Cannabis use during treatment for alcohol use disorders predicts alcohol treatment outcomes

Cannabis use and alcohol and drug outcomes in a longitudinal sample of sober living house residents in California

INTRODUCTION

Some evidence suggests that cannabis may be a safer substitute for other drugs. Historically, sober living houses (SLHs) have been abstinence-based environments designed for individuals in recovery to live with others in recovery. However, the evolving legal landscape around cannabis use has left SLH operators and managers in a difficult position regarding policies related to cannabis use among residents. The primary aim of this study was to examine how cannabis use relates to alcohol use, other drug use, and related problems among SLH residents.

METHODS

Baseline (N = 557), 6-month (n = 462), and 12-month (n = 457) data came from SLH residents living in 48 houses in Los Angeles, CA from 2018 to 2021. Longitudinal generalized estimating equation models tested associations between any past six-month cannabis use and alcohol and non-cannabis drug outcomes: any use, number of days of use, and any alcohol- or drug-related problems. Final models adjusted for baseline age, sex, race-and-ethnicity, inpatient substance use treatment, and alcohol/drug use days, and time-varying 12-step attendance and percent of social network using drugs/alcohol heavily.

RESULTS

At baseline, 107 (19.2 %) residents reported cannabis use in the past six months. At 12 months, 80 (17.5 %) residents reported cannabis use in the past six months. Across all timepoints, any vs. no past six-month cannabis use was related to significantly (P < 0.05) higher odds of past-month alcohol use (OR = 3.85, 95 % CI: 2.65, 5.59); more drinking days in the past six months (IRR = 1.76, 95 % CI: 1.40, 2.21); higher odds of alcohol problems (OR = 2.74, 95 % CI: 1.99, 3.76); higher odds of past-month drug use (OR = 10.41, 95 % CI: 6.37, 17.00); more drug use days in the past six months (IRR = 1.86, 95 % CI: 1.40, 2.49); and higher odds of drug problems (OR = 14.99, 95 % CI: 9.91, 22.68).

CONCLUSIONS

During each assessment period, almost one-fifth of individuals residing in sample of California sober living houses report using cannabis in the past six months. Cannabis does not appear to work as a substitute for alcohol or other drugs in this population because cannabis use is related to increased risk of alcohol and other drug use and problems. SLH managers and operators should consider potential harm that could result from house policies that fail to address cannabis use.

Cannabis donation as a harm reduction strategy: a case study

BACKGROUND

The United States (US) continues to experience unprecedented rates of overdose mortality and there is increased need to identify effective harm reduction practices. Research from Canada describes cannabis donation through harm reduction agencies as an adjunctive strategy to mitigate the negative consequences of more harmful drugs. This case study describes the operational logistics, feasibility, and potential benefits of a cannabis donation program that was operated through a harm reduction program in rural Michigan.

CASE PRESENTATION

We applied a community driven research approach to gather information from harm reduction program staff about the implementation and evolution of cannabis donation efforts in Michigan. We also examined 20-months (September 2021 through May 2023) of administrative data from a cannabis company to compare the sale and donation of cannabis products. Ten cannabis-experienced harm reduction clients received cannabis donations, with clinical staff determining client interest and appropriateness, and providing weekly pick-up or delivery. To expand product availability and sustainability, we examined administrative data from a commercialcannabis company that volunteered to provide donations. This administrative data suggests that while flower products constitute most of the adult and medical sales, edible, oil, and topical products predominated donations. Further, cost analysis suggests that donations represent only 1% of total gross sales and account for much less than the expected yearly donation amount.

CONCLUSIONS

Research suggests there is potential to reduce alcohol and drug use related harms of more dangerous substances through substitution with cannabis. This case study is the first to document cannabis donation as a harm reduction practice in the US and suggests potential for sustainability dependent on state laws. Findings from this case study provide a starting point for inquiry into cannabis donation as a harm reduction strategy in the US; future research is needed to fully understand the individual-level outcomes, public health impacts, necessary legal regulations, and best practices for cannabis donation programs through harm reduction organizations.

Simultaneous Cannabis and Alcohol Use among Medical Cannabis Patients

Background: During the past two decades of cannabis legalization, the prevalence of medical cannabis (MC) use has increased and there has also been an upward trend in alcohol consumption. As less restricted cannabis laws generate more adult cannabis users, there is concern that more individuals may be simultaneously using medical cannabis with alcohol. A few studies have examined simultaneous use of medical cannabis with alcohol, but none of those studies also assessed patients' current or previous non-medical cannabis use. This paper explores simultaneous alcohol and medical cannabis use among medical cannabis patients with a specific focus on previous history of cannabis use and current non-medical cannabis use. Methods: A retrospective cohort study of MC patients (N = 319) from four dispensaries located in New York. Bivariate chi-square tests and multivariable logistic regression are used to estimate the extent to which sociodemographic and other factors were associated with simultaneous use. Results: Approximately 29% of the sample engaged in simultaneous use and a large share of these users report previous (44%) or current (66%) use of cannabis for non-medical purposes. MC patients who either previously or currently use cannabis non-medicinally, men, and patients using MC to treat a pain-related condition, were significantly more likely to report simultaneous alcohol/MC use. Conclusions: Findings indicate that there may be differential risks related to alcohol/MC use, which should be considered by cannabis regulatory policies and prevention/treatment programs. If patients are using cannabis and/or alcohol to manage pain, clinicians should screen for both alcohol and cannabis use risk factors.

Alcohol and cannabis dual use among Black adults: Associations with alcohol use, use-related problems, and race-based discrimination

BACKGROUND AND OBJECTIVES

Black adults who drink alcohol appear at risk for poor alcohol-related outcomes, yet little research has examined whether cannabis use among those who consume alcohol (alcohol-cannabis dual use) is related to worse alcohol-related consequences, as observed in predominantly White samples. Further, it may be that experiencing more race-based discrimination may be related to using multiple substances to cope with such experiences; however, no known studies have examined the impact of race-based discrimination on alcohol-cannabis dual use.

METHODS

Participants were 270 Black undergraduates who endorsed past-month drinking, 112 of whom endorsed alcohol-cannabis dual use.

RESULTS

The dual use group reported heavier drinking, more drinking-related problems, and more race-based microaggressions (but not overt racism) than the alcohol-only group.

CONCLUSIONS

The use of cannabis among Black young adults who drink alcohol was related to heavier drinking and more alcohol-related problems. Further, experiencing more microaggressions may place these individuals at risk for using multiple substances, presumably to cope with these experiences.

SCIENTIFIC SIGNIFICANCE

Considering models suggesting that the dual use of cannabis may result in less alcohol use, the current study highlights that for Black adults who consume alcohol, cannabis dual use is related to heavier drinking and more alcohol-related problems, which can inform intervention and treatment efforts.

