Tea Rosic1,2, Nitika Sanger3, Balpreet Panesar4, Gary Foster2,5, David C Marsh6,7,8, Launette Rieb9, Lehana Thabane2,5, Andrew Worster2,10, Zainab Samaan11,12. 1. Department of Psychiatry and Behavioural Neurosciences, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada. 2. Department of Health Research Methods, Evidence, and Impact, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada. 3. Medical Sciences Graduate Program, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada. 4. Neurosciences Graduate Program, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada. 5. Biostatistics Unit, Research Institute at St Joseph's Healthcare, 50 Charlton Avenue East, Hamilton, ON, L8N 4A6, Canada. 6. Northern Ontario School of Medicine, 935 Ramsey Lake Rd, Sudbury, ON, P3E 2C6, Canada. 7. Canadian Addiction Treatment Centres, 175 Commerce Valley Drive West, Suite 300, Markham, Ontario, L3T 7P6, Canada. 8. ICES North, 41 Ramsey Lake Road Sudbury, Sudbury, ON, P3E 5J1, Canada. 9. Department of Family Practice, University of British Columbia and St. Paul's Hospital, 1081 Burrard St, Hornby site, Vancouver, BC, V6Z 1Y6, Canada. 10. Department of Medicine, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada. 11. Department of Psychiatry and Behavioural Neurosciences, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada. samaanz@mcmaster.ca. 12. Department of Health Research Methods, Evidence, and Impact, McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada. samaanz@mcmaster.ca.
Abstract
BACKGROUND: As the legalization of recreational cannabis becomes more widespread, its impact on individuals with substance use disorders must be studied. Amidst an ongoing opioid crisis, Canada's legalization of recreational cannabis in October 2018 provides an important setting for investigation. We examined changes to cannabis use patterns in patients receiving medication-assisted treatment (MAT) for opioid use disorder (OUD) following legalization. METHODS: This study includes cross-sectional data from 602 participants recruited 6 months pre-legalization and 788 participants recruited 6 months post-legalization, providing information on cannabis use. Regression analysis was used to estimate the association between legalization and cannabis use patterns. We collected longitudinal urine drug screens (UDSs) detecting cannabis-metabolites for 199 participants recruited pre-legalization and followed prospectively post-legalization. Conditional logistic regression was used to assess the association between legalization and UDS results. RESULTS: Past-month cannabis use was self-reported by 54.8 and 52.3% of participants recruited pre- and post-legalization, respectively. Legalization was not associated with changes in any measured cannabis characteristics: cannabis use (OR 0.91, 95% CI 0.73-1.13), days of use/month (B -0.42, 95% CI - 2.05-1.21), money spent, or cannabis source. There was no association between legalization and prevalence of cannabis use on UDS (OR 1.67, 95% CI 0.93-2.99) or percentage of cannabis-positive UDSs (OR 1.00, 95% CI 0.99-1.01). Participants overwhelmingly reported that legalization would have no impact on their cannabis use (85.7%). CONCLUSIONS: Amongst patients treated for OUD, no significant change in cannabis use was observed following legalization; however, high rates of cannabis use are noted.
BACKGROUND: As the legalization of recreational cannabis becomes more widespread, its impact on individuals with substance use disorders must be studied. Amidst an ongoing opioid crisis, Canada's legalization of recreational cannabis in October 2018 provides an important setting for investigation. We examined changes to cannabis use patterns in patients receiving medication-assisted treatment (MAT) for opioid use disorder (OUD) following legalization. METHODS: This study includes cross-sectional data from 602 participants recruited 6 months pre-legalization and 788 participants recruited 6 months post-legalization, providing information on cannabis use. Regression analysis was used to estimate the association between legalization and cannabis use patterns. We collected longitudinal urine drug screens (UDSs) detecting cannabis-metabolites for 199 participants recruited pre-legalization and followed prospectively post-legalization. Conditional logistic regression was used to assess the association between legalization and UDS results. RESULTS: Past-month cannabis use was self-reported by 54.8 and 52.3% of participants recruited pre- and post-legalization, respectively. Legalization was not associated with changes in any measured cannabis characteristics: cannabis use (OR 0.91, 95% CI 0.73-1.13), days of use/month (B -0.42, 95% CI - 2.05-1.21), money spent, or cannabis source. There was no association between legalization and prevalence of cannabis use on UDS (OR 1.67, 95% CI 0.93-2.99) or percentage of cannabis-positive UDSs (OR 1.00, 95% CI 0.99-1.01). Participants overwhelmingly reported that legalization would have no impact on their cannabis use (85.7%). CONCLUSIONS: Amongst patients treated for OUD, no significant change in cannabis use was observed following legalization; however, high rates of cannabis use are noted.
Authors: Heather McBrien; Candice Luo; Nitika Sanger; Laura Zielinski; Meha Bhatt; Xi Ming Zhu; David C Marsh; Lehana Thabane; Zainab Samaan Journal: CMAJ Open Date: 2019-11-19
Authors: Philippe Lucas; Zach Walsh; Kim Crosby; Robert Callaway; Lynne Belle-Isle; Robert Kay; Rielle Capler; Susan Holtzman Journal: Drug Alcohol Rev Date: 2015-09-14
Authors: Theresa H M Moore; Stanley Zammit; Anne Lingford-Hughes; Thomas R E Barnes; Peter B Jones; Margaret Burke; Glyn Lewis Journal: Lancet Date: 2007-07-28 Impact factor: 79.321
Authors: Laura Zielinski; Meha Bhatt; Nitika Sanger; Carolyn Plater; Andrew Worster; Michael Varenbut; Jeff Daiter; Guillaume Pare; David C Marsh; Dipika Desai; James MacKillop; Meir Steiner; Stephanie McDermid Vaz; Lehana Thabane; Zainab Samaan Journal: Biol Sex Differ Date: 2017-03-30 Impact factor: 5.027