Nitric Oxide Mediated Vasodilatory Response to Hawthorn Standardized Extract

University of North Carolina (UNC)

Status and phase: Completed; Phase 1

Conditions: Prehypertension; Mild Hypertension

Treatments: Dietary Supplement: Placebo capsule; Dietary Supplement: Hawthorn

Study type: Interventional

Funder types: Other

Identifiers

NCT01331486

09-2279

Details and patient eligibility

About

Prehypertension and mild hypertension affect an estimated 157 million U.S. adults. Cardiovascular disease (CVD) risk and associated mortality is elevated in this population. Treatment options are limited consisting of lifestyle modification, which is often ineffective, or drug therapy, which carries risk of side effects. Highly safe, efficacious, and acceptable treatment options for this population are needed. Hawthorn standardized extract (HSE) is approved for use in Europe to treat heart failure, and preliminary evidence suggests it may have a blood pressure lowering effect. However, prior trials of hawthorn have based dosage recommendations on animal studies. Therefore, the investigators propose a dose-finding study to measure the pharmacodynamic effect of three doses of standardized hawthorn extract and placebo.

Enrollment: 24 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Recent ambulatory daytime systolic BP average between 120 - 155 mmHg or diastolic BP between 80-95 mmHg
2. Age 18 years and older.
3. Ability to speak English

Exclusion criteria

1. Any antihypertensive medication use (ACE inhibitors, ARB, beta-blockers, calcium channel blockers, diuretics, alpha agonists or antagonists, nitrates, direct vasodilators such as hydralazine, aldosterone antagonists, direct renin inhibitors, endothelin antagonists)
2. Current tobacco use.
3. Diagnosed with diabetes, known coronary artery disease, severe aortic stenosis, idiopathic hypertrophic subaortic stenosis (IHSS), or upper extremity vascular obstruction.
4. Pregnancy or breast feeding.
5. Using estrogen-containing birth control methods.
6. Unwillingness to forgo vitamins C and E, fish oil, niacin, arginine, OTC decongestants, and NSAIDs such as advil, motrin, and nuprin during the study period.
7. Unwillingness to forgo use of phosphodiesterase inhibitors (sildenafil - 36 hours, vardenafil - 36 hours, tadalafil - 96 hours) prior to study visits.
8. Unwillingness to refrain from vigorous exercise on the morning of study visits.
9. Women with childbearing potential who do not agree to practice effective birth control (condom, diaphragm, cervical cap, copper IUD, abstinence).

Trial design

24 participants in 4 patient groups, including a placebo group

Placebo

Placebo Comparator group

Description:

Placebo capsule

Treatment:

Dietary Supplement: Placebo capsule

Low dose

Active Comparator group

Treatment:

Dietary Supplement: Hawthorn

Mid dose

Active Comparator group

Treatment:

Dietary Supplement: Hawthorn

High dose

Active Comparator group

Treatment:

Dietary Supplement: Hawthorn