Postural balance in chronic obstructive pulmonary disease during an acute exacerbation: A comparison with stable participants and healthy controls

Abstract

Background: Impaired balance is evident in people with chronic obstructive pulmonary disease (COPD) compared to the healthy elderly, and specific balance components may be further affected during an acute exacerbation (AECOPD). Aims: To evaluate balance performance during an AECOPD compared to stable COPD and controls; to identify possible associations between balance measures, dyspnoea, and muscle strength. Methods: Twenty-six hospitalised patients with AECOPD (FEV 1 , 48±11 %pred) were evaluated prior to discharge using clinical balance tests and centre of pressure analyses, using the Nintendo Wii® balance board. Results were compared to 41 participants with stable COPD (FEV 1 , 45±16 %pred) and 25 matched healthy controls. Dyspnoea was assessed using the Medical Research Council scale and quadriceps strength measured by hand-held dynamometry. Mixed model analysis, paired t-test and regression were used. Results: Patients with AECOPD presented an impaired performance on anteroposterior displacement of centre of pressure (dAP) on both flat (3.9±1.2 vs 3.3±1.0 vs 2.8±0.6, p≤.01) and foam surfaces (7.0±2.2 vs 5.9±1.7 vs 4.6v1.2, p≤.02), compared with both stable and healthy elderly groups. Increased dyspnoea score and lower quadriceps strength were independently associated with a larger dAP amplitude (p<.03), and explained 40% of dAP variance during AECOPD. Conclusion: Patients with AECOPD have poorer balance, especially in the forward/backward direction compared with stable COPD and healthy controls; increased dyspnoea and lower muscle strength were associated with the poorer balance performance.