Inflammatory sarcopenia, a novel concept in chronic liver disease: insights from magnetic resonance imaging biomarkers.

Background: Sarcopenia is an important prognostic factor for chronic liver disease (CLD), and systemic inflammation, which contributes to sarcopenia, is also a potent exacerbator of cirrhosis. This study introduces the novel concept of inflammatory sarcopenia (I-SP) and clarifies its clinical profile.

Methods: This single-center retrospective study included 762 CLD patients with liver stiffness (LS) measured by magnetic resonance elastography (MRE). I-SP was defined as patients with C-reactive protein (CRP) ≥0.5 mg/dL and low muscle mass assessed by magnetic resonance imaging (MRI), compared with non-sarcopenia (non-SP) and non-I-SP (NI-SP). Prognostic analysis for advanced CLD (ACLD) was conducted using a Cox proportional hazards model, with ACLD defined as LS ≥3 kPa.

Results: In CLD, 534, 168, and 60 patients had non-SP, NI-SP, and I-SP, respectively. I-SP patients had a higher complication rate of hepatocellular carcinoma (HCC), which correlated with increased LS and worsening albumin-bilirubin (ALBI) scores (P<0.01 for each). Multivariate logistic regression identified LS (≥3 kPa), ALBI score, alcohol-related liver disease (ALD), and HCC as associated with I-SP (P<0.05 for each). In the follow-up of NI-SP patients (median 36 months), 13% progressed to I-SP and none of the patients had LS <3 kPa. In the ACLD study (n=306), patient survival was stratified into non-SP, NI-SP, and I-SP groups [hazard ratio (HR) reference, 3.4, 15.0, P<0.01 for each]. Multivariate analysis identified ALBI score, HCC, and I-SP as independent prognostic factors (P<0.05 for each).

Conclusions: Our study provides a novel perspective on sarcopenia in CLD and advocates a two-step treatment strategy focused on preventing sarcopenia in ACLD and controlling its progression to I-SP.