Abstract
Background: Endobronchial valve (EBV) insertion for severe emphysema allows to reduce hyperinflation and alleviates respiratory symptoms in patients with chronic obstructive pulmonary disease (COPD). However, few studies investigate their effect on extra-pulmonary manifestations of emphysema. We sought to assess the effect of EBV insertion on skeletal muscle mass and function, as well as determine if skeletal muscle parameters could represent a prognosis factor for response to EBV insertion.
Methods: We conducted a monocentric prospective study including 19 patients. Exhaustive evaluation of lung & skeletal muscle parameters was performed at baseline and 3 and 6 months after EBV insertion. Evaluation included assessment of COPD severity (CAT-score, mMRC, pulmonary function tests, 6-minutes walking test (6MWT)), assessment of body composition with bioimpedance analysis, of thoracic muscles surface and density on CT-scans, and of upper limb force with handgrip test.
Results: EBV insertion led to a significant improvement of lung function after 3 months, that persisted 6 months after the procedure, with a significant decrease in target love volume, residual volume, total lung capacity and a significant increase in forced expiratory volume at 1 second (FEV1). Respiratory symptoms were also alleviated with a significant decrease in mMRC. In contrast, no improvement was observed in skeletal muscle parameters, whether whole-body muscle mass (appendicular skeletal muscle index), thoracic muscles surface or density, or muscle force. Besides, no muscle-related parameter was found to predict response to EBV insertion.
Conclusions: These results strongly advocate for a more thorough referral to pulmonary rehabilitation after the procedure, as well as emphasize the need to find bottom-up drug strategies for COPD-associated sarcopenia.