Type:
Educational Exhibit
Keywords:
Chest, Lung, Respiratory system, CT, CT-High Resolution, Diagnostic procedure, Biological effects, Tissue characterisation, Prospective, Diagnostic or prognostic study, Multicentre study
Authors:
P. De Souza1, P. Postigo1, D. Alves1, I. Souza1, P. Barros1, A. Souza 1, S. Rêgo2, C. A. P. Fontes3, A. S. A. D. Melo1; 1Niteroi/BR, 2Rio de Janeiro/BR, 3Niterói, RJ/BR
DOI:
10.26044/ecr2020/C-15296
Background
Over 160 million people use marijuana worldwide. Although the health impacts of smoking tobacco are well known, those related to smoking cannabis are still poorly understood.
When comparing both cigarette and marijuana smoke, there is little difference except for the presence of nicotine in the former and cannabinoids in the latter. However, the dynamics of smoking are different. One who smokes marijuana brings about 66% more smoke, with a 33% greater inspiration depth and 400% more inspiratory pause than a who smokes tobacco. Combining smoking dynamics with the absence of a filter, each cannabis cigarette tends to deposit 400% as much tar in the lungs and generate 500% as much carboxyhemoglobin.
To the best of our knowledge, smoking cannabis is related, unlike tobacco, to the development of an uncommon bullous disease. This disease is determined by the presence of paraseptal distribution emphysemas in the pulmonary apices. While the homogeneously distributed centrilobular emphysema predominates in tobacco, probably related to the release of the superoxide anion, marijuana smoke appears to evolve with paraseptal emphysema due to repeated barotraumas.
Some case series have pointed to a possible relationship between cannabis use and the development of vanishing lung syndrome (VLS). However, despite these radiological observations, there is still a large scientific discussion about the relationship between this habit and damage to respiratory function. While some studies point to a dose-dependent relationship between cannabis smoking and airflow obstruction, global respiratory function damage and hyperinflation, others show no impact on FEV1.
The difficulty in understanding the natural history of cannabis use is directly related to the poverty of information available in health system databases and academia. This stems from the still existing social stigma in dealing with the use of psychoactive substances that are considered illegal in most parts of the world. Other contributing factors are high age and high cannabis load in the studies and possible confounding factors with tobacco.
The present work proposes to contribute to the construction of a natural history of cannabis use comparing young and older users. This paper focuses on tomographic changes in the pulmonary structure.
Images for this section:
Fig. 1: Background summary.