[Spontaneous pneumothorax and lung emphysema in cannabis users]

Abstract

Introduction: If pulmonary complications of tobacco smoking are well documented, those associated with cannabis use are less known.

Objectives: Systematic literature review of data on pneumothorax and lung emphysema in cannabis users.

Documentary sources: Medline, on the period 1980-2018 with the following keywords cannabis or marijuana and pneumothorax or emphysema, limits "title/abstract". Among 97 articles, 42 abstracts have given use to a dual reading to select 20 studies.

Results: Eighteen case reports (8 with SP) showed bullae in the upper lobes in combined cannabis and tobacco smokers (CS) and in the 2 cannabis only smokers (COS). The risk of SP was increased in CS, but not in COS. In patients less than 35-years old presenting with SP, the incidence of bullae on thoracic computed tomography (CT) was higher in CS than in tobacco only smokers (TOS). CT in patients with SP showed no significant difference as regards of the prevalence, location and type of emphysema between CS and TOS. Proportion of low lung density areas was higher in CS than in non-smokers (NS), but was similar in TOS and NS.

Conclusion: These results suggest a cumulative toxic effect of tobacco and cannabis on the risk of SP and lung emphysema.

Keywords: Bullae; Bulles; Cannabis; Emphysème pulmonaire; Lung emphysema; Marijuana; Pneumothorax.