The usefulness of muscle architecture assessed with ultrasound to identify hospitalized older adults with physical decline.

BACKGROUND: Muscle mass and strength decline are known to be key factors in the development of physical incapacities in later life. These structural and functional declines are even more significant in older people during hospitalizations, increasing risk of falls, fractures, and loss of quality of life. In clinical daily practice, functional and muscular decline are assessed using the validated Short Physical Performance Battery (SPPB). Nevertheless, psychological conditions (pain, demotivation, depression) and temporary physical incapacities (e.g: hip fracture) during hospitalization can be significant barriers to evaluate these patients. Skeletal muscle ultrasound assessment could be an alternative in clinical daily practice since muscle architecture (MA) is related to poor muscle function. However, this potential objective and clinical tool is not yet implemented in geriatric setting during hospitalization. Our study aimed at: 1) comparing MA, muscle mass and strength measurements in hospitalized older adults with different functional levels, 2) evaluating the association between these measurements.
METHODS: Forty-four hospitalized older adults were divided in 2 groups: 21 Pre-Disabled (PDis (SPPBscore: 6-9): 81 ± 7 years old, SPPBscore:7.6 ± 1.1) and 23 Disabled (Dis (SPPBscore:<6): 83 ± 7 years old, SPPBscore:3.6 ± 1.6). SPPB, body mass (BM) and composition (bio-impedance), handgrip strength (HS, dynamometer) and MA (Pennation angle (PA), muscle thickness (MT); ultrasound) were evaluated.
RESULTS: Relative muscle strength (HS/BM: 0.28 ± 0.08 vs 0.34 ± 0.09 kg/kg), PA (10.6 ± 1.8 vs 12.3 ± 1.9°), and MT (16.4 ± 0.4 vs 19.2 0.4 mm) but not lean body mass were significantly different between Dis and PDis, respectively. Significant associations between PA and the SPPBscore (r2 = 0.37) or walking speed (r2 = 0.38); between SCF and walking speed (r2 = -0.36); as well as between MT and SPPBscore (r2 = 0.29), walking speed (r2 = 0.30), LBM (r2 = 0.382) or MMI (r2 = 0.361) were observed.
CONCLUSION: Muscle architecture (proxy of muscle quality) and functional capacities/status of hospitalized older adults are related. Thus, ultrasound seems to be a potential useful and objective screening tool for clinicians to assess/prevent physical decline during hospitalization. Larger and/or longitudinal studies are needed to confirm our findings from a pilot pragmatic study.