Sympathetic Regulation of Large Artery Stiffness in Humans With ISH

Early Phase 1

Recruiting

• Conditions: Stiffness, Aortic; Hypertension, Systolic
• Interventions: Drug: Clonidine; Drug: Placebo; Drug: Hydrochlorothiazide

• Registration Number: NCT04423627
• Lead Sponsor: University of Iowa

Brief Summary

Stiffening of your blood vessels, particularly the large vessels from your heart (called the aorta and carotids) you age contributes to the development of cardiovascular disease (CVD) such as heart attack and stroke. Nerve activity from your brain to your body also increases with advancing age but it is unknown if this nerve activity contributes directly to the stiffening on your blood vessels in older adults in addition to high blood pressure. Therefore, successful completion of the proposed aims will have a significant clinical impact by identifying if nerve activity from your brain could be a novel target for therapies that would lower stiffness of the aorta and carotid arteries in older adults.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2020-06-05
• Study First Submitted QC: 2020-06-08
• Study First Posted: 2020-06-09
• Study Start: 2021-06-01
• Status Verified: 2024-04
• Last Update Submitted: 2024-04-17
• Last Update Posted: 2024-04-19
• Primary Completion: 2025-06-30
• Study Completion: 2025-12-30

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 78

Inclusion Criteria

• age 60-85
• non-smoking
• clinically healthy
• untreated or treated stage 1 isolated systolic hypertension (ISH) (systolic BP 130-139 mmHg; diastolic BP <90 mmHg) or stage 2 ISH (systolic BP 140-159 mmHg; diastolic BP <90 mmHg) per 2017 AHA/ACC hypertension guidelines
• if subject is on antihypertensive medications, they will stop taking medication for a one-week washout period after Visit 1 before they return for Visit 2. They will come in at day 3 and day 7 of the one-week washout for a BP reading, to confirm that systolic BP is <160 mmHg.

Exclusion Criteria

• no history of cardiovascular disease (e.g., myocardial infarction, bypass surgery, angioplasty/stent, heart failure, cardiomyopathy, pacemaker/defibrillator, peripheral artery disease), pulmonary disease, liver disease, Type I or II diabetes, cancer (treated by chemotherapy and/or radiation), psychiatric illness, on aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs).
• aspirin, NSAIDs, vitamins, herbal supplements, omega-3-fatty acids will have to discontinue for at least 1 week before participation and remain discontinued during the study.
• blood thinners, serotonin reuptake inhibitors (SSRIs), or PDE5 inhibitors will also be excluded.
• Women must be postmenopausal for at least 6 months (surgical or natural) and not currently on hormone replacement therapy.
• Subjects not on antihypertensive will not be eligible if their resting clinic systolic BP is <130 mmHg or >160 mmHg and diastolic BP >90 mmHg.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Clonidine	Clonidine	0.2 mg/day oral
Placebo	Placebo	Placebo
Hydrochlorothiazide	Hydrochlorothiazide	37.5 mg/day oral

Primary Outcome Measures

Name	Time	Method
Change in carotid-femoral pulse wave velocity	Baseline and after 4 weeks	Aortic stiffness

Secondary Outcome Measures

Name	Time	Method
Change in carotid flow pulsatility index	Baseline and after 4 weeks	Change in carotid flow pulsatility
Change in carotid distensibility index	Baseline and after 4 weeks	Change in carotid distensibility
Change in carotid intimal medial thickness (IMT)	Baseline and after 4 weeks	Change in carotid wall thickness

Trial Locations

Locations (2)

Amy Stroud; 🇺🇸 Iowa City, Iowa, United States

University of Iowa; 🇺🇸 Iowa City, Iowa, United States