Muscle Mass, Strength, Power and Physical Performance and Their Association with Quality of Life in Older Adults, the Study of Muscle, Mobility and Aging (SOMMA)

Background: Sarcopenia negatively impacts quality of life. It is unclear whether different measures of muscle size, strength, physical performance, and fitness have similar associations with quality of life. Objective: To describe associations of sarcopenia metrics with quality of life outcomes. Participants: Community-dwelling adults aged 70+ years participating in the SOMMA (Study of Muscle, Mobility and Aging) study, (N=875 ((women: 519, men:356)), age, years 76.3 +/- 5.0). Design and Settings: Two academic medical centers. Measurements: Measures included muscle size (MRI- muscle volume. D3Cr muscle mass); strength and power (grip strength, leg extension power and strength, stair climb); walking and physical performance (4m and 400m walk, SPPB (Short Physical Performance Battery), chair stand); fitness (VO2 peak); health related quality of life (EQ-5D); and anthropometrics (weight, height, and body mass index). Results were stratified by sex. Correlations, scatterplots and linear regression models described the association between various measures of sarcopenia and fitness with overall quality of life score (EQ 5D VAS) as a continuous variable. We also quantified differences between sarcopenia and fitness measures by overall QOL (Quality of Life) as a categorical variable (low, medium, high) and by QOL subcomponents (pain and discomfort, problems with usual activities, mobility, anxiety and depression, and problems with self-care) using distributionally appropriate methods. Results: Walking tests and physical performance were most consistently (but modestly) associated with overall quality of life (r similar to 0.2, p<.001) and its subcomponents. For both men and women, several sarcopenia and fitness measures were more strongly associated with pain and usual activity than other QOL components. Conclusions: Poor performance, lower fitness and lower strength are related to worse quality of life, particularly pain, in older adults. Future studies should quantify these relationships longitudinally.