Clinical Assessment of Walking Capacity in People With Parkinson Disease: Are 2 Minutes Sufficient?

Walking capacity progressively declines in people with Parkinson disease (PD), and assessment of walking is imperative for monitoring disease progression and evaluating intervention efficacy. The main aim of this study was to explore whether the 2-minute walk test (2MWT) could be substituted for the 6-minute walk test (6MWT) as a measure of walking capacity in people with PD. We also sought to investigate construct and known-groups validity of the 2MWT.

A cross-sectional analysis based on data from the Supported Home Training in Everyday Life for Parkinson Disease trial was conducted in a hospital setting. Sixty-three people with idiopathic, mild to moderate PD (29 women; mean age = 69.2 years) were included. Spatiotemporal gait parameters during the 2MWT and the 6MWT were captured by wearable sensors. Linear regression was used to analyze the association between distances walked, whereas paired-samples t tests and repeated-measures analysis of variance were used to explore mean differences in gait parameters.

Distance walked over the 2MWT was very strongly associated with the 6MWT. Gait speed was higher during the shorter test, and several speed-related parameters significantly differed between the tests. There was a trend over the 6MWT, whereby participants performed better during the last 2 minutes of the test. Analyses revealed convergent, discriminant, and known-groups validity of the 2MWT.

These findings suggest that the 2MWT adequately captures walking capacity among people with mild to moderate PD and demonstrates robust convergent validity and ability to discriminate between people at different levels of disease severity.

The 2MWT is a sufficient and valid alternative for physical therapists who wish to assess walking capacity in people with mild to moderate PD.