Wise Robert A, Brown Cynthia D
Division of Pulmonary and Critical Care Medicine, Johns Hopkins Asthma and Allergy Center, Johns Hopkins University School of Medicine, 4B. 72, 5501 Hopkins Bayview Circle, Baltimore, Maryland 21224, USA.
COPD. 2005 Mar;2(1):125-9. doi: 10.1081/copd-200050527.
Simple walking tests are widely used for the assessment of functional status in patients with cardiorespiratory disorders. These tests require far less instrumentation than formal cardiopulmonary exercise tests, but they do require standardization of procedures to achieve reproducible results. The most widely used tests for patients with COPD are the 6-minute walking test (6MWT) and the incremental shuttle walking test (SWT). The 6MWT has been characterized in COPD patients with respect to reproducibility and responsivity to change in health status. The 6MWT results are correlated with pulmonary function, health-related quality of life, maximum exercise capacity, and mortality. The minimal clinically important difference (MCID) for the 6MWT is conservatively estimated to be 54-80 meters using both distributional and discriminative methods. For an individual patient, the 6MWT would need to change by about 86 meters to be statistically confident that there has been a change. The SWT has been less extensively validated than the 6MWT, but has similar reproducibility in COPD (CV = approximately 20%). The SWT results improve with pulmonary rehabilitation and bronchodilation, and are highly correlated with maximum oxygen consumption. There are no studies that address the issue of MCID for the SWT. In addition to the MCID, the design and interpretation of COPD clinical trials should take into account the severity of initial impairment, the asymmetry between positive and negative changes, the proportion of patients who show substantial improvement, and the costs and risks of the treatment.
简单步行测试被广泛用于评估心肺疾病患者的功能状态。与正式的心肺运动测试相比，这些测试所需的仪器设备要少得多，但确实需要程序标准化以获得可重复的结果。慢性阻塞性肺疾病（COPD）患者最常用的测试是6分钟步行测试（6MWT）和递增往返步行测试（SWT）。6MWT在COPD患者中已就可重复性和对健康状况变化的反应性进行了特征描述。6MWT结果与肺功能、健康相关生活质量、最大运动能力和死亡率相关。使用分布法和判别法保守估计，6MWT的最小临床重要差异（MCID）为54 - 80米。对于个体患者，6MWT需要改变约86米才能在统计学上确信有变化。与6MWT相比，SWT的验证程度较低，但在COPD中的可重复性相似（变异系数约为20%）。SWT结果会随着肺康复和支气管扩张而改善，并且与最大耗氧量高度相关。目前尚无研究探讨SWT的MCID问题。除了MCID外，COPD临床试验的设计和解读还应考虑初始损伤的严重程度、阳性和阴性变化之间的不对称性、显示出显著改善的患者比例以及治疗的成本和风险。
