Relationship between clinical impact of the disease and postural balance in COPD patients

Abstract

COPD patients have postural balance impairments but its relation with clinical impact remains unknown. Aim: To identify the relationship between clinical disease impact and postural balance in COPD patients. Methods: 68 patients were assessed for COPD assessment test (CAT) and postural balance by centre of pressure displacement analysis using a portable device in 3 conditions: standing with eyes open (EO), eyes closed (EC) and on a foam surface with open eyes. Outcomes for postural balance included amplitude (amp) (degree of movement to maintain balance) and path velocity (vel) in anteroposterior (AP) and mediolateral (ML) directions. Patients were divided according to CAT: low (n=9; 68±7yrs; FEV1 40±11%pred), medium (n=36; 69±10yrs; FEV1 43±16%pred) and high/very high impact (n=23; 64±9yrs; FEV1 42±13%pred). Kruskal-Wallis and Dunn9s tests were used to compare groups. Results: Groups were similar in age and severity of disease. Patients with high/very high clinical impact presented greater variation in the APamp with EO (2.5±1.0, 1.8±0.4, 2.0±0.8cm;p=0.02) and in the MLamp with EC (1.9±1.6, 1.0±0.4, 1.3±0.7cm;p=0.01) compared to low but not to medium, respectively. APvel (1.5±0.6, 1.2±0.5, 1.2±0.3cm;p=0.03) and MLvel (0.7±0.3, 0.5±0.2, 0.5±0.1cm;p=0.01) with EC presented greater variation in the high/very high compared to medium but not to low, respectively. APamp with EC (3.4±1.2, 2.3±0.4, 2.7±1.3cm;p<0.01) presented greater variation in the high/very high compared to low and medium, respectively. There was no difference on foam surface. Conclusion: Our results suggest that patients with worse clinical impact of the disease have poorer AP and ML balance. This has implications for practice.