Do traumatic events and substance use co-occur during adolescence? Testing three causal etiologic hypotheses.

BACKGROUND: Why do potentially traumatic events (PTEs) and substance use (SU) so commonly co-occur during adolescence? Causal hypotheses developed from the study of posttraumatic stress disorder (PTSD) and substance use disorder (SUD) among adults have not yet been subject to rigorous theoretical analysis or empirical tests among adolescents with the precursors to these disorders: PTEs and SU. Establishing causality demands accounting for various factors (e.g. genetics, parent education, race/ethnicity) that distinguish youth endorsing PTEs and SU from those who do not, a step often overlooked in previous research. METHODS: We leveraged nationwide data from a sociodemographically diverse sample of youth (N = 11,468) in the Adolescent Brain and Cognitive Development Study. PTEs and substance use prevalence were assessed annually. To account for the many pre-existing differences between youth with and without PTE/SU (i.e. confounding bias) and provide rigorous tests of causal hypotheses, we linked within-person changes in PTEs and SU (alcohol, cannabis, nicotine) across repeated measurements and adjusted for time-varying factors (e.g. age, internalizing symptoms, externalizing symptoms, and friends' use of substances). RESULTS: Before adjusting for confounding using within-person modeling, PTEs and SU exhibited significant concurrent associations (ßs = .46-1.26, ps < .05) and PTEs prospectively predicted greater SU (ßs = .55-1.43, ps < .05) but not vice versa. After adjustment for confounding, the PTEs exhibited significant concurrent associations for alcohol (ßs = .14-.23, ps < .05) and nicotine (ßs = .16, ps < .05) but not cannabis (ßs = -.01, ps > .05) and PTEs prospectively predicted greater SU (ßs = .28-.55, ps > .05) but not vice versa. CONCLUSIONS: When tested rigorously in a nationwide sample of adolescents, we find support for a model in which PTEs are followed by SU but not for a model in which SU is followed by PTEs. Explanations for why PTSD and SUD co-occur in adults may need further theoretical analysis and adaptation before extension to adolescents.

The independent and combined impact of moral injury and moral distress on post-traumatic stress disorder symptoms among healthcare workers during the COVID-19 pandemic.

Background: Healthcare workers (HCWs) across the globe have reported symptoms of Post-Traumatic Stress Disorder (PTSD) during the COVID-19 pandemic. Moral Injury (MI) has been associated with PTSD in military populations, but is not well studied in healthcare contexts. Moral Distress (MD), a related concept, may enhance understandings of MI and its relation to PTSD among HCWs. This study examined the independent and combined impact of MI and MD on PTSD symptoms in Canadian HCWs during the pandemic.Methods: HCWs participated in an online survey between February and December 2021, with questions regarding sociodemographics, mental health and trauma history (e.g. MI, MD, PTSD, dissociation, depression, anxiety, stress, childhood adversity). Structural equation modelling was used to analyze the independent and combined impact of MI and MD on PTSD symptoms (including dissociation) among the sample when controlling for sex, age, depression, anxiety, stress, and childhood adversity.Results: A structural equation model independently regressing both MI and MD onto PTSD accounted for 74.4% of the variance in PTSD symptoms. Here, MI was strongly and significantly associated with PTSD symptoms (ß = .412, p < .0001) to a higher degree than MD (ß = .187, p < .0001), after controlling for age, sex, depression, anxiety, stress and childhood adversity. A model regressing a combined MD and MI construct onto PTSD predicted approximately 87% of the variance in PTSD symptoms (r2 = .87, p < .0001), with MD/MI strongly and significantly associated with PTSD (ß = .813, p < .0001), after controlling for age, sex, depression, anxiety, stress, and childhood adversity.Conclusion: Our results support a relation between MI and PTSD among HCWs and suggest that a combined MD and MI construct is most strongly associated with PTSD symptoms. Further research is needed better understand the mechanisms through which MD/MI are associated with PTSD.

