Wild Blueberries and Cardiovascular Health in Middle-aged/Older Men and Postmenopausal Women

NCT04530916 | Active Not Recruiting Phase 1

• 1 other identifier: 1775
• Study Type: interventional
• Target: 58
• Locations: 1 country
• Sites: 1

Brief Summary

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality worldwide. Aging is the primary risk factor for CVD, in large part due to adverse modifications to the arteries. These modifications include vascular endothelial dysfunction and arterial stiffness. Vascular endothelial dysfunction is an initiating step in atherosclerosis, and is primarily caused by reduced nitric oxide (NO) bioavailability secondary to excessive superoxide-driven oxidative stress and inflammation. Endothelial dysfunction leads to arterial stiffness and the development of hypertension (HTN) which further increases CVD. Greater than 2/3 of the US population has elevated blood pressure or stage 1-HTN. As such, interventions that improve vascular endothelial dysfunction by increasing NO bioavailability and mitigating excessive oxidative stress and inflammation are needed. Blueberries are rich in bioactive compounds including flavonoids, phenolic acids, and pterostilbene. These compounds and their metabolites have been shown to attenuate oxidative stress and inflammation. The primary goal of this study is to assess the efficacy of blueberries to improve reduce blood pressure and improve vascular endothelial dysfunction and arterial stiffness in middle-aged/older men with elevated blood pressure or stage 1-HTN.

Conditions

Hypertension; Aging; Endothelial Dysfunction; Men

Keywords

Cardiovascular Disease; Blueberries; Hypertension; Vascular Dysfunction; Atherosclerosis; Aging

Outcome Measures

Primary Outcomes (1)

• Reactive hyperemia index

  Endothelial function assessed as reactive hyperemia index using peripheral arterial tonometry (EndoPat)

  Baseline to 12 Weeks

Secondary Outcomes (11)

• Augmentation index

  Baseline to 12 Weeks

• Pulse wave velocity

  Baseline to 12 Weeks

• Endothelial cell protein expression

  Baseline to 12 Weeks

• Hemoglobin A1c

  Baseline to 12 Weeks

• Lipid profile

  Baseline to 12 Weeks

Study Arms (2)

Blueberry

EXPERIMENTAL

22 g blueberry powder per day

Dietary Supplement: Blueberry Powder

Control

PLACEBO COMPARATOR

22 g placebo control powder per day

Dietary Supplement: Placebo Powder

Interventions

Blueberry Powder DIETARY_SUPPLEMENT

22 g/day wild blueberry powder

Blueberry

Placebo Powder DIETARY_SUPPLEMENT

22 g/day placebo powder

Control

Eligibility Criteria

• Age: 45 Years - 70 Years
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Men and postmenopausal women
• Aged 45-70 years
• Elevated blood pressure or stage 1-Hypertension
• Ability to provide informed consent

You may not qualify if:

• Have had a menstrual cycle within the past year
• Blood Pressure \< 120 (systolic BP) or ≥ 140/90 mm Hg
• Reactive hyperemia index \> 3.00%
• Taking \> 1 antihypertensive medication, taking 1 antihypertensive medication more than 1 time per day, and/or taking the antihypertensive medication for \< 3 months
• Diagnosed cancer, cardiovascular disease, diabetes, or gastrointestinal, kidney, liver, lung, and/or pancreatic disease
• Triglycerides \> 350 mg/dL, low-density lipoprotein cholesterol (LDL-C) ≥ 190 mg/dL, hemoglobin A1c ≥ 6.5%, and/or taking a lipid-lowering or glucose-lowering medication
• Testosterone or estrogen replacement therapy use 6 months prior to study start
• Weight change ≥ 3 kg in the past 3 months, actively trying to lose weight, or unwilling to remain weight stable throughout the study
• Current smokers or history of smoking in the past 12 months
• Binge and/or heavy drinker (\>3 drinks on any given occasion and/or \>7 drinks/week for women, and \>4 drinks on any given occasion and/or \>14 drinks/week for men)
• Body mass index \< 18.5 or \> 40 kg/m2
• Antibiotic therapy within past two months
• Allergies or contraindication to study treatments or procedures

Sponsors & Collaborators

• Colorado State University: lead
• Wild Blueberry Association of North America: collaborator

Study Sites (1)

Food and Nutrition Clinical Research Laboratory

Fort Collins, Colorado, 80523-1571, United States

Location

Related Publications (1)

• Johnson SA, Figueroa A, Navaei N, Wong A, Kalfon R, Ormsbee LT, Feresin RG, Elam ML, Hooshmand S, Payton ME, Arjmandi BH. Daily blueberry consumption improves blood pressure and arterial stiffness in postmenopausal women with pre- and stage 1-hypertension: a randomized, double-blind, placebo-controlled clinical trial. J Acad Nutr Diet. 2015 Mar;115(3):369-377. doi: 10.1016/j.jand.2014.11.001. Epub 2015 Jan 8.

  PMID: 25578927 BACKGROUND

MeSH Terms

Conditions

Hypertension; Multiple Endocrine Neoplasia Type 1; Cardiovascular Diseases; Atherosclerosis

Condition Hierarchy (Ancestors)

Vascular Diseases; Multiple Endocrine Neoplasia; Endocrine Gland Neoplasms; Neoplasms by Site; Neoplasms; Neoplasms, Multiple Primary; Neoplastic Syndromes, Hereditary; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Endocrine System Diseases; Arteriosclerosis; Arterial Occlusive Diseases

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: January 27, 2020
• First Posted: August 28, 2020
• Study Start: January 1, 2020
• Primary Completion: March 31, 2025
• Study Completion: December 31, 2025
• Last Updated: November 17, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)