The incidence of postoperative frailty is notably high among patients with colorectal cancer. Numerous studies have established a strong association between frailty and adverse outcomes, including postoperative complications and mortality. Given that frailty is a dynamic process, there is a scarcity of research exploring its occurrence and progression in colorectal cancer patients.

To investigate the developmental trajectory of postoperative frailty in patients with colorectal cancer and identify its influencing factors through a longitudinal research approach and to provide a theoretical basis for managing frailty in this population.

We employed a convenience sampling method to select patients with colorectal cancer from Jiangsu Provincial People's Hospital between July and December 2022. Data on general information and relevant factors were collected from the participants. The Tilburg Frailty Scale was utilized to assess frailty at four intervals: preoperatively, and then at 1 month, 3 months, and 6 months post-surgery. The growth mixture model was constructed to delineate the developmental trajectory of postoperative frailty and Logistic regression was used to analyze the factors influencing frailty in colorectal cancer patients.

A total of 374 patients completed the survey. By fitting the frailty data at four time points, results showed three optimal trajectory models: Health Improvement Type (n=305, 81.5%), Frailty Improvement Type (n=25, 6.7%), and Frailty Persistence Type (n=44, 11.8%). For clinical relevance, the latter two types were merged into a "Frailty Heterogeneity Trajectory". Multivariate Logistic regression analysis revealed several influencing factors for the frailty heterogeneity trajectory: age (OR=1.141, 95%CI=1.065-1.223), nutritional score (OR=0.424, 95%CI=0.303-0.594), number of comorbidities (OR=2.884, 95%CI=1.158-7.184), neoadjuvant therapy (OR=29.510, 95%CI=5.511-158.007), stoma establishment (OR=37.313, 95%CI=8.604-161.819), postoperative chemoradiotherapy (OR=95.071, 95%CI=17.664-511.674), depression level (OR=2.673, 95%CI=1.336-5.350), and social support (OR=0.881, 95%CI=0.797-0.974) (P<0.05) .

Postoperative frailty in patients with colorectal cancer demonstrates three distinct developmental trajectories: "Health Improvement Type""Frailty Improvement Type", and "Persistent Frailty Type". Healthcare professionals should identify the heterogeneous trajectory groups early on, particularly the latter two types, and implement targeted interventions to enhance their long-term health outcomes.

结直肠癌患者术后衰弱发生率较高。多项研究发现衰弱与患者术后并发症、死亡等负性结局相关。衰弱是动态发展过程，但少有研究探讨结直肠癌患者术后衰弱发生发展规律。

采用纵向研究方法探究结直肠癌患者术后衰弱发展轨迹及其影响因素，为此类患者衰弱管理提供理论依据。

采用便利抽样法，选取2022年7—12月于江苏省人民医院就诊的结直肠癌患者为研究对象。收集研究对象的一般资料及其他相关因素，采用Tilburg衰弱量表调查其术前、术后1个月、3个月和6个月的衰弱情况，通过构建增长混合模型识别此类患者术后衰弱发展轨迹，并采用Logistic回归分析结直肠癌患者术后衰弱的影响因素。

共374例患者完成调查。通过拟合4个时点衰弱数据确定3个类别的最优模型，分别命名为"健康提升型"（305例，81.5%）、"衰弱改善型"（25例，6.7%）和"衰弱持续型"（44例，11.8%）。考虑到临床意义将后两类轨迹合并为"衰弱异质性轨迹"。多因素Logistic回归分析结果显示，年龄（OR=1.141，95%CI=1.065~1.223）、营养评分（OR=0.424，95%CI=0.303~0.594）、合并症数量（OR=2.884，95%CI=1.158~7.184）、新辅助治疗（OR=29.510，95%CI=5.511~158.007）、造口建立（OR=37.313，95%CI=8.604~161.819）、术后放化疗（OR=95.071，95%CI=17.664~511.674）、抑郁情况（OR=2.673，95%CI=1.336~5.350）和社会支持（OR=0.881，95%CI=0.797~0.974）是结直肠癌患者衰弱异质性轨迹的影响因素（P<0.05）。

结直肠癌患者术后衰弱呈现"健康提升型""衰弱改善型"和"衰弱持续型"3种不同发展轨迹，医务人员需早期识别包含后两类的衰弱异质性轨迹群体并开展针对性干预以提升其长期健康水平。