Body Composition, Ultrasound
Conditions
Keywords
reliability, bioelectrical impedance analysis, computed tomography, strength, mobility
Brief summary
The prospective study will include 200 patients and 50 critically ill patients, who had an abdominal computed tomography (CT) scan including the L3 level for any clinical reason. Ultrasound scans of the anterior thighs and forearms will be taken after the CT scan within 48 hours. Bioelectrical impedance analysis (BIA) will also be performed. In addition muscle strength, mobility, physical function and nutrition will be assessed. Primary outcome is the prediction of CT-based whole body muscle and fat volume and BIA-based fat and lean body mass from ultrasound-based muscle and fat thickness. Other secondary outcomes include the intra- and interrater reliability of the CT evaluation and ultrasound examination of muscle and fat mass. The relationship between clinical aspects (strength, mobility, physical function, nutrition) and whole body composition is another secondary outcome.
Interventions
Body composition measurements comprise the ultrasound measurement of fat and muscle thickness of both upper arms and thighs, the bioelectrical impedance analysis (BIA), measurement of weight, handgrip strength, overall muscle strength (Medical Research Council scale) and questionnaires about physical activity, nutrition and fluid status.
Sponsors
Medical University of Vienna
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* cross-sectional abdominal CT scan including the level of L3 vertebra for any clinical reason * study-related ultrasound examination must take place within 48 hours of CT
Exclusion criteria
* patients younger than 18 years
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| prediction (r2) of CT-based whole body muscle volume from ultrasound-based muscle thickness | Ultrasound measurement once-only within 48 hours after the CT scan | In a linear regression model, the dependent variable is CT-based whole body muscle volume. The independent variable is ultrasound-based muscle thickness. The prediction (r2) of CT-based muscle volume in the multiple linear regression model is the outcome. |
| prediction (r2) of CT-based whole body fat volume from ultrasound-based fat thickness | Ultrasound measurement once-only within 48 hours after the CT scan | In a linear regression model, the dependent variable is CT-based whole body fat volume. The independent variable is ultrasound-based fat thickness. The prediction (r2) of CT-based fat volume in the multiple linear regression model is the outcome. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| intrarater reliability (bias in Bland Altman analysis) of ultrasound muscle/fat thickness | repeated US measurement in 60 patients once-only within 48 hours after the CT scan | For intrarater reliability each of the 5 examiners repeats the ultrasound measurement in 12 patients. In a Bland Altman analysis, the mean difference (=bias) in muscle/fat thickness between repeated measurements of the same examiner is the outcome. |
| prediction (r2) of BIA-based whole body muscle volume from ultrasound-based muscle thickness | BIA measurement once-only within 48 hours after the CT scan | In a linear regression model, the dependent variable is BIA-based whole body muscle volume. The independent variable is ultrasound-based muscle thickness. The prediction (r2) of BIA-based muscle volume in the multiple linear regression model is the outcome. |
| muscle strength in patients with different CT-based body compositions (sarcopenia, malnutrition, obesity, sarcopenic obesity) | muscle strength measurement once-only within 48 hours after the CT scan | Muscle strength is measured with MRC scale and hand dynamometry. The outcome is muscle strength evaluated in different patient's group according to their CT-based body composition. Sarcopenia is defined as lowered L3 skeletal muscle index. Malnutrition is defined at a BMI beneath18,5 kg/m². Obesity is defined as a BMI above or equal to 30 kg/m². Sarcopenia obesity is defined as lowered L3 skeletal muscle indices and a BMI above or equal to 30 kg/m2. |
| interrater reliability (bias in Bland Altman analysis) of ultrasound muscle/fat thickness | repeated US measurement in 60 patients once-only within 48 hours after the CT scan | For interrater reliability each of the 10 different pairs of examiners analyzes 6 patients. For each pair both examiners perform the ultrasound examination. In a Bland Altman analysis, the mean difference (=bias) in ultrasound muscle/fat thickness between examiners is the outcome. |
| prediction (r2) of BIA-based whole body fat volume from ultrasound-based fat thickness | BIA measurement once-only within 48 hours after the CT scan | In a linear regression model, the dependent variable is BIA-based whole body fat volume. The independent variable is ultrasound-based fat thickness. The prediction (r2) of BIA-based fat volume in the multiple linear regression model is the outcome. |
Countries
Austria
Outcome results
None listed