Unit of Respiratory Medicine, Department of Medical and Surgical Sciences, University of Brescia, Brescia, Italy.
Int J Chron Obstruct Pulmon Dis. 2012;7:95-9. doi: 10.2147/COPD.S27480. Epub 2012 Feb 9.
The landmark study of Fletcher and Peto on the natural history of tobacco smoke-related chronic airflow obstruction suggested that decline in the forced expiratory volume in the first second (FEV(1)) in chronic obstructive pulmonary disease (COPD) is slow at the beginning, becoming faster with more advanced disease. The present authors reviewed spirometric data of COPD patients included in the placebo arms of recent clinical trials to assess the lung function decline of each stage, defined according to the severity of airflow obstruction as proposed by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. In large COPD populations the mean rate of FEV(1) decline in GOLD stages II and III is between 47 and 79 mL/year and 56 and 59 mL/year, respectively, and lower than 35 mL/year in GOLD stage IV. Few data on FEV(1) decline are available for GOLD stage I. Hence, the loss of lung function, assessed as expiratory airflow reduction, seems more accelerated and therefore more relevant in the initial phases of COPD. To have an impact on the natural history of COPD, it is logical to look at the effects of treatment in the earlier stages.
弗莱彻和皮托关于烟草烟雾相关慢性气流阻塞自然史的里程碑式研究表明，慢性阻塞性肺疾病（COPD）患者的第一秒用力呼气量（FEV1）下降起初较为缓慢，随着疾病的进展而逐渐加快。本文作者回顾了最近临床试验安慰剂组中 COPD 患者的肺功能数据，以评估每个阶段的肺功能下降情况，这些阶段根据全球慢性阻塞性肺疾病倡议（GOLD）指南提出的气流阻塞严重程度进行定义。在大型 COPD 人群中，GOLD 分期 II 和 III 的 FEV1 年平均下降率分别为 47-79 mL/年和 56-59 mL/年，而 GOLD 分期 IV 则低于 35 mL/年。关于 GOLD 分期 I 的 FEV1 下降数据较少。因此，呼气气流减少评估的肺功能损失似乎在 COPD 的初始阶段更为加速，因此更为相关。为了对 COPD 的自然史产生影响，在早期阶段观察治疗效果是合乎逻辑的。
