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OpenTrials
Completed

NCT Number: NCT04423627

Sympathetic Regulation of Large Artery Stiffness in Humans With ISH

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.

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Key information

Age range

60 year–85 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Early Phase 1

Primary location

Amy Stroud, Iowa City, Iowa, United States

Loading trial locations.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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.

Treatment and study plan

Clonidine

Drug

Clonidine 0.2 mg/day oral tablet

Hydrochlorothiazide

Drug

Hydrochlorothiazide 37.5 mg/day oral tablet

Placebo

Drug

Placebo

Primary outcomes

  1. Change in carotid-femoral pulse wave velocity

    Time frame: Baseline and after 4 weeks

    Aortic stiffness

Secondary outcomes

  1. Change in carotid distensibility index

    Time frame: Baseline and after 4 weeks

    Change in carotid distensibility

  2. Change in carotid flow pulsatility index

    Time frame: Baseline and after 4 weeks

    Change in carotid flow pulsatility

  3. Change in carotid intimal medial thickness (IMT)

    Time frame: Baseline and after 4 weeks

    Change in carotid wall thickness

Sponsors and collaborators

Lead sponsor

University of Iowa

Other

Registry information

Official study title

Sympathetic Regulation of Large Artery Stiffness in Humans With Age-Related Isolated Systolic Hypertension

Acronym: SELECT

Important dates

Study start
2021
Primary completion
2025
Study completion
2025
First posted
Jun 9, 2020
Registry last updated
Aug 8, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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