MI and MD were each independently associated with PTSD symptoms (including dissociation), when controlling for sex, age, childhood adversity, depression, anxiety and stress.Combining both MI and MD constructs into a single latent variable accounted for the greatest proportion of variance explained in PTSD symptoms among HCWs during the COVID-19 pandemic.Results suggest that expanding the construct of MI to include team and systemic organisational MD may be appropriate in the healthcare context.

How Does Parental Monitoring Reduce Adolescent Substance Use? Preliminary Tests of Two Potential Mechanisms.

OBJECTIVE: The purpose of this study was to test two non-exclusive mechanisms by which parental monitoring might reduce teen substance use. The first mechanism (M1) is that monitoring increases punishment for substance use since parents who monitor more are more likely to find out when substance use occurs. The second mechanism (M2) is that monitoring directly prevents/averts teens from using substances in the first place for fear that parents would find out. METHOD: A total of 4,503 teens ages 11-15 years old in 21 communities across the United States completed a survey reporting on parents' monitoring/knowledge and teens' substance use. RESULTS: We found no support for M1: Parents with greater parental monitoring were not more likely to be aware when the teen had used substances (odds ratios = 0.79-0.93, ps = .34-.85), so they could not have increased the rate of punishment. We found support for M2: When asked directly, teens identified instances in which they planned to or had a chance to use substances but did not because their parents got in the way or would have found out (p < .01). Had all those opportunities for substance use occurred rather than been averted by parents, the prevalence of substance use in the sample would have been 1.4 times higher. CONCLUSIONS: In this community-based sample of teens, we failed to support prior punishment-centric theories of how monitoring might reduce teen substance use. Rather, monitoring may directly discourage teens from using substances regardless of whether it increases parents' awareness of substance use or results in more punishment. Replication in other samples and contexts is needed.

Machine learning models predict PTSD severity and functional impairment: A personalized medicine approach for uncovering complex associations among heterogeneous symptom profiles.

OBJECTIVE: Posttraumatic stress disorder (PTSD) is a debilitating psychiatric illness, experienced by approximately 10% of the population. Heterogeneous presentations that include heightened dissociation, comorbid anxiety and depression, and emotion dysregulation contribute to the severity of PTSD, in turn, creating barriers to recovery. There is an urgent need to use data-driven approaches to better characterize complex psychiatric presentations with the aim of improving treatment outcomes. We sought to determine if machine learning models could predict PTSD-related illness in a real-world treatment-seeking population using self-report clinical data. METHOD: Secondary clinical data from 2017 to 2019 included pretreatment measures such as trauma-related symptoms, other mental health symptoms, functional impairment, and demographic information from adults admitted to an inpatient unit for PTSD in Canada (n = 393). We trained two nonlinear machine learning models (extremely randomized trees) to identify predictors of (a) PTSD symptom severity and (b) functional impairment. We assessed model performance based on predictions in novel subsets of patients. RESULTS: Approximately 43% of the variance in PTSD symptom severity (R²avg = .43, R²median = .44, p = .001) was predicted by symptoms of anxiety, dissociation, depression, negative trauma-related beliefs about others, and emotion dysregulation. In addition, 32% of the variance in functional impairment scores (R²avg = .32, R²median = .33, p = .001) was predicted by anxiety, PTSD symptom severity, cognitive dysfunction, dissociation, and depressive symptoms. CONCLUSIONS: Our results reinforce that dissociation, cooccurring anxiety and depressive symptoms, maladaptive trauma appraisals, cognitive dysfunction, and emotion dysregulation are critical targets for trauma-related interventions. Machine learning models can inform personalized medicine approaches to maximize trauma recovery in real-world inpatient populations. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Prospective associations between cannabis use and depressive symptoms across adolescence and early adulthood.

