Patients with chronic obstructive pulmonary disease may walk slower and show changes in gait as the disease progresses, according to research based on real-world data from multiple European centers.
In the study, investigators involved 549 patients with chronic obstructive pulmonary disease (COPD) who wore motion sensor devices on their lower backs for 7 consecutive days. The devices measured walking speed, step frequency (cadence), stride length, and variability of walking patterns. The investigators also evaluated data from 19 healthy older adults for comparison.
The COPD group had a mean age of 68 years, 37% of whom were female. The healthy comparison group had a mean age of 71 years, and 47% of them were female. Walking performance was analyzed during both short and long walking bouts.
During longer walking bouts lasting more than 30 seconds, patients with COPD walked at a mean speed of 0.83 m per second compared with 0.90 m per second in healthy adults. Their maximum walking speed during these bouts was 0.99 m per second, while healthy adults reached 1.12 m per second. These differences remained statistically significant after adjusting for age, sex, height, and walking time.
Cadence was also reduced in COPD. During longer walking bouts, maximum cadence reached 100 steps per minute, compared to 107 steps per minute in the healthy group.
Walking ability declined with increasing COPD severity. Among those with mild COPD (GOLD 1 stage), mean walking speed during longer bouts was 0.88 m per second. This decreased to 0.85 m per second for moderate COPD (GOLD 2), 0.80 m per second for severe COPD (GOLD 3), and 0.78 m per second for very severe COPD (GOLD 4). Similar declines were observed in cadence.
The investigators also analyzed bout-to-bout variability, reflecting consistency in walking patterns. Variability in walking speed and cadence was affected by breathlessness severity but not consistently across all COPD stages. Stride duration variability showed no major differences across COPD severity levels or compared with healthy adults.
Participants with COPD walked a median of 6561 steps daily, with a median walking duration of 1.17 hours per day. Their median 6-minute walk distance was 416 m. The study population included 11% with mild COPD, 43% with moderate disease, 32% with severe disease, and 14% with very severe disease.
This study provided a detailed assessment of how COPD could affect real-world walking patterns. Unlike laboratory-based studies, the findings captured walking behavior during participants' normal daily activities. The investigators suggested that walking speed and step frequency may serve as measurable indicators of COPD progression and could inform future interventions targeting mobility in this population.
Full disclosures can be found in the study.
Source: European Respiratory Journal
