Wan C Tan1, Jean Bourbeau2, Shawn D Aaron3, James C Hogg4, François Maltais5, Paul Hernandez6, Darcy D Marciniuk7, Kenneth R Chapman8, Teresa To9, J Mark FitzGerald10, Brandie L Walker11, Jeremy Road10, Liyun Zheng4, Guohai Zhou4, Trevor Yau4, Andrea Benedetti2, Denis O'Donnell12, Don D Sin4. 1. The University of British Columbia, Center for Heart Lung Innovation, St Pauls's Hospital, Vancouver, BC, Canada wan.tan@hli.ubc.ca. 2. Research Institute McGill University Health Center, McGill University, Montreal, QC, Canada. 3. The Ottawa Hospital Research Institute, University of Ottawa, Ottawa, ON, Canada. 4. The University of British Columbia, Center for Heart Lung Innovation, St Pauls's Hospital, Vancouver, BC, Canada. 5. Institut Universitaire de cardiologie et de pneumologie de Québec, Université Laval, Quebec City, QC, Canada. 6. Dept of Medicine, Dalhousie University, Halifax, NS, Canada. 7. Respiratory Research Centre, University of Saskatchewan, Saskatoon, SK, Canada. 8. Toronto General Hospital Research Institute, University of Toronto, Toronto, ON, Canada. 9. Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada. 10. University of British Columbia, Dept of Medicine, Vancouver General Hospital, Vancouver, BC, Canada. 11. Dept of Medicine, University of Calgary, Calgary, AB, Canada. 12. Division of Respiratory and Critical Care Medicine, Queen's University, Kingston, ON, Canada.
Abstract
BACKGROUND: Previous studies have associated marijuana exposure with increased respiratory symptoms and chronic bronchitis among long-term cannabis smokers. The long-term effects of smoked marijuana on lung function remain unclear. METHODS: We determined the association of marijuana smoking with the risk of spirometrically defined chronic obstructive pulmonary disease (COPD) (post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity ratio <0.7) in 5291 population-based individuals and the rate of decline in FEV1 in a subset of 1285 males and females, aged ≥40 years, who self-reported use (or non-use) of marijuana and tobacco cigarettes and performed spirometry before and after inhaled bronchodilator on multiple occasions. Analysis for the decline in FEV1 was performed using random mixed effects regression models adjusted for age, sex and body mass index. Heavy tobacco smoking and marijunana smoking was defined as >20 pack-years and >20 joint-years, respectively. RESULTS: ∼20% of participants had been or were current marijuana smokers with most having smoked tobacco cigarettes in addition (83%). Among heavy marijuana users, the risk of COPD was significantly increased (adjusted OR 2.45, 95% CI 1.55-3.88). Compared to never-smokers of marijuana and tobacco, heavy marijuana smokers and heavy tobacco smokers experienced a faster decline in FEV1 by 29.5 mL·year-1 (p=0.0007) and 21.1 mL·year-1 (p<0.0001), respectively. Those who smoked both substances experienced a decline of 32.31 mL·year-1 (p<0.0001). INTERPRETATION: Heavy marijuana smoking increases the risk of COPD and accelerates FEV1 decline in concomitant tobacco smokers beyond that observed with tobacco alone.
BACKGROUND: Previous studies have associated marijuana exposure with increased respiratory symptoms and chronic bronchitis among long-term cannabis smokers. The long-term effects of smoked marijuana on lung function remain unclear. METHODS: We determined the association of marijuana smoking with the risk of spirometrically defined chronic obstructive pulmonary disease (COPD) (post-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity ratio <0.7) in 5291 population-based individuals and the rate of decline in FEV1 in a subset of 1285 males and females, aged ≥40 years, who self-reported use (or non-use) of marijuana and tobacco cigarettes and performed spirometry before and after inhaled bronchodilator on multiple occasions. Analysis for the decline in FEV1 was performed using random mixed effects regression models adjusted for age, sex and body mass index. Heavy tobacco smoking and marijunana smoking was defined as >20 pack-years and >20 joint-years, respectively. RESULTS: ∼20% of participants had been or were current marijuana smokers with most having smoked tobacco cigarettes in addition (83%). Among heavy marijuana users, the risk of COPD was significantly increased (adjusted OR 2.45, 95% CI 1.55-3.88). Compared to never-smokers of marijuana and tobacco, heavy marijuana smokers and heavy tobacco smokers experienced a faster decline in FEV1 by 29.5 mL·year-1 (p=0.0007) and 21.1 mL·year-1 (p<0.0001), respectively. Those who smoked both substances experienced a decline of 32.31 mL·year-1 (p<0.0001). INTERPRETATION: Heavy marijuana smoking increases the risk of COPD and accelerates FEV1 decline in concomitant tobacco smokers beyond that observed with tobacco alone.
Authors: Matthew F Fantauzzi; Jennifer A Aguiar; Benjamin J-M Tremblay; Michael J Mansfield; Toyoshi Yanagihara; Abiram Chandiramohan; Spencer Revill; Min Hyung Ryu; Chris Carlsten; Kjetil Ask; Martin Stämpfli; Andrew C Doxey; Jeremy A Hirota Journal: ERJ Open Res Date: 2020-12-14
Authors: Matthew F Fantauzzi; Steven P Cass; Joshua J C McGrath; Danya Thayaparan; Peiyao Wang; Martin R Stampfli; Jeremy A Hirota Journal: ERJ Open Res Date: 2021-07-19