Cannabis and pneumothorax

  • Research type

    Research Study

  • Full title

    What is the risk of pneumothorax in cannabis smokers?

  • IRAS ID

    311724

  • Contact name

    Stefan J Marciniak

  • Contact email

    sjm20@cam.ac.uk

  • Sponsor organisation

    Cambridge University Hospitals NHS Foundation Trust and University of Cambridge

  • Duration of Study in the UK

    1 years, 5 months, 31 days

  • Research summary

    Cannabis is a psychoactive compound and the most widely used illegal drug in the UK. Despite the growing interest in its therapeutic potential, cannabis smoke shares much of the chemical profile and carcinogens as tobacco, and yet the smoking technique – deeper inhalation and longer breath holding time – results in greater deposition of particulates in the airway. Consequently, the smoke from a single cannabis ‘joint’ has may be equivalent in lung pathophysiology to smoking more than 20 tobacco cigarettes daily. Therefore, although cannabis is often smoked less frequently than tobacco, it has the potential to be at least equally harmful. Unsurprisingly, considerable evidence links cannabis use to respiratory diseases. Given that one in 13 adults report smoking cannabis in the last year, it is crucial that we fully explore the risks of cannabis use on the respiratory system

    Pneumothorax occurs when there is air in the pleural space owing to lung or chest wall perforation. Spontaneous perforation of the lung can occur due to genetic or environmental factors including smoking. While the role of tobacco smoke in emphysema and secondary pneumothorax is well appreciated, relatively few studies have explored the relationship between cannabis and pneumothorax.

    In this study we will compare the frequency of cannabis smoking in patients attending the Cambridge Pneumothorax Clinic with a similar population matched for age, gender and ethnicity, recruited from other clinics in Cambridge University Hospitals. This so-called case-control approach will allow us to estimate the risk of pneumothorax associated with cannabis smoking in our local population.

  • REC name

    London - Brighton & Sussex Research Ethics Committee

  • REC reference

    23/LO/0098

  • Date of REC Opinion

    21 Apr 2023

  • REC opinion

    Further Information Favourable Opinion