Service de Pneumologie, Hôpital Cochin, AP-HP and Université Paris Descartes, Sorbonne Paris Cité, Paris, France.
PLoS One. 2012;7(12):e51048. doi: 10.1371/journal.pone.0051048. Epub 2012 Dec 7.
In COPD patients, mortality risk is influenced by age, severity of respiratory disease, and comorbidities. With an unbiased statistical approach we sought to identify clusters of COPD patients and to examine their mortality risk.
Stable COPD subjects (n = 527) were classified using hierarchical cluster analysis of clinical, functional and imaging data. The relevance of this classification was validated using prospective follow-up of mortality.
The most relevant patient classification was that based on three clusters (phenotypes). Phenotype 1 included subjects at very low risk of mortality, who had mild respiratory disease and low rates of comorbidities. Phenotype 2 and 3 were at high risk of mortality. Phenotype 2 included younger subjects with severe airflow limitation, emphysema and hyperinflation, low body mass index, and low rates of cardiovascular comorbidities. Phenotype 3 included older subjects with less severe respiratory disease, but higher rates of obesity and cardiovascular comorbidities. Mortality was associated with the severity of airflow limitation in Phenotype 2 but not in Phenotype 3 subjects, and subjects in Phenotype 2 died at younger age.
We identified three COPD phenotypes, including two phenotypes with high risk of mortality. Subjects within these phenotypes may require different therapeutic interventions to improve their outcome.
在 COPD 患者中，死亡率的风险受到年龄、呼吸疾病的严重程度和合并症的影响。我们采用无偏倚的统计方法，旨在确定 COPD 患者的聚类，并检查他们的死亡风险。
采用临床、功能和影像学数据的层次聚类分析对稳定的 COPD 患者（n = 527）进行分类。使用前瞻性死亡率随访验证该分类的相关性。
最相关的患者分类是基于三个聚类（表型）。表型 1 包括死亡率非常低的患者，他们的呼吸疾病较轻，合并症的发生率较低。表型 2 和 3 的死亡率较高。表型 2 包括年轻的患者，他们有严重的气流受限、肺气肿和过度充气、低体重指数和较低的心血管合并症发生率。表型 3 包括年龄较大的患者，他们的呼吸疾病较轻，但肥胖和心血管合并症的发生率较高。在表型 2 中，死亡率与气流受限的严重程度相关，但在表型 3 中不相关，并且表型 2 的患者死亡年龄较早。
我们确定了三种 COPD 表型，其中两种表型具有较高的死亡率风险。这些表型中的患者可能需要不同的治疗干预措施来改善他们的预后。
