Clinical trial NCT01478958: Dietary Intervention and Vascular Function
Official title: The Effects of the Substitution of Dietary SFA With n-6 PUFA or MUFA on Vascular Function
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Cardiovascular Disease
Keywords: fatty acids
cardiovascular disease
vascular function
microparticles
Lead sponsor: University of Reading
Sponsor class: OTHER
First posted: 2011-11-23
Enrollment: 202
Sex: ALL
Minimum age (years): 21
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

Brief summary: It is well established that diet plays an important role in both the development and progression of heart disease. Different types of dietary fat have varying effects on heart disease risk factors. The elasticity of an individual's blood vessels is strongly associated with heart disease risk and recent evidence suggests that dietary manipulation may influence elasticity of the blood vessels with dietary fat (including saturated, monounsaturated and polyunsaturated fatty acids) as a potentially important modulator. Substantial evidence exists on the effects of monounsaturated fats (type of fatty acids mainly found in olive and rapeseed oil), n-6 polyunsaturated fats (type of polyunsaturated fatty acids found in vegetable oils) and saturated fat (found mainly in animal derived products) on lipid levels. However, the influence of these dietary fats on the elasticity of blood vessels remains unclear.The main purpose of the DIVAS study is to determine the effects of the substitution of saturated fats with either n-6 polyunsaturated or monounsaturated fats on blood vessel elasticity and to determine the effects of these different dietary fats on other risk factors for heart disease including lipoproteins and inflammatory biomarkers.


Eligibility criteria: Inclusion Criteria:

Adults should have a relative risk (RR) of \> 1.5 of developing cardiovascular disease (CVD) based on presenting with at least one recognised risk factor for CVD:

* total cholesterol (TC) \> 6.0 mmol/l
* HDL cholesterol (HDLC) ≤ 1.0 mmol/l male, ≤ 1.3 mmol/l female
* Glucose ≥ 6 mmol/l
* Stage 1 hypertension or above i.e. a systolic BP ≥ 140 mmHg, diastolic BP ≥ 90 mmHg
* BMI 28-35 kg/m2
* waist \>102 cm male or \> 84 cm female
* Adults with a first degree relative with either a history of premature CVD - age of onset younger than 55 y in fathers, sons or brothers or younger than 65 y in mothers, daughters or sisters, or type 2 diabetes.

Exclusion Criteria:

* having suffered a myocardial infarction/stroke in the past 12 months
* diabetic (diagnosed or fasting glucose \> 7 mmol/l) or suffer from other endocrine disorders
* suffering from renal or bowel disease or have a history of choleostatic liver or pancreatitis
* on drug treatment for hyperlipidaemia, hypertension, inflammation or hypercoagulation
* no history of alcohol abuse
* planning or on a weight reducing regime
* taking any fish oil, fatty acid or vitamin and mineral supplements
* pregnant, lactating or planning a pregnancy
* smokers

Primary outcomes:
measure: Percent Change in Flow Mediated Dilatation (FMD)
timeFrame: Baseline, 4 months
Secondary outcomes:
measure: Cardiovascular Risk Factors (Lipids, Inflammatory Markers, Indices of Insulin Resistance, Cell Microparticles, Endothelial Progenitor Cells)
timeFrame: 4 months
measure: 24-hour Ambulatory Blood Pressure
timeFrame: 4 months
measure: Vascular Stiffness by Pulse Wave Velocity (PWV), Pulse Wave Analysis (PWA) and Digital Volume Pulse (DVP)
timeFrame: 4 months
measure: Microvascular Reactivity (Laser Doppler Imaging With Iontophoresis)
timeFrame: 4 months
Other outcomes:
Locations:
city: Reading
country: United Kingdom
facility: Department of Food and Nutritional Sciences, University of Reading
state: Berkshire
city: Reading
country: United Kingdom
facility: University of Reading
state: Berkshire
Study officials:
affiliation: University of Reading
name: Julie A Lovegrove, BSc PhD RNutr
role: PRINCIPAL_INVESTIGATOR
References:
citation: Weech M, Altowaijri H, Mayneris-Perxachs J, Vafeiadou K, Madden J, Todd S, Jackson KG, Lovegrove JA, Yaqoob P. Replacement of dietary saturated fat with unsaturated fats increases numbers of circulating endothelial progenitor cells and decreases numbers of microparticles: findings from the randomized, controlled Dietary Intervention and VAScular function (DIVAS) study. Am J Clin Nutr. 2018 Jun 1;107(6):876-882. doi: 10.1093/ajcn/nqy018.
citation: Shatwan IM, Weech M, Jackson KG, Lovegrove JA, Vimaleswaran KS. Apolipoprotein E gene polymorphism modifies fasting total cholesterol concentrations in response to replacement of dietary saturated with monounsaturated fatty acids in adults at moderate cardiovascular disease risk. Lipids Health Dis. 2017 Nov 23;16(1):222. doi: 10.1186/s12944-017-0606-3.
citation: Vafeiadou K, Weech M, Altowaijri H, Todd S, Yaqoob P, Jackson KG, Lovegrove JA. Replacement of saturated with unsaturated fats had no impact on vascular function but beneficial effects on lipid biomarkers, E-selectin, and blood pressure: results from the randomized, controlled Dietary Intervention and VAScular function (DIVAS) study. Am J Clin Nutr. 2015 Jul;102(1):40-8. doi: 10.3945/ajcn.114.097089. Epub 2015 May 27.
citation: Weech M, Vafeiadou K, Hasaj M, Todd S, Yaqoob P, Jackson KG, Lovegrove JA. Development of a food-exchange model to replace saturated fat with MUFAs and n-6 PUFAs in adults at moderate cardiovascular risk. J Nutr. 2014 Jun;144(6):846-55. doi: 10.3945/jn.114.190645. Epub 2014 Apr 9.