Impaired arm activity in COPD: a questionable goal for rehabilitation.

Abstract

The most common extrapulmonary problems in chronic obstructive pulmonary disease (COPD) patients are cardiovascular comorbidities, muscle weakness and dysfunction [1–3]. Indeed, the reduced peripheral muscle mass and strength increase patient’s symptoms during effort (fatigue and or dyspnoea) and progressively lead to disability. Furthermore, both lower and upper limb dysfunction has been shown to independently predict the long-term prognosis of COPD patients [2]. The use of arms is involved in many daily domestic tasks and activities. To date, it has been shown that daily arm activities needing elevation above the shoulders may interfere with regular breathing and are associated with dynamic hyperinflation in COPD patients [4]. The research by Meijer et al. [5], published in this issue of the European Respiratory Journal , investigated whether, and in which proportion of muscle effort, arm activities during daily life are different in COPD patients compared with matched healthy individuals. Notably, this study is the first to characterise arm activities associated with daily living in the COPD population. Daily arm and leg domestic activities were measured by accelerometers in moderate-to-severe COPD patients and controls. After correcting for the daily walking time, the time spent on arm activities was similar in COPD patients and healthy controls, whereas the intensity of these activities was lower in COPD patients. In addition, the authors assessed the relative effort of the trapezius, deltoid and biceps muscles using electromyography during 12 standard domestic activities involving upper limbs in both populations. COPD patients performed seven arm activities at a lower intensity compared to control subjects, while the degree of arm elevation was similar. Moreover, in COPD patients compared with controls, muscle effort was found to be performed …