Article

OBJECTIVE: To determine the validity of the 6-minute walk test (6MWT) as an
outcome measure to evaluate walking capacity in ambulatory patients with
amyotrophic lateral sclerosis (ALS). DESIGN: Observational study. SETTING:
Multidisciplinary ALS clinic at an academic medical center. PARTICIPANTS:
Patients with ALS (N=186) who ambulate without (stage I) or with (stage II) an
assistive device. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Walking
distance obtained from the 6MWT. RESULTS: Participants performed the 6MWT,
25-foot walk test (25FWT), Timed Up and Go (TUG) test, lower extremity maximum
voluntary isometric contraction (MVIC), ALS Functional Rating Scale-Revised
(ALSFRS-R), and forced vital capacity (FVC). Walking capacity was reduced to 66%
predicted of healthy subjects (75.2%+/-22% in stage I; 42.6%+/-22% in stage II).
The 6MWT correlated with all other outcome measures in ambulatory patients with
ALS (25FWT: r=-.74, P</=.0001; TUG test: r=-.80, P</=.0001; MVIC: r=.64,
P</=.0001; percent predicted FVC: r=.25, P</=.0007; ALSFRS-R: r=.52, P</=.0001;
ALSFRS-R gross motor subscore: r=.71, P</=.0001). When ambulatory patients with
ALS were stratified by stage of ambulation, the 6MWT was associated with all
other outcome measures in stage I (25FWT: r=-.56, P</=.0001; TUG test: r=-.66,
P</=.0001; MVIC: r=.51, P</=.0001; percent predicted FVC: r=.40, P</=.02;
ALSFRS-R: r=.52, P</=.0001; ALSFRS-R gross motor subscore: r=.61, P</=.0001). In
stage II, the 6MWT correlated with the 25FWT (r=-.83, P</=.0001), TUG test
(r=-.77, P</=.0001), MVIC (r=.47, P</=.0001), and ALSFRS gross motor subscore
(r=.61, P</=.0001), but not with percent predicted FVC (r=.09, P</=.513) or
ALSFRS-R (r=.21, P</=.141). CONCLUSIONS: The 6MWT is a valid measure of walking
capacity of ambulatory patients with ALS that is associated with measures of
lower extremity muscle strength and function in both stages of ambulation. The
discordance between the 6MWT with the ALSFRS-R and percent predicted FVC in stage
II ambulatory patients with ALS indicates that the 6MWT is an independent measure
of ambulatory function in both stages of ambulation. The 6MWT may provide a
quantitative, simple, and inexpensive outcome measure of walking capacity for
early stage clinical trials in ambulatory patients with ALS.
CI - Copyright (c) 2017 American Congress of Rehabilitation Medicine. Published by
Elsevier Inc. All rights reserved.

Langue : ANGLAIS