Improvement of physical activity in chronic obstructive pulmonary disease by pulmonary rehabilitation and pharmacological treatment

Physical activity (PA) is defined as bodily movement produced by skeletal muscles with energy expenditure beyond resting levels. PA is closely related to reduced morbidity and mortality in chronic obstructive pulmonary disease (COPD). Self-report questionnaires are often subject to recall bias, correlating poorly with objectively qualified PA, and do not provide an accurate estimate of free-living energy expenditure. PA may be objectively evaluated by newly developed tri-axial accelerometers by quantifying steps or body movements over a period of time. Low-intensity, home-based pulmonary rehabilitation (PR) using pedometer feedback improves PA. Improvement in physiological factors correlates with increased walking time in stable elderly COPD patients. This review focuses on the effects of PR and pharmacological treatment on PA in COPD patients. We selected 32 studies from our literature search evaluating the effects of PR and 11 studies examining the effects of pharmacological treatment on PA. Findings in both categories were inconsistent. Nineteen studies showed a positive effect with PR whereas 13 showed no effect. Eight studies showed a positive effect, while three revealed no effect from pharmacological intervention. As both interventions increase exercise capacity without a consistent effect on PA, counseling with behavioral changes may be necessary to achieve a significant and lasting increase in PA. Changing PA behavior in COPD patients requires an interdisciplinary approach involving specialists in respiratory medicine, rehabilitation, social, and behavioral sciences. Future research in this area is warranted to advance our knowledge in this area, specifically with regard to the interaction of pharmacological and non-pharmacological interventions.