Baarends E M, Schols A M, Mostert R, Wouters E F
Dept of Pulmonology, Maastricht University, The Netherlands.
Eur Respir J. 1997 Dec;10(12):2807-13. doi: 10.1183/09031936.97.10122807.
In several studies a correlation between body weight and peak exercise capacity has been found in patients with chronic obstructive pulmonary disease (COPD). In the present study a thorough analysis of the relationship between body composition and peak exercise performance was executed in 62 patients with clinically stable COPD. This was based on the hypothesis that particularly muscle mass, as the largest constituent of both fat-free mass (FFM) and body cell mass, is related to exercise capacity. Body composition was assessed using deuterium and bromide dilution techniques, to measure total body water (TBW) and extracellular water. From these measurements FFM:TBW/0.73, the ratio of ECW/intracellular water (ICW) and ICW-index (ICW/height2) were calculated. Peak exercise performance was measured using an incremental cycle ergometry test. The transfer factor of the lung for carbon monoxide (TL,CO) intrathoracic gas volume (ITGV), maximal expiratory and inspiratory mouth pressure, forced expiratory volume in one second (FEV1), FFM-index (FFM/height2), body mass index (weight/height2) and ICW-index correlated strongly (p<0.01) to peak oxygen consumption (V'O2). The ratio ECW/ICW correlated only weakly, but significantly, with peak V'O2 (r=-0.25, p<0.05). Stepwise regression analysis demonstrated that FFM-index and TL,CO explained 53% of the variation in peak V'O2. The results of this study furthermore indicate that severe FFM depletion is related to a blunted tidal volume response to peak exercise, a decreased peak oxygen pulse and an early anaerobic metabolism in patients with COPD. Depletion of muscle mass, measurable by assessment of fat-free mass, significantly effects peak oxygen consumption, ventilatory response, the oxygen pulse and anaerobic energy metabolism in patients with chronic obstructive pulmonary disease.
在多项研究中，已发现慢性阻塞性肺疾病（COPD）患者的体重与运动能力峰值之间存在关联。在本研究中，对62例临床病情稳定的COPD患者的身体组成与运动能力峰值之间的关系进行了全面分析。这是基于这样一种假设，即肌肉质量作为去脂体重（FFM）和身体细胞质量的最大组成部分，与运动能力相关。使用氘和溴化物稀释技术评估身体组成，以测量全身水（TBW）和细胞外水。根据这些测量结果计算FFM:TBW/0.73、细胞外水与细胞内水（ICW）的比值以及ICW指数（ICW/身高²）。使用递增式自行车测力计测试来测量运动能力峰值。肺一氧化碳转运因子（TL,CO）、胸腔内气体容积（ITGV）、最大呼气和吸气口腔压力、一秒用力呼气容积（FEV1）、FFM指数（FFM/身高²）、体重指数（体重/身高²）和ICW指数与峰值耗氧量（V'O2）密切相关（p<0.01）。细胞外水与细胞内水的比值与峰值V'O2仅呈弱但显著的相关性（r=-0.25，p<0.05）。逐步回归分析表明，FFM指数和TL,CO解释了峰值V'O2变化的53%。本研究结果还表明，严重的FFM消耗与COPD患者运动能力峰值时潮气量反应减弱、峰值氧脉搏降低和早期无氧代谢有关。通过评估去脂体重可测量的肌肉质量消耗，显著影响慢性阻塞性肺疾病患者的峰值耗氧量、通气反应、氧脉搏和无氧能量代谢。