The role of sex in daily levels of high-risk alcohol and cannabis co-use

Background

Co-use of alcohol and cannabis is highly prevalent and may be associated with negative outcomes. The intersection between alcohol and cannabis use remains poorly understood. The present study assessed this intersection and the moderating effects of sex on the daily levels of high-risk alcohol and cannabis co-use.

Methods

A secondary analysis of an experimental pharmacology study specifically designed to recruit individuals using both alcohol and cannabis was conducted. Thirty-three non-treatment seeking subjects (19 M/14F) reporting high-risk levels of alcohol and cannabis use completed a 30-day Timeline Follow-back (TLFB) assessment for alcohol and cannabis use, resulting in a total of N = 990 observations. Logistic models tested the probability of same day cannabis use as predicted by alcohol use (any use, total drinking, and binge drinking), sex, and alcohol use by sex interactions.

Results

Drinking any alcohol on a given day was associated with a significant increase in the likelihood of same-day cannabis use (b = 0.61, p = 0.001) as was amount of alcohol consumed on a given day (b = 0.083, p = 0.012). These relations were significantly moderated by sex (b = 1.58, p<0.001; b = 0.14, p = 0.044). Male-identifying individuals demonstrated an increased probability of concurrent cannabis use with any alcohol use on a given day, and this relationship increased linearly as the number of drinks consumed increased.

Conclusions

The present study investigated the patterns associated with co-using alcohol and cannabis in individuals reporting high-risk levels of both alcohol and cannabis use. The sex-dependent findings suggest that males are at higher risk for co-using alcohol and cannabis compared with females.

Phencyclidine Positivity on Urine Drug Screening in Patients Treated for Alcohol Withdrawal on a Dual-diagnosis Medically Assisted Withdrawal Unit

OBJECTIVES

Little contemporary research has explored phencyclidine (PCP) use in people with alcohol use disorder. Therefore, we sought to determine the prevalence of PCP positivity on urine toxicology screening among patients admitted for alcohol withdrawal, identify correlates of PCP positivity, and investigate PCP positivity's relationship to length of stay (LOS) and risk of facility readmission.

METHODS

This was a retrospective study of patients admitted to a dual-diagnosis medically assisted withdrawal unit for alcohol withdrawal from 2014 to 2019. Univariate tests and logistic regression were used to investigate potential correlates of PCP positivity on admission toxicology screening (primary outcome). Multivariable linear regression models and survival analyses analyzing LOS and risk of readmission (secondary outcomes) were also developed.

RESULTS

Ninety of 3731 patients (2.4%) screened positive for PCP. There were significant associations on univariate testing between PCP positivity and age, race, homeless status, and urine toxicology positivity for amphetamines, benzodiazepines, barbiturates, cocaine, tetrahydrocannabinol, and oxycodone. On multivariate logistic regression, only tetrahydrocannabinol, barbiturates, and cocaine positivity were associated with PCP positivity. Multivariate logistic regression and survival analysis found no statistically significant associations between PCP positivity and LOS or risk of readmission.

CONCLUSIONS

This study provides rare analysis of contemporary data on PCP use among patients undergoing medically assisted alcohol withdrawal. Phencyclidine positivity was uncommon, but use appears considerably higher among this patient population than the general population. There was no significant association between PCP positivity and LOS or readmission risk.

Risky drinking and other drug use in adults with chronic conditions in the United States: differential associations by race/ethnicity

Co-use of multiple drugs may prolong or increase heavy drinking, even for individuals with health conditions adversely affected by it. Patterns of alcohol and drug use may vary across racial/ethnic groups, with differential implications for health. This study examines racial/ethnic differences in the associations between risky drinking and other drug use in adults with diabetes, hypertension, heart disease, or cancer. Multiple logistic regression modeling, stratified by condition, was performed using a nationally representative sample of adults drawn from the 2015 to 2019 National Survey on Drug and Health. The outcome was risky drinking (consuming more than 7/14 drinks weekly). Other drugs considered were tobacco, marijuana, illicit drugs, and non-medical prescription drugs. Covariates included age, sex, education, income, marital/cohabitation status, health insurance coverage, and self-rated health status. Each drug category was positively associated with risky drinking across all four conditions. Racial/ethnic minority adults were less likely than White adults to engage in risky drinking, with this pattern most consistent for those with hypertension. Other drug use in minority adults (i.e. tobacco and illicit drug use in Black and Hispanic adults, and marijuana and prescription drug use in Asian adults) was associated with disproportionately greater odds of risky drinking compared with White adults. This pattern was more prominent for those with a heart condition, and not found for those with cancer. Future interventions might address co-use of alcohol and other drugs in adults with chronic conditions, with special attention to racial/ethnic minority adults.

Cannabis use in repeated representative cross-sectional studies on Italian adults after the COVID-19 pandemic

Lockdown measures in response to the COVID-19 pandemic in 2020 yielded dramatic changes in drug consumption. A cross-sectional study was conducted on a representative sample of 6003 Italian adults (18-74 years) in April-May 2020 - reporting information before lockdown and at the time of interview - and two years later (i.e., in February-March 2022). Italian adults using cannabis decreased from 7.0% in pre-pandemic to 5.9% during lockdown (percent change -15.7%) and to 6.7% in 2022 (-4.3%). The reduction was particularly evident among adults aged 55-74 years, whereas cannabis use strongly increased among those aged 18-34 years. In the last period considered (2022), cannabis use was significantly more frequent in men (adjusted odds ratio, OR = 1.43), adults aged 18-34 years (p-trend <0.001), individuals with a low or high level of education (OR = 1.42 and 1.46, respectively), those from Central or Southern Italy/islands (OR = 1.50 and 1.38, respectively), and those with an economic status above the average (OR = 3.07). In 2022, cannabis use was also more frequently reported in current smokers (OR = 3.52), current e-cigarette and heated tobacco product users (OR = 6.09 and 2.94, respectively), individuals with a risky alcohol consumption (OR = 4.60), gamblers (OR = 3.76), those with anxiety and depression (OR = 2.50 and 2.80, respectively), those using psychotropic drugs (OR = 8.96), those with a low quality of life (OR = 1.91), and those sleeping less (OR = 1.42). After the COVID-19 pandemic, cannabis use was more frequent in individuals with other addictive behaviours, and with anxiety and depressive symptoms.

Past year high-intensity drinking moderates the association between simultaneous alcohol and marijuana use and blackout frequency among college students

Objective: The role of simultaneous alcohol and marijuana (SAM) use in the experience of blackouts among college students is unclear. To clarify discrepancies, the current study evaluated whether the association between SAM user status and blackouts was moderated by high-intensity drinking (HID). Participants and Methods: College students (N = 1,224; 63.7% female) reported on their past year experiences of blackout, marijuana use, SAM use, and HID (i.e., drinking at least twice the binge threshold). Results: SAM users had more past year blackouts than non-SAM users, but this effect was only significant among SAM users who had engaged in HID in the past year (nonbinge: F(5,37) = 0.50, p = 0.49; binge: F(5,138) = 0.23, p = 0.63; HID: F(5,328) = 4.52, p = 0.03). Conclusions: Effects of SAM user status on the experience of alcohol-related blackouts may be limited to individuals who engage in HID.

