The Functional Independence of Patients With Stroke Sequelae: How Important Is the Speed, Oxygen Consumption, and Energy Cost of Walking?

Abstract

To evaluate the association between self-selected walking speed (S_free), oxygen consumption at S_free (Vo_2free), the oxygen cost of walking (Cw) at S_free, and mobility independence and independence for activities of daily living in individuals poststroke. Cross-sectional study. Hospital. Individuals with stroke who were able to walk without human assistance were included. We included 90 individuals (N=90; mean age, 63.5±14.0y). Not applicable. Cw was captured during walking from measurements of S_free and Vo_2free. We assessed mobility independence based on the modified Functional Ambulation Classification (mFAC) and independence in activities of daily living by the Barthel Index (BI). Multiple linear regression analyses were performed to evaluate the independence of Cw, Vo_2free, and S_free from the determination of BI and mFAC among the various characteristics of the population (age, stroke delay, body mass index, motor function, spasticity). We reported Cw=0.36 mL/kg/m (interquartile range [IQR]=0.28 mL/kg/m), S_free=0.60±0.32 m/s, Vo_2free=11.2 mL/kg/min (IQR=1.8 mL/kg/min). The multiple linear regression analyses showed that Cw and S_free were independently associated with the BI (P<.01) and the mFAC (P<.01) scores. Vo_2free was not found to be an explanatory variable of functional independence (P>.05). Cw was independently associated with functional independence. This association appears to be primarily determined by S_free and not Vo_2free, underscoring the importance of evaluating and acting on S_free to improve the functional independence of individuals with stroke.