Evaluation of Different Methods to Measure Muscle Mass and Strength in a Population With Class II/III Obesity

Study Overview
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Brief Summary
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Rationale: Weight loss therapies should aim to reduce fat mass while preserving both muscle mass and muscle strength. Consequently, there is a need for validated methods to measure muscle mass and strength. Current methods are either expensive and require trained technicians, or have not been validated in populations with class II/III obesity (BMI > 35 kg/m2). In our previous studies (MUST-MOP and MUSCLE study), we have validated the use of ultrasound (US) for the measurement of lean mass (a proxy for muscle mass) in a population with obesity. These studies showed that the use of US for the measurement of lean mass was feasible, reliable and valid. The aim of the current study is to validate the use of US for the measurement of lean mass after weight loss in a population of bariatric surgery patients. Objective: Primary objective: To assess the validity of US to measure lean mass after weight loss in a population of bariatric surgery patients. Secondary Objectives: To assess de differences in lean mass between DXA and US in this study compared to the MUSCLE-study. To assess how the lean mass has changed after bariatric surgery and the effects of lean mass on total weight loss and resolution of comorbidities To assess whether the change in lean mass has an effect on serum levels of markers for muscle mass. Study design: This study is an observational follow-up study of the MUSCLE study and will take place in the Centre Obesity Northern-Netherlands (CON) at the Medical Centre Leeuwarden (MCL). Study population: The population will consists of participants, who have participated in the MUSCLE study and have received bariatric surgery at the CON / MCL. Main study parameters/endpoints: The main parameters of this study are: lean mass measured by DXA and US. The main endpoint of this study is the validity of the US measurement of lean mass compared to DXA. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: There are no direct benefits for the participants. However, the results of this study can help to further validate the ultrasound as a cheaper and more accessible method to measure muscle mass. This can potentially be used in standard clinical care to assess muscle mass of patients during weight loss. • The additional time investment: during first year follow-up appointment approximately 30 minutes. The risks of most test are minor, even the small amount of radiation exposure, which means the risks and burden of this study outweigh the potentially obtainable knowledge.

Official Title
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Evaluation of Different Methods to Measure Muscle Mass and Strength in a Population With Class II/III Obesity: A Follow-up Study

Conditions
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Obesity, Morbid

Intervention / Treatment
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* Device: Ultrasonography
* Radiation: Dual-energy X-ray Absorptiometry


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participation MUSCLE study ±1 year after bariatric surgery Exclusion Criteria: Inability to communicate in either Dutch or English Weight over 204 kilograms (due to limitations of the DXA) Pregnancy Pacemaker

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 67 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 1<br>The population will consist of patients, who have participated in the MUSCLE study and have received bariatric surgery at the CON / MCL. A potential subject who meets any of the following criteria will be excluded from participation in this study: Inability to communicate in either Dutch or English Weight over 204 kilograms (due to limitations of the DXA) Pregnancy Pacemaker | Device: Ultrasonography<br>* The US muscle measurement will be performed with the handheld portable Philips Lumify Sonography connected to a Samsung tablet. The measurement will take approximately 5-10 minutes. A seven-point measurement has to be performed based on the seven-site Jackson Pollock Generalized Prediction Equations for circumference and skinfold thickness measurements.6,7<br>* Other names: ultrasound;Radiation: Dual-energy X-ray Absorptiometry<br>* The brand of the DXA scanner is the Hologic Discovery A, which has a weight limit of 204 kilograms. During the DXA scan, patients will be exposed to radiation, which is approximately 0.2 micro Sievert (µSv) for measuring body composition. For comparison: the average amount of background radiation per hour is approximately 0.23 µSv. The DXA body composition scan will be performed according to standard protocol by a specialized technician.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| lean mass measured by dual-energy X-ray absorptiometry | gold standard | 1 time, 1 year after surgery | 
| lean mass measured by ultrasound | using LLM7 and LLM3 formulas | 1 time, 1 year after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| weight loss after surgery | total weight loss and excess weight loss (after bariatric surgery) | 1 time, 1 year after surgery | 
| change in lean mass | after bariatric surgery | 1 time, 1 year after surgery | 
| comorbidity status | Number of patients with resolution, improvement, same/worsened of comorbidities | 1 time, 1 year after surgery | 
| blood parameters (e.g. CK, CRP, cystatin C, myoglobine) | Concentration of blood parameters (e.g. CK, CRP, cystatin C, myoglobine) | 1 time, 1 year after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Muscle mass, Sonography