidine) on anxiety symptoms,
vascular function, inflammation, muscle sympathetic nerve activity, and oxidant stress in
individuals with moderate-to-high anxiety. Individuals who are interested in the study will
be identified by an online screening survey and will be contacted by the research team;
advertisements, flyers and mass emails will direct individuals to the online screening
survey. Those deemed eligible to participate will be randomized to either the clonidine
intervention or hydrochlorothiazide as a blood-pressure lowering control condition. If
eligible participants are currently being treated with blood pressure-lowering medications,
they will be asked to go off these medications for 2 weeks prior to and during the course of
the study. During the 2 week washout of blood pressure-lowering medications, participants
will have safety visits (2 additional visits) that include measurements of blood pressure at
4 days and 7 days after the beginning of the washout period before the intervention.
Assessments of anxiety symptoms via various surveys, vascular function (via non-invasive,
well-established techniques), inflammation, muscle sympathetic nerve activity, and oxidant
stress will be performed at baseline and at the post intervention session. Similar baseline
measurements will be performed in control subjects with low or no anxiety for comparison, but
these individuals will not undergo the intervention.
Participants with moderate-to-high anxiety will have a total of 6 visits to the laboratory,
which includes the screening and consent (visit 1). Visit 2 (baseline measurements) and visit
6 (post-intervention measurements) will be more extensive (~4.5 hours) compared to the other
visits (~30 min). Participants completing the washout will have an additional 2 visits (~30
min each) before "visit 2." Control subjects with low or no anxiety will only participate in
visit 1 (screening and consent ) and visit 2 (baseline measurements).