Arterial Stiffness, Healthy Participants, Microangiopathy, Diabetic, Optical Tomography, Polyphenol, Vascular Endothelium
Conditions
Brief summary
The greatest challenge in our ageing society are cardiovascular diseases such as stroke, heart attack, peripheral artery disease of the legs with non-healing wounds (ulcers), or diabetes. Specific diets with high polyphenol content are associated with lower incidence of cardiovascular disease and can improve macrovascular function when consumed acutely and chronically. Which role the smallest blood vessels (microcirculation) play in this and if the microcirculation responds to therapies is not well understood. One reason for this is that no generally available medical instrument has the resolution to study the microcirculation. The recently developed optical coherence tomography angiography (OCTA), currently mainly used by eye doctors, is able to visualise the microcirculation. The current randomised controlled cross-over proof-of-concept study will test the acute effect of a cocoa flavanol intervention on cutaneous microvascular structure and function of hands and feet together with macrovascular function of upper and lower extremities in healthy and type 2 diabetes participants. It is the hypothesis that cocoa flavanol intervention as compared to placebo can acutely increase microvascular vasodilation and macrovascular endothelial function in arms and legs together with arterial stiffness in both healthy and type 2 diabetes participants.
Interventions
DIETARY_SUPPLEMENTCocoa flavanol
Commercially available Cocoa Via Brand capsules containing 1350 mg cocoa flavanols (6 capsules)
OTHERPlacebo
Capsules identical to ccocoa flavanol capsules filled with calorically matched brown sugar (6 capsules)
Sponsors
University of Surrey
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Masking description
Placebo and cocoa flavanols will be delivered in same number of identical appearing capsules
Intervention model description
2 group (healthy and type 2 diabetes) randomised controlled cross-over (2-period, 2-sequence) study
Eligibility
Sex/Gender
ALL
Age
20 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
Healthy: Inclusion Criteria: * Healthy, 20-70 years * BMI 20-30 kg/m\^2
Exclusion criteria
* Diabetes mellitus * Symptoms of acute infection * Cardiac rhythm other than sinus * Active malignancy * Clinical signs or symptoms of cardiovascular disease (coronary artery disease, lower extremity artery disease, cerebrovascular disease): angina pectoris, dyspnea, palpitation, syncope, claudication * Active vasoactive medication. Type 2 Diabetes: Inclusion Criteria: * Type 2 diabetes mellitus * 20-70 years * BMI 20-30 kg/m\^2
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Microvascular dilation | Change at 2 hours as compared to baseline after ingestion of cocoa flavanol vs placebo | Microvascular diameter increase in response to 5 min limb occlusion on hands and feet |
| Macrovascular endothelial function | Change at 2 hours as compared to baseline after ingestion of cocoa flavanol vs placebo | Flow-mediated dilation determined with ultrasound in brachial and common femoral artery |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Leg perfusion pressure | Change at 2 hours as compared to baseline after ingestion of cocoa flavanol vs placebo | Doppler based perfusion pressure of leg |
| Blood pressure | Change at 2 hours as compared to baseline after ingestion of cocoa flavanol vs placebo | Upper arm blood pressure measured with Arteriograph |
| Arterial stiffness | Change at 2 hours as compared to baseline after ingestion of cocoa flavanol vs placebo | Pulse wave velocity (Arteriograph) |
Other
| Measure | Time frame | Description |
|---|---|---|
| Photoplethysmography (PPG) based pulse wave velocity (PWV) | Change at 2 hours as compared to baseline after ingestion of cocoa flavanol vs placebo | PWV velocity calculated based on PPG sensor at hand and foot |
| Photoplethysmography (PPG) blood flow | Change at 2 hours as compared to baseline after ingestion of cocoa flavanol vs placebo | Based on PPG signals on hand and foot |
Countries
United Kingdom
Outcome results
None listed