Prognostic value of muscle atrophy in cirrhosis using psoas muscle thickness on computed tomography

Waiting-list mortality in patients with cirrhosis and a relatively low MELD score is a matter of concern. The aim of this study was to determine whether a marker of muscle waste could improve prognostication.

A pre-MELD cohort (waiting time-based allocation; n=186) and a MELD-era cohort (n=376) were examined. At evaluation, transversal psoas muscle thickness (TPMT) was measured on a computed tomography (CT) image at the level of the umbilicus. In the pre-MELD cohort, TPMT/height (mm/m) and the MELD score were entered in univariate and multivariate models to predict mortality after registration. Applicability of pre-MELD findings was tested in the MELD-era.

In the pre-MELD cohort, the MELD score and TPMT/height were significantly associated with mortality. The discrimination of a score combining MELD and TPMT/height (MELD-psoas) was 0.84 (95% CI, 0.62-0.95). In the MELD-era, TPTM/height was significantly associated with mortality, independent of the MELD and MELD-Na scores. There was a 15% increase in mortality risk per unit decrease in TPMT/height. The discrimination of MELD-psoas score (0.82; 95% CI, 0.64-0.93) was superior to that of the MELD score and similar to that of the MELD-Na score. In patients with refractory ascites, mortality was significantly higher when TPMT/height was <16.8 mm/m (42% vs. 9%, p=0.02).

TPMP/height on CT at the level of the umbilicus, an objective marker of muscle waste, may be predictive of mortality in cirrhotic patients, independent of the MELD and MELD-Na scores. It may help to better assess the prognosis of patients with refractory ascites.