Abstract
Cannabis is one of the most widely used recreational drugs world-wide. Despite the high prevalence of cannabis use, we do not understand the potential impact it has on respiratory health. Previous studies have shown that cannabis smoking affects the lungs, although the effects appear to be different to tobacco. The long-term effects of cannabis smoking on small airways remain unclear. This study aimed to investigate the effects of cannabis smoking on small airway function in an adult population at age 45 years.