Lima Carla Cristina, Godoy Maria Eduarda, Ferreira Fratoni Débora Kellen, Paulin Elaine
Universidade do Estado de Santa Catarina, Florianópolis, Brazil.
PeerJ. 2025 Jul 8;13:e19157. doi: 10.7717/peerj.19157. eCollection 2025.
Hemodialysis patients often experience functional limitations that are challenging to assess due to equipment and space constraints. The 6-min step test (6MST) requires little space and a small standardized ergometer, making it more accessible and feasible in various healthcare settings, when compared to the cardiopulmonary exercise test (CPET) and the 6-min walk test (6MWT). Thus, the aim of this study is to evaluate the test-retest reliability and concurrent validity of the 6MST for assessing the functional capacity of hemodialysis patients.
Assessments conducted included anthropometry, spirometry, 6MWT, and 6MST. These two tests were randomized and performed on alternate days. Two 6MSTs and two 6MWTs were conducted with a minimum interval of 30 min between them.
The study involved 32 participants, 67% men ( = 22) and 33% women ( = 10), with an average age of 57 ± 13 years and body mass index (BMI) of 28.6 ± 5.2 kg/m. The 6MST demonstrated high test-retest reliability (ICC = 0.94 (95% CI [0.85-0.97]; < 0.001)) and a strong correlation between the number of steps performed in the 6MST and the distance covered in the 6MWT (r = 0.87; < 0.001). A learning effect was observed, with a 7% improvement on retesting.
The 6MST provides a feasible, reliable assessment option for hemodialysis patients and could be easily implemented in clinics lacking space and specialized equipment. Limitation of the present study are being a single-center investigation with a small sample size, thus limiting generalizability, and the variability of patient conditions, which may have influenced the results. Future research should explore the 6' long-term stability, responsiveness, and impact on patient-centered outcomes, as well as its applicability across different hemodialysis populations and clinical settings, to improve its clinical usefulness.
血液透析患者常存在功能受限情况，由于设备和空间限制，这些功能受限难以评估。与心肺运动试验（CPET）和6分钟步行试验（6MWT）相比，6分钟阶梯试验（6MST）所需空间小，仅需一个小型标准化测力计，因此在各种医疗环境中更易于实施且可行。因此，本研究旨在评估6MST在评估血液透析患者功能能力方面的重测信度和同时效度。
进行的评估包括人体测量、肺功能测定、6MWT和6MST。这两项测试随机安排，隔日进行。进行了两次6MST和两次6MWT，每次测试之间的间隔至少为30分钟。
该研究纳入了32名参与者，其中67%为男性（n = 22），33%为女性（n = 10），平均年龄为57±13岁，体重指数（BMI）为28.6±5.2kg/m²。6MST显示出较高的重测信度（组内相关系数ICC = 0.94（95%置信区间[0.85 - 0.97]；P < 0.001）），且6MST中所走步数与6MWT中所覆盖距离之间存在强相关性（r = 0.87；P < 0.001）。观察到存在学习效应，重测时提高了7%。
6MST为血液透析患者提供了一种可行、可靠的评估选择，并且可以在缺乏空间和专业设备的诊所中轻松实施。本研究的局限性在于为单中心研究且样本量小，从而限制了普遍性，以及患者病情的变异性可能影响了结果。未来的研究应探索6MST的长期稳定性、反应性以及对以患者为中心的结局的影响，以及其在不同血液透析人群和临床环境中的适用性，以提高其临床实用性。
