Blueberries for Improving Vascular Endothelial Function in Postmenopausal Women With Elevated Blood Pressure
| Status: | Recruiting |
|---|---|
| Conditions: | High Blood Pressure (Hypertension), Cardiology, Women's Studies |
| Therapuetic Areas: | Cardiology / Vascular Diseases, Reproductive |
| Healthy: | No |
| Age Range: | 45 - 65 |
| Updated: | 2/14/2019 |
| Start Date: | December 2, 2017 |
| End Date: | December 31, 2019 |
| Contact: | Nicole S. Litwin, MS, RD |
| Email: | Nicole.Litwin@colostate.edu |
| Phone: | (970) 491-0464 |
Blueberry Consumption for Improving Vascular Endothelial Dysfunction in Postmenopausal Women With Elevated Blood Pressure and Stage 1-Hypertension
Postmenopausal women are at an increased risk of developing cardiovascular disease (CVD)
largely due to accelerated aging-related modifications to vascular health following
menopause. The vascular endothelium is responsible for producing chemicals that are essential
for proper vasodilation and blood flow and therefore is involved in maintaining normal blood
pressure. A major modification that occurs during aging and is accelerated during menopause
is termed vascular endothelial dysfunction which is characterized by impaired
endothelium-dependent dilation. This can lead to increased blood pressure, atherosclerosis,
and increased risk of CVD and death. Nitric oxide (NO) is a chemical produced by the
endothelium and is essential for normal endothelial function and cardiovascular health.
Vascular endothelial dysfunction is primarily caused by reduced NO bioavailability secondary
to excessive oxidative stress. Approximately 3/4 of postmenopausal women have elevated blood
pressure or hypertension which further worsens endothelial function and increases CVD risk
through increased oxidative stress and inflammation. Blueberries are rich in phytochemicals
including anthocyanins, phenolic acids, and pterostilbene. These phytochemicals and their
metabolites are known to attenuate oxidative stress and inflammation. The overall goal of the
current study is to assess the efficacy of blueberries to improve vascular endothelial
dysfunction in this high-risk population and to gain insight into underlying mechanisms. 58
postmenopausal women with elevated blood pressure and stage 1-HTN and vascular endothelial
dysfunction at the screening visit will be asked to consume 22 grams freeze-dried blueberry
powder or placebo powder per day for 12 weeks. Vascular endothelial function will be assessed
at baseline and 12 weeks. Measurements indicative of vascular nitric oxide production,
oxidative stress, inflammation, cardiometabolic health, cognitive function, and blueberry
phytochemical metabolism will be measured at baseline and 12 weeks. Blood pressure will be
assessed at baseline and 4, 8, and 12 weeks.
largely due to accelerated aging-related modifications to vascular health following
menopause. The vascular endothelium is responsible for producing chemicals that are essential
for proper vasodilation and blood flow and therefore is involved in maintaining normal blood
pressure. A major modification that occurs during aging and is accelerated during menopause
is termed vascular endothelial dysfunction which is characterized by impaired
endothelium-dependent dilation. This can lead to increased blood pressure, atherosclerosis,
and increased risk of CVD and death. Nitric oxide (NO) is a chemical produced by the
endothelium and is essential for normal endothelial function and cardiovascular health.
Vascular endothelial dysfunction is primarily caused by reduced NO bioavailability secondary
to excessive oxidative stress. Approximately 3/4 of postmenopausal women have elevated blood
pressure or hypertension which further worsens endothelial function and increases CVD risk
through increased oxidative stress and inflammation. Blueberries are rich in phytochemicals
including anthocyanins, phenolic acids, and pterostilbene. These phytochemicals and their
metabolites are known to attenuate oxidative stress and inflammation. The overall goal of the
current study is to assess the efficacy of blueberries to improve vascular endothelial
dysfunction in this high-risk population and to gain insight into underlying mechanisms. 58
postmenopausal women with elevated blood pressure and stage 1-HTN and vascular endothelial
dysfunction at the screening visit will be asked to consume 22 grams freeze-dried blueberry
powder or placebo powder per day for 12 weeks. Vascular endothelial function will be assessed
at baseline and 12 weeks. Measurements indicative of vascular nitric oxide production,
oxidative stress, inflammation, cardiometabolic health, cognitive function, and blueberry
phytochemical metabolism will be measured at baseline and 12 weeks. Blood pressure will be
assessed at baseline and 4, 8, and 12 weeks.
Inclusion Criteria:
- Aged 45-65 years
- Postmenopausal women (≥ 1 years postmenopausal; natural or surgical menopause;
confirmed by measurement of estradiol at a level < 30 pg/mL and follicle-stimulating
hormone at a level ≥ 30 mIU/mL)
- Elevated or stage 1-HTN (confirmed as resting seated systolic blood pressure < 120 or
≥ 139 mmHg and/or a diastolic blood pressure ≥ 90 mmHg using an average of 3
measurements, on 2 separate occasions - screening and baseline visits)
- Baseline vascular endothelial dysfunction defined as brachial artery flow-mediated
vasodilation < 7%
- Ability to provide informed consent
Exclusion Criteria:
- Systolic blood pressure < 120 or ≥ 139 mm Hg and/or diastolic blood pressure ≥ 90 mmHg
- Taking > 1 antihypertensive medication and/or taking the antihypertensive medication
for < 3 months
- Diagnosed cancer, cardiovascular disease, diabetes, or gastrointestinal, kidney,
liver, and/or pancreatic disease
- Triglycerides > 350 mg/dL, low-density lipoprotein cholesterol (LDL-C) ≥ 190 mg/dL,
and/or taking a lipid-lowering medication
- Hormone replacement therapy use 6 months prior to study start
- Taking phosphodiesterase-5 inhibitors
- 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
- Active infection or antibiotic therapy
- Allergies or contraindication to study treatments, pharmacological agents, or
procedures
We found this trial at
1
site
11220 US Highway 30
Fort Collins, Colorado 80523
Fort Collins, Colorado 80523
Phone: 970-491-0464
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