Palange P, Forte S, Felli A, Galassetti P, Serra P, Carlone S
II Patologia Medica, University of Rome La Sapienza Italy.
Chest. 1995 May;107(5):1206-12. doi: 10.1378/chest.107.5.1206.
We hypothesized that in patients with COPD, poor nutritional status adversely influences exercise tolerance by limiting aerobic capacity of exercising muscles. In 28 patients with stable COPD, we correlated nutritional status with gas exchange indexes obtained during maximal incremental cycle ergometer exercise and with respiratory function parameters. On the basis of percent of ideal body weight (%IBW), patients were divided into three groups (GP): GP1 (n = 8, %IBW < 90); GP2 (n = 13, %IBW > or = 90 < 110); and GP3 (n = 7, %IBW > or = 110). When compared with normally nourished individuals (GPs 2 and 3), malnourished GP1 patients showed greater reduction in maximal workload and in peak O2 uptake (VO2 peak), with earlier onset of metabolic acidosis (anaerobic threshold [AT]); in addition, indexes reflecting O2 cost of ventilation were higher in GP1. Nutritional status could be correlated with exercise tolerance (VO2 peak, r = 0.82, p < 0.0001), with onset of metabolic acidosis (AT, r = 0.69, p < 0.0001) and with dead space/tidal volume ratio (VD/VT, r = -0.59, p < 0.001). Body weight was inversely correlated with indexes that are likely to reflect the increase in O2 cost of ventilation. We conclude that in patients with stable COPD, (1) malnutrition significantly affects muscle aerobic capacity and exercise tolerance, and (2) high wasted ventilation and O2 cost of ventilation may be responsible for the weight loss.
我们假设，在慢性阻塞性肺疾病（COPD）患者中，营养状况不佳会通过限制运动肌肉的有氧能力对运动耐力产生不利影响。在28例稳定期COPD患者中，我们将营养状况与最大递增式蹬车运动期间获得的气体交换指标以及呼吸功能参数进行了关联分析。根据理想体重百分比（%IBW），患者被分为三组（GP）：GP1组（n = 8，%IBW < 90）；GP2组（n = 13，%IBW≥90 < 110）；以及GP3组（n = 7，%IBW≥110）。与营养正常的个体（GP2组和GP3组）相比，营养不良的GP1组患者在最大工作量和峰值摄氧量（VO2峰值）方面的下降幅度更大，代谢性酸中毒（无氧阈值[AT]）出现得更早；此外，反映通气氧耗的指标在GP1组中更高。营养状况与运动耐力（VO2峰值，r = 0.82，p < 0.0001）、代谢性酸中毒的发生（AT，r = 0.69，p < 0.0001）以及死腔/潮气量比值（VD/VT，r = -0.59，p < 0.001）相关。体重与可能反映通气氧耗增加的指标呈负相关。我们得出结论，在稳定期COPD患者中，（1）营养不良会显著影响肌肉有氧能力和运动耐力，（2）高无效通气和通气氧耗可能是体重减轻的原因。
