Should Primary Spontaneous Pneumothorax Be Considered Secondary in Cannabis Smokers?

Abstract

<bold>Introduction:</bold> Primary spontaneous pneumothorax (PSP) occurs in young, thin individuals without known lung disease. However, cannabis smoking may contribute to lung abnormalities, potentially challenging this definition. This study compares PSP characteristics and outcomes in cannabis smokers. <bold>Methods:</bold> A retrospective study included 183 PSP patients hospitalized in the Pneumology and the Surgery A departments of Charles Nicolle Hospital in Tunis from January 2018 to December 2022. Patients with PSP were divided into two groups: G1 : cannabis smokers (n=81), and G2 : non-cannabis smokers (n=102). <bold>Results:</bold> Cannabis smokers were significantly younger (28±7 years vs. 31±11 years; p=0.026). The only female patient was a non-cannabis smoker. Most cannabis smokers also smoked tobacco (p=0.04). Chest CT was performed in 24 patients (13.1%) at the first PSP episode (11 scans in G1 and 13 scans in G2). Apical bullae were more frequent in cannabis smokers (54.5%) than in non-smokers (7.7%) ; (p=0.018). Similarly, blebs were more common in cannabis smokers ( 63.6% vs 23.1%; p=0.045). Drainage failure was more frequent in G1 (39.5% vs 34.4% ; p=0.4). During surgery, G1 had more often apical bullae (G1: 96.9% vs. G2: 88.6%; p=0.1). Among 78 patients with PSP recurrence, 17 (21.8%) underwent chest CT. No significant differences were found between groups regarding blebs (p=0.22) or emphysema (p=0.7) on CT. In the second episode, all patients had surgery. Apical bullae were macroscopically observed during surgery in 73 patients (94.8%) which were present in all cannabis smokers (G1: 100% vs. G2: 90%; p=0.048). <bold>Conclusion:</bold> PSP in cannabis smokers is associated with a higher prevalence of apical bullae and blebs.