Imaging-based assessment of sarcopenia is a well-validated prognostic tool for patients with chronic liver disease. However, little is known about its value in patients with primary sclerosing cholangitis (PSC). This cross-sectional study aimed to investigate the predictive value of the cross-sectional imaging-based skeletal muscle index (SMI) for transplant-free survival (TFS) in patients with PSC. A total of 95 patients with PSC who underwent abdominal cross-sectional imaging between 2008 and 2022 were included in this retrospective study. SMI was measured at the third lumbar vertebra level (L3-SMI). The cut-off values to define sarcopenia were < 50 cm²/m² in male patients and < 39 cm²/m² in female patients. The primary outcome of this study was TFS, which was defined as survival without liver transplantation or death from any cause. Our study indicates that L3-SMI sarcopenia impairs TFS in patients with PSC (5-year TFS: 33.9% vs. 83.3%, p = 0.001, log-rank test). L3-SMI sarcopenia was independently associated with reduced TFS via multivariate Cox regression analysis (HR = 2.749; p = 0.028). Body mass index reduction > 10% at 12 months, which is used as MELD standard exception (SE) criterion in Eurotransplant (in Germany only until September 2023), was not significantly associated with TFS in the multivariate Cox regression analysis (HR = 1.417; p = 0.330). Substitution of BMI reduction with L3-SMI in the German SE criteria improved the predictive accuracy of TFS compared to the established SE criteria (multivariable Cox regression analysis: HR = 4.007, p < 0.001 vs. HR = 1.691, p = 0.141). Imaging-based diagnosis of sarcopenia via L3-SMI is associated with a low TFS in patients with PSC and may provide additional benefits as a prognostic factor in patient selection for liver transplantation.

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基于影像学的肌少症诊断有助于原发性硬化性胆管炎的无移植生存

基于影像学的肌肉减少症评估是慢性肝病患者经过充分验证的预后工具。然而，人们对其对原发性硬化性胆管炎（PSC）患者的价值知之甚少。本横断面研究旨在探讨基于横断面成像的骨骼肌指数 (SMI) 对 PSC 患者无移植生存 (TFS) 的预测价值。这项回顾性研究纳入了 2008 年至 2022 年间接受腹部横断面成像的 95 名 PSC 患者。 SMI 是在第三腰椎水平 (L3-SMI) 处测量的。定义肌肉减少症的临界值在男性患者中为 < 50 cm2/m2，在女性患者中为 < 39 cm2/m2。这项研究的主要结果是 TFS，其定义为未进行肝移植的存活率或任何原因导致的死亡。我们的研究表明，L3-SMI 肌少症会损害 PSC 患者的 TFS（5 年 TFS：33.9% 对比 83.3%，p = 0.001，对数秩检验）。通过多变量 Cox 回归分析，L3-SMI 肌少症与 TFS 降低独立相关（HR = 2.749；p = 0.028）。 12 个月时体重指数下降 > 10%，在欧洲移植中用作 MELD 标准例外 (SE) 标准（仅在德国直至 2023 年 9 月），在多变量 Cox 回归分析中与 TFS 没有显着相关性（HR = 1.417； p = 0.330）。与既定的 SE 标准相比，在德国 SE 标准中用 L3-SMI 替代 BMI 降低提高了 TFS 的预测准确性（多变量 Cox 回归分析：HR = 4.007，p < 0.001 对比 HR = 1.691，p = 0.141）。通过 L3-SMI 对肌肉减少症进行影像学诊断与 PSC 患者的低 TFS 相关，并且可能作为肝移植患者选择的预后因素提供额外的益处。