ImportancePrior studies demonstrated consistent associations of low skeletal muscle mass assessed on surgical planning scans with postoperative morbidity and mortality. The increasing availability of imaging artificial intelligence enables development of more comprehensive imaging biomarkers to objectively phenotype frailty in surgical patients.ObjectiveTo evaluate the associations of body composition scores derived from multiple skeletal muscle and adipose tissue measurements from automated segmentation of computed tomography (CT) with the Hospital Frailty Risk Score (HFRS) and adverse outcomes after abdominal surgery.Design, Setting, and ParticipantsThis retrospective cohort study used CT imaging and electronic health record data from a random sample of adults who underwent abdominal surgery at 20 medical centers within Kaiser Permanente Northern California from January 1, 2010, to December 31, 2020. Data were analyzed from April 1, 2022, to December 1, 2023.ExposureBody composition derived from automated analysis of multislice abdominal CT scans.Main Outcomes and MeasuresThe primary outcome of the study was all-cause 30-day postdischarge readmission or postoperative mortality. The secondary outcome was 30-day postoperative morbidity among patients undergoing abdominal surgery who were sampled for reporting to the National Surgical Quality Improvement Program.ResultsThe study included 48 444 adults; mean [SD] age at surgery was 61 (17) years, and 51% were female. Using principal component analysis, 3 body composition scores were derived: body size, muscle quantity and quality, and distribution of adiposity. Higher muscle quantity and quality scores were inversely correlated (r = −0.42; 95% CI, −0.43 to −0.41) with the HFRS and associated with a reduced risk of 30-day readmission or mortality (quartile 4 vs quartile 1: relative risk, 0.61; 95% CI, 0.56-0.67) and 30-day postoperative morbidity (quartile 4 vs quartile 1: relative risk, 0.59; 95% CI, 0.52-0.67), independent of sex, age, comorbidities, body mass index, procedure characteristics, and the HFRS. In contrast to the muscle score, scores for body size and greater subcutaneous and intermuscular vs visceral adiposity had inconsistent associations with postsurgical outcomes and were attenuated and only associated with 30-day postoperative morbidity after adjustment for the HFRS.Conclusions and RelevanceIn this study, higher muscle quantity and quality scores were correlated with frailty and associated with 30-day readmission and postoperative mortality and morbidity, whereas body size and adipose tissue distribution scores were not correlated with patient frailty and had inconsistent associations with surgical outcomes. The findings suggest that assessment of muscle quantity and quality on CT can provide an objective measure of patient frailty that would not otherwise be clinically apparent and that may complement existing risk stratification tools to identify patients at high risk of mortality, morbidity, and readmission.

中文翻译：

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身体成分的自动 CT 分析作为腹部手术中虚弱的生物标志物

重要性先前的研究表明，手术计划扫描评估的低骨骼肌质量与术后发病率和死亡率之间存在一致的关联。成像人工智能的日益普及使得能够开发更全面的成像生物标志物，以客观地对手术患者的虚弱表型进行分型。医院虚弱风险评分 (HFRS) 和腹部手术后的不良后果。设计、设置和参与者这项回顾性队列研究使用了 CT 成像和电子健康记录数据，这些数据来自在北加州 Kaiser Permanente 的 20 个医疗中心接受腹部手术的成年人的随机样本2010年1月1日至2020年12月31日。数据分析时间为2022年4月1日至2023年12月1日。暴露来自多层腹部CT扫描自动分析的身体成分。主要结果和措施该研究的主要结果是-导致出院后 30 天再次入院或术后死亡。次要结果是接受腹部手术的患者术后 30 天的发病率，这些患者被抽样向国家手术质量改进计划报告。结果该研究包括 48 444 名成年人；手术时平均 [SD] 年龄为 61 (17) 岁，其中 51% 为女性。通过主成分分析，得出 3 个身体成分评分：身体尺寸、肌肉数量和质量以及肥胖分布。较高的肌肉数量和质量得分呈负相关（r=-0.42； 95% CI，-0.43 至 -0.41）与 HFRS 相关，并与 30 天再入院或死亡率风险降低相关（四分位数 4 与四分位数 1：相对风险，0.61；95% CI，0.56-0.67）和 30 天再入院或死亡风险降低术后发病率（四分位数 4 与四分位数 1：相对风险，0.59；95% CI，0.52-0.67），与性别、年龄、合并症、体重指数、手术特征和 HFRS 无关。与肌肉评分相反，体型评分以及皮下和肌间脂肪与内脏肥胖的评分与术后结果的相关性不一致，并且在调整 HFRS 后减弱，仅与术后 30 天的发病率相关。结论和相关性在本研究中，较高肌肉数量和质量评分与虚弱程度相关，并与 30 天再入院和术后死亡率和发病率相关，而体型和脂肪组织分布评分与患者虚弱程度无关，并且与手术结果的相关性不一致。研究结果表明，CT 上肌肉数量和质量的评估可以提供患者虚弱程度的客观衡量标准，而这种虚弱程度在临床上不会明显表现出来，并且可以补充现有的风险分层工具，以识别死亡、发病和再入院高风险的患者。