Clinical trial NCT02090842: Milk Proteins, Ambulatory Blood Pressure and Vascular Function
Official title: Investigating the Acute and Chronic Effects of Dietary Proteins on Markers of Vascular Function, Ambulatory Blood Pressure, Insulin Resistance and Lipid Metabolism.
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Hypertension
Keywords: Milk proteins
Blood pressure
Vascular function
Lead sponsor: University of Reading
Sponsor class: OTHER
Collaborators: name: Volac Int. Ltd.
First posted: 2014-03-18
Enrollment: 38
Sex: ALL
Minimum age (years): 30
Maximum age (years): 77
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: PREVENTION

Brief summary: Epidemiological studies demonstrated an inverse associations between cardiovascular events and milk and dairy product consumption. Evidence from human intervention studies suggests that both whey and casein may be effective in blood pressure-lowering, however there is limited data on the impact of milk proteins on vascular function. This research aims to compare the potential acute and chronic impacts of the two main milk proteins (whey and casein) with maltodextrin on blood pressure and vascular function. Furthermore, the effects of these proteins on the markers of insulin resistance, lipid metabolism and inflammatory status will also be investigated in 'at-risk' individuals.

This research includes both an acute and chronic intervention study which have been independently powered on the appropriate outcome measures. This has generated different sample size requirements for the two studies (Actual participants on the acute study: n=27, and on the chronic study: n=38).


Eligibility criteria: Inclusion Criteria:

* A signed consent form
* Blood pressure: 120/80-159/99
* Age: 30-77 years
* BMI 20-40 kg/m2
* Glucose \<7 mmol/l (Not diagnosed with diabetes)
* Chol \<8 mmol/l
* TAG \<4 mmol/l
* Normal liver and kidney function
* Haemoglobin (\>110 g/dl women; 140g/dl men)

Exclusion Criteria:

* Milk allergy, lactose allergy
* Coeliac disease
* Renal, gastrointestinal, respiratory, endocrine, liver disease or cancer
* Surgery in the previous 6 months
* Secondary hypertension
* Excess alcohol consumption (drinking \>28 unit/wk man; \>21 unit/wk women)
* Smoker
* Vegan
* Taking nutritional supplementation (e.g. fish oil, proteins)
* Anaemia

Primary outcomes:
measure: Change in 24-h ambulatory blood pressure
timeFrame: Chronic study: Baseline and week 8 assessments for the three dietary intervention arms, Acute study: automated ambulatory blood monitor measures every 15 minutes for 3 hours after both meals, then every 30 minutes for day
Secondary outcomes:
measure: Changes in vascular reactivity measured by flow-mediated dilation (FMD)
timeFrame: Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: determined at 0 (fasted), 180, 300, 420 min
measure: Changes in plasma lipids
timeFrame: Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: fasted and postprandial
measure: Changes in markers of insulin resistance
timeFrame: Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: fasted and postprandial
measure: Changes in inflammatory markers
timeFrame: Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: fasted and postprandial
measure: Changes in arterial stiffness measured by pulse wave analysis (PWA)
timeFrame: Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: determined at 0 (fasted), 180, 300, 420 min
measure: Changes in arterial stiffness measured by digital volume pulse (DVP)
timeFrame: Chronic study: Baseline and week 8 assessments for the two dietary intervention arms, Acute study: determined at 0 (fasted), 180, 300, 420 min
Other outcomes:
measure: Handgrip strength measurement
timeFrame: Chronic study: Baseline and week 8 assessments for the two dietary intervention arms
measure: Metabonomics
timeFrame: Chronic study: Baseline and week 8 assessments for the two dietary intervention arms; Acute study: fasted and postprandial
Locations:
city: Reading
country: United Kingdom
facility: Department of Food and Nutritional Sciences, University of Reading
state: Berks
Study officials:
affiliation: University of Reading
name: Julie A. Lovegrove, BSc, PhD, RNutr
role: PRINCIPAL_INVESTIGATOR
References:
citation: Pal S, Ellis V. Acute effects of whey protein isolate on blood pressure, vascular function and inflammatory markers in overweight postmenopausal women. Br J Nutr. 2011 May;105(10):1512-9. doi: 10.1017/S0007114510005313. Epub 2011 Jan 28.
citation: Pal S, Ellis V. The chronic effects of whey proteins on blood pressure, vascular function, and inflammatory markers in overweight individuals. Obesity (Silver Spring). 2010 Jul;18(7):1354-9. doi: 10.1038/oby.2009.397. Epub 2009 Nov 5.
citation: Fekete AA, Giromini C, Chatzidiakou Y, Givens DI, Lovegrove JA. Whey protein lowers blood pressure and improves endothelial function and lipid biomarkers in adults with prehypertension and mild hypertension: results from the chronic Whey2Go randomized controlled trial. Am J Clin Nutr. 2016 Dec;104(6):1534-1544. doi: 10.3945/ajcn.116.137919. Epub 2016 Oct 26.