Clinical trial NCT01331486: Nitric Oxide Mediated Vasodilatory Response to Hawthorn Standardized Extract
Official title: Nitric Oxide Mediated Vasodilatory Response to Hawthorn Standardized Extract
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE1
Conditions: Prehypertension
Mild Hypertension
Keywords: Prehypertension
Mild hypertension
Flow mediated dilation
Hawthorn
Lead sponsor: University of North Carolina, Chapel Hill
Sponsor class: OTHER
First posted: 2011-04-08
Enrollment: 24
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER

Brief summary: 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.


Eligibility criteria: 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).

Primary outcomes:
measure: FMD Max
timeFrame: 7d
Secondary outcomes:
measure: BP
timeFrame: 7d
Other outcomes:
Locations:
city: Chapel Hill
country: United States
facility: UNC Department of Family Medicine
state: North Carolina
Study officials:
affiliation: UNC
name: Gary N Asher, MD, MPH
role: PRINCIPAL_INVESTIGATOR
References:
citation: Asher GN, Viera AJ, Weaver MA, Dominik R, Caughey M, Hinderliter AL. Effect of hawthorn standardized extract on flow mediated dilation in prehypertensive and mildly hypertensive adults: a randomized, controlled cross-over trial. BMC Complement Altern Med. 2012 Mar 29;12:26. doi: 10.1186/1472-6882-12-26.