Prevalence, Characteristics, and Prognosis of Early COPD: The Copenhagen General Population Study

Rationale: Identification of younger adults at high risk of developing chronic obstructive pulmonary disease (COPD) could lead to implementation of preventive measures before disease onset and halt progression. Objective: To investigate the prevalence, characteristics, and prognosis of individuals with early COPD in the general population. Methods: We investigated 105 630 randomly chosen adults from a Danish contemporary population-based cohort. Early COPD was defined as forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC)<the lower limit of normal (LLN) in individuals aged <50 years with ≥10 pack-years of tobacco consumption. Measurements and Main Results: Among 8064 individuals aged <50 years with ≥10 pack-years of tobacco consumption, 1175 (15%) had early COPD, of whom 58% were current smokers. Individuals with early COPD more often had chronic respiratory symptoms, severe lung function impairment, asthma, and a history with bronchitis/pneumonia. During 14.4 years follow-up, we observed 117 acute hospitalisations with obstructive lung disease, 227 acute hospitalisations with pneumonia, and 185 deaths among the 8064 younger adults. Compared to individuals without COPD, those with early COPD had multivariable adjusted hazard ratios (HRs) of 6.42(95% confidence interval:3.39-12.2) for acute obstructive lung disease hospitalisations, 2.03(1.43-2.88) for acute pneumonia hospitalisations, and 1.79(1.28-2.52) for all-cause mortality. Conclusions: Among individuals aged <50 years and ≥10 pack-years of tobacco consumption from the general population, 15% fulfil criteria of early COPD. Individuals with early COPD more often have chronic respiratory symptoms and severe lung function impairment, and an increased risk of acute respiratory hospitalisations and early death.