Phenotypic characterisation of early COPD: a prospective case–control study

Abstract

The phenotypic characteristics of chronic obstructive pulmonary disease (COPD) in individuals younger than 50 years of age (early COPD) are not well defined. This prospective, multicentre, case–control study sought to describe these characteristics and compare them with those of smokers (≥10 pack-years) of similar age with normal spirometry (controls).We studied 92 cases (post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) <0.7) and 197 controls. Results were contrasted with participants with similar inclusion criteria recruited into the ECLIPSE and COPDGene cohorts.Cases had moderate airflow limitation (FEV1 71.3±20.8%) but were often symptomatic, used healthcare resources frequently, had air trapping (residual volume 150.6±55.5% ref.), had reduced diffusing capacity (84.2±20.7% ref.) and had frequent evidence of computed tomography (CT) emphysema (61%). Of note, less than half of cases (46%) had been previously diagnosed with COPD. Interestingly, they also often reported a family history of respiratory diseases and had been hospitalised because of respiratory problems before the age of 5 years more frequently than controls (12% versus 3%, p=0.009). By and large, these observations were reproduced when available in the ECLIPSE and COPDGene cohorts.These results show that early COPD is associated with substantial health impact and significant structural and functional abnormalities, albeit it is often not diagnosed (hence, treated). The fact that a sizeable proportion of patients with early COPD report a family history of respiratory diseases and/or early-life events (including hospitalisations before the age of 5 years) renders further support to the possibility of early-life origin of COPD.

Impact of early life exposures on COPD in adulthood: A systematic review and meta‐analysis

“…The association between risk of adult COPD and childhood serious respiratory infections, pneumonia or bronchitis was reported in 14 studies 6,7,15,16,[20][21][22][23][24][25][26][27][28]50 ; childhood asthma in nine studies 8,15,16,20,28,[34][35][36][37] ; maternal smoking in seven studies 6,15,18,19,23,37,41,51 ; CETS in two studies 40,41 ; child maltreatment in five studies [29][30][31][32][33] ; low birth weight in three studies 6,23,39 ; and premature birth in three studies. 23,28,39 Included participants were older than 40 years, except for studies from the European Community Respiratory Health Survey, in which the average age was about 36 years. 8,26,51 The study population of five studies was evers...…”

“…23,28,39 Included participants were older than 40 years, except for studies from the European Community Respiratory Health Survey, in which the average age was about 36 years. 8,26,51 The study population of five studies was eversmokers 21,23,34,41,51 and two studies included neversmokers. 6,7 Table S1 in the Supporting Information shows the assessment of article quality.…”

“…[6][7][8]22,25,30,35,50,51 The sample of eight articles was not randomly selected. 7,21,22,25,[32][33][34][35] Ten studies used the GOLD lung function criteria for defining and staging COPD 6,7,21,[23][24][25][26][27][28]34,50 and four used prebronchodilator spirometry to define COPD. 8,26,35,51 All studies of the association between child maltreatment and adult COPD were based on self-reported COPD, 29,30,32,33 except for one of hospital discharge records.…”

“…19 Likewise, results from studies of the effect of childhood serious respiratory infections, pneumonia or bronchitis on COPD in adulthood were inconsistent. Some studies indicated that the effect was significant, 6,[20][21][22][23][24][25][26] but others had different results. 7,16,27,28 Recently, some studies indicated that child maltreatment might increase the risk of COPD.…”

“…38 Therefore, a quantitative evaluation of the risk of COPD in individuals with childhood asthma is needed. Furthermore, adulthood COPD has been found to be associated with low birth weight, 6,23,39 premature birth 23,28,39 and CETS, 40,41 although the number of studies is relatively small.…”