Maturing out of alcohol and cannabis co-use: A test of patterns and personality predictors

OBJECTIVE

Reductions in substance involvement into adulthood are thought to represent a normative maturing out of substance use. However, patterns and predictors of maturing out of alcohol and cannabis co-use remain largely unstudied. Therefore, the current study tested developmental trajectories of alcohol and cannabis use from late adolescence into adulthood and whether late adolescent personality traits predicted trajectory class membership.

METHODS

Data come from a longitudinal study of family history of alcohol disorder (N = 458). Age bands were created to model trajectories of drinking quantity, negative alcohol consequences, and cannabis use frequency from late adolescence (age 18-22) to young adulthood (age 23-28) and adulthood (age 29-36). Participants reported on their sensation seeking, conscientiousness, and neuroticism during late adolescence and their typical drinking quantity, negative alcohol consequences, and cannabis use frequency at each age band.

RESULTS

Three trajectory classes were derived from an initial Parallel Process Growth Mixture Model: (1) low-risk maturing out of alcohol-only use, (2) high-risk maturing out of co-use, and (3) high-risk switchers who increased their cannabis use into adulthood. Late adolescent sensation seeking was associated with higher odds of being in both co-use trajectories, whereas a lack of conscientiousness was associated with higher odds of being a co-use switcher.

CONCLUSIONS

We identified heterogeneity in trajectories of co-use, which suggests that a lack of maturing out of alcohol involvement may be accompanied by increased cannabis use. Moreover, late adolescent personality traits may predispose individuals toward riskier developmental trajectories of substance use into adulthood.

Cannabinoids and solid organ transplantation: Psychiatric perspectives and recommendations

Cannabinoid use in patients seeking solid organ transplantation (SOT) is an important and unsettled matter which all transplantation clinicians regularly encounter. It is also a multifaceted, interprofessional issue, difficult for any specialty alone to adequately address in a research article or during clinical care. Such uncertainty lends itself to bias for or against cannabinoid use accompanied by inconsistent policies and procedures. Scientific literature in SOT regarding cannabinoids often narrowly examines the issue and exists mostly in liver and kidney transplantation. Published recommendations from professional societies are mosaics of vagueness and specificity mirroring the ongoing dilemma. The cannabinoid information SOT clinicians need for clinical care may require data and perspectives from diverse medical literature which are rarely synthesized. SOT teams may not be adequately staffed or trained to address various neuropsychiatric cannabinoid effects and risks in patients. In this article, authors from US transplantation centers conduct a systematized review of the few existing studies regarding clinician perceptions, use rates, and clinical impact of cannabinoid use in SOT patients; collate representative professional society guidance on the topic; draw from diverse medical literature bases to detail facets of cannabinoid use in psychiatry and addiction pertinent to all transplantation clinicians; provide basic clinical and policy recommendations; and indicate areas of future study.

Cannabis and cocaine use, drinking outcomes, and quality of life in general hospital inpatients with alcohol use disorder

Background: While associations between cannabis and cocaine use, and heavy drinking and quality of life (QOL), are well-established in the general population, it is unclear whether they are present in hospital inpatients with alcohol use disorder (AUD). The aim of the study was to assess associations between cannabis and cocaine use and two outcomes [heavy drinking days (HDDs) and QOL] among hospital inpatients with AUD. Methods: Hospitalized patients with AUD and at least one past-month HDD participated in this cross-sectional study. Cannabis and cocaine use were assessed using the Alcohol, Smoking, and Substance Involvement Screening Test. HDDs were assessed using the Timeline Followback. QOL was assessed by the WHOQOL-BREF instrument. Multivariable regression models assessed associations. Results: Of 248 participants, 225 (91%) had severe AUD. There were no statistically significant associations between: recent cannabis use and HDDs [Incidence Rate Ratio (IRR) = 0.95; 95% Confidence Interval (95% CI): 0.80, 1.14], cocaine use and HDDs [IRR = 0.88; 95% CI: 0.66, 1.18], or both cannabis and cocaine use and HDDs [IRR = 0.87; 95%CI: 0.70, 1.09], as compared to use of neither cannabis nor cocaine. Use of cannabis, cocaine, and both, were not associated with QOL [(odds ratio (OR) = 0.98; 95% CI:0.55, 1.74), (OR = 0.76; 95% CI:0.30, 1.93), (OR = 1.00; 95%CI: 0.49, 2.03), respectively]. Conclusions: Among hospital inpatients with AUD, there were no significant associations between cannabis and cocaine use, heavy drinking, or QOL. Our findings raise questions regarding how drug use affects AUD and whether similar results would be found among those with milder AUD and in prospective studies.

Longitudinal course of mental health symptoms among veterans with and without cannabis use disorder

OBJECTIVE

Cannabis use disorder (CUD) is the most common non-alcohol related substance use disorder (SUD) in the United States and is especially prevalent among returning veterans. The long-term mental health correlates of CUD remain unknown, which is significant given the rise in legalization and also recreational and medicinal cannabis use nationally.

METHOD

Using a gender-balanced, national sample of 1,649 veterans (n = 115 with CUD; 75.2% White; M age = 37.49, SD = 9.88), we used latent growth curve modeling to examine posttraumatic stress disorder (PTSD) symptom severity, depressive symptoms, generalized anxiety, alcohol use, and psychosocial functioning between veterans with versus without a prior diagnosis of CUD over five time points, spanning an average of 7 years.

RESULTS

Returning veterans with CUD compared to those without reported higher alcohol use, depression, anxiety, PTSD symptom severity, and worse psychosocial functioning at baseline. We observed nonlinear change across each outcome. We also found that CUD moderated change in alcohol use (quadratic: b = -.129, p < .001) and PTSD symptoms (quadratic: b = -.280, p = .019), such that individuals with CUD evidenced decelerated change and worse outcomes relative to veterans without a previously documented CUD diagnosis. Trajectories of depression, anxiety, and psychosocial functioning were similar across individuals with versus without CUD.

CONCLUSIONS

In the first long-term and longitudinal evaluation of mental health and alcohol use course among returning veterans, CUD was associated with worse and more persistent alcohol use and PTSD symptom severity over time. These data have implications for clinical assessment, case conceptualization, and treatment of veterans and may inform efforts to offset risk for hazardous drinking and PTSD following a diagnosis of CUD. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Towards quantifying the reciprocal associations between frequency of cannabis use and alcohol consumption: a cross-lagged analysis from the CONSTANCES cohort

OBJECTIVE

Disentangle the temporal relationships between frequency of cannabis use and alcohol consumption.

