Effects of legal access versus illegal market cannabis on use and mental health: A randomized controlled trial.
Baltes-Flueckiger et al.·Addiction (Abingdon, England)Impact 3.3
GemischtGRADEModerat4 Zitate
Stichproben = 374 Pat.
Dauer6 Monate
KontrolleFortgesetzter Bezug über den illegalen Markt
EndpunktCUDIT-R
Verblindungoffen
DesignRCT
Cannabinoidvollspektrum
”Kernaussage
Schwache Evidenz für Reduktion von Cannabis-Missbrauch in der legalen Gruppe (10,1 vs. 10,9; p=0,052), aber keine statistisch signifikanten Effekte auf sekundäre Outcomes (Depression, Angst, psychotische Symptome).
Zusammenfassung
n=374 erwachsene Cannabis-Nutzende (Schweiz), randomisiert zu legalisiertem Apotheken-Zugang vs. illegaler Markt (6-Monate-Follow-up); Interventionsgruppe zeigte Tendenz zu niedrigerem CUDIT-R-Score (M=10.1 vs. 10.9, β=-0.69, 95% CI [-1.4 bis 0.0], p=0.052); Subgruppen-Analyse: signifikante Reduktion nur bei Nutzenden mit Polysubstanzgebrauch (p<0.001); keine signifikanten Unterschiede bei Depression, Angst, psychotischen Symptomen oder Konsummenge.
P
PopulationErwachsene Cannabiskonsumenten in Basel-Stadt, Schweiz, n=374 (randomisiert n=378, ausgewertet n=374)
I
InterventionRegulierter Cannabiszugang über Apotheken mit öffentlich-gesundheitlichen Maßnahmen (regulierte Produkte, Safer-Use-Information, freiwillige Beratung, kein Marketing)
C
KontrolleFortgesetzter Bezug über den illegalen Markt (Kontrollgruppe)
O
OutcomeCannabis-Missbrauch (CUDIT-R) nach 6 Monaten: Interventionsgruppe M=10,1 vs. Kontrollgruppe M=10,9 (β=−0,69, 95%-KI −1,4 bis 0,0, p=0,052); Subgruppenanalyse zeigt signifikante Reduktion nur bei gleichzeitigem anderen Drogenkonsum (p-Interaktion <0,001); keine signifikanten Unterschiede bei sekundären Outcomes.
Vertrauen in die Evidenz
Sehr niedrigNiedrigModeratHoch
Moderat
Dritte von vier GRADE-Stufen, die Effektschätzung ist wahrscheinlich verlässlich.
Herabgestuft wegen
Verzerrungsrisiko
Qualitätsprofil
Größe★★★★★
VerblindungOffen
EffektstärkeGemischt
Zitate / Jahr★★★★★
Autoren
Baltes-Flueckiger L, Steinauer R, Meyer M, Guessoum A, Herrmann O, Mosandl CF, Kronschnabel J, Pichler EM, Vogel M, Walter M
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; beta = -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 (P(Interaction) < 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.