Cannabis use and occurrences of depression during adolescence are common. However, the temporal relationship between the two is less understood. Does depression lead to cannabis use, or does cannabis use lead to depression, or is it a combination of both? Furthermore, this directionality is confounded by other substance use, specifically binge drinking, which is common during adolescence. This study aimed to examine the temporal directionality of cannabis use and depression among a prospective, longitudinal, sequential cohort of 15 to 24-year-olds. Data were drawn from the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study. The final sample included 767 participants. Multilevel regression models were run to assess concurrent (at the same time point) and prospective (1 year later) associations between cannabis use and depression. When measured concurrently, depressive symptoms did not significantly predict past-month cannabis use but did significantly predict more days of use among cannabis users. Prospective associations indicated that depressive symptoms significantly predicted cannabis use 1 year later and cannabis use significantly predicted depressive symptoms 1 year later. We found no evidence that these associations varied by age or binge drinking. Overall, the relationship between cannabis use and depression appears to be complex and not unidirectional.

Pandemic-Related Changes in the Prevalence of Early Adolescent Alcohol and Drug Use, 2020-2021: Data From a Multisite Cohort Study.

PURPOSE: Evaluate changes in early adolescent substance use from May 2020 to May 2021 during the coronavirus disease 2019 pandemic using data from a prospective nationwide cohort: the Adolescent Brain Cognitive Development Study. METHODS: In 2018-2019, 9,270 youth aged 11.5-13.0 completed a prepandemic assessment of past-month alcohol and drug use, then up to seven during-pandemic assessments between May 2020 and May 2021. We compared the prevalence of substance use among same-age youth across these eight timepoints. RESULTS: Pandemic-related decreases in the past-month prevalence of alcohol use were detectable in May 2020, grew larger over time, and remained substantial in May 2021 (0.3% vs. 3.2% prepandemic, p <.001). Pandemic-related increases in inhalant use (p = .04) and prescription drug misuse (p < .001) were detectable in May 2020, shrunk over time, and were smaller but still detectable in May 2021(0.1%-0.2% vs. 0% pre-pandemic). Pandemic-related increases in nicotine use were detectable between May 2020 and March 2021 and no longer significantly different from prepandemic levels in May 2021 (0.5% vs. 0.2% prepandemic, p = .09). There was significant heterogeneity in pandemic-related change in substance use at some timepoints, with increased rates among youth identified as Black or Hispanic or in lower-income families versus stable or decreased rates among youth identified as White or in higher-income families. DISCUSSION: Among youth ages 11.5-13.0 years old, rates of alcohol use remained dramatically reduced in May 2021 relative to prepandemic and rates of prescription drug misuse and inhalant use remained modestly increased. Differences remained despite the partial restoration of prepandemic life, raising questions about whether youth who spent early adolescence under pandemic conditions may exhibit persistently different patterns of substance use.

Associations between trauma and substance use among healthcare workers and public safety personnel during the SARS-CoV-2 (COVID-19) pandemic: the mediating roles of dissociation and emotion dysregulation.

BACKGROUND: Given the highly stressful environment surrounding the SARS-CoV-2 pandemic, healthcare workers (HCW) and public safety personnel (PSP) are at an elevated risk for adverse psychological outcomes, including posttraumatic stress disorder (PTSD) and alcohol/substance use problems. As such, the study aimed to identify associations between PTSD severity, related dissociation and emotion dysregulation symptoms, and alcohol/substance use problems among HCWs and PSP. METHODS: A subset of data (N = 498; HCWs = 299; PSP = 199) was extracted from a larger study examining psychological variables among Canadian HCWs and PSP during the pandemic. Structural equation modelling assessed associations between PTSD symptoms and alcohol/substance use-related problems with dissociation and emotion dysregulation as mediators. RESULTS: Among HCWs, dissociation fully mediated the relation between PTSD and alcohol-related problems (indirect effect ß = .133, p = .03) and emotion dysregulation partially mediated the relation between PTSD and substance-related problems (indirect effect ß = .151, p = .046). In PSP, emotion dysregulation fully mediated the relation between PTSD and alcohol-related problems (indirect effects ß = .184, p = .005). For substance-related problems among PSP, neither emotion dysregulation nor dissociation (ps >.05) had any effects. CONCLUSION: To our knowledge, this is the first study examining associations between PTSD severity and alcohol/substance use-related problems via mediating impacts of emotion dysregulation and dissociation among HCWs and PSP during the SARS-CoV-2 pandemic. These findings highlight dissociation and emotion dysregulation as important therapeutic targets for structured interventions aimed at reducing the burden of PTSD and/or SUD among Canadian HCWs or PSP suffering from the adverse mental health impacts of the SARS-CoV-2 pandemic.

