Effect of a Kefir Beverage on Immunity and Lipid Profile

Effect of a Kefir Beverage on Immunity and Lipid Profile: An Exploratory Cluster Randomized Controlled Trial

This is an exploratory cluster randomized controlled trial to evaluate the effect of a kefir beverage, enriched with prebiotics components, on immunity, lipid profile and adiposity in a population-based study, using the family as the intervention unit.

Study Overview

• Status: Completed
• Conditions: Prebiotics
• Intervention / Treatment: Dietary supplement: Prebiotic group; Dietary supplement: Placebo group

Detailed Description

The gastrointestinal tract is populated by a collection of microorganisms, primarily bacteria, that interact with intestinal host cells. In the past two decades, several studies have demonstrated the effects of the intestinal microbiota on host physiological, metabolic and immunological processes and have revealed that the microbiota is fundamental to host body function. There is currently a growing interest in manipulating the intestinal microbiota to enhance the effects on health and welfare of the intestine. In this regard, since its introduction, the concept of prebiotics has stimulated both scientific and industrial interest. A dietary prebiotic is a selectively fermented ingredient that results in specific changes, in the composition and/or activity of the gastrointestinal microbiota, thus conferring benefits upon host health. To date, the prebiotics most widely evaluated in human clinical trials are inulin-type fructans (inulin, fructo-oligosaccharides, oligofructose) and galacto-oligosaccharides (GOS).

The investigators goal is to conduct a human clinical trial to evaluate the impacts of a functional-prebiotic beverage on immunity and metabolic profile.

This study will be performed on a family-oriented basis. 44 families/clusters (~ 150 children and adults, older than 3 years) will be selected to participate in the study and will be randomized into intervention group (n=22 families) and control (n=22 families) groups.

Weight, body mass index (BMI), waist circumference (WC), nutrient intake from food frequency questionnaire, physical activity, blood pressure, allergic sensitization, metabolic function (fasting blood glucose, HbA1c, insulin resistance and lipid profile), general lymphocyte overview (B-cells, T-cells and NK-cells) and sub-populations of T-helper cells (Th1, Th2, Th17 and T-regulatory), inflammation markers (C-reactive protein, interleukin-6 and tumor necrosis factor-alpha) will be measured at baseline and after 4 months.

Mixed effect models analysis will be performed to assess changes in the cardiometabolic and immune parameters.

• Study Type: Interventional
• Enrollment (Actual): 158
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Spain
  • Pontevedra
    • A Estrada, Pontevedra, Spain, 36680
      • A Estrada Primary Care Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 3 years to 85 years (Child, Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. For the index subject:

   • Female or male.
   • 18 years and older.
   • Living in a family unit with two or more people.

2. For the other family members:

   • Female or male.
   • Age between 3 to 85 years.
3. At family level: at least two members will meet inclusion criteria but no exclusion criterion

Exclusion Criteria for the index subject and the other family members:

• Alcoholism
• Pregnant
• Major cardiovascular disease
• Dementia
• Major autoimmune diseases
• Diseases or treatments that seriously affect the immune status
• Neoplasia
• Terminal disease

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Prebiotic group.; Group of 22 families consuming a fermented dairy product with prebiotic components, once a day for 4 months.	Dietary supplement: Prebiotic group; Fermented dairy product with galacto-oligosaccharides (GOS), kefiran and other metabolites resulting from the fermentation with kefir granules.; Other Names: Fermented dairy product with kefir granules
Placebo Comparator: Placebo group; Group of 22 families consuming a dairy product with similar characteristics regarding color, flavor and nutritional composition, not containing the prebiotic components, once a day for 4 months.	Dietary supplement: Placebo group; Beverage with color, flavor and nutritional composition similar to the fermented dairy product but not containing the prebiotic components.; Other Names: Dairy product without prebiotic components

