Effect of MEDiterranean Diet on the microBIOME of Individuals With Type 2 Diabetes (MEDBIOME)

Dysbiosis of gut microbiota is associated with the pathophysiology of type 2 diabetes. Mediterranean diet has been indicated as a dietary pattern that promote the integrity of gut barrier and that has positive impact in the metabolic control of subjects with type 2 diabetes. This is a 12-week, single-arm clinical study that aims to evaluate if the effect of Mediterranean diet in metabolic control of these subjects is mediated by gut microbiota. Subjects will receive personalized nutrition counseling where Mediterranean diet will be promoted.

Study Overview

• Status: Unknown
• Conditions: Type 2 Diabetes
• Intervention / Treatment: Other: Individualized structured dietary plan based on MD

• Study Type: Interventional
• Enrollment (Anticipated): 30
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Conceição Calhau; Phone Number: +351218803000; Email: ccalhau@nms.unl.pt

Study Locations

• Portugal
  • Lisbon, Portugal, 1169-056
    • Recruiting
    • NOVA Medical School|Faculdade de Ciências Médicas, Universidade NOVA de Lisboa
    • Contact: Conceição Calhau; Phone Number: +351918482491; Email: diabeer@nms.unl.pt

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 40 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Men and women diagnosed with type 2 diabetes mellitus, according to the American Diabetes Association criteria;
• Ages 40-80 years;
• Non-smoker;
• Willing and able to provide written informed consent.

Exclusion Criteria:

• Diabetes diagnosed before 40 years old;
• Changes in oral glycaemic-control medications in the last 3 months;
• Subjects with HbA1c levels under 6.4% or above 10%;
• Subjects under insulinotherapy;
• Subjects under corticotherapy;
• Subjects with triglycerides levels above 4.52 nmol/L (400 mg/dL);
• Intake of antibiotics in the last 12 weeks;
• Subjects with a diagnosis of any digestive disease including functional bowel disorders such as IBS.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Individualized structured dietary plan based on MD; Participants will follow an individualized structured dietary plan based on Mediterranean diet for 12 weeks	Other: Individualized structured dietary plan based on MD; Participants will follow an individualized structured dietary plan based on Mediterranean diet for 12 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in intestinal microbiota from baseline to visit 2 and 3	Bacterial DNA will be extracted from fecal samples. 16SRNA gene will be sequenced by next-generation sequencing (NGS). All the identified bacterial phyla, genus and species will be expressed in percentage	1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2) and 12-week post Mediterranean diet intervention (visit 3)
Changes in HbA1c levels (percent) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in HOMA-IR from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in HOMA-B (percent) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in HOMA-S (percent) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in fasting capillary blood glucose (mg/dL) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in fasting insulin (μU/mL) levels from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in diet quality from baseline to visit 3	Mediterranean diet adherence will be evaluated using the Mediterranean Diet Adherence Screener (MEDAS) from the PREvención com Dieta MEDiterránea (PREDIMED) study. Responses that are favorable to the adoption of the Mediterranean diet are scored as 1 point, while responses that are unfavorable are scored as 0. The final score ranged between 0 and 14 and a MEDAS score greater than 9 indicates high adherence to the Mediterranean diet.	1-week post run-in period (baseline), 12-week post Mediterranean diet intervention (visit 3)
Changes in food intake from baseline to visit 2 and 3	3 non-consecutive 24-h dietary food recall using a photographic manual for food quantification	1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in fasting serum total cholesterol (mg/dL) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in fasting serum high-density lipoprotein (HDL) (mg/dL) cholesterol from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in fasting serum low-density lipoprotein (LDL) (mg/dL) cholesterol from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in fasting serum triglycerides (mg/dL) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in total body fat mass (kg) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in free fat mass (kg) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)
Changes in waist perimeter (cm) from baseline to visit 2 and 3		1-week post run-in period (baseline), 4-week post Mediterranean diet intervention (visit 2), 12-week post Mediterranean diet intervention (visit 3)

Collaborators and Investigators

• Sponsor: Universidade Nova de Lisboa

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2019
• Primary Completion (Anticipated): July 31, 2021
• Study Completion (Anticipated): September 30, 2021

Study Registration Dates

• First Submitted: May 20, 2020
• First Submitted That Met QC Criteria: May 25, 2020
• First Posted (Actual): May 27, 2020

Study Record Updates

• Last Update Posted (Actual): May 27, 2020
• Last Update Submitted That Met QC Criteria: May 25, 2020
• Last Verified: May 1, 2020

More Information

Terms related to this study

• Keywords: Type 2 diabetes; Gut microbiota; Mediterranean diet
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Endocrine System Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 2
• Other Study ID Numbers: MEDBIOME

Drug and device information, study documents

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