Nonalcoholic Steatohepatitis, Sarcopenia, and Liver Transplantation

Abstract

Nonalcoholic fatty liver disease (NAFLD) is a spectrum ranging from simple steatosis to nonalcoholic steatohepatitis (NASH). NASH is associated with progression to cirrhosis and an increased risk for liver-related mortality. 1 Sarcopenia, defined as low muscle mass (MM) and function, occurs in 40% to 60% of patients with cirrhosis and 20% of patients with NASH. 2 There is significant overlap and synergism between NASH and sarcopenia, with increased risk for poor outcomes when both are present. 1 Herein we review the complex interplay between NASH and sarcopenia, and the impact on outcomes in relation to liver transplantation (LT). Sarcopenia increases the risk for NAFLD (odds ratio [OR], 1.3) 1,3 independent of age, obesity, insulin resistance (IR), or metabolic syndrome (MS). 1 Patients with sarcopenia also have a higher prevalence of NASH (OR, 2.4) in comparison with their counterparts with normal MM 3 (Fig. 1). Both MM (OR, 2.6) and muscle function (OR, 1.5) correlate with NAFLD, with patients with sarcopenia having the highest odds of development of NAFLD (OR, 3.9). 4 Changes in muscle quality (reflecting function) may precede changes in MM. 4 Myosteatosis (fat infiltration of muscle) was seen in up to 60% of patients with NASH and is associated with increased mortality in patients with cirrhosis. 2

De Novo Metabolic Syndrome 1 Year after Liver Transplantation and Its Association with Mid- and Long-Term Morbidity and Mortality in Liver Recipients

“…Instead, it often persists and likely worsens in the long-term observation [ 41 ]. Furthermore, MASH and sarcopenia are uniquely intermeshed [ 42 ]. Both entities have been evidenced to share many pathophysiological pathways leading to increased insulin resistance and inflammation [ 39 , 42 ].…”

“…Furthermore, MASH and sarcopenia are uniquely intermeshed [ 42 ]. Both entities have been evidenced to share many pathophysiological pathways leading to increased insulin resistance and inflammation [ 39 , 42 ]. Accordingly, their coexistence produces unfavourable synergistic effects [ 42 ].…”

“…Both entities have been evidenced to share many pathophysiological pathways leading to increased insulin resistance and inflammation [ 39 , 42 ]. Accordingly, their coexistence produces unfavourable synergistic effects [ 42 ]. Finally, frailty reportedly affects approximately 50% of patients with end-stage liver disease due to underlying MASH, which considerably exceeds projections for their non-MASH peers [ 43 ].…”