SARCOPEDIA - Sarcopenia Diagnostics in Aging Medicine

Musculoskeletal aging is one of the major responsibilities and challenges for public health. In particular, sarcopenia correlates with an increased risk of falls and increased morbidity and mortality. With regard to screening for sarcopenia, the guidelines of the European Working Group on Sarcopenia in Older People (EWGSOP2) refer to algorithmic case finding, diagnosis, and quantification of the severity of sarcopenia in clinical. While functional measurements are more difficult to standardize and associated with higher variability, Dual-energy X-ray absorptiometry (DXA) is considered a highly accurate method, even referred to as the "gold standard" to determine muscle mass in the scientific literature. Nevertheless, DXA, which is routinely used, shows inconsistent correlation with functional decline in muscle strength. Another method of muscle quantification is bioelectrical impedance analysis (BIA), a simple, portable instrument that is more readily available and applicable due to its lower cost. However, it tends to overestimate muscle mass and is also more susceptible to a person's hydration status. Because of these difficulties, recent research has focused on the potential of using shear wave elastography. This method indirectly serves to quantify the rapid type II muscle fibers in order to make statements about the muscle quality because an age-related decrease in type II muscle fibers is associated with a more frequent fall frequency. First, the investigators will define three different categories according to the EWGSOP 2 guidelines based on the muscle strength (grip strength, assessed by pneumatic hand dynamometer) and muscle mass (Appendicular skeletal muscle mass, assessed by BIA): "No Sarcopenia", "Probable Sarcopenia" and "Confirmed Sarcopenia". Within these categories, the Investigators would like to establish a multivariate data analysis of different functional measurements with quantitative imaging results. This exploratory trial design is intended to improve understanding within the three categories and to test proxy measurements of different patients who are ruled out for common routine measurements due to, for example, cognitive impairment or pre-existing rheumatic disease. This is essential to consider the heterogeneity of the aging society proportionally.