Baarends E M, Schols A M, van Marken Lichtenbelt W D, Wouters E F
Department of Pulmonology, University of Limburg, Maastricht, Netherlands.
Am J Clin Nutr. 1997 Jan;65(1):88-94. doi: 10.1093/ajcn/65.1.88.
Tissue depletion often occurs in patients with chronic obstructive pulmonary disease (COPD), even in those that are weight-stable. Limited data are available, however, about changes in body water compartments in chronic wasting diseases such as COPD. The purpose of this study was to measure body composition in severe COPD patients with special attention to fat-free mass (FFM) depletion and the distribution of body water compartments. Total body water (TBW) and extracellular water (ECW) were measured by deuterium and sodium bromide dilution techniques, respectively, in 38 COPD patients (age: 65 +/- 9 y, forced expiratory volume in 1 s: 38 +/- 14% of predicted) in a stable clinical condition. FFM was calculated by assuming a hydration coefficient of 73%. Underweight patients [body mass index (BMI; in kg/m2) < or = 21] were characterized by a significantly lower percentage fat mass than normal-weight patients, but no significant difference was found in the ratio of ECW to intracellular water (ICW)(BMI < or = 21: 0.72 +/- 0.12, BMI > 21: 0.71 +/- 0.16; NS). When the study population was divided into depleted patients (FFM/height2 < or = 15 kg/m2) and nondepleted patients (FFM/height2 > 15 kg/m2), there was no significant difference in the percentage fat mass, but the ECW-ICW ratio was significantly higher in the depleted patients (0.78 +/- 0.16) than in the nondepleted patients (0.66 +/- 0.12, P < 0.05); this was most pronounced in women. In conclusion, it was found that COPD patients with extreme FFM wasting are characterized by an increased ECW-ICW ratio despite a relatively spared fat mass.
组织消耗在慢性阻塞性肺疾病（COPD）患者中经常发生，即使是那些体重稳定的患者。然而，关于慢性消耗性疾病如COPD患者体内水成分变化的数据有限。本研究的目的是测量重度COPD患者的身体组成，特别关注去脂体重（FFM）消耗和体内水成分的分布。采用氘稀释技术和溴化钠稀释技术分别测量了38例临床病情稳定的COPD患者（年龄：65±9岁，第1秒用力呼气容积：占预计值的38±14%）的总体水（TBW）和细胞外水（ECW）。通过假设水合系数为73%来计算FFM。体重过轻的患者[体重指数（BMI；单位：kg/m2）≤21]的脂肪量百分比显著低于体重正常的患者，但细胞外水与细胞内水（ICW）的比值无显著差异（BMI≤21：0.72±0.12，BMI>21：0.71±0.16；无显著性差异）。当将研究人群分为消耗患者（FFM/身高2≤15 kg/m2）和非消耗患者（FFM/身高2>15 kg/m2）时，脂肪量百分比无显著差异，但消耗患者的ECW-ICW比值（0.78±0.16）显著高于非消耗患者（0.66±0.12，P<0.05）；这在女性中最为明显。总之，研究发现，尽管脂肪量相对保留，但FFM极度消耗的COPD患者的特征是ECW-ICW比值增加。
