Use of Indirect Calorimetry in Obesity

Use of Indirect Calorimetry in Dietary Setting in Obese Subjects: Retrospective Observational Study

The investigators will retrospectively analyze and compare data of 2 groups of overweight and obese patients: subjects who followed a diet based on Resting Energy Expenditure (REE) measured by indirect calorimetry and subjects who followed a diet based on REE estimated by the Harris-Benedict equation. Propensity score adjustment will be used to adjust for known differences between the 2 groups

Study Overview

• Status: Completed
• Conditions: Overweight and Obesity; Metabolism Disorder
• Intervention / Treatment: Diagnostic test: Indirect calorimetry

• Study Type: Observational
• Enrollment (Actual): 355

Contacts and Locations

Study Locations

• Italy
  • MI
    • San Donato Milanese, MI, Italy, 20097
      • San Donato Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 86 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

To collect clinical data of a total population comprising patients referred to our Endocrinology-Diabetes Outpatient Clinic, in the period from April 2012 through October 2016.

In this retrospective study, will be considered patients with an age ranging from 20 to 86 years, with overweight (25 ≤ BMI ≤ 29.9) or obesity (BMI ≥ 30), requiring dietary intervention for weight control.

Statistical analysis will perform on overweight and obese patients divided into two subgroups: IC group and NO-IC group.

Anthropometric status and metabolic biomarkers will re-evaluated at check-ups performed after 3 months, 6 months, 12 months and 18 months from the baseline.

Description

Inclusion Criteria:

• BMI >25
• Age ranging from 20 to 86 years

Exclusion Criteria:

• BMI<25
• Age <20
• Age >86

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Retrospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Indirect Calorimetry group (IC group); Group who performed indirect calorimetry. REE measured by indirect calorimetry.	Diagnostic test: Indirect calorimetry; Indirect calorimetry will be performed by using an open-circuit calorimeter (Sensor Medics, Italy). Indirect calorimetry is the reference method for energy expenditure determination. A canopy hood covered the patient's head and expired air is extracted by a pump to be analyzed by metabolic cart sensors; flow rate is directly measured with a digital turbine flowmeter. After an overnight fast, patients will asked to lay supine in complete physical rest, not sleeping or talking for approximately 20-25 minutes, at a room temperature ranged between 22 and 24°C. The mean REE for each participant considers the last 15-20 minutes of measurements corresponding to steady state. Software of calorimeter will be set for minute-by-minute reading report of VO2 (Oxygen flow) and VCO2 (Carbon dioxide flow) measurement. Parameters obtained by Indirect Calorimetry will be the Resting Energy Expenditure and the Respiratory Quotient (RQ)
NO Indirect Calorimetry group (NO-IC group); Group who did not perform indirect calorimetry. Resting Energy Expenditure calculated by Harris-Benedict formula

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Weight in Indirect Calorimetry group and in NO Indirect Calorimetry group	To compare body weight variation (kg) in two groups of overweight or obese patients: subjects who followed a diet formulated on REE measured by IC (IC group) and subjects who followed a diet based on REE predicted by the Harris-Benedict formula (NO-IC group)	18 months
BMI in Indirect Calorimetry group and in NO Indirect Calorimetry	To compare BMI variation (kg/m^2) in two groups of overweight or obese patients: subjects who followed a diet formulated on REE measured by IC (IC group) and subjects who followed a diet based on REE predicted by the Harris-Benedict formula (NO-IC group)	18 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Weight in male/female in Indirect Calorimetry group and in NO indirect Calorimetry group	To identify gender differences in weight variation (kg) between IC and NO-IC groups	18 months
BMI in male/female in Indirect Calorimetry group and in NO indirect	To identify gender differences in BMI variation (kg/m^2) between IC and NO-IC groups	18 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Weight in adequate to predicted REE and in NOT adequate to predicted REE subpopulations	to compare body weight variation (kg) in two sub-populations of the IC-group: subjects with adequate to predicted REE and subjects with not adequate to predicted REE	18 months
BMI in adequate to predicted REE and in NOT adequate to predicted REE subpopulations	to compare BMI variation in two sub-populations of the IC-group: subjects with adequate to predicted REE and subjects with not adequate to predicted REE	18 months
Weight in subjects with RQ<0.9 and subjects with RQ>0.9	to compare body weight variation in 2 subpopulation of the IC group: subjects with an RQ ≤ 0.9 and subjects with RQ > 0.9.	18 months
BMI in subjects with RQ<0.9 and subjects with RQ>0.9	BMI variation in 2 subpopulation of the IC group: subjects with an RQ ≤ 0.9 and subjects with RQ > 0.9.	18 months
Glucose in Indirect Calorimetry group and in NO Indirect Calorimetry Group	to identify differences in glucose (mg/dl) variation between IC and NO-IC groups	18 months
Tryglycerides in Indirect Calorimetry group and in NO Indirect Calorimetry Group	to identify differences in tryglycerides (mg/dl) variation between IC and NO-IC groups	18 months
Total cholesterol (mg/dl) in Indirect Calorimetry group and in NO Indirect Calorimetry Group	to identify differences in cholesterol variation between IC and NO-IC groups	18 months
Hemoglobin in Indirect Calorimetry group and in NO Indirect Calorimetry Group	to identify differences in glycated hemoglobin (%) variation between IC and NO-IC groups	18 months
Uric acid in Indirect Calorimetry group and in NO Indirect Calorimetry Group	to identify differences in uric acid (mg/dl) variation between IC and NO-IC groups	18 months

Collaborators and Investigators

• Sponsor: Ospedale San Donato
• Investigators: Principal Investigator: Livio Luzi, Professor, IRCCS Policlinico San Donato

Publications and helpful links

General Publications

• Massarini S, Ferrulli A, Ambrogi F, Macri C, Terruzzi I, Benedini S, Luzi L. Routine resting energy expenditure measurement increases effectiveness of dietary intervention in obesity. Acta Diabetol. 2018 Jan;55(1):75-85. doi: 10.1007/s00592-017-1064-0. Epub 2017 Nov 3.

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2012
• Primary Completion (Actual): October 31, 2016
• Study Completion (Actual): October 31, 2016

Study Registration Dates

• First Submitted: July 21, 2017
• First Submitted That Met QC Criteria: July 27, 2017
• First Posted (Actual): July 28, 2017

Study Record Updates

• Last Update Posted (Actual): July 28, 2017
• Last Update Submitted That Met QC Criteria: July 27, 2017
• Last Verified: July 1, 2017

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Overnutrition; Nutrition Disorders; Body Weight; Obesity; Overweight; Metabolic Diseases
• Other Study ID Numbers: CALO/Obesity

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