第三腰椎骨骼肌质量指数对炎症性肠病患者药物治疗的影响

Impact of the third lumbar skeletal muscle index on drug therapy of patients with inflammatory bowel disease

目的研究以第三腰椎骨骼肌质量指数(the third lumbar skeletal muscle index,L3-SMI)定义肌少症,调查其在炎症性肠病(inflammatory bowel disease,IBD)人群中的患病率,探讨肌少症对于IBD患者药物治疗的影响。方法回顾分析山西医科大学第一医院2018年12月至2022年12月住院治疗的230例IBD患者的基线腹部CT图像获取L3-SMI,行受试者工作特征曲线分析获取最优截断值定义肌少症。IBD组包括溃疡性结肠炎患者164例,克罗恩病患者66例,纳入正常对照组100例。收集体重指数(body mass index,BMI)、白蛋白、前白蛋白和疾病活动度、治疗药物等临床资料和生化指标,随访结局包括基线药物治疗方案优化、使用新的生物制剂或联合药物治疗。采用多变量Logistic回归分析,筛选影响药物治疗升级的危险因素,构建列线图,并评价其对IBD患者药物治疗升级的预测能力。结果研究中,IBD组肌少症患病率39.6%,其中溃疡性结肠炎患者肌少症患病率36.0%,克罗恩病患者肌少症患病率48.5%。IBD患者营养不良(BMI<18.5)的患病率为18.7%,但有69.2%的IBD合并肌少症患者BMI值≥18.5。IBD组中位L3-SMI显著低于正常对照组(36.30 cm^(2)/m^(2)比39.37 cm^(2)/m^(2),P=0.004)。肌少症(OR 3.33,95%CI 1.06~10.50,P=0.040)与IBD患者药物治疗升级相关。基于患者年龄、肌少症、白蛋白、BMI建立列线图模型,预测模型曲线下面积为0.762(95%CI 0.691~0.834,P<0.05),提示该预测模型区分度良好;校准曲线及Hosmer-Lemeshow拟合优度检验表明,该模型的预测值与实际测量值具有良好的一致性(χ^(2)=11.906,P=0.156);绘制决策曲线表明,预测模型有一定的临床效益。结论肌少症在IBD患者中普遍存在,与IBD患者药物治疗升级有关。

Objective To investigate the prevalence of sarcopenia as defined by the third lumbar skeletal muscle index(L3-SMI)and explore its impact on drug therapy in patients with inflammatory bowel disease(IBD).Methods The baseline abdominal CT images of 230 patients with IBD hospitalized in the First Hospital of Shanxi Medical University from December 2018 to December 2022 were retrospectively analyzed to obtain L3-SMI.The optimal cut-off value of L3-SMI to define sarcopenia was determined using receiver operating characteristic curve analysis.The IBD group included 164 cases of ulcerative colitis(UC)and 66 cases of Crohn's disease(CD),compared with 100 cases of the normal control.The clinical data and biochemical indicators,such as body mass index(BMI),albumin(ALB),pre-albumin(PA),disease activity and therapeutic drugs,were collected.Outcomes were followed up,including the optimization of baseline drug therapy,the initiation of additional biological agents or combined drug therapy.Multivariate logistic regression analysis was used to identify risk factors for the escalation of drug therapy,and the nomogram was constructed and evaluated for the prediction of drug regimen escalation in patients with IBD.Results The prevalence of sarcopenia in the IBD population in this study was 39.6%,among whom 36.0%were with ulcerative colitis and 48.5%with Crohn's disease.The prevalence of malnutrition(BMI<18.5)in IBD patients was 18.7%,whereas 69.2%of patients with concurrent IBD and sarcopenia had a BMI≥18.5.The median L3-SMI of IBD patients was significantly lower than that of normal controls(36.30 cm^(2)/m^(2)vs.39.37 cm^(2)/m^(2),P=0.004).Sarcopenia(OR=3.33,95%CI:1.06 to 10.50,P=0.040)was associated with the escalation of drug therapy in patients with IBD.Based on the patient's age,presence or absence of sarcopenia,albumin and BMI,the nomogram prediction model was established,with the area under the curve(AUC)of 0.762(95%CI:0.691 to 0.834),showing good discriminating performance.The calibration curve and Hosmer-Lemeshow goodness-of-fit test demonstrated good consistency between the predicted and observed data(χ^(2)=11.906,P=0.156).Decision curve analysis showed potential benefits of the prediction model in clinical settings.Conclusion Sarcopenia is common in patients with IBD,which is related to the escalation of drug therapy in patients with IBD.