Fujidera Keijin-kai Clinic, Fujidera, Japan.
Nishinokyou Hospital, Nara, Japan.
Nephron. 2023;147(5):251-259. doi: 10.1159/000526866. Epub 2022 Oct 21.
Computed tomography (CT) can accurately measure muscle mass, which is necessary for diagnosing sarcopenia, even in dialysis patients. However, CT-based screening for such patients is challenging, especially considering the availability of equipment within dialysis facilities. We therefore aimed to develop a bedside prediction model for low muscle mass, defined by the psoas muscle mass index (PMI) from CT measurement.
Hemodialysis patients (n = 619) who had undergone abdominal CT screening were divided into the development (n = 441) and validation (n = 178) groups. PMI was manually measured using abdominal CT images to diagnose low muscle mass by two independent investigators. The development group's data were used to create a logistic regression model using 42 items extracted from clinical information as predictive variables; variables were selected using the stepwise method. External validity was examined using the validation group's data, and the area under the curve (AUC), sensitivity, and specificity were calculated.
Of all subjects, 226 (37%) were diagnosed with low muscle mass using PMI. A predictive model for low muscle mass was calculated using ten variables: each grip strength, sex, height, dry weight, primary cause of end-stage renal disease, diastolic blood pressure at start of session, pre-dialysis potassium and albumin level, and dialysis water removal in a session. The development group's adjusted AUC, sensitivity, and specificity were 0.81, 60%, and 87%, respectively. The validation group's adjusted AUC, sensitivity, and specificity were 0.73, 64%, and 82%, respectively.
DISCUSSION/CONCLUSION: Our results facilitate skeletal muscle screening in hemodialysis patients, assisting in sarcopenia prophylaxis and intervention decisions.
计算机断层扫描(CT)可以准确测量肌肉量,这对于诊断肌肉减少症(sarcopenia)是必要的,即使是在透析患者中也是如此。然而,对于此类患者进行 CT 筛查具有挑战性,尤其是考虑到透析设施内设备的可用性。因此,我们旨在开发一种基于床旁的低肌肉量预测模型,该模型由 CT 测量的腰大肌肌肉指数(psoas muscle mass index,PMI)定义。
对接受过腹部 CT 筛查的血液透析患者(n = 619)进行分组,分为开发组(n = 441)和验证组(n = 178)。使用腹部 CT 图像手动测量 PMI,由两名独立研究者诊断低肌肉量。使用来自临床信息的 42 个项目作为预测变量,通过逐步法从开发组数据中创建逻辑回归模型;使用这些变量进行选择。使用验证组的数据检验外部有效性,并计算曲线下面积(area under the curve,AUC)、敏感度和特异性。
在所有患者中,有 226 例(37%)根据 PMI 诊断为低肌肉量。使用十个变量计算了低肌肉量的预测模型:每个握力、性别、身高、干体重、终末期肾病的主要病因、治疗开始时的舒张压、透析前血钾和白蛋白水平,以及一次透析中透析水的清除量。开发组的调整 AUC、敏感度和特异性分别为 0.81、60%和 87%。验证组的调整 AUC、敏感度和特异性分别为 0.73、64%和 82%。
讨论/结论:我们的结果促进了血液透析患者的骨骼肌筛查,有助于进行肌肉减少症的预防和干预决策。