Contingency management is associated with positive changes in attitudes and reductions in cannabis use even after discontinuation of incentives among non-treatment seeking youth.

BACKGROUND: It is important to identify interventions that reduce harm in youth not motivated to change their cannabis use. This study evaluated how short-duration contingency management (CM) impacts cannabis use attitudes and behavior after abstinence incentives are discontinued among non-treatment seeking youth. METHODS: Participants (N=220) were randomized to 4 weeks of abstinence-based CM (CB-Abst; n=126) or monitoring (CB-Mon; n=94). Participants completed self-report and provided biochemical measures of cannabis exposure at baseline, end-of-intervention, and 4-week follow-up. Changes in self-reported cannabis use frequency (days/week; times/week) and biochemically verified creatinine-adjusted 11-nor-9-carboxy-tetrahydrocannabinol concentrations (CN-THCCOOH) were analyzed between groups from baseline to follow-up. In CB-Abst, cannabis use goals at end-of-intervention were described and changes in cannabis use at follow-up were explored by goals and cannabis use disorder (CUD) diagnosis. RESULTS: There was a group by visit interaction on cannabis use (days: beta=0.93, p=0.005; times: beta=0.71, p<0.001; CN-THCCOOH: beta=0.26, p=0.004), with reductions at follow-up detected only in CB-Abst. Following 4 weeks of abstinence, 68.4% of CB-Abst participants wanted to reduce or abstain from cannabis use following completion of CM. Those in CB-Abst who set end-of-intervention reduction goals and were without CUD had greater decreases in cannabis use frequency at follow-up (Goals*time on days/week: beta=-2.27, p<0.001; CUD*time on times/week: beta=0.48, SE=0.24, t=2.01, p=0.048). CONCLUSIONS: Findings support the utility of brief incentivized abstinence for generating motivation to reduce cannabis use and behavior change even after incentives end. This study supports CM as a potentially viable harm reduction strategy for those not yet ready to quit.

Alcohol substitution during one month of cannabis abstinence among non-treatment seeking youth.

OBJECTIVE: Cannabis and alcohol use are correlated behaviors among youth. It is not known whether discontinuation of cannabis use is associated with changes in alcohol use. This study assessed alcohol use in youth before, during, and after 4 weeks of paid cannabis abstinence. METHODS: Healthy, non-treatment seeking, cannabis users (n = 160), aged 14-25 years, 84% of whom used alcohol in the last month, were enrolled for a 4-week study with a 2-4 week follow-up. Participants were randomly assigned to 4 weeks of either biochemically-verified cannabis abstinence achieved through a contingency management framework (CB-Abst) or monitoring with no abstinence requirement (CB-Mon). Participants were assessed at baseline and approximately 4, 6, 10, 17, 24, and 31 days after enrollment. A follow-up visit with no cannabis abstinence requirement for CB-Abst was conducted after 2-4 weeks. RESULTS: Sixty percent of individuals assigned to the CB-Abst condition increased in frequency and quantity of alcohol consumption during the 4-week period of incentivized cannabis abstinence. As a whole, CB-Abst increased by a mean of 0.6 drinking days and 0.2 drinks per day in the initial week of abstinence (p's < 0.006). There was no evidence for further increases in drinking frequency or quantity during the 30-day abstinence period (p's > 0.53). There was no change in drinking frequency or quantity during the 4-week monitoring or follow-up periods among CB-Mon. CONCLUSIONS: On average, 4 weeks of incentivized (i.e., paid) cannabis abstinence among non-treatment seeking youth was associated with increased frequency and amount of alcohol use in week 1 that was sustained over 4 weeks and resolved with resumption of cannabis use. However, there was notable variability in individual-level response, with 60% increasing in alcohol use and 23% actually decreasing in alcohol use during cannabis abstinence. Findings suggest that increased alcohol use during cannabis abstinence among youth merits further study to determine whether this behavior occurs among treatment seeking youth and its clinical significance.

Suggestibility is associated with alcohol self-administration, subjective alcohol effects, and self-reported drinking behavior.

BACKGROUND: Suggestibility, defined as an individual's inclination to accept and internalize messages, has not been studied in relation to alcohol use. Peer conformity, a component of suggestibility, may be related to alcohol use, as peer groups show similarities in patterns of alcohol use. Few studies have assessed how suggestibility and peer conformity relate to alcohol self-administration or to reinforcing effects of alcohol. AIMS: This study assessed whether suggestibility and peer conformity were associated with drinking behavior, alcohol self-administration, subjective response to alcohol, and drinking motives and expectancies. METHODS: Study 1 participants were alcohol drinkers (n=20), who completed a laboratory study of free-access intravenous alcohol self-administration. Study 2 participants were adolescents and young adults, age 14-25 (n=150), with lifetime alcohol use. Participants completed surveys of suggestibility and drinking patterns (Study 1 and 2), subjective alcohol effects (Study 1 only), and alcohol motives and expectancies (Study 2 only). RESULTS/OUTCOMES: In Study 1, participants with higher levels of suggestiblity self-administered more alcohol, and reported greater subjective alcohol effects. Peer conformity, though correlated with suggestibility, was not related to these measures. In Study 2, participants with higher suggestiblity reported more alcohol consumption, higher drinking motives and alcohol expectancies. Peer conformity was not related to alcohol consumption, but was related to coping and enhancement drinking motives, and all expectancies measures. CONCLUSIONS/INTERPRETATION: Results indicate that suggestibility, beyond peer conformity, may be a critical factor to study when examining alcohol consumption behavior, and may provide insight into the development of alcohol use disorder.