Gershon et al used Canadian health administrative databases to identify all new diagnoses of COPD in Ontario from 1996-2010, a cohort of 13 million people. Lifetime risk of COPD (by age 80) was 27.6%.

Smoking status was not available/included in the analysis. These were physicians' diagnoses of COPD (using a validated case definition); there was no spirometric data to confirm. Authors point out that COPD is underdiagnosed and spirometry more sensitive than clinical diagnosis; therefore, the incidence should be at least this high.

Gershon AS et al. Lifetime risk of developing chronic obstructive pulmonary disease: a longitudinal population study. Lancet 2011;378:991-996.