Background and objective: In contrast to the well-described effects of tobacco smoking upon pulmonary emphysema, with approximately 15% of smokers being affected at the age of 65 years, the effects of marijuana smoking are rarely reported and poorly understood.
Methods: We report a series of 10 patients (mean age 41 +/- 9 years, eight male, two female), who presented over a period of 12 months to our respiratory unit with new respiratory symptoms, and who admitted to regular chronic marijuana smoking (>1 year continuously). Symptoms on presentation were dyspnoea (n = 4), pneumothorax (n = 4) and chest infection (n = 2).
Results: High-resolution CT revealed asymmetrical, variably sized, emphysematous bullae in the upper and mid zones. However, the CXR was normal in four patients and lung function was normal in five.
Conclusions: Marijuana smoking leads to asymmetrical bullous disease, often in the setting of normal CXR and lung function. In subjects who smoke marijuana, these pathological changes occur at a younger age (approximately 20 years earlier) than in tobacco smokers.