BODY COMPOSITION AND MORBIDITY FOLLOWING ORTHOTOPIC LIVER TRANSPLANTATION - THE VALUE OF QUALITY OVER QUANTITY

Background: The significance of preoperative body composition is in the spotlight of interest in various diseases. Here we assessed the role of sarcopenia and myosteatosis as prognostic factors following orthotopic liver transplantation (OLT). Methods: The data of 225 consecutive OLT recipients from a prospective database were analyzed retrospectively (05/2010-01/2018). Computed tomography-based lumbar skeletal muscle index-L3SMI, visceral adipose tissue area-L3VAT and mean muscle attenuation-MA were calculated using a segmentation tool (3DSlicer). Patients with sarcopenia (low L3SMI), visceral obesity (high L3VAT) and myosteatosis (low MA) were identified using predefined sex-specific cutoff values. Parametric- and non-parametric tests as well as uni- and multivariable logistic regression were used to determine the association of body composition profiles with outcome. Results: The cutoff values of myosteatosis resulted in a good stratification of patients into low- and high-risk groups in terms of major morbidity (Clavien-Dindo-CD>=3b). Myosteatotic patients had significantly higher complication (90-days CCI 68±32 vs. 44±30, p<0.0001) and early allograft dysfunction rates. These patients spent significantly longer time at the ICU and in hospital. The estimated costs were 44% higher compared to patient with superior muscle quality. Significant correlation was found between MA and various outcome parameters (ICU, hospital stay, CCI, costs). Cutoff values for the other used body composition parameters failed to identify high risk patients and did not correlate with the perioperative outcome. Multivariable analysis identified myosteatosis as an independent prognostic factor for major morbidity (2.432 OR, 1.319-4.486, p=0.004). Adding myosteatosis to the well-established Balance of Risk-BAR score resulted in the increase of the prognostic value for morbidity compared to the original BAR-score (Area-under-the-curve 0.710 vs 0.677). Conclusion: Our Results indicate the superior predictive value of muscle quality (myosteatosis) over quantity (sarcopenia) in terms of morbidity following OLT. Myosteatosis might be a valuable easy to assess novel parameter in already established outcome prediction tools.