The 6-Minute Walk Test predicts long-term physical improvement among intensive care unit survivors: a prospective cohort study

ABSTRACT

Objective:

To evaluate the ability of the 6-Minute Walk Test to predict long-term physical functional status improvement among intensive care unit survivors.

Methods:

Thirty-two intensive care unit survivors were prospectively evaluated from February 2017 to August 2018 in a post-intensive care unit outpatient clinic in Brazil. Individuals with intensive care unit stays > 72 hours (emergency admissions) or > 120 hours (elective admissions) attending the post-intensive care unit clinic four months after intensive care unit discharge were consecutively enrolled. The association between the 6-Minute Walk Test distance at baseline and physical functional status was assessed over 8 months using the Barthel Index.

Results:

The mean 6-Minute Walk Test distance was significantly lower in intensive care unit survivors than in the general population (405m versus 557m; p < 0.001). Age (β = -4.0; p < 0.001) and muscle weakness (β = -99.7; p = 0.02) were associated with the 6-Minute Walk Test distance. A 6-Minute Walk Test distance was associated with improvement in physical functional status over the 8-month follow-up (odds ratio for each 10m of 1.07; 95%CI 1.01 - 1.16; p = 0.03). The area under the Receiver Operating Characteristic curve for the 6-Minute Walk Test prediction of physical functional status improvement was 0.72 (95%CI 0.53 - 0.88).

Conclusion:

The 6-Minute Walk Test performed 4 months after intensive care unit discharge predicted long-term physical functional status among intensive care unit survivors with moderate accuracy.

Keywords:
Intensive care; After care; Rehabilitation; Physical functional performance; Exercise test