Functional Mobility and Dyspnoea as Independent Determinants of Sarcopenia Risk: A Shift from Age-Centred to Functional-Centred Assessment in Older Adults

Introduction: Sarcopenia has been defined as a condition related to aging that involves the gradual loss of muscle mass and strength. However, this view may overlook the role of functional impairment and systemic symptoms in older adults. It is important to identify independent and modifiable factors that affect the risk of sarcopenia to create effective prevention strategies. This study aims to explore whether the risk of sarcopenia is linked to demographic, functional, psychosocial, respiratory, and contextual factors, and to determine the most relevant predictors among older adults living in the community and those in institutions. Methods: We conducted a cross-sectional study involving 218 older adults (69% women; average age 75.36±11.64 years), including participants from both community settings and institutions. We assessed sarcopenia risk using the SARC-F questionnaire. Due to the non-normal distribution of the results, we used Spearman correlations to evaluate associations. We included variables that showed significant links to sarcopenia risk in a multivariable binary logistic regression model, which comprised age, self-efficacy for exercise, Timed Up and Go (TUG), dyspnoea severity, and residential status. Results: Higher SARC-F scores were linked with older age (ρ=0.548, p<0.001), lower self-efficacy for exercise (ρ=-0.341, p<0.001), greater dyspnoea severity (ρ=0.412, p<0.001), and worse functional mobility, especially in TUG performance (ρ=0.834, p<0.001). In multivariable analysis, only TUG performance (OR=1.401, p<0.001) and dyspnoea severity (OR=2.887, p=0.004) were independently associated with sarcopenia risk. Age, self-efficacy, and residential status did not significantly predict sarcopenia risk. Conclusions: These findings challenge the age-centred view of sarcopenia and highlight functional mobility impairment and dyspnoea as the main independent factors affecting risk. A focus on functional and symptom-related aspects may help with early identification and prevention. Strategies that target mobility issues and dyspnoea, such as physiotherapy-led exercise programs, could help maintain independence and prevent the progression of sarcopenia in older adults.