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. Objectives: 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 FEV1/FVC less than the lower limit of normal in individuals under 50 years of age with 10 pack-years or greater of tobacco consumption. Measurements and Main Results: Among 8,064 individuals under 50 years of age with 10 pack-years or greater of tobacco consumption, 1,175 (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 the 14.4-year follow-up, we observed 117 acute hospitalizations with obstructive lung disease, 227 acute hospitalizations with pneumonia, and 185 deaths among the 8,064 younger adults. Compared with individuals without COPD, those with early COPD had multivariable adjusted hazard ratios of 6.42 (95% confidence interval, 3.39-12.2) for acute obstructive lung disease hospitalizations, 2.03 (1.43-2.88) for acute pneumonia hospitalizations, and 1.79 (1.28-2.52) for all-cause mortality. Conclusions: Among individuals under 50 years of age and 10 pack-years or greater of tobacco consumption from the general population, 15% fulfill 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 hospitalizations and early death.