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline in Th17 cell counts in peripheral blood	Flow cytometry analysis on peripheral blood	4 months
Change from baseline in CD4 positive regulatory T cell counts in peripheral blood	Flow cytometry analysis on peripheral blood	4 months
Change from baseline in Th1 cell counts in peripheral blood	Flow cytometry analysis on peripheral blood	4 months
Change from baseline in Th2 cell counts in peripheral blood	Flow cytometry analysis on peripheral blood	4 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change from baseline in total cholesterol	Enzymatic method using standard kits on an Advia 2400 Clinical Chemistry System (Siemens Healthcare Diagnostics)	4 months
Change from baseline in HDL cholesterol	Enzymatic method using standard kits on an Advia 2400 Clinical Chemistry System (Siemens Healthcare Diagnostics)	4 months
Change from baseline in LDL cholesterol	Estimated using the Friedewald formula. Enzymatic method when triglycerides > 400 mg/dl.	4 months
Change from baseline in triglycerides	Enzymatic method using standard kits on an Advia 2400 Clinical Chemistry System (Siemens Healthcare Diagnostics)	4 months
Change from baseline in allergic sensitization measured through a battery of 11 skin prick test to common allergens	Cases with at least one positive test will be considered to have allergic sensitization.	4 months
Change from baseline in B lymphocytes in peripheral blood	Flow cytometry analysis on peripheral blood	4 months
Change from baseline in T lymphocytes in peripheral blood	Flow cytometry analysis on peripheral blood	4 months
Change from baseline in Natural Killer (NK) lymphocytes in peripheral blood	Flow cytometry analysis on peripheral blood	4 months
Change from baseline in C-reactive protein	Immunometric chemoluminiscence method employing an Immulite 2000 Immunoassay System	4 months
Change from baseline in interleukin-6	Immunometric chemoluminiscence method employing an Immulite 2000 Immunoassay System	4 months
Change from baseline in tumor necrosis factor-alpha	Immunometric chemoluminiscence method employing an Immulite 1000 Immunoassay System	4 months
Change from baseline in glucose	Enzymatic method using standard kits on an Advia 2400 Clinical Chemistry System (Siemens Healthcare Diagnostics)	4 months
Change from baseline in HbA1c	High resolution liquid chromatography using a Menarini Diagnostics HA-8160 Analyzer;	4 months
Change from baseline in insulin	Immunometric chemoluminiscence method employing an Immulite 2000 Immunoassay System	4 months
Change from baseline in body mass index (BMI)	BMI will be calculated as body weight (kg) divided by height (m) squared. The BMI of subjects under 18 years of age will be standardised using World Health Organization (WHO) reference data.	4 months
Change from baseline in waist circumference	Waist circumference will be measured at the narrowest point between the bottom rib and the top of the iliac crest.	4 months
Change from baseline in hip circumference	Hip circumference will be measured at the point of greatest prominence of the gluteal muscles.	4 months
Change from baseline in stool frequency	Evaluated through a questionnaire.	4 months
Change from baseline in stool consistency (Bristol Stool Form Scale score)	Bristol Stool Form Scale (BSFS) is for classifying the form of stool into 7 categories scored from 1 to 7; (1) Separate hard lumps like nuts (difficult to pass); (2) Sausage-shaped but lumpy; (3) Like a sausage but with cracks on its surface; (4) Like a sausage or snake, smooth and soft; (5) Soft blobs with clear-cut edges (passed easily); (6) Fluffy pieces with ragged edges, a mushy stool; (7) Watery, no solid pieces, entirely liquid. Subjects choose one of the BSFS scores which has a nearest analog form with their stools at every defecation. Types 1 and 2 are considered to be abnormally hard stools, while Types 6 and 7 are considered abnormally liquid stools. Types 3, 4 and 5 are generally considered to be the most normal stool forms.	4 months
Change from baseline in food intake over the last 4 weeks	Assessed using a semi-quantitative food frequency questionnaire (FFQ) which include 93 foods and drinks habitually consumed in Spain.	4 months

Collaborators and Investigators

• Sponsor: Hospital Clinico Universitario de Santiago
• Collaborators: Ministerio de Economía y Competitividad, Spain
• Investigators: Study Chair: Mar Calvo-Malvar, PhD, Clinic University Hospital of Santiago, Santiago de Compostela, Spain.

Study record dates

Study Major Dates

• Study Start (Actual): April 10, 2017
• Primary Completion (Actual): November 23, 2017
• Study Completion (Actual): November 27, 2017

Study Registration Dates

• First Submitted: October 4, 2017
• First Submitted That Met QC Criteria: October 12, 2017
• First Posted (Actual): October 18, 2017

Study Record Updates

• Last Update Posted (Actual): March 5, 2018
• Last Update Submitted That Met QC Criteria: March 2, 2018
• Last Verified: March 1, 2018

More Information

Terms related to this study

• Keywords: Prebiotics; kefir
• Other Study ID Numbers: INNTER BIOFUNCIOGAL 2015

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No