Among healthcare workers, dissociation mediated relation between posttraumatic stress disorder (PTSD) severity and alcohol-related problems and emotion dysregulation mediated relation between PTSD severity and substance-related problems.Among public safety personnel, emotion dysregulation mediated relation between PTSD severity and alcohol-related problems. Neither dissociation nor emotion dysregulation mediated relation between PTSD severity and substance-related problems.Results underscore dissociation and emotion dysregulation as potential key therapeutic targets for intervention for healthcare workers and public safety personnel struggling with PTSD and comorbid alcohol/substance use-related problems.

Income shock increases preferences for smaller immediate rewards and reduces alcohol demand among a sample of crowd-sourced adults.

In behavioral economics, income shock manipulations (hypothetical narratives where money is gained or lost) can provide meaningful insight into decision-making related to primary and secondary commodities. To date, few studies have examined the impact of income shock on delay discounting in healthy controls and individuals using substances, and no study to date has examined the impact of income shock on alcohol demand. This study examined the effects of income shock on behavioral economic assessments (i.e., delay discounting and alcohol demand) among a sample of adult participants recruited via Amazon Mechanical Turk (N = 140). The sample was predominantly middle-aged, male, and White (mean age = 38.81; 37.1% female; 77.1% White). Participants were randomly assigned to one of three income shock narratives (negative, neutral, positive). They completed two versions of the 5-choice delay discounting task for $100 and $1,000 and an alcohol purchase task (APT) before and after the income shock narrative. Following negative income shock, preferences for smaller immediate rewards increased in the $100 version of the discounting task and decreased the price at which alcohol consumption was suppressed to zero (i.e., break point). Sensitivity to price changes in the APT decreased following neutral and positive income shock but not the negative condition. Results replicate and extend prior findings examining the impact of income shock on delay discounting. Furthermore, this is the first study to study income shock effects on alcohol demand. Findings suggest that primary commodity manipulation (i.e., money) can potentially impact decision-making regarding secondary commodities (i.e., alcohol). (PsycInfo Database Record (c) 2023 APA, all rights reserved).

The Effects of a Single Transcranial Direct Current Stimulation Session on Impulsivity and Risk Among a Sample of Adult Recreational Cannabis Users.

Individuals with substance use disorders exhibit risk-taking behaviors, potentially leading to negative consequences and difficulty maintaining recovery. Non-invasive brain stimulation techniques such as transcranial direct current stimulation (tDCS) have yielded mixed effects on risk-taking among healthy controls. Given the importance of risk-taking behaviors among substance-using samples, this study aimed to examine the effects of tDCS on risk-taking among a sample of adults using cannabis. Using a double-blind design, 27 cannabis users [M(SD) age = 32.48 (1.99), 41% female] were randomized, receiving one session of active or sham tDCS over the bilateral dorsolateral prefrontal cortex (dlPFC). Stimulation parameters closely followed prior studies with anodal right dlPFC and cathodal left dlPFC stimulation. Risk-taking-assessed via a modified Cambridge Gambling Task-was measured before and during tDCS. Delay and probability discounting tasks were assessed before and after stimulation. No significant effects of stimulation on risk-taking behavior were found. However, participants chose the less risky option ∼86% of the trials before stimulation which potentially contributed to ceiling effects. These results contradict one prior study showing increased risk-taking among cannabis users following tDCS. There was a significant increase in delay discounting of a $1000 delayed reward during stimulation for the sham group only, but no significant effects for probability discounting. The current study adds to conflicting and inconclusive literature on tDCS and cognition among substance-using samples. In conclusion, results suggest the ineffectiveness of single session dlPFC tDCS using an established stimulation protocol on risk-taking, although ceiling effects at baseline may have also prevented behavior change following tDCS.

