“In [this] cohort of ever-tobacco smokers of ≥20 pack-years with established COPD or at risk of developing COPD, … a history of current and/or former smoking of marijuana of any cumulative lifetime amount was not found to be associated with a significantly …

Cannabis use is not associated with an elevated risk of chronic obstructive pulmonary disease (COPD), even among those possessing a clinically high risk for developing the disease, according to longi…