METHODS

A cross-lagged model providing standardised coefficients (SCs)±their standard errors in 13 255 men and 13 696 women enrolled in 2015 or 2016 in the French population-based 'CONSulTANts des Centres d'Examens de Santé' (CONSTANCES) cohort. Cannabis use was categorised as follows: 'No use during the past 12 months', 'Use during the past 12 months but not in the past month' and 'Use in the past month' for cannabis use at baseline, and No use during the past 12 months, 'Use less than once per month' and 'Use once per month or more' for cannabis use at 1 year of follow-up. Alcohol consumption was measured at baseline and at 1 year of follow-up and three categories were determined: low risk (<28 drinks per week in men; <14 drinks per week in women), moderate risk (≥28 and<42 in men; ≥14 and<28 in women) and high risk (≥42 in men; ≥28 in women). Analyses were adjusted for age, sex, education, income, tobacco consumption, self-rated health status and depressive symptoms.

RESULTS

Both associations from alcohol to cannabis and from cannabis to alcohol were significant (SC=0.02±0.01 with p=0.003 and SC=0.06±0.01 with p<0.001, respectively). However, the SC of the association from cannabis to alcohol was three times higher than the opposite association (p<0.001). After stratification for sex, SCs of the association from cannabis to alcohol were more than two times higher than for the opposite association in men, and more than four times higher in women (both p<0.001).

CONCLUSIONS

The association between frequency of cannabis use and subsequent alcohol consumption was stronger than the opposite association. This finding encourages considering the risk of increased alcohol consumption among cannabis users.

Patterns of Cannabis and Alcohol Co-Use: Substitution Versus Complementary Effects

PURPOSE

The purpose of this review is to discuss the literature regarding the concurrent use (co-use) of alcohol and cannabis and competing hypotheses as to whether cannabis acts as a substitute for (i.e., replacing the effects of alcohol, resulting in decreased use) or a complement to (i.e., used to enhance the effects of alcohol, resulting in increased use) alcohol. The impact of cannabis use on alcohol-related outcomes has received increased attention in the wake of ongoing legalization of cannabis for both medical and recreational purposes. Evidence for both hypotheses exists in the literature across a broad range of data collection methods and samples and is carefully reviewed here. In addition, various mechanisms by which cannabis may act as an alcohol substitute or complement are explored in depth with the goal of better understanding equivocal findings.

SEARCH METHODS

This review includes articles that were identified from a search for studies on alcohol and cannabis co-use, with a specific focus on studies exploring complementary versus substitution aspects of co-use. Search terms were included in Google Scholar, PsycINFO, MEDLINE, and Web of Science. Eligible studies were those that measured alcohol and cannabis co-use in human samples in laboratory, survey, or ecological momentary assessment studies, or that directly referenced substitution or complementary patterns of use.

SEARCH RESULTS

Search results returned 650 articles, with 95 meeting inclusion criteria.

DISCUSSION AND CONCLUSIONS

Results of this review reveal compelling evidence for both substitution and complementary effects, suggesting nuanced yet significant distinctions across different populations examined in these studies. Several mechanisms for the impact of cannabis use on alcohol-related outcomes are identified, including patterns and context of co-use, timing and order of use, cannabinoid formulation, pharmacokinetic interactions, and user characteristics (including diagnostic status), all of which may influence substitution versus complementary effects. This review will inform future research studies examining this topic in both clinical and community samples and aid in the development of treatment and prevention efforts targeting those populations most vulnerable to negative consequences of co-use. Finally, this review highlights the need for additional research in more diverse samples and the use of mixed-methods designs to examine both pharmacological and contextual influences on co-use.

Risks and Benefits of Cannabis and Cannabinoids in Psychiatry

OBJECTIVE

The United States is in the midst of rapidly changing laws regarding cannabis. The increasing availability of cannabis for recreational and medical use requires that mental health clinicians be knowledgeable about evidence to be considered when counseling both patients and colleagues. In this review, the authors outline the evidence from randomized double-blind placebo-controlled trials for therapeutic use of cannabinoids for specific medical conditions and the potential side effects associated with acute and chronic cannabis use.

METHODS

Searches of PubMed and PsycInfo were conducted for articles published through July 2021 reporting on "cannabis" or "cannabinoids" or "medicinal cannabis." Additional articles were identified from the reference lists of published reviews. Articles that did not contain the terms "clinical trial" or "therapy" in the title or abstract were not reviewed. A total of 4,431 articles were screened, and 841 articles that met criteria for inclusion were reviewed by two or more authors.

RESULTS

There are currently no psychiatric indications approved by the U.S. Food and Drug Administration (FDA) for cannabinoids, and there is limited evidence supporting the therapeutic use of cannabinoids for treatment of psychiatric disorders. To date, evidence supporting cannabinoid prescription beyond the FDA indications is strongest for the management of pain and spasticity.

CONCLUSIONS

As cannabinoids become more available, the need for an evidence base adequately evaluating their safety and efficacy is increasingly important. There is considerable evidence that cannabinoids have a potential for harm in vulnerable populations such as adolescents and those with psychotic disorders. The current evidence base is insufficient to support the prescription of cannabinoids for the treatment of psychiatric disorders.

Amphetamine-Type Stimulant Dependence and Association with Concurrent Use of Cocaine, Alcohol, and Cannabis: A Cross-Sectional Study

INTRODUCTION

Amphetamine-type stimulants (ATSs) are the second most commonly used class of illegal substances in Europe. Although concurrent substance use has been subject to research, little is known about associations between concurrent use of cocaine, alcohol, or cannabis and ATS dependence. We expect that the concurrent use of any of the substance, especially cannabis and cocaine, is associated with ATS dependence.

METHODS

Cross-sectional data were gathered within the European ATTUNE study in 2018/2019. Participants (N = 721) were asked about their consumption patterns and social, psychological, and economic situation. Multivariate logistic regressions were carried out for associations between ATS dependence and use combinations of frequent cocaine, alcohol, or cannabis, with the reference group of no frequent concurrent use (model 1). Model 2 calculated associations for ATS dependence with lifetime methamphetamine use for respective use combinations.

RESULTS

The study population was on average 28.9 years old (SD = 7.7), with the majority being male (63.5%). In model 1, the adjusted odds ratio (aOR) for frequent alcohol use was 0.70 (confidence interval [CI] 0.41-1.20). Similar results were shown for model 2 (aOR 0.82, CI 0.42-1.62). Frequent cannabis use significantly reduced the chance for ATS dependence by 50% in adjusted model 1 (aOR 0.50, CI 0.28-0.89) and by 62% in model 2 (aOR 0.38, CI 0.18-0.82). For frequent cocaine use, models 1 and 2 report an aOR at 1.37 (CI 0.58-3.25) and 2.39 (CI 0.77-7.43), although not statistically significant. Frequent users of all 3 substances had a significant 3-fold chance for ATS dependence (model 1: aOR 2.98, CI 1.16-7.63; model 2: aOR 2.95, CI 1.02-8.58).