Dissociative symptomatology mediates the relation between posttraumatic stress disorder severity and alcohol-related problems.

BACKGROUND: Up to 50% of individuals with posttraumatic stress disorder (PTSD) endorse problematic alcohol use. Typically, these individuals present with more complex and often more severe PTSD symptoms than those who do not report problematic alcohol use. Emerging literature suggests that heightened symptoms of dissociation are likewise associated with greater PTSD symptom severity. Despite this knowledge, the role of dissociation in the relation between PTSD severity and alcohol-related problems has yet to be examined. Here, we explore the mediating role of dissociative symptomatology on the association between PTSD severity and alcohol-related problems within a PTSD treatment-seeking sample. METHODS: Structural equation modeling was used to test the mediating role of dissociative symptomatology between PTSD severity and alcohol-related problems. Participants [N = 334; mean age (SD) = 44.29 (9.77), 50% female] were drawn from a clinical intake battery database for PTSD in-patient treatment services at Homewood Health Care, Guelph, ON, Canada. A subset of battery measures assessing PTSD severity, dissociative symptomatology, and alcohol-related problems were submitted to analysis. RESULTS: A significant positive association emerged between PTSD severity and alcohol-related problems (ß = 0.127, p < 0.05) in the absence of dissociative symptomatology. Critically, however, when added to this model, dissociative symptomatology (six unique facets of dissociation assessed by the Multiscale Dissociation Inventory) mediated the relation between PTSD severity and alcohol-related problems. Specifically, greater PTSD severity was associated with greater dissociative symptomatology (ß = 0.566, p < 0.0001), which was in turn associated with greater alcohol-related problems (ß = 0.184, p < 0.05). CONCLUSIONS: These results suggest that dissociative symptomatology plays a key role in explaining the relation between PTSD severity and alcohol-related problems. Future studies should examine the impact of targeting dissociative symptomatology specifically in treating individuals with PTSD who endorse alcohol-related problems.

Posttraumatic Stress Disorder Symptomatology and Substance Use in an Outpatient Concurrent Disorders Sample.

OBJECTIVE: Posttraumatic stress disorder (PTSD) and substance use disorders (SUDs) present a complex and often severe clinical presentation within a concurrent disorders context. The objective of this study was to examine associations between PTSD symptoms and SUD outcomes to better understand the clinical phenomenon of comorbid PTSD and SUD. Multivariate statistical methods were used to test the hypothesis that elevated PTSD symptoms, both at the level of global severity and specific PTSD symptom clusters, are associated with greater substance use and related problems. METHODS: Data were collected from an intake assessment battery within a specialized concurrent disorders outpatient service in Hamilton, ON. The sample comprised 326 participants (mean age = 37.19, 45.4% female). Structural equation models examined associations between PTSD and alcohol, cannabis, and substance use frequency and problems, controlling for age and sex. Alcohol was ultimately dropped from the model due to non-significant bivariate associations. RESULTS: Higher global PTSD symptomatology was significantly associated with higher cannabis and other substance use frequency and related problems. Analyses using PTSD cluster scores showed higher scores for alterations in arousal were positively associated with cannabis-related problems, drug-related problems, and cannabis and other substance use frequency. Avoidance was significantly associated with cannabis frequency and cannabis-related problems. In general, effect sizes were small in magnitude, accounting for between 9% and 25% of variance. CONCLUSION: Significant cluster-level associations indicate the importance of specific PTSD symptoms (hyperarousal, avoidance) in relation to substance use when identifying therapeutic targets among individuals presenting with comorbid PTSD-SUD. This multivariate approach provides a higher resolution and potentially more clinically informative representation of the complex clinical presentation of PTSD and SUD in a concurrent disorder population and could guide the development of more effective treatment paths.

Acute and extended exposure to episodic future thinking in a treatment seeking addiction sample: A pilot study.

