Predicting Walking Capacity Outcomes After Moderate-to-High Intensity Locomotor Training in Chronic Stroke.

Moderate-to-high intensity locomotor training (M-HIT) is strongly recommended in stroke rehabilitation, but outcomes are variable. This study aimed to identify baseline clinical characteristics that predict changes in walking capacity following M-HIT in chronic stroke. This analysis used data from the HIT-Stroke Trial (N = 55), which involved up to 36 sessions of either moderate- or high-intensity locomotor training. A prespecified model assessed how well baseline motor impairment (Fugl-Meyer lower limb motor scale [FM-LL]), comfortable gait speed (CGS), and balance confidence (Activities-specific balance confidence scale [ABC]) independently explain changes in 6-minute walk distance (∆6MWD), while controlling for the treatment group. Exploratory analysis tested additional baseline covariates using the all-possible regressions procedure. The predictive value of each potential covariate was assessed by its average contribution to the explained variance in ∆6MWD (∆pseudo-R2). With the prespecified model, 8-week ∆6MWD was significantly associated with baseline FM-LL (β = 5.0 [95% CI: 1.4, 8.6]) and ABC (β = 0.7 [0.0, 1.4]), but not CGS (β = - 44.6 [-104.7, 15.6]). The exploratory analysis revealed that the top 7 covariates with the highest mean ∆pseudo-R2 were FM-LL, pain-limited walking duration, ABC, the use of an assistive device, fatigue, depression, and recent walking exercise history >2 days per week. On average, participants with less motor impairment and higher balance confidence exhibit greater walking capacity improvements after M-HIT in chronic stroke. Additional negative predictive factors may include pain-limited walking duration, use of an assistive device, fatigue, depression, and recent walking exercise; however, these exploratory findings need to be confirmed in future studies. Supplemental Digital Content available at [http://links.lww.com/JNPT/A533].