Andrés Martínez Josep, Palomino Meneses Rosa, Santiago Josefat Belén
GOC Networking, Barcelona, España.
Arch Bronconeumol. 2008;44 Suppl 2:11-20.
Chronic obstructive pulmonary disease (COPD) is characterized by progressive and incompletely reversible airflow obstruction associated with an anomalous inflammatory response of the lungs, mainly to tobacco smoke. The best indicator of disease progression and severity is measurement of airflow obstruction (forced expiratory volume in 1 second), expressed as a percentage of the predicted value derived from a healthy reference population. Most of the treatments available for COPD have not been shown to clearly affect disease progression or mortality, probably because COPD is a heterogeneous, longstanding process and because there is wide variety in patients' phenotypes, clinical situations, and clinical course. In the last few years, the number of studies on disease progression and mortality in COPD has markedly increased, making survival analysis one of the most important tools for exploiting the resulting data. However, certain methodological factors associated with this type of research, such as the study design, the variables used to measure effect, and determination of the sample, have influenced the conclusions of these studies. Moreover, analysis of disease progression and mortality rates usually entails prolonged follow-up periods and a large number of participants, limiting the funding and continuity of this type of study. In the case of studies of mortality associated with COPD, there are the additional difficulties of identifying the specific cause of death and of identifying the prognostic factors of mortality from the disease, which are the main methodological factors that hamper the possibility of obtaining conclusive data.
慢性阻塞性肺疾病（COPD）的特征是进行性且不完全可逆的气流受限，伴有肺部异常炎症反应，主要是对烟草烟雾的反应。疾病进展和严重程度的最佳指标是气流受限的测量值（1秒用力呼气量），以从健康参考人群得出的预测值的百分比表示。大多数现有的COPD治疗方法尚未显示出能明显影响疾病进展或死亡率，这可能是因为COPD是一个异质性的长期过程，且患者的表型、临床情况和临床病程存在很大差异。在过去几年中，关于COPD疾病进展和死亡率的研究数量显著增加，使得生存分析成为利用所得数据的最重要工具之一。然而，与这类研究相关的某些方法学因素，如研究设计、用于测量效果的变量以及样本的确定，影响了这些研究的结论。此外，对疾病进展和死亡率的分析通常需要较长的随访期和大量参与者，限制了这类研究的资金和持续性。在与COPD相关的死亡率研究中，还存在确定具体死亡原因以及从该疾病中确定死亡率的预后因素的额外困难，这些是阻碍获得确凿数据可能性的主要方法学因素。
