Effects of Almonds on Vascular Reactivity in Patients With Coronary Artery Disease

Effects of Almonds on Vascular Reactivity and Biomarkers of Inflammation, Oxidative Stress and Endothelial Function in Patients With Coronary Artery Disease

This is a study of the effects of 3 oz almonds added daily to a National Cholesterol Education Program Therapeutic Lifestyle Changes (TLC) diet in improving endothelial function in patients with Coronary Artery Disease. The study seeks to determine if these effects are mediated via an increase in Nitric Oxide synthesis and reductions in dyslipidemia and systemic inflammation.

Vascular reactivity will be assessed via flow mediated dilation with endothelium-independent and hyperemic flow measured in the right brachial artery by non-invasive 2-dimensional and Doppler ultrasound. Serum will be collected and analyzed for biomarkers of dyslipidemia, inflammation, endothelial function, vascular reactivity and oxidative stress.

Study Overview

• Status: Completed
• Conditions: Cardiovascular Diseases; Hypertension; Heart Disease; Endothelial Dysfunction; Vascular Disease
• Intervention / Treatment: Dietary supplement: Almonds; Dietary supplement: Placebo Comparator:

Detailed Description

The study is a randomized, crossover, 6 week intervention trial design with a 6 week run in on the TLC diet and a 6 week washout on the TLC diet between control and intervention periods. Forty subjects with verified and stable coronary artery disease will be enrolled in the study. The control intervention involved maintaining a steady TLC diet without nuts which will be monitored with counseling and dietary assessments. The almond intervention involved consuming 3 oz. of almonds per day and adjusting lipid intake to remain isocaloric with the TLC diet alone. Again subjects will be monitored with counseling and dietary assessments.

At the beginning and end of each intervention period subjects will be tested for endothelial function using flow mediated dilation and blood and urine samples will be collected for biochemical analysis for markers of inflammation, dyslipidemia, and oxidative stress.

• Study Type: Interventional
• Enrollment (Actual): 45
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02111
      • Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University (HNRCA)

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Stable CAD Patients (men & postmenopausal women)
• aged 20-80 years
• weighing less than 115 Kg (BMI range 18.5-35 kg/m2)
• with coronary artery disease defined by the presence of lesions on coronary angiography, history of myocardial infarction, or positive stress test.
• Subjects are eligible to participate after a stent procedure only after they have been stable for one month after the stent procedure.
• All Ethnic Groups.
• Languages: English

Exclusion Criteria:

• Subjects with heart failure are not eligible for participation in this study.
• History or known allergy to nuts of any kind
• Women with a positive urine beta HCG pregnancy test and lactating women or women who are planning to become pregnant.
• Regular consumption of ≥ 5 oz nuts/week for 6 weeks prior to study admission
• Clinical history of other major illness including end-stage cancer, renal failure, hepatic failure, gastrointestinal disorders that may impair absorption, or other conditions that in the opinion of the principal investigator make a clinical study inappropriate.
• Regular use of oral steroids
• Cigarette smoking and/or nicotine replacement use
• Regular daily intake of ≥ 2 alcoholic drinks
• Illicit drug use
• History of a psychological illness or condition such as to interfere with the subject's ability to understand the requirements of the study.
• No dietary supplements containing phenolic compounds, i.e., herbal preparations, or berry containing preparations (such as cranberry capsules) for one month prior to study admission.
• Treatment with an investigational new drug within the last 30 days.
• Treatment with Vitamin E, Vitamin C, beta carotene, lipoic acid, or other food or herbal supplements within 1 month of enrollment (subjects taking multivitamins or other forms of vitamin E and C in doses that do not exceed two times the RDA will not be excluded).
• The following medications will be withheld in the morning of each ultrasound study visit as follows:

All vasoactive medications (nitrates, calcium channel blockers, beta blockers, angiotensin converting enzyme inhibitors, and other vasodilators). Subjects will take their medications immediately after the ultrasound measurements are taken.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: almonds; 3 oz/d almonds	Dietary supplement: Almonds; 3 oz. of almonds per day, supplied as 1 oz. snack packs to be consumed for 6 weeks.; Other Names: Nuts
Placebo Comparator: Placebo; NCEP Step 2 diet	Dietary supplement: Placebo Comparator: NCEP Step 2 diet

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Endothelial Function as determined by flow mediated dilation and and biochemical markers of endothelial function.	After 6 weeks eating almonds

Secondary Outcome Measures

Outcome Measure	Time Frame
Biochemical markers of inflammation, such as cytokines	After 6 weeks of eating almonds
Biochemical markers of dyslipidemia, such as lipid profiles	After 6 weeks of eating almonds
Biomarkers of oxidative stress, such as isoprostanes and 8OHdG	After 6 weeks of eating almonds

Collaborators and Investigators

• Sponsor: Tufts University
• Collaborators: Boston University
• Investigators: Principal Investigator: Jeffrey B Blumberg, PhD, HNRCA Tufts University; Principal Investigator: Joseph Vita, MD, Boston University

Publications and helpful links

General Publications

• Chen CY, Holbrook M, Duess MA, Dohadwala MM, Hamburg NM, Asztalos BF, Milbury PE, Blumberg JB, Vita JA. Effect of almond consumption on vascular function in patients with coronary artery disease: a randomized, controlled, cross-over trial. Nutr J. 2015 Jun 17;14:61. doi: 10.1186/s12937-015-0049-5.

Study record dates

Study Major Dates

• Study Start: October 1, 2008
• Primary Completion (Actual): January 1, 2011
• Study Completion (Actual): January 1, 2011

Study Registration Dates

• First Submitted: October 28, 2008
• First Submitted That Met QC Criteria: October 28, 2008
• First Posted (Estimate): October 29, 2008

Study Record Updates

• Last Update Posted (Actual): April 28, 2017
• Last Update Submitted That Met QC Criteria: April 26, 2017
• Last Verified: April 1, 2017

More Information

Terms related to this study

• Keywords: inflammation; oxidative stress; heart disease; dyslipidemia; almonds; vascular reactivity
• Additional Relevant MeSH Terms: Arteriosclerosis; Arterial Occlusive Diseases; Heart Diseases; Coronary Artery Disease; Myocardial Ischemia; Coronary Disease; Cardiovascular Diseases; Vascular Diseases
• Other Study ID Numbers: TuftsIRB8723