Individuals with addictive disorders commonly exhibit a shortened temporal window (shortened period of time an individual can imagine into their own future), which interferes with treatment focusing on long-term sobriety or reductions in use. Episodic future thinking (EFT) involves generating personalized cues related to anticipated, positive future events. EFT has been shown to reduce impulsive decision-making and the reinforcing value of addictive substances; however, this has only been shown in nontreatment samples. The current study examined the feasibility and impact of a 1-week EFT protocol on decision-making and alcohol motivation in a sample of individuals receiving treatment for alcohol use disorder. We randomly assigned twenty-eight individuals currently enrolled in community-based alcohol use disorder treatment to either an EFT protocol or a control episodic recent thinking (ERT) protocol. Participants completed assessments of delay discounting, alcohol demand, craving, self-efficacy, consideration of consequences, and mindfulness at baseline, after 1 week of EFT practice, and at 1-week follow-up. We observed patterns of reductions in alcohol demand indices, delay discounting rates, and an increase in mindfulness after both acute (1 session) and extended (4 sessions) exposure to EFT. These proof-of-concept findings lay the foundation for a randomized controlled trial of EFT as a supplement to addictions treatment.

Discounting of delayed monetary and cannabis rewards in a crowdsourced sample of adults.

Excessive delayed reward discounting (DD) is observed across many addictive disorders. However, research on DD among cannabis users is limited, with even less research on discounting of cannabis rewards. This study examined monetary and cannabis reward discounting among cannabis and noncannabis users. A large sample of adults (N = 2,857) recruited from an online crowdsourcing platform was assessed on demographics and DD of monetary ($10, $100) and cannabis (10 g) rewards. Analyses of variance were used to evaluate magnitude and commodity effects. Hierarchical multiple regression models were run to assess whether cannabis use frequency was associated with discounting rates for monetary and cannabis rewards. A magnitude effect was found for the monetary rewards where $10 was discounted more steeply compared to $100 (p < .0001). A commodity effect was found where discounting was higher for the 10g cannabis reward compared to monetary rewards (ps < .05). Regression models controlling for demographics and other substance use indicated severity of cannabis problems significantly predicted discounting of $100 (ß = .045, p < .05) and 10 g of cannabis (ß = .088, p < .05). Cannabis use frequency was not significantly associated with any DD measures after controlling for other substance use (ps > .05). These results suggest the association between cannabis use and DD is complex and generally small in magnitude. This study adds to the literature on DD and cannabis use and suggests the need for further studies to determine the extent to which cannabis use impacts DD, both chronically and acutely. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Delay Discounting as a Transdiagnostic Process in Psychiatric Disorders: A Meta-analysis.

Importance: Delay discounting is a behavioral economic index of impulsive preferences for smaller-immediate or larger-delayed rewards that is argued to be a transdiagnostic process across health conditions. Studies suggest some psychiatric disorders are associated with differences in discounting compared with controls, but null findings have also been reported. Objective: To conduct a meta-analysis of the published literature on delay discounting in people with psychiatric disorders. Data Sources: PubMed, MEDLINE, PsycInfo, Embase, and Web of Science databases were searched through December 10, 2018. The psychiatric keywords used were based on DSM-IV or DSM-5 diagnostic categories. Collected data were analyzed from December 10, 2018, through June 1, 2019. Study Selection: Following a preregistered Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) protocol, 2 independent raters reviewed titles, abstracts, and full-text articles. English-language articles comparing monetary delay discounting between participants with psychiatric disorders and controls were included. Data Extraction and Synthesis: Hedges g effect sizes were computed and random-effects models were used for all analyses. Heterogeneity statistics, one-study-removed analyses, and publication bias indices were also examined. Main Outcomes and Measures: Categorical comparisons of delay discounting between a psychiatric group and a control group. Results: The sample included 57 effect sizes from 43 studies across 8 diagnostic categories. Significantly steeper discounting for individuals with a psychiatric disorder compared with controls was observed for major depressive disorder (Hedges g = 0.37; P = .002; k = 7), schizophrenia (Hedges g = 0.46; P = .004; k = 12), borderline personality disorder (Hedges g = 0.60; P < .001; k = 8), bipolar disorder (Hedges g = 0.68; P < .001; k = 4), bulimia nervosa (Hedges g = 0.41; P = .001; k = 4), and binge-eating disorder (Hedges g = 0.34; P = .001; k = 7). In contrast, anorexia nervosa exhibited statistically significantly shallower discounting (Hedges g = -0.30; P < .001; k = 10). Modest evidence of publication bias was indicated by a statistically significant Egger test for schizophrenia and at the aggregate level across studies. Conclusions and Relevance: Results of this study appear to provide empirical support for delay discounting as a transdiagnostic process across most of the psychiatric disorders examined; the literature search also revealed limited studies in some disorders, notably posttraumatic stress disorder, which is a priority area for research.

