Mobility limitations related to reduced pulmonary function among aging people with chronic obstructive pulmonary disease.

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a major cause of disability. We aimed to analyse the impact of reduced pulmonary function on non-respiratory impairments and mobility activity limitations in an elderly population with COPD and to elucidate which specific limitations on mobility are related to reduced pulmonary function.

METHODS

Cross-sectional study of 110 patients with COPD, recruited from public and university hospital. The effect of impaired pulmonary function on the risk of non-respiratory impairments and mobility limitations was analysed using validated measures, including: the 6-Minute Walk Test (6MWT), skeletal muscle strength, the Short Physical Performance Battery (SPPB), and self-reported mobility questionnaire. Multivariate analysis was used to control for confounders such as age, sex, height, education, and cigarette smoking.

RESULTS

Greater impairment of pulmonary function was associated with less distance walked during the 6MWT, poorer SPPB scores, and greater risk of self-reported mobility limitations (p<0.05). Lower forced expiratory volume in 1 s was also associated with a greater risk of limitations in carrying items under 10 pounds (4.54 kg), walking alone up and down a flight of stairs, and walking two or three neighbourhood blocks. There was no clear statistical relationship between pulmonary function impairment and skeletal muscle strength.

CONCLUSIONS

Impaired pulmonary function was associated with the 6MWT score and limitations on performance-based and self-reported mobility activities, but not with skeletal muscle strength among elderly COPD patients.