Prevalence and incidence of COPD: The Rotterdam study

Abstract

Background: COPD is the third leading cause of death in the world and its global burden is predicted to increase. Although the prevalence of COPD is well documented, only few studies examined its incidence. Methods: In a prospective population-based cohort study (Rotterdam Study) enrolling subjects aged 45 and older, COPD was diagnosed based on an obstructive spirometry (FEV1/FVC Results: In this cohort of 14.926 participants, 692 COPD subjects were identified as prevalent cases and 1.304 cases as incident. The median follow up time was 7.6 years (with a maximum follow up time up to 25 years). The overall incidence rate (IR) was 9.4/1000 person-years (PY) with 95% Confidence Interval (CI) 8.9 to 9.9. The IR was higher in men [14.0/1000 PY, 95% CI 13.0-15.1] than in women [6.5/1000 PY, 95% CI 5.9-7.0], and higher in smokers compared with never-smokers [12.6/1000 PY, 95% CI 11.8-13.3 and 4.3/1000 PY, 95% CI 3.7-4.9, respectively]. Age specific IR ranged between 9.2 and 18.5/1000 PY in males and 3.2 to 8.4/1000 PY in females. The overall incidence increased from the age of 45 to the age of 80 in men and 75 in women. The incidence of COPD in never smokers showed to be stable over a broad age range (from 55 till >80 years old). Conclusion: The overall incidence of COPD in the Rotterdam Study was 9.4/1000 PY, with a higher incidence in males and in smokers.