News from ISGlobal
A large study with multiple cohorts reveals that the classification of Chronic Obstructive Pulmonary Disease (COPD) into mutually exclusive subgroups is poorly reproducible across different cohorts, and that COPD is better characterized by continuous traits that can coexist to varying degrees within the same person. The study, led by ISGlobal, was published in Thorax.
COPD is a highly heterogeneous disease and there is little consensus on the existence and definition of different subtypes of COPD. Several groups have used cluster analysis to identify disease subtypes. However, the reproducibility of this classification has been relatively low, calling into question the use of this type of research for the clinical management of the disease in the short-term.
More than 1,700 persons with COPD were analysed using the same algorithm and the same COPD-related characteristics across cohorts. The results show that the reproducibility of COPD classification into subtypes was moderate to low. In contrast, relationships between individual clinical manifestations were more consistent. These manifestations respond to a continuous spectrum of disease severity and can coexist to varying degrees within the same patient. “This means that COPD phenotypical heterogeneity is better explained if one considers the individual traits rather than trying to classify the patients in well-defined groups” explains Judith Garcia-Aymerich, study coordinator.
Castaldi PJ, Benet M, Petersen H, et al. Do COPD subtypes really exist? COPD heterogeneity and clustering in 10 independent cohorts. Thorax. 2017 Jun 21. doi: 10.1136/thoraxjnl-2016-209846.