Ochmann Uta, Kotschy-Lang Nicola, Raab Wolfgang, Kellberger Jessica, Nowak Dennis, Jörres Rudolf A
Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine, Inner City Clinic, University Hospital of Munich, Munich, Germany.
Respiration. 2013;86(5):384-92. doi: 10.1159/000345859. Epub 2013 Jan 26.
In patients with chronic lung diseases, the work rate for endurance training is calculated by the maximal work rate (Wmax). Because the assessment bears side effects, a prediction by easier accessible tests would be of practical use.
We addressed the reliability of predicting Wmax on the basis of the 6-min walk distance (6MWD) test and a set of further parameters in patients with different lung diseases.
Baseline data of a longitudinal study including 6MWD, Wmax, peripheral muscle force, lung function, fat-free mass and dyspnea (Modified Medical Research Council score) of 255 men with occupational lung diseases (104 asthma, 69 asbestosis, 42 silicosis, 40 chronic obstructive pulmonary disease) were evaluated.
6MWD correlated with Wmax (r = 0.51, p < 0.05). The product of 6MWD and body weight, in particular fat-free mass, led to an improvement in the correlation of Wmax with 6MWD. Muscle force, lung function and Modified Medical Research Council score correlated moderately but significantly with Wmax (p < 0.05 each). The maximum correlation gained by including 6MWD and further parameters in the prediction equations was r = 0.76 in patients with obstructive lung function impairment and r = 0.61 in asbestosis patients. The residual standard deviations of Wmax predicted by the calculated equations ranged between 20 and 28 W, and the 95% prediction intervals of Wmax ranged between ±47 and ±65 W.
A reliable prediction of individual Wmax by 6MWD or related measures and therefore a replacement by other tests is not possible. Nevertheless, it may be useful for the comparison of average values in epidemiological and clinical studies.
在慢性肺部疾病患者中，耐力训练的工作负荷是通过最大工作负荷（Wmax）来计算的。由于这种评估存在副作用，通过更容易获得的测试进行预测将具有实际用途。
我们探讨了基于6分钟步行距离（6MWD）测试和一组其他参数预测不同肺部疾病患者Wmax的可靠性。
对一项纵向研究的基线数据进行评估，该研究纳入了255名患有职业性肺部疾病的男性（104例哮喘、69例石棉肺、42例矽肺、40例慢性阻塞性肺疾病），包括6MWD、Wmax、外周肌力、肺功能、去脂体重和呼吸困难（改良医学研究委员会评分）。
6MWD与Wmax相关（r = 0.51，p < 0.05）。6MWD与体重（尤其是去脂体重）的乘积使Wmax与6MWD的相关性得到改善。肌力、肺功能和改良医学研究委员会评分与Wmax呈中度但显著相关（均p < 0.05）。在预测方程中纳入6MWD和其他参数后，阻塞性肺功能损害患者的最大相关性为r = 0.76，石棉肺患者为r = 0.61。计算方程预测的Wmax的残余标准差在20至28 W之间，Wmax的95%预测区间在±47至±65 W之间。
通过6MWD或相关测量可靠预测个体Wmax并因此用其他测试替代是不可能的。然而，这可能有助于在流行病学和临床研究中比较平均值。