DISCUSSION

Against initial hypotheses, frequent concurrent use of alcohol or cannabis generally decreased chances for ATS dependence. An explanation could be the study population, which consists of many irregular users of ATS, who mainly consume alcohol or cannabis. Cocaine generally increased chances, although results were not significant. The frequent use of all 3 substances together with ATS in the last year was significantly associated with dependence, thus reporting important information for treatment services. Further research is needed for disentangling causal relationships underlying these associations and for pinpointing consequences for relapse prevention and retention success.

Sex-dependent effects of alcohol administration on the urge to use cannabis

Alcohol and cannabis couse is highly prevalent and associated with various negative consequences. The likelihood of same day couse is high, especially among men, however, underlying mechanisms to their couse and its sex-dependent nature remain poorly understood. This study aims to elucidate the effects of controlled alcohol administration on the urge to use cannabis and considers sex-dependent effects. A community sample of non-treatment-seeking heavy drinkers (N = 37, 46% female) reporting cannabis use in the past 6 months completed an alcohol administration paradigm. Participants rated their urge to use cannabis and drink alcohol at baseline and at rising levels of breath alcohol concentration (BrAC). Mixed model analyses examined the effects of BrAC, sex, and their interaction on craving for cannabis. The relationships across urge for cannabis, urge for alcohol, and subjective responses to alcohol were also tested. There was a significant BrAC × Sex interaction on the urge to use cannabis, such that males reported increases in the urge to use cannabis at rising BrACs but females did not. Urge for alcohol significantly predicted urge for cannabis across rising levels of BrAC and this relationship was stronger in males than in females. Lastly, stimulation, but not sedation, during alcohol administration was positively associated with the urge for cannabis. Overall, these results suggest that the pharmacological effects of alcohol on the urge to use cannabis are sex-dependent and that the stimulant effects of alcohol are associated with a higher urge for cannabis. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Effect of alcohol, tobacco, and cannabis co-use on gray matter volume in heavy drinkers

OBJECTIVE

Alcohol, tobacco, and cannabis are the three most frequently used drugs in the United States and co-use is common. Alcohol, tobacco, and cannabis use has been separately associated with altered brain structure, and alcohol and tobacco co-use results in decreases in gray matter volume. Less is known about the effect of alcohol and cannabis co-use, and alcohol, tobacco, and cannabis tri-use. Therefore, this study examined the effect of co- and tri-use on gray matter volume, a measure of brain cell density, in heavy drinkers.

METHOD

Heavy drinkers (n = 237; 152m/85f; age = 32.52; white = 111; black = 28; Latino = 9; American Indian = 2; Pacific Islander = 4; Asian = 59; mixed = 15; other = 9) were classified into four groups based on their alcohol, tobacco, and cannabis use: alcohol only users (n = 70), alcohol and tobacco co-users (n = 90), alcohol and cannabis co-users (n = 35), and alcohol, tobacco, and cannabis tri-users (n = 42). All participants completed a structural MRI scan. Voxel-based morphometry was conducted to evaluate the effect of co-use on gray matter volume, with alcohol only users as the reference group. Age, sex, and scanner were included as covariates.

RESULTS

Alcohol and tobacco co-users had significantly decreased left orbitofrontal gray matter volume relative to alcohol only users (Cohen's d = .79). There were no differences in gray matter volume between the alcohol only and alcohol and cannabis co-users, or between the alcohol only and tri-user groups.

CONCLUSION

The additive effect of tobacco co-use on gray matter volumes in heavy drinkers was limited and localized. The effect of tri-use of alcohol, tobacco, and cannabis may have interacted, such that overlapping cannabis and tobacco use masked volume differences present in separate co-using groups. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Effects of cannabis use on alcohol consumption in a sample of treatment-engaged heavy drinkers in Colorado

BACKGROUND AND AIMS

Cannabis is commonly used among people who drink alcohol, but evidence suggests a nuanced relationship between alcohol consumption and cannabis use. In particular, among individuals undergoing alcohol treatment the impact of cannabis on alcohol intake may depend upon cannabis use frequency. We aimed to test the effects of within-day cannabis use on total drinks consumed and likelihood of binge drinking on a given day among all participants and compare these relationships between males and females and between individuals who reported infrequent and frequent cannabis use.

DESIGN

This observational study is a substudy of a larger randomized controlled trial (RCT). Individuals were included from the RCT if they reported any cannabis use and were divided into groups based on cannabis use patterns. Alcohol use was compared within and between groups.

SETTING

Individuals were recruited from 2016 to 2020 from community and university settings in Denver and Boulder, CO, USA.

PARTICIPANTS

Of the 182 individuals enrolled in the RCT, 96 cannabis-using subjects were included in these analyses.

MEASUREMENTS

Subjects completed a time-line follow-back (TLFB) at baseline, 4, 8 (end of treatment) and 20 weeks. Daily data on alcohol and cannabis use from the TLFB at all time-points were analyzed.

FINDINGS

Across the sample (n = 96), individuals drank approximately 29% fewer drinks [95% confidence interval (CI) = 18-39%, P < 0.001] and were 2.06 times (95% CI =1.37-3.08, P < 0.001) less likely to have a binge-drinking episode on days that cannabis was used compared with days that cannabis was not used. These patterns were observed in males, females and the infrequent and frequent cannabis use groups. Findings were inconclusive regarding differences in the association between cannabis use and alcohol outcomes when comparing males and females and when comparing infrequent and frequent cannabis use groups.

CONCLUSIONS

Heavy drinkers engaged in treatment to reduce their alcohol consumption who also use cannabis appear to increase their cannabis use on days when they reduce their alcohol consumption.

Frequency of cannabis use and alcohol-associated adverse effects in a representative sample of U.S. adolescents and youth (2002-2014) a cross-sectional study

Background

While the link between frequent cannabis use and alcohol use disorders is well documented, it is not clear whether alcohol drinkers who use cannabis less frequently are also vulnerable to alcohol use disorders. We estimate the association of frequency of past 12-months cannabis use with alcohol-associated adverse effects variables in the same time frame: alcohol dependence, heavy drinking, driving under alcohol influence, alcohol-related interpersonal problems, use after interpersonal problems, alcohol-related risky behaviors, and alcohol-related legal problems.

