Impact of changes in skeletal muscle mass and quality during the waiting time on outcomes of lung transplantation

Abstract

Introduction: The association of changes in skeletal muscle mass and quality during the waiting time with outcomes of lung transplantation (LT) remains unclear. We aimed to examine the association of changes in skeletal muscle mass and quality during the waiting time, as well as preoperative skeletal muscle mass and quality, with outcomes of LT.

Methods: This study included individuals who underwent LT from brain-dead donors. Skeletal muscle mass (cm² /m² ) and quality (mean Hounsfield units [HU]) of the erector spinae muscle at the 12th thoracic level were evaluated using computed tomography. Preoperative skeletal muscle mass and quality, and their changes during the waiting time were calculated. We evaluated the associations among mechanical ventilation (MV) duration, intensive care unit (ICU) length of stay (LOS), hospital LOS, 6-minute walk distance at discharge, and 5-year survival after LT.

Results: This study included 98 patients. The median waiting time was 594.5 days (interquartile range [IQR], 355.0-913.0). The median changes in skeletal muscle mass and quality were -4.4% (IQR, -13.3-3.1) and -2.9% (IQR, -16.0-4.1), respectively. Severe low skeletal muscle mass at LT was associated with prolonged ICU LOS (B = 8.46, 95% confidence interval [CI]: .51-16.42) and hospital LOS (B = 36.00, 95% CI: 3.23-68.78). Pronounced decrease in skeletal muscle mass during the waiting time was associated with prolonged MV duration (B = 7.85, 95% CI: .89-14.81) and ICU LOS (B = 7.97, 95% CI: .83-15.10).

Conclusion: Maintaining or increasing skeletal muscle mass during the waiting time would be beneficial to improve the short-term outcomes of LT.

Keywords: computed tomography; lung transplantation; prognosis; skeletal muscle; waiting time.