Characterisation of COPD heterogeneity in the ECLIPSE cohort

Abstract

BackgroundChronic obstructive pulmonary disease (COPD) is a complex condition with pulmonary and extra-pulmonary manifestations. This study describes the heterogeneity of COPD in a large and well characterised and controlled COPD cohort (ECLIPSE).MethodsWe studied 2164 clinically stable COPD patients, 337 smokers with normal lung function and 245 never smokers. In these individuals, we measured clinical parameters, nutritional status, spirometry, exercise tolerance, and amount of emphysema by computed tomography.ResultsCOPD patients were slightly older than controls and had more pack years of smoking than smokers with normal lung function. Co-morbidities were more prevalent in COPD patients than in controls, and occurred to the same extent irrespective of the GOLD stage. The severity of airflow limitation in COPD patients was poorly related to the degree of breathlessness, health status, presence of co-morbidity, exercise capacity and number of exacerbations reported in the year before the study. The distribution of these variables within each GOLD stage was wide. Even in subjects with severe airflow obstruction, a substantial proportion did not report symptoms, exacerbations or exercise limitation. The amount of emphysema increased with GOLD severity. The prevalence of bronchiectasis was low (4%) but also increased with GOLD stage. Some gender differences were also identified.ConclusionsThe clinical manifestations of COPD are highly variable and the degree of airflow limitation does not capture the heterogeneity of the disease.

Symptoms and the body: Taking the inferential leap

“…For example, there is a poor correspondence between somatic symptoms and objective disease severity in about 50% of asthma patients depending on the measure (Janssens et al, 2009). In chronic obstructive pulmonary disease (COPD), large scale studies on several thousands of patients showed large between-person variability in the relationship between objective airflow limitation (FEV1) and self-reported breathlessness, with a modest correlation overall (r = 0.36, Agusti et al, 2010;r = 0.28, Müllerová et al, 2014).…”

Evaluation of clinical variables according to follow-up times in COPD: results from ON-SINT cohort

“…This is interesting because some previous analysis lasted only a few years. [5,7,19] According to our data, differences are found between our study groups with a cutoff of 6.2 years, which suggests that cohorts should have longer follow-ups if we wish to adequately establish the variability in FEV 1 decline. [20]…”

“…[4] However, more recent research is challenging this concept, since FEV 1 does not always decline, and this decline may vary,[5] as various rates of FEV 1 decline have been described depending on the severity of the disease,[6] and symptoms do not correlate with FEV 1 at the individual level. [7,8]…”

“…However, evidence on the clinical presentation of the disease over time may not support this statement. Follow-up times in initial cohort studies were restricted to a few years,[5,7] hence longer observational periods were required to yield more solid conclusions. More recently, longer studies have provided new information on lung function decline, evaluating its progression and additionally setting the importance of lung development at earlier ages as a determinant factor of lung function impairment in adult life.…”

Reducción de la actividad física en pacientes con enfermedad pulmonar obstructiva crónica

“…En el caso particular de las etapas GOLD y la disnea (MMRC), la difi cultad se explica porque en cada etapa GOLD la magnitud de la disnea es muy variable, como lo demuestra la Figura 5, y como ha sido recientemente destacado por otros 33 . Además, la AF no sólo depende de alguna característica fi siológica particular, sino también de aspectos psicosociales y ambientales (estado ocupacional, estado civil, presencia de depresión, entre otros).…”