Supplementary Material for: Effect of endobronchial valve treatment on skeletal muscles, fatigue, and sleep in severe emphysema patients

Introduction
Skeletal muscle dysfunction, fatigue, and poor sleep quality are common in severe emphysema patients. Endobronchial valve (EBV) treatment is a bronchoscopic procedure which improves pulmonary function, quality of life, and exercise capacity in these patients. However, its potential beneficial effects on skeletal muscle function, fatigue and sleep are unclear. Our aim was to investigate the effects of EBV treatment on these outcomes.

Methods
We conducted a prospective cohort study assessing the 2nd parasternal intercostal muscle thickening fraction, and quadriceps muscle thickness and rectus femoris cross-sectional area (RFCSA), both using ultrasound, limb muscle function using the 30-second sit-to-stand test, fatigue with the Checklist Individual Strength (CIS) fatigue subscale (score ≥36 indicating severe fatigue), and sleep quality with the Pittsburgh Sleep Quality Index (PSQI) at baseline and 6 months following EBV treatment.

Results
A total of twenty patients were included. At the six-month follow-up, significant improvements were observed in pulmonary function, quadriceps thickness and RFCSA in the nondominant leg, as well as in limb muscle function. Intercostal thickening fraction did not change following treatment. Fatigue decreased significantly, reducing severe fatigue prevalence from 70% to 25%. Sleep quality was generally poor and remained unchanged.

Conclusions
Our results show that quadriceps muscle size and function, as well as fatigue, significantly improve following EBV treatment in severe emphysema patients. However, BLVR seems to have no impact on intercostal thickening fraction and patient-reported sleep quality. This study highlights the beneficial extrapulmonary effects of EBV treatment in patients with severe emphysema, further supporting its clinical use.