Sarcopenia of the Psoas Muscles Is Associated With Poor Outcomes Following Lung Transplantation

Abstract

Sarcopenia, a known component of frailty, defined by diminished cross-sectional area of thepsoas muscles, is associated with poor outcomes after arange of surgical procedures. However, little is known of the relationship between sarcopenia of the psoas muscles (SPM) and long-term survival, decline in pulmonary function, and graft failure after lung transplantation. We reviewed patients who underwent primary lung transplantation at our institution from 2011 to 2014. Cross-sectional areas of the psoas muscles at the L4 vertebral level were measured using preoperative computed tomography. Gender-based cutoff values for sarcopenia were generated and validated. The primary outcomes were 1-, 2-, and 3-year all-cause mortality, forced expiratory volume in 1 second values, and graft function. Adjusted logistic regression and survival analysis was used to analyze outcomes. Ninety-five patients were included in this study; 39 (41.1%) patients were considered sarcopenic. SPM was significantly associated with short-term and midterm mortality on multivariate analysis (1 year: odds ratio [OR], 8.7, p= 0.017; 2 years: OR, 12.7, p < 0.01; 3years: OR, 13.4, p < 0.01). Survival analysis showed significantly decreased survival in sarcopenic patients at 3years (35.9% versus 76.8%; p < 0.01). SPM is also associated with decreased forced expiratory volume in 1second (coefficient, -17.3; p= 0.03). Adjusted Cox analysis showed an increased hazard for all-cause mortality (hazard ratio, 5.8, p < 0.01) and graft failure (hazard ratio, 14.7, p < 0.01) in sarcopenic patients. This study demonstrates a significant association between SPM and death, pulmonary function, and graft failure in patients receiving a lung transplant. Determining SPM preoperatively may be a useful component of frailty assessment and a predictor of survival in this patient population.