Methods

We analyzed data from U.S. individuals aged 12 to 25 years who participated in annual, cross-sectional U.S. National Surveys on Drug Use and Health from 2002 to 2014. Logistic regression models were used to examine the association of cannabis use with six alcohol-associated adverse effects variables. Frequency of cannabis use served as the primary independent variable, and were divided into four categories: frequent use (21–30 days per month), less frequent use (1–20 days per month), no use over the past 12 months, and no lifetime cannabis use. Alcohol dependence and six alcohol-associated adverse effects variables served as our primary outcomes.

Results

The study included 465,090 respondents aged 12 to 25 years, among all past-year cannabis users, (47.5%) were less frequent (1–20 days/month) users. Less frequent cannabis use was highest among male, 15–25-year-olds, and non-Hispanic white 11.8, 84 and 10.6%, respectively. In adjusted models, past-year less frequent cannabis use (1–20 days/month) was significantly associated with past-year alcohol dependence (adjusted odds ratio aOR 5.57, 95% confidence interval (CI) 5.5–6.4); heavy drinking in the past-year (aOR 3.41, 95% CI 3.2–3.5); alcohol-related interpersonal problems in the past-year (aOR 7.33, 95% CI 7.0–7.5); use after interpersonal problems (aOR 5.17, 95% CI 4.8–5.5); alcohol-related risky behaviors (aOR 7.29, 95% CI 7.0–7.5), and, driving under influence of alcohol (aOR 7.19, 95% CI 6.9–7.4). No cannabis use past-year were more likely to report alcohol dependence (aOR 2.81, 95% CI 2.6–3) compared with no lifetime cannabis use.

Conclusion

These findings indicated that within the general population, not only frequent cannabis user (21–30 days per month) but even less frequent cannabis use (1–20 days/month) was significantly associated with past-year alcohol dependence and alcohol-associated adverse effects than no lifetime cannabis use. These adverse alcohol-related outcomes associated with less frequent cannabis use, should be taken under careful consideration in alcohol use disorder treatment setting and policy planning.

Current marijuana use among women of reproductive age

BACKGROUND

The objective of this study was to estimate the prevalence of current (past 30 days) marijuana use and its associations with demographic, other substance use, chronic disease, physical health and mental health measures among women of reproductive age (18-44 years) in 12 US states.

METHODS

This analysis used 2016 Behavioral Risk Factor Surveillance System (BRFSS) data from 16,556 women of reproductive age in 12 US states. Women self-reported current marijuana use and covariates. Weighted χ² statistics and adjusted prevalence ratios (aPR) were calculated accounting for the complex survey design.

RESULTS

Among women of reproductive age, 9.9 % reported current marijuana use. Current cigarette use (aPR: 2.0, 95 % CI: 1.6, 2.6), current e-cigarette use (aPR: 1.9, 95 % CI: 1.4, 2.6), binge drinking (aPR: 2.6, 95 % CI: 1.9, 3.6), ever having received a depression diagnosis (aPR: 1.6, 95 % CI: 1.2, 2.1), and ≥14 days of poor mental health in the past 30 days (aPR: 1.8, 95 % CI: 1.3, 2.4) were all associated with higher adjusted prevalence of current marijuana use. Reporting ≥14 days of poor physical health within the last 30 was associated with a 40 % lower adjusted prevalence of current marijuana use (aPR: 0.6, 95 % CI: 0.4, 0.8).

CONCLUSION

Current marijuana use among women of reproductive age was associated with other substance use, poor mental health, and depression. As state laws concerning marijuana use continue to change, it is important to monitor usage patterns and to assess associated health risks in this population.

Does cannabis complement or substitute alcohol consumption? A systematic review of human and animal studies

BACKGROUND

Whether alcohol and cannabis complement or substitute each other has been studied for over two decades. In the changing cannabis policy landscape, debates are moving rapidly and spill-over effects on other substances are of interest.

AIMS

update and extend a previous systematic review, by: (a) identifying new human behavioural studies reporting on substitution and/or complementarity of alcohol and cannabis, and (b) additionally including animal studies.

METHODS

We replicated the search strategy of an earlier systematic review, supplemented with a new search for animal studies. Search results were crossed checked against the earlier review and reference lists were hand searched. Findings were synthesised using a narrative synthesis.

RESULTS

Sixty-five articles were included (64 in humans, one in animals). We synthesised findings into categories: patterns of use, substitution practices, economic relationship, substance use disorders, policy evaluation, others and animal studies. Overall, 30 studies found evidence for substitution, 17 for complementarity, 14 did not find evidence for either, and four found evidence for both.

CONCLUSIONS

Overall, the evidence regarding complementarity and substitution of cannabis and alcohol is mixed. We identified stronger support for substitution than complementarity, though evidence indicates different effects in different populations and to some extent across different study designs. The quality of studies varied and few were designed specifically to address this question. Dedicated high-quality research is warranted.

One Is Not Enough: Understanding and Modeling Polysubstance Use

Substance use disorder (SUD) is a chronic, relapsing disease with a highly multifaceted pathology that includes (but is not limited to) sensitivity to drug-associated cues, negative affect, and motivation to maintain drug consumption. SUDs are highly prevalent, with 35 million people meeting criteria for SUD. While drug use and addiction are highly studied, most investigations of SUDs examine drug use in isolation, rather than in the more prevalent context of comorbid substance histories. Indeed, 11.3% of individuals diagnosed with a SUD have concurrent alcohol and illicit drug use disorders. Furthermore, having a SUD with one substance increases susceptibility to developing dependence on additional substances. For example, the increased risk of developing heroin dependence is twofold for alcohol misusers, threefold for cannabis users, 15-fold for cocaine users, and 40-fold for prescription misusers. Given the prevalence and risk associated with polysubstance use and current public health crises, examining these disorders through the lens of co-use is essential for translatability and improved treatment efficacy. The escalating economic and social costs and continued rise in drug use has spurred interest in developing preclinical models that effectively model this phenomenon. Here, we review the current state of the field in understanding the behavioral and neural circuitry in the context of co-use with common pairings of alcohol, nicotine, cannabis, and other addictive substances. Moreover, we outline key considerations when developing polysubstance models, including challenges to developing preclinical models to provide insights and improve treatment outcomes.

Inclusion of Cannabis Users in Alcohol Research Samples: Screening In, Screening Out, and Implications

BACKGROUND

Alcohol and cannabis are frequently co-used, as 20-50% of those who drink alcohol report co-using cannabis. This study is based on the argument that alcohol researchers should enroll cannabis users in human laboratory studies of alcohol use disorder (AUD) to strengthen generalizability. This study examines how heavy drinking cannabis users differ from non-cannabis using heavy drinkers.

METHODS

In a community sample of non-treatment-seeking heavy drinkers (n = 551, 35% female), cannabis users were identified through: (a) self-reported cannabis use in the past 6 months and (b) positive urine toxicology test for tetrahydrocannabinol (THC). Cannabis users, identified as described previously, were compared with non-cannabis users on demographic and clinical characteristics.

