Cannabis Use Is Associated With Recurrence After Primary Spontaneous Pneumothorax.

Primary spontaneous pneumothorax (PSP) is a frequently encountered entity that carries a high rate of recurrence. The current study aims to investigate if cannabis use at time of initial PSP is associated with disease recurrence. Patients presenting with PSP between 2010 and 2018 at a single institution were identified. Exclusion criteria included secondary pneumothorax, severe chronic lung disease, lung cancer, and lost to follow-up. Patients were compared relative to their cannabis usage with Fisher's exact test, Wilcoxon rank-sum test, and logistic regression. Overall, 67 patients (53 male) met inclusion criteria with a median body mass index (BMI) of 21.5 kg/m (IQR 19.1-25.2) and age of 34 years (IQR 22-53). Initial treatment consisted of chest tube in 42 patients (63%), video-assisted thoracoscopic surgery wedge resection in 19 patients (28%), and observation in 6 patients (9%). Cannabis users ( = 28; 42%) had a higher rate of tobacco use (79 vs. 38%; = 0.005), lower BMI [21.0 kg/m (IQR 18.3-23.1) vs. 22.2 kg/m (IQR 19.9-28.6), = 0.037], and were more likely to require intervention at first presentation compared with non-marijuana users. Cannabis use was associated with PSP recurrence when adjusting for tobacco use, BMI, and height (OR 1.85, 95% CI 1.38-18.3, = 0.014). There is a high rate of cannabis usage in patients presenting with PSP. Cannabis usage is associated with PSP recurrence and eventual need for operative intervention.