ImportancePhysical biomarkers for stratifying patients with lung cancer into subtypes suggestive of outcomes are underexplored.ObjectiveTo investigate the clinical utility of respiratory sarcopenia for optimizing postoperative risk stratification in patients with non–small cell lung cancer (NSCLC).Design, Setting, and ParticipantsThis retrospective cohort study reviewed consecutive patients undergoing lobectomy and mediastinal lymph node dissection for NSCLC at 2 institutions in Tokyo, Japan, between 2009 and 2018. Eligible patients underwent electronic computed tomography image analysis. Follow-up began at the date of surgery and continued until death, the last contact, or March 2022. Data analysis was performed from April 2022 to March 2023.Main Outcomes and MeasuresRespiratory sarcopenia was identified by poor respiratory strength (peak expiratory flow rate) and was confirmed by a low pectoralis muscle index (PMI; pectoralis muscle area/body mass index). Patients with poor peak expiratory flow rate but normal PMI received a diagnosis of pre–respiratory sarcopenia. Short-term and long-term postoperative outcomes were compared among patients with a normal status, pre–respiratory sarcopenia, and respiratory sarcopenia. Group differences were analyzed using the Kruskal-Wallis test and Pearson χ2 test for continuous and categorical data, respectively. Survival differences were compared using the log-rank test. Univariable and multivariable analyses were conducted using the Cox proportional hazards model.ResultsOf a total of 1016 patients, 806 (497 men [61.7%]; median [IQR] age, 69 [64-76] years) were eligible for electronic computed tomography image analysis. The median (IQR) duration of follow-up for survival was 5.2 (3.6-6.4) years. Respiratory strength was more closely correlated with PMI than pectoralis muscle radiodensity (Pearson r2, 0.58 vs 0.29). Respiratory strength and PMI declined with aging simultaneously (both P for trend < .001). Pre–respiratory sarcopenia was present in 177 patients (22.0%), and respiratory sarcopenia was present in 130 patients (16.1%). The risk of postoperative complications escalated from 82 patients (16.4%) with normal status to 39 patients (22.0%) with pre–respiratory sarcopenia to 39 patients (30.0%) with respiratory sarcopenia (P for trend < .001), as did the risk of delayed recovery after surgery (P for trend < .001). Compared with patients with normal status or pre–respiratory sarcopenia, patients with respiratory sarcopenia exhibited worse 5-year overall survival (438 patients [87.2%] vs 133 patients [72.9%] vs 85 patients [62.5%]; P for trend < .001). Multivariable analysis identified respiratory sarcopenia as a factor independently associated with increased risk of mortality (hazard ratio, 1.83; 95% CI, 1.15-2.89; P = .01) after adjustment for sex, age, smoking status, performance status, chronic heart disease, forced expiratory volume in 1 second, diffusing capacity for carbon monoxide, C-reactive protein, albumin, carcinoembryonic antigen, histology, and pathologic stage.Conclusions and RelevanceThis study identified individuals at higher risk of poor outcomes by screening and staging respiratory sarcopenia. The early diagnosis of respiratory sarcopenia could optimize management strategies and facilitate longitudinal care in patients with NSCLC.

中文翻译：

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非小细胞肺癌术后风险分层的呼吸性肌肉减少症诊断


重要性将肺癌患者分层为提示结果的亚型的物理生物标志物未得到充分探索。目的探讨呼吸性肌肉减少症在优化非小细胞肺癌 （NSCLC） 患者术后风险分层方面的临床效用。设计、设置和参与者这项回顾性队列研究回顾了 2009 年至 2018 年在日本东京的 2 个机构接受肺叶切除术和纵隔淋巴结清扫术的 NSCLC 连续患者。符合条件的患者接受了电子计算机断层扫描图像分析。随访从手术日期开始，一直持续到死亡、最后一次接触或 2022 年 3 月。主要结局和测量呼吸性肌肉减少症由呼吸力量差（呼气峰流速）确定，并通过低胸大肌指数 （PMI;胸大肌面积/体重指数） 证实。呼气峰流速差但 PMI 正常的患者被诊断为呼吸前肌肉减少症。比较正常状态、呼吸前肌肉减少症和呼吸性肌肉减少症患者的短期和长期术后结局。分别使用 Kruskal-Wallis 检验和 Pearson χ2 检验对连续数据和分类数据分析组差异。使用 log-rank 检验比较生存差异。使用 Cox 比例风险模型进行单变量和多变量分析。结果在总共 1016 例患者中，806 例 （497 例男性 [61.7%];中位 [IQR] 年龄，69 [64-76] 岁）符合电子计算机断层扫描图像分析的条件。中位 （IQR） 生存期随访时间为 5.2 （3.6-6.4） 年。 呼吸力量与 PMI 的相关性比胸大肌放射密度更密切 （Pearson r2,0.58 vs 0.29）。呼吸强度和 PMI 同时随着年龄的增长而下降 （趋势 < .001 的 P 均 P）。177 例患者 （22.0%） 出现呼吸前肌肉减少症，130 例患者 （16.1%） 出现呼吸性肌肉减少症。术后并发症的风险从 82 名状态正常的患者 （16.4%） 上升到 39 名呼吸前肌肉减少症患者 （22.0%） 到 39 名呼吸性肌肉减少症患者 （30.0%） （P 趋势 < .001），手术后延迟恢复的风险 （P 趋势 < .001）。与正常状态或呼吸前性肌肉减少症患者相比，呼吸性肌肉减少症患者的 5 年总生存期更差 （438 例患者 [87.2%] 对 133 例患者 [72.9%] 对 85 例患者 [62.5%];P 代表趋势 < .001）。多变量分析发现呼吸性肌肉减少症是与死亡风险增加独立相关的因素（风险比，1.83;95% CI，1.15-2.89;P = .01） 调整性别、年龄、吸烟状况、体能状态、慢性心脏病、1 秒用力呼气量、一氧化碳弥散量、C 反应蛋白、白蛋白、癌胚抗原、组织学和病理分期后。结论和相关性本研究通过筛查和分期呼吸性肌肉减少症确定了不良结局风险较高的个体。呼吸性肌肉减少症的早期诊断可以优化管理策略并促进 NSCLC 患者的纵向护理。