Short step length mainly contributes to slow gait speed in elderly patients with COPD

Abstract

Background: Slow gait speed (GS) is well recognized in elderly COPD. However which parameter of gait contributes to GS has been uncertain. We aimed to investigate the determinants of GS among gait parameters, and the relationships between the gait parameters and clinical characteristics in elderly COPD. Methods: Twenty-three outpatients with COPD (age, 71±7years, FEV 1 , 53±23%pred) and 13 healthy controls (age, 72±6 years) performed 10-m gait test at their usual pace wearing a tri-axial accelerometer on their low back. Step time (Step-T), step length (Step-L), GS, and Step-T standard deviation were estimated as the gait parameters. FEV 1 , MMRC scores, 6-min walk distance, quadriceps strength, one-legged stance time, and daily steps were evaluated as the clinical characteristics of COPD. The between-group differences in the gait parameters were analyzed. Correlation analysis and stepwise multivariate regression analysis were conducted among the gait parameters to clarify the determinants of GS in the COPD group. Correlations of each gait parameter to the clinical characteristics were determined in the COPD group. Results: Significant reductions in all gait parameters were observed in COPD (all p Conclusions: Short Step-L mainly contributed to slow GS among three gait parameters. Step-L were significantly correlated with all clinical characteristics. These results suggest that an approach to Step-L may improve GS in elderly COPD.