Clinical trial NCT02616276: Postprandial Effect of Breakfast Glycemic Index on Vascular Function, Insulinemia and Cognitive Performance (BGI Study)
Official title: Postprandial Effect of Breakfast Glycemic Index on Vascular Function, Insulinemia and Cognitive Performance, a Crossover Clinical Trial (BGI Study)
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: Glycemic Index
Postprandial Period
Vascular Stiffness
Blood glucose
Cognition
Lead sponsor: Fundacion para la Investigacion y Formacion en Ciencias de la Salud
Sponsor class: OTHER
Collaborators: name: Castilla-León Health Service
First posted: 2015-11-26
Enrollment: 40
Sex: ALL
Minimum age (years): 20
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: OTHER

Brief summary: This is a crossover clinical trial aimed at adults (aged 20-40 years, with no cardiovascular disease), selected by consecutive sampling at urban primary care health clinics in Salamanca (Spain). Each subject will complete three interventions, with a washout period of one week: control breakfast (water), low glycemic index breakfast (apple, yogurt, walnuts and black chocolate) and high glycemic index breakfast (grape juice, bread and strawberry jam). The postprandial effect will be assessed at 60 and 120 minutes from each breakfast, measuring blood glucose and insulin and cognitive performance. Measurements will be performed of central blood pressure, augmentation index, pulse wave velocity, cardiac output and total peripheral vascular resistance at minutes (-10, 0, +15, +30, +45, +60, +75, +90, +105 and +120).

Detailed description: Objectives:

The primary objective of this study is to evaluate the postprandial effect of low and high glycemic index breakfasts on vascular function, measured by central blood pressure, augmentation index and pulse wave velocity, in a sample of healthy young adults. The second objective is to assess the postprandial effect of low and high glycemic index breakfasts on blood glucose and insulin values in a sample of healthy young adults. The third and last objective is to assess the postprandial effect of low and high glycemic index breakfasts on cognitive performance in a sample of healthy young adults.

Design and setting:

A controlled crossover clinical trial, where each subject will complete three interventions (control breakfast, high glycemic index breakfast and low glycemic index breakfast), with a washout period of one week between each, and whose order will be determined by a randomization sequence generated using the Randomization.com software (http://www.randomization.com).

Study setting:

The study will be conducted in the primary care health area of Salamanca in the Research Unit of La Alamedilla, belonging to the Spanish Network for Preventive Activities and Health Promotion (redIAPP) and Salamanca Institute for Biomedical Research (IBSAL).

Study population:

The subjects of the study population will be selected by consecutive sampling in the primary care clinics of urban health centers in Salamanca (Spain) between 2015 and 2016. As this crossover clinical trial, a consecutive sampling will ensure comparability of the groups.

Intervention:

Each of the three scheduled visits will last approximately 2 and a half hours, and will be structured as follows:

Min -10: Measurement of clinical blood pressure, central blood pressure, and central hemodynamic parameters; evaluation of cognitive performance; laboratory test sampling to determine glucose and insulin blood levels.

Min 0: Measurement of central blood pressure and central hemodynamic parameters; intake of assigned breakfast (10 minutes).

Min +15, +30, +45: Measurement of central blood pressure and central hemodynamic parameters.

Min +60: Measurement of central blood pressure and central hemodynamic parameters; evaluation of cognitive performance; laboratory test sampling to determine glucose and insulin blood levels.

Min +75, +90, +105: Measurement of central blood pressure and central hemodynamic parameters.

Min +120: Measurement of central blood pressure and central hemodynamic parameters; evaluation of cognitive performance; laboratory test sampling to determine glucose and insulin blood levels.

Eligibility criteria: Inclusion Criteria:

* Young adults.
* Aged between 20 and 40 years.
* Both sexes.
* Those agree to sign the informed consent.

Exclusion Criteria:

* History of cardiovascular events (acute myocardial infarction, stroke, etc.).
* History of hypertension, diabetes mellitus or dyslipidemia.
* Pharmacological treatment for any of the above conditions.
* Diagnosis of clinically demonstrable neurological and/or neuropsychological disease.
* Excessive consumption of toxic substances.
* Celiac patients and/or those intolerant to lactose.
* Subjects on a low-calorie and/or low-sodium diet.
* Pregnant women.
* Those with any other circumstance that the investigators consider could interfere with the study procedures.

Primary outcomes:
measure: Augmentation index
timeFrame: Changes in augmentation index at 1 week, according to glycemic index of the breakfast
Secondary outcomes:
measure: Central blood pressure
timeFrame: Changes in central blood pressure at 1 week, according to glycemic index of the breakfast
measure: Pulse wave velocity
timeFrame: Changes in pulse wave velocity at 1 week, according to glycemic index of the breakfast
measure: Blood glucose
timeFrame: Changes in blood glucose at 1 week, according to glycemic index of the breakfast
measure: Insulin values
timeFrame: Changes in insulin values at 1 week, according to glycemic index of the breakfast
measure: Immediate verbal memory
timeFrame: Changes in immediate verbal memory at 1 week, according to glycemic index of the breakfast
measure: Delayed verbal memory
timeFrame: Changes in delayed verbal memory at 1 week, according to glycemic index of the breakfast
measure: Phonological fluency
timeFrame: Changes in phonological fluency at 1 week, according to glycemic index of the breakfast
measure: Attention
timeFrame: Changes in attention at 1 week, according to glycemic index of the breakfast
measure: Processing speed
timeFrame: Changes in processing speed at 1 week, according to glycemic index of the breakfast
measure: Executive functions
timeFrame: Changes in executive functions at 1 week, according to glycemic index of the breakfast
measure: Working memory
timeFrame: Changes in working memory at 1 week, according to glycemic index of the breakfast
measure: Sustained attention
timeFrame: Changes in sustained attention at 1 week, according to glycemic index of the breakfast
measure: Selective attention
timeFrame: Changes in selective attention at 1 week, according to glycemic index of the breakfast
Other outcomes:
Locations:
city: Salamanca
country: Spain
facility: Primary Care Research Unit - The Alamedilla Center for Health
Study officials:
References:
citation: Sanchez-Aguadero N, Garcia-Ortiz L, Patino-Alonso MC, Mora-Simon S, Gomez-Marcos MA, Alonso-Dominguez R, Sanchez-Salgado B, Recio-Rodriguez JI. Postprandial effect of breakfast glycaemic index on vascular function, glycaemic control and cognitive performance (BGI study): study protocol for a randomised crossover trial. Trials. 2016 Oct 24;17(1):516. doi: 10.1186/s13063-016-1649-x.