Elevated cannabis demand is associated with driving after cannabis use in a crowd-sourced sample of adults.

Epidemiological and roadside studies suggest that driving after cannabis use (DACU) is prevalent in the United States, and rates have increased following legalization or decriminalization of cannabis in some U.S. states. Reinforcing value of addictive substances (as measured by behavioral economic demand tasks), is an emerging risk factor for driving under the influence. This study sought to expand upon the previously documented link between alcohol demand and driving after drinking by examining whether similar associations exist between cannabis demand and DACU. A large diverse sample of adults (N = 733) recruited via an online crowd-sourcing platform (Amazon Mechanical Turk) competed a validated marijuana purchase task assessing cannabis consumption across a range of prices and validated assessments of DACU, cannabis misuse, and demographics. In analyses of covariance controlling for age, sex, income, and level of cannabis misuse, individuals who endorsed DACU showed elevated cannabis demand across all demand indices examined (ps < .05). Logistic regression indicated that increased intensity of demand was uniquely associated with a greater likelihood of DACU (odds ratio [OR] = 1.61-2.02, ps < .03). Breakpoint, maximum expenditure, and price point corresponding to maximum expenditure uniquely predicted DACU in separate models (OR = 1.41-1.68, ps < .03) but not in a combined model (ORs < 1.36, ps > .47). These results provide initial evidence that elevated cannabis demand may be a distal risk factor for DACU, but future research is needed to clarify the specific relationship between cannabis demand and DACU. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Elevated Behavioral Economic Demand for Alcohol in Co-Users of Alcohol and Cannabis.

OBJECTIVE: Co-use of cannabis and alcohol is associated with increased drinking and other negative consequences relative to use of alcohol alone. One potential explanation for these differences is overvaluation of alcohol (e.g., alcohol demand) among co-users, similar to established overvaluation of alcohol among tobacco and alcohol co-users. This study examined differences in alcohol demand between an alcohol and cannabis co-user group and an alcohol-only group. METHOD: A large sample of adult drinkers (n = 1,643, 54% female) was recruited through an online crowdsourcing site (Amazon Mechanical Turk). Of the full sample, 476 participants reported weekly or greater cannabis use in the past 6 months (co-user group); 888 reported never using cannabis in the past 6 months (alcohol-only group). Assessments included a validated alcohol purchase task and self-report measures of alcohol and cannabis use. RESULTS: Co-users reported significantly higher alcohol consumption across the elastic portion of the alcohol demand curve (i.e., $1.50-$9.00/drink). Analyses of covariance controlling for alcohol use and demographics revealed significantly higher breakpoint (p = .025) and Omax (p = .002) and significantly lower elasticity (p < .003) in the co-user group. Intensity and Pmax did not significantly differ between groups. CONCLUSIONS: Co-users of cannabis and alcohol overvalue alcohol compared with individuals who drink alcohol but do not use cannabis. This study is generally consistent with prior studies on alcohol and tobacco co-users, providing converging evidence that polysubstance use is associated with overvaluation of alcohol. These findings have important implications for treatment and prevention, particularly in the context of changes in cannabis legalization.