Lavinia Baltes-Flueckiger, Regine Steinauer, Maximilian Meyer, Adrian Guessoum, Oliver Herrmann, Christoph Felix Mosandl, Jens Kronschnabel, Eva-Maria Pichler, Marc Vogel, Marc Walter
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引用次数: 0
Abstract
Aims: We measured the effects of public health-oriented cannabis access compared with the illegal market on cannabis use and related mental health outcomes in adult cannabis users.
Design: This was a two-arm, parallel group, open-label, randomized controlled trial. Follow-up outcome measurement took place after 6 months.
Setting: The study was conducted in Basel-Stadt, Switzerland.
Participants: A total of 378 adult (aged ≥18 years) cannabis users were enrolled and randomized between August 2022 and March 2023, although only 374 users who completed baseline measures could be included.
Intervention and comparator: Participants were randomly assigned to the intervention group with public health-oriented recreational cannabis access in pharmacies (regulated cannabis products, safer use information, voluntary counseling, no advertisement; 189/188) or the illegal market control group (continued illicit cannabis sourcing; 189/186).
Measurements: The primary outcome was self-reported severity of cannabis misuse after 6 months, as measured by the Cannabis Use Disorders Identification Test - Revised (range 0-32). Secondary outcomes involved depressive, anxiety, and psychotic symptoms, cannabis consumption amount, alcohol, and drug use.
Findings: Ten participants were not followed (2.7%). Primary analysis included those with complete data (182 vs. 182). There was some evidence of a difference in cannabis misuse between the legal cannabis intervention group (mean [M] = 10.1) and the illegal market control group (M = 10.9; β = -0.69, 95% confidence interval [CI] = -1.4 to 0.0, P = 0.052). These results were supported by an intention-to-treat multiple imputation analysis (n = 374). Additional sub-group analysis by whether the participant used other drugs or not suggested that any reduction in cannabis misuse was confined to those in the legal cannabis intervention group who used other drugs (PInteraction < 0.001). We found no statistically significant changes in any of the secondary outcomes.
Conclusions: Public health-oriented recreational cannabis access may decrease cannabis use and cannabis-related harms, especially among those using other drugs.
期刊介绍：
Addiction publishes peer-reviewed research reports on pharmacological and behavioural addictions, bringing together research conducted within many different disciplines.
Its goal is to serve international and interdisciplinary scientific and clinical communication, to strengthen links between science and policy, and to stimulate and enhance the quality of debate. We seek submissions that are not only technically competent but are also original and contain information or ideas of fresh interest to our international readership. We seek to serve low- and middle-income (LAMI) countries as well as more economically developed countries.
Addiction’s scope spans human experimental, epidemiological, social science, historical, clinical and policy research relating to addiction, primarily but not exclusively in the areas of psychoactive substance use and/or gambling. In addition to original research, the journal features editorials, commentaries, reviews, letters, and book reviews.
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