Glucose, Brain and Microbiota

NCT03889132 | Completed

• 1 other identifier: IRONMET+CGM-2017.139
• Study Type: observational
• Target: 128
• Locations: 1 country
• Sites: 1

Brief Summary

The accumulation of iron is known to affect the functions of the liver, adipose tissue and muscle. The brain is a well-known place of iron deposition, which is associated with cognitive parameters of subjects with obesity. The hypothesis is that certain parameters related to glucose metabolism (glycemic variability, the circulating concentration of AGE receptor agonists, pentosidine and HbA1c) are associated with cognitive function, brain iron content and gut microbiota composition in subjects with obesity. The study includes both a cross-sectional (comparison of subjects with and without obesity) and a longitudinal design (evaluation one year after weight loss induced by bariatric surgery or by diet in patient with obesity) to evaluate the associations between continuous glucose monitoring, brain iron content (by magnetic resonance), cognitive function (by means of cognitive tests), physical activity (measured by activity and sleep tracker device) and the composition of the microbiota, evaluated by metagenomics.

Conditions

Obesity

Keywords

Obesity; Continous Glucose Monitoring; Cognition; Brain Iron content

Outcome Measures

Primary Outcomes (9)

• Concentration of advanced glycation end products (AGE) receptor agonists.

  Enzyme-linked immunosorbent assay (ELISA).

  30 months

• Glycemic variability.

  Mean and standard deviation of glucose measures in mg/dL using a continuous glucose monitoring during 10 days.

  30 months

• The percentage of time in glucose target range (glucose level 100mg/dl-125mg/dl)

  30 months

• The glycaemic risk measured with low blood glucose index (LBGI)

  Low blood glucose index (LBGI) is a parameter that quantifies the risk of glycaemic excursions in non-negative numbers.

  30 months

• The glycaemic risk measured with high blood glucose index (HBGI)

  High blood glucose index (HBGI) is a parameter that quantifies the risk of glycaemic excursions in non-negative numbers.

  30 months

• The glycaemic variability measured with mean amplitude of glycaemic excursions (MAGE)

  measured in mg/dl

  30 months

• Minutes light sleep

  Mean and standard deviation of minutes light sleep measures by activity and sleep tracker device.

  30 months

• Minutes deep sleep

  Mean and standard deviation of minutes deep sleep measures by activity and sleep tracker device.

  30 months

• Minutes rapid eye movement (REM)

  Mean and standard deviation of minutes REM measures by activity and sleep tracker device.

  30 months

Secondary Outcomes (43)

• Effect on brain structure.

  30 months

• Effect on gut microbiota.

  30 months

• Changes from baseline in circulating concentration of AGE receptor agonists and glycemic variability one year of follow-up after weight loss in association with changes in brain structure and gut microbiota.

  30 months

• Cognitive impairment

  30 months

• Audioverbal memory

  30 months

Study Arms (6)

Premenopausal women with obesity

Procedure: Bariatric Surgery

Postmenopausal women with obesity

Procedure: Bariatric Surgery

Men with obesity

Procedure: Bariatric Surgery

Premenopausal women without obesity

Postmenopausal women without obesity

Men without obesity

Interventions

Bariatric Surgery PROCEDURE

Subjects with obesity (N=60) will be undertaken a hypocaloric diet and a periodic follow up, also 30 of them will undergo bariatric surgery

Men with obesity; Postmenopausal women with obesity; Premenopausal women with obesity

Eligibility Criteria

• Age: 30 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients with obesity, without known type 2 diabetes, previously scheduled at the Service of Endocrinology, Diabetes and Nutrition (UDEN) of the Hospital "Dr. Josep Trueta" of Girona (Spain) will be recruited and studied. Subjects without obesity will also be recruited through a public announcement.

You may qualify if:

• Men and women aged 30-65 years.
• Informed consent for participation in the study.

You may not qualify if:

• Serious systemic disease unrelated to obesity such as cancer, severe kidney, or liver disease, known type 1 or type 2 diabetes.
• Systemic diseases with intrinsic inflammatory activity such as rheumatoid arthritis, Crohn's disease, asthma, chronic infection (e.g., HIV, active tuberculosis) or any type of infectious disease.
• Pregnancy and lactation.
• Patients with severe disorders of eating behaviour.
• Persons whose liberty is under legal or administrative requirement.
• Clinical symptoms and signs of infection in the previous month.
• Antibiotic, antifungal or antiviral treatment in the previous 3 months.
• Anti-inflammatory chronic treatment with steroidal and/or non-steroidal anti-inflammatory drugs.
• Major psychiatric antecedents.
• Excessive alcohol intake, either acute or chronic (alcohol intake greater than 40 g a day (women) or 80 g/day (men)) or drugs abuse.
• Serum liver enzymes (AST, ALT) activity over twice the upper limit of normal.
• History of disturbances in iron balance (e.g., genetic hemochromatosis, hemosiderosis from any cause, atransferrinemia, paroxysmal nocturnal hemoglobinuria).

Sponsors & Collaborators

• Institut d'Investigació Biomèdica de Girona Dr. Josep Trueta: lead

Study Sites (1)

Institut d'Investigació Biomèdica de Girona (IDIBGI)

Girona, Girona, 17007, Spain

Location

Related Publications (28)

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MeSH Terms

Conditions

Obesity

Interventions

Bariatric Surgery

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Bariatrics; Obesity Management; Therapeutics; Surgical Procedures, Operative

Study Officials

• José Manuel Fernández-Real, M.D., Ph.D.

  Institut d'Investigació Biomèdica de Girona Dr. Josep Trueta

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal investigator, clinical professor, section chief of Endocrinology and Nutrition Department of Josep Trueta University Hospital

Study Record Dates

• First Submitted: February 27, 2019
• First Posted: March 26, 2019
• Study Start: March 5, 2019
• Primary Completion: July 31, 2022
• Study Completion: May 31, 2025
• Last Updated: March 31, 2026

Record last verified: 2026-03

Locations

ES (1)