DIT After RYGB - A Prospective Study (DIT RYGB)

Diet-induced Thermogenesis After Roux-en-Y Gastric Bypass - A Prospective Study

Bariatric surgery is the only satisfactory treatment for loss and weight maintenance in obese patients. This loss is a result of several factors that go beyond the simple anatomical abnormality of the gastrointestinal tract and may be the product of post-op energy expenditure changes. The respiratory quotient (RQ) and diet-induced thermogenesis (DIT) are important components of energy expenditure and possible changes in them can perform an important role in weight loss after Roux-en-Y Gastric Bypass (RYGB). Previously, we conducted a cross-sectional study where we measured the RQ and DIT in pre and post-op RYGB patients, which was published in the Surgery of Obesity and Related Diseases (SOARD) journal. The objective of this study is to perform a prospective analysis of these same variables (RQ and DIT), evaluating them in the same patients, when pre and postoperatively.

Study Overview

• Status: Completed
• Conditions: Obesity; Morbid Obesity; Bariatric Surgery
• Intervention / Treatment: Other: A standard mixed Meal

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • Distrito Federal
    • Brasilia, Distrito Federal, Brazil, 70390-108
      • Gastrocirurgia de Brasilia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Pre-op: Body mass index (BMI) ≥ 40 kg/m2 or BMI ≥ 35 kg/m2 with associated co-morbidities. Age > 18 years
• Post-op: Patients who underwent surgery ≥ 12 months by the Head Surgeon of the Gastrocirurgia de Brasilia Clinic;

Exclusion Criteria:

• Patients aged > 65 years. Severe heart and/or respiratory problems; Pregnant women.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: A standard mixed Meal; The standard mixed meal was composed of a chicken salad sandwich and 200ml of coconut water, totalling 260 kcal, distributed among carbohydrates (62%), proteins (12%) and lipids (26%).

Other: A standard mixed Meal; All patients underwent an indirect calorimetry test, after a 12-h period of fasting from food and water, avoiding intake of alcohol or coffee, and avoiding physical exercise and cigarettes the day before the examination. To examine possible changes in the thermogenic effect of food, patients received a standard mixed meal (200 ml coconut water and a chicken salad sandwich using whole wheat bread). They then repeated the test 20 min and 60 min after eating to obtain a reading of the metabolic rate by considering DIT and the RQ in the postprandial period.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-op DIT increase	A post-op increase in DIT is expected to be greater than in pre-op period and may be a positive predictor for weight loss during the post-op phase.	2 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-op RQ increase	A postprandial increase in RQ greater than that in the pre-op phase is expected showing improvement in carbohydrate metabolism after RYGB.	2 months

Collaborators and Investigators

• Sponsor: Silvia Leite Faria
• Investigators: Principal Investigator: Silvia L Faria, M.Science, Gastrocirurgia de Brasilia

Study record dates

Study Major Dates

• Study Start: August 1, 2012
• Primary Completion (Actual): October 1, 2012
• Study Completion (Actual): October 1, 2012

Study Registration Dates

• First Submitted: December 14, 2012
• First Submitted That Met QC Criteria: December 27, 2012
• First Posted (Estimate): January 3, 2013

Study Record Updates

• Last Update Posted (Estimate): January 3, 2013
• Last Update Submitted That Met QC Criteria: December 27, 2012
• Last Verified: December 1, 2012

More Information

Terms related to this study

• Keywords: Diet-induced Thermogenesis;; Respiratory Quotient;; Roux-en-Y Gastric Bypass;; Energy Expenditure.
• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Overweight; Body Weight; Obesity; Obesity, Morbid
• Other Study ID Numbers: 002 (University of CT Health Center)