RESULTS

Those who endorsed cannabis use in the past 6 months reported more binge drinking days. Participants who tested positive for THC had higher Alcohol Use Disorder Identification Test scores and more binge drinking days. Younger age and being a tobacco smoker were associated with an increased likelihood of cannabis use in the past 6 months, whereas male gender and being a tobacco use were associated with a greater likelihood of testing positive for THC. Individuals with cannabis use disorder (CUD) endorsed more depression and anxiety and had higher AUD symptom counts than cannabis users without CUD.

CONCLUSIONS

The inclusion of cannabis users in AUD samples allows for increased clinical severity. Excluding cannabis users from AUD studies may limit representativeness and expend unnecessary study resources. Lastly, tobacco use may explain a large portion of the effects of cannabis use on sample characteristics.

SHORT SUMMARY

Alcohol and cannabis are frequently co-used substances. In a sample of non-treatment-seeking heavy drinkers (n = 551, 35% female), cannabis users reported higher alcohol use and higher likelihood of tobacco use than non-cannabis users. Including cannabis users in alcohol research studies will improve representativeness and likely increase clinical severity.

Characteristics of Dispensary Patients that Limit Alcohol after Initiating Cannabis

Many patients have reported that they decrease their use of opioids after starting medical cannabis (MC) but less is known for alcohol. The objective of this exploratory study was to identify any factors which differentiate alcohol abaters from those that do not modify their alcohol use after starting MC (non-abaters). Comparisons were made to identify any demographic, dosing, or health history characteristics which differentiated alcohol abaters (N = 47) from non-abaters (N = 65). Respondents selected from among a list of 37 diseases/health conditions (e.g. diabetes, sleep disorders). Abaters and non-abaters were indistinguishable in terms of sex, age, or prior drug history. A greater percentage of abaters (59.6%) than non-abaters (40.6%, p < .05) reported using MC two or more times per day. Abaters were more likely to be employed (68.1%) than non-abaters (51.1%, p < .05). Abaters also reported having significantly more health conditions and diseases (3.3 ± 2.0) than non-abaters (2.4 ± 1.4, p < .05). This small study offers some insights into the profile of patients whose self-reported alcohol intake decreased following initiation of MC. Additional prospective or controlled research into the alcohol abatement phenomenon following MC may be warranted.

The relationship of cannabis decriminalization in Colorado and cannabis use in individuals with alcohol use disorders

OBJECTIVE

Over the past decade, cannabis use has become increasingly popular in states that include Colorado. During this time, alcohol use disorders (AUDs) and alcohol-related medical conditions have also been consistently recognized as public health problems with increasing prevalence in the state. Despite the widespread use of cannabis in Colorado, the epidemiology of cannabis use among those with AUDs has been poorly described. Therefore, we sought to examine cannabis use among individuals with likely AUDs and individuals with low-risk alcohol use during a time of major Colorado legislative changes before and after legalization of recreational cannabis in 2012.

METHODS

This study was a secondary data analysis conducted with information from 303 participants (80% male) in the Denver, CO metropolitan enrolled between August 2007 and April 2016 for studies related to alcohol and lung health. Of these participants, 188 (62%) were completing inpatient alcohol detoxification with likely AUDs. All participants completed the Alcohol Use Disorder Identification Test (AUDIT) to establish their likelihood of an AUD, and all had information on current cannabis use assessed by questionnaire and urine toxicology testing.

RESULTS

Individuals with likely AUDs more commonly used cannabis compared to control participants (42% vs 27%, p = 0.007). In multiple logistic regression analyses, participant type (likely AUD versus control), tobacco smoking, and age were significantly associated with cannabis smoking; however, the year of participant enrollment was not. Adjusted odds for cannabis use among participants with likely AUDs were 2.97 (1.51-5.82), p = 0.002, while odds for cannabis use among tobacco smokers were 3.67 (1.94-6.93), p < 0.0001. Among control participants, tobacco smoking increased odds of cannabis use seven-fold.

CONCLUSIONS

Our findings highlight the exceptionally high odds of cannabis use among individuals with likely AUDs undergoing alcohol detoxification at a Colorado treatment facility before and after legalization of recreational cannabis. Targeted investigations into the medical and psychiatric consequences of combined alcohol and cannabis use are urgently needed to define its health impact in these vulnerable individuals.

Potential for cannabis adaptation among participants in a drunk driving intervention

Background

Some alcohol interventions have been found to have the adverse outcome of increasing non-alcohol-related substance use. It is unknown, however, how changes in alcohol use over the course of alcohol ignition interlocks - a common DUI intervention - may impact other substance use.

Methods

Alcohol and cannabis use were measured using hair ethylglucuronide and Delta-9-Tetrahydrocannabinol concentrations in blood, respectively. Participants (N = 69) were measured at the interlock installation period and again 6-months later while the interlock was installed. A mixed ANOVA was conducted to examine changes in levels of ethanol and THC over time.

Results

On measures of marijuana use, there was a significant interaction effect between the group that increased alcohol use and time F(2, 66) = 7.863, p =.001; partial η ² =.192; as well as a main effect for time F(2, 66) = 21.106, p <.001; partial η ² =.242.

Conclusions

Installing interlocks may inadvertently increase cannabis use among those who decrease alcohol use. Crash risk associated with cannabis use is notably less than that of alcohol use, however, continued cannabis use may be problematic when the device is removed and alcohol use is expected to return to the higher pre-interlock levels.

Decreased drinking in adults with co-occurring cannabis and alcohol use disorders in a treatment trial for marijuana dependence: Evidence of a secondary benefit?

The purpose of the present study was to investigate whether cannabis dependent users who met criteria for a secondary diagnosis of alcohol use disorder (AUD) would increase their use of alcohol in response to decreasing their use of marijuana in a behavioral treatment trial for cannabis use disorder (CUD). This phenomenon is commonly known as "substance substitution." Participants were randomly assigned to one of four 9-session treatment conditions with cannabis and alcohol use measured at baseline, posttreatment, and at 4 follow-ups through 14 months. Of those enrolled (n = 198), 27 (13.6%) also met criteria for AUD. Linear mixed models were used to analyze alcohol use over time with cannabis use and time as predictors. Findings demonstrated that there were no associations between declines in cannabis use and changes in alcohol consumption in the full sample. However, among those with CUD who also had AUD, declines in cannabis use significantly predicted concurrent declines in alcohol use (p < .05). This study did not find evidence of substance substitution among individuals receiving treatment for CUD. Contrary to expectations, the results indicated that individuals with AUD were more likely to decrease, rather than increase, their alcohol use when they reduced their marijuana use. Treatment for CUD in this study appeared to result in improvements in substance use generally, at least for those with comorbid AUD.

