Introduction
The reduction of muscle mass in humans is obvious after the age of fifty, with a reduction
rate of 3-8% every ten years. The rate of loss accelerates with chronic diseases, sedentary
lifestyle, low physical activity, nutritional, environmental and socioeconomic factors .
Sarcopenia has been officially recognized as a disease according to World Health
Organization. European Working Group on Sarcopenia in Older People 2 has revised the
definition and diagnostic criteria of sarcopenia aiming to encourage more research in the
field. In Greece, there are no reference values for muscle strength and muscle mass. Defining
these values will permit the investigators to provide a tool that will help to establish
country - specific measurements of sarcopenia in Greek population.
Study population-Methods
The study site will be the Outpatient Geriatric Assessment Unit and the Radiology Department
of Henry Dunant Hospital Centre, in Athens-Greece.
The study population will be healthy adults that meet the inclusion criteria. The recruitment
will be performed using the snowball sampling technique (for instance, through printed
material, the marketing department of the hospital, social media, advertising banners, etc.).
Stratified random sampling technique will be used to achieve a representative sample size.
Evaluation of the appendicular muscle mass of the limbs will be performed by Dual-Energy
X-ray Absorptiometry, using a QDR-4500 A fan Beam densitometer (Hologic, Inc., Bedford, MA).
Hologic Discovery W configured with software version 12.1 (Hologic, Bedford, MA).
Body composition analysis will be evaluated with TANITA Body Composition Analyzer
device,model BC-418MA. Analysis concerns calculation of body consistency (body fat mass, lean
mass water and predicted muscle mass) using Bioelectric Impedance Analysis. Bioelectric
Impedance Analysis measures the body composition using a constant power source (high
frequency current 50kHz, 90 μA).
Muscle mass will also be measured by ultrasound -U/S. U/S determines the thickness and
transverse incisions of a superficial muscle group. It can measure basic parameters such as
muscle volume and spectrum length through the B-Mode imaging with Linear 7-12MHz frequency
heads that can reliably determine the thickness and transverse incisions of the superficial
muscular Groups.
Statistical analysis
It will be performed using the Statistical Package for the Social Sciences -SPSS Version 26.0
(IBM), and R Version 3.6.2.
Descriptive statistics will be presented in percentage proportions, mean values and Standard
Deviations (SD) of the variables. In addition, Z-score will be calculated (e.g. Dual-energy
X-ray absorptiometry , Bone Mineral density, Dual-energy X-ray absorptiometry % fat, etc.)
and T-score ± 2 standard deviations.
Chi-square - χ2 tests or non-parametric tests will be produced to compare qualitative
variables. T-test, Analysis of Variance- ANOVA and non-parametric tests will be used in the
statistical analysis of quantitative variables within the categories of qualitative
variables.
Approval
The protocol has been approved by the Scientific Committee of the Henry Dunant Hospital
Centre, in Athens -Greece, and is in accordance with the Code of Ethics of the World
Organization for Medical Sciences (CIOMS) as formulated in the Helsinki Declaration on
Biological Research.
Informed consent
All participants will be informed in written for the purpose of the research, and the way
their personal data are processed (name, address, telephone, e-mail), under the provisions of
2016/679 according to the General Data Protection Regulation (GDPR).
The consent form will describe the legal and transparent way of processing their data,
stating the specific purpose for data collection, as well as information about storage of
their data. It will also contain a written description of the rights of the participants
concerning their data and their ability to revoke consent for the processing of their data.
The processing, transfer and storage of data, will also be described, as well as who will
have access to their data, and how long the data will be stored for.
Finally, all participants will sign the written informed consent and confidentiality form.