Cannabis Smoking Is Associated With Cough, Wheezing, and Dyspnea

Many Americans smoke marijuana and rates are increasing, raising concerns about potential effects on pulmonary health. Researchers conducted a systematic review and meta-analysis to examine the association between marijuana use and pulmonary health. They found 22 studies (10 prospective cohort and 12 cross-sectional) that met their inclusion criteria.

• In a pooled analysis of cross-sectional studies with low or moderate risk of bias, current marijuana smoking was associated with cough (odds ratio [OR], 4.4), chronic sputum production (OR, 3.4), wheezing (OR, 2.8), and dyspnea (OR, 1.6). The strength of the evidence was graded “low.”
• Analysis of data on pulmonary function and development of chronic obstructive lung disease failed to show a significant association. The strength of the evidence was graded “insufficient.”

Comments: This study suggests that marijuana smoking is associated with adverse pulmonary symptoms. It may also have a deleterious effect on pulmonary function, but longer and larger studies are needed to assess this.

Darius A. Rastegar, MD

Reference: Ghasemiesfe M, Ravi D, Vali M, et al. Marijuana use, respiratory symptoms, and pulmonary function: a systematic review and meta-analysis. Ann Intern Med. 2018;169:106–115.