Figure 4.
Risk of acute hospitalizations due to obstructive lung disease and pneumonia and of death in individuals with and without early chronic obstructive pulmonary disease (COPD). Included individuals are under 50 years of age with 10 pack-years or greater of tobacco consumption. Early COPD was defined as FEV1/FVC less than the lower limit of normal. Analyses were adjusted for age (as timescale), sex, smoking status, and pack-years of tobacco consumption. CI = confidence interval; HR = hazard ratio.