Low gait speed is better than frailty and sarcopenia at identifying the risk of disability in older adults

Objective To compare frailty, sarcopenia and their respective components to determine which is more effective in identifying the risk of disability in basic and instrumental activities of daily living (BADL and IADL, respectively). Methods A longitudinal study involving 3,637 individuals without disabilities concerning BADL and 3,696 individuals without disabilities regarding IADL at baseline. Frailty was defined using the phenotype. Sarcopenia was determined according to the criteria proposed by the EWGSOP2: low strength (grip strength <27 kg for men and <16 kg for women), low skeletal muscle mass index (<9.36 kg/m2 for men and <6.73 kg/m2 for women) and low physical performance (gait speed ≤0.8 m/s). In addition to the complete constructs, each component was assessed. Poisson mixed models were utilised, with the outcome identified as incident cases of disability over 8 years, adjusted for covariates. Results: Pre-frailty was associated with a 17% and 18% annual increase in the risk of disability for BADL and IADL, respectively. These figures were 27% and 28% for individuals classified as frail. Sarcopenia was not associated with an increased risk of disability. Amongst the components of frailty and sarcopenia, low physical performance, assessed by gait speed ≤0.8 m/s, was the most effective for identifying the risk of disability (12% per year for BADL and 14% per year for IADL). Conclusion In clinical practice, low physical performance (gait speed ≤0.8 m/s) may be the preferred tool for screening the risk of functional decline in older adults.