Frailty and Mobility.

Frailty represents a state of heightened vulnerability. Mobility impairment contributes to the construct of frailty and channels adverse events. While mobility disorder is universal at a high burden of frailty, neither mobility nor balance dysfunction is sufficient to fully define frailty. Frailty represents proximity to complex system failure, with higher-order disturbance, such as mobility and balance disturbance, as a consequence. Impairment of mobility and balance is a common manifestation of illness in the frail individual and is therefore a sensitive marker of acute disease, putatively also in delirium. Clinical measurement of mobility and balance should be prioritized. Consequently, assessment tools, such as the de Morton Mobility Index and the Hierarchical Assessment of Balance and Mobility, are being explored, with the sensitivity of the latter illustrated in the acute hospital setting. Walking with speed and under dual/multi-task conditions better differentiates healthier and frail ambulant adults, providing a basis for screening older adults for pre-emptive interventions. Specific mobility and balance interventions reduce falls risk. However, patients with dementia walk too fast for their level of frailty, creating an ethical dimension to rehabilitation and risk. Overall, there is no need for reduced mobility to reinforce the frailty stereotype; both are potentially modifiable and amenable to intervention strategies.