Eaton Tam, Young Pam, Milne David, Wells Athol U
Department of Respiratory Services, Green Lane Hospital, Auckland, New Zealand.
Am J Respir Crit Care Med. 2005 May 15;171(10):1150-7. doi: 10.1164/rccm.200405-578OC. Epub 2005 Jan 7.
Resting pulmonary function and exercise variables are widely used to stage and monitor idiopathic interstitial pneumonia (IIP). However, the variability of exercise data (maximal exercise and the 6-minute walk test) has not been evaluated definitively. We have prospectively quantified the reproducibility of resting and exercise functional data in fibrotic IIP (idiopathic pulmonary fibrosis, fibrotic nonspecific interstitial pneumonia) and have evaluated interrelationships between variables. Thirty consecutive patients with fibrotic IIP underwent serial resting pulmonary function tests, 6-minute walk (n = 29), and maximal exercise (n = 24) at an interval of 1 week, with all testing performed in accordance with American Thoracic Society standards. Within-subject reproducibility was excellent for 6-minute walk distance (SD/mean = 4.2%) and clinically acceptable for resting pulmonary function indices and VO(2)max on maximal exercise testing. However, the amplitude of oxygen desaturation at the end of exercise was poorly reproducible in both 6-minute walk and maximal exercise testing (SD/mean > 25%). There was a highly significant relationship between VO2max on maximal exercise testing and 6-minute walk distance (r(s) = 0.78, p < 0.0001). In fibrotic IIP, the excellent reproducibility of the 6-minute walk distance is a major advantage in routine staging and monitoring, whereas maximal exercise variables are poorly reproducible.
静息肺功能和运动变量被广泛用于特发性间质性肺炎（IIP）的分期和监测。然而，运动数据（最大运动和6分钟步行试验）的变异性尚未得到明确评估。我们前瞻性地量化了纤维化IIP（特发性肺纤维化、纤维化非特异性间质性肺炎）中静息和运动功能数据的可重复性，并评估了变量之间的相互关系。30例连续的纤维化IIP患者每隔1周进行系列静息肺功能测试、6分钟步行试验（n = 29）和最大运动试验（n = 24），所有测试均按照美国胸科学会标准进行。6分钟步行距离的受试者内可重复性极佳（标准差/均值 = 4.2%），静息肺功能指标和最大运动试验中的VO₂max的可重复性在临床上可以接受。然而，6分钟步行试验和最大运动试验中运动结束时的氧饱和度下降幅度的可重复性较差（标准差/均值 > 25%）。最大运动试验中的VO₂max与6分钟步行距离之间存在高度显著的相关性（斯皮尔曼相关系数r(s) = 0.78，p < 0.0001）。在纤维化IIP中，6分钟步行距离的极佳可重复性是常规分期和监测的一个主要优势，而最大运动变量的可重复性较差。
