Abstract

Introduction: It is unclear what combinations of physical capability markers used to define sarcopenia have the strongest associations with health outcomes. Aim: To compare the associations between different combinations of physical capability markers of sarcopenia with cardiovascular and respiratory outcomes and all-cause mortality. Study design: 469,830 UK Biobank participants were included in this prospective study. Four groups were derived based on combinations of three physical capability markers used to define sarcopenia or severe sarcopenia: gait speed, grip strength and muscle mass. Outcomes studied were all-cause mortality, as well as incidence and mortality from cardiovascular disease (CVD), respiratory disease and chronic obstructive pulmonary disease (COPD). Results: All combinations of physical capability markers used to define sarcopenia or severe sarcopenia identified individuals at increased risk of respiratory disease and all-cause mortality. However, the definition most strongly associated with a wide range of adverse health outcomes was the combination of slow gait speed plus low muscle mass, followed by severe sarcopenia, and the combination of slow gait speed plus low grip strength. The current definition of sarcopenia (low grip strength plus low muscle mass) had the weakest associations with all-cause (HR: 1.35 [95% CI: 1.07 to 1.71]) and respiratory mortality (HR: 1.88 [95% CI: 1.15 to 3.10]), as well as respiratory disease (HR: 1.38 [95% CI: 1.11 to 1.73]) and COPD incidence (HR: 2.08 [95% CI: 1.14 to 3.79]). Conclusions: Associations of sarcopenia with adverse outcomes were strongest when sarcopenia was defined as slow gait speed plus low muscle mass, followed by severe sarcopenia, suggesting that this combination of physical capability markers should be still considered in the diagnosis of sarcopenia.