A longitudinal examination of daily patterns of cannabis and alcohol co-use among medicinal and recreational veteran cannabis users

BACKGROUND

Prompted by the ongoing debate regarding whether cannabis serves as a complement to or substitute for alcohol, this study uses prospective data to examine daily associations between medicinal versus recreational cannabis and alcohol use in veterans.

METHODS

Three semi-annual waves of Timeline Followback Interview data were collected from a sample of veterans who reported co-using alcohol and cannabis on at least one day (N = 115; 56% medicinal users; 93% male; 62,100 observations). Linear mixed effects models were used to examine the association between daily cannabis use and number of drinks consumed across time for both medicinal and recreational users and to examine the frequency medicinal cannabis used to substitute for alcohol.

RESULTS

Compared to medicinal users, recreational users were more likely to drink more on cannabis use days relative to non-use days. Among medicinal users, those endorsing more frequent use of cannabis as a substitute for alcohol reported fewer number of drinks consumed on days when cannabis was used relative to non-use days.

CONCLUSIONS

Among veterans, recreational users are at greater risk for increased drinking when co-using cannabis at the daily level, an association that is stable over time. Medicinal users may be at lower risk for increased drinking on days when cannabis is also used, especially those who endorse using cannabis to substitute for alcohol. Findings help clarify the debate on cannabis-alcohol substitution or complementary associations in a sample of veterans and suggests that alcohol interventions should address cannabis use as a risk factor, especially for recreational users.

Differential item functioning analysis of the CUDIT and relations with alcohol and tobacco use among men across five ethnic groups: The HELIUS study

Cannabis use has been rising despite recognition of the negative consequences associated with heavy use. The severity of these consequences has been shown to differ across racial/ethnic groups, even when controlling for consumption levels. The present study conducted an item response theory (IRT) analysis of the Cannabis Use Disorders Identification Test (CUDIT) to better understand the patterns of problematic cannabis use and their relation with other substance use across ethnic groups in the Healthy Life in an Urban Setting (HELIUS) study. CUDIT responses from 1,960 cannabis-using African Surinamese, South-Asian Surinamese, Dutch, Moroccan, and Turkish ethnic origin participants were used to test for differential item functioning (DIF) within an IRT framework. After restricting the sample to men because of low frequency of use among women, several instances of uniform DIF were identified. Multiple-group IRT analysis yielded a harmonized cannabis use phenotype that was used to estimate ethnic group differences in problematic cannabis use and its relation to alcohol and tobacco co-use. These analyses suggested that cannabis users from certain ethnic minority groups experienced higher rates of problematic use than the majority group despite lower rates of cannabis use. Further, cannabis and tobacco use were positively related across groups, whereas only ethnic minority groups showed a positive relation between cannabis and alcohol use. These results demonstrate the importance of accounting for DIF when examining group differences in problematic cannabis use, and support prior evidence suggesting that certain ethnic minority groups may be more likely to experience problematic cannabis use and alcohol co-use relative to the majority group. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Cannabis use and psychiatric illness in the context of medical marijuana legalization: A clinical perspective

OBJECTIVE

More than half of the U.S. states have legalized medical marijuana. Emerging evidence suggests that medical marijuana legalization may increase marijuana use and cannabis use disorder (CUD). CUD is comorbid with, and exacerbates, numerous psychiatric conditions, including misuse of other substances. It is unclear if marijuana is a gateway to other drug use, if it is simply a marker of another variable or shared experiences. Thus, we aim to present a perspective of the potential impact of medical marijuana legalization on CUD, focusing on the relationship of CUD to other psychiatric disorders.

FINDINGS

Medical marijuana legalization may lead to problematic cannabis use in patients with depressive symptoms, individuals with genetic predispositions, and those with certain early life stressors or who use in order to cope. Past positive experience with marijuana use may contribute to patient desire to seek medical marijuana treatment. Despite approved indications, medical marijuana often only leads to partial relief of its intended target symptom. While recreational marijuana use increases likelihood of using other drugs and is detrimental to recovery from other substance use disorders, the relationship between medical marijuana use and polysubstance use or risk of addiction relapse is uncertain.

CONCLUSIONS AND RELEVANCE

Legalized medical marijuana use may increase rates of CUD, although further research is needed to clarify this association. Based on the literature, it is our perspective that patients with affective symptoms and those with other substance use disorders are at increased risk of developing CUD and its sequelae. Given the uncertainty surrounding how prescribed marijuana may interact with other disorders, it is paramount that clinicians make patient-specific judgments as to the risks and benefits of the treatment.

Alcohol, tobacco, and marijuana consumption is associated with increased odds of same-day substance co- and tri-use

BACKGROUND

Little is known about event-level patterns of marijuana co- or tri-use with alcohol and tobacco. Thus, the study goal was to examine patterns of same-day alcohol, cigarette, and marijuana co- and tri-use at the individual level in non-treatment-seeking alcohol users.

METHODS

Participants (N = 551) completed an in-person interview for alcohol, cigarette, and marijuana use over the previous 30 days, and the event-level substance use patterns of n = 179 participants who reported using each of these substances at least once per month were analyzed.

RESULTS

The use of alcohol, marijuana, or cigarettes independently increased the probability of subsequent, simultaneous co-use of one of the two remaining substances. The co-use of alcohol with cigarettes and marijuana with cigarettes produced generally additive effects on the odds of same day tri-use of marijuana and alcohol, respectively. Conversely, the co-use of alcohol and marijuana produced sub-additive effects on likelihood of cigarette use. Sex moderated several of the observed patterns of co- and tri-use: the relationship between alcohol or cigarette use predicting marijuana co-use was stronger in men, whereas the observed additive relationships between drug co-use leading to tri-use was stronger in women.

CONCLUSIONS

The presented results may aid in the understanding of how simultaneous co-use of marijuana with alcohol and/or tobacco relates to the etiology, maintenance, and treatment of comorbid and trimorbid substance use disorder. Replication and extension of the results in treatment seeking populations using more fine-grained analysis approaches, e.g. ecological momentary assessment, is needed.

Risks Associated with Mid level Cannabis Use Among People Treated for Alcohol Use Disorder

BACKGROUND

The relationships between cannabis use frequency with alcohol use, alcohol-related harms, and persistent alcohol use disorder (AUD) in a general population subsample of individuals previously treated for AUD were examined.

METHODS

Secondary analyses of the 2005, 2010, and 2015 U.S. National Alcohol Surveys, a nationwide general population sample of individuals ages 18+, were performed. The analytic subsample (N = 772) reported 3+ lifetime DSM-IV alcohol dependence criteria and prior AUD treatment. Primary exposure was past 12-month frequency of cannabis use (weekly or more, or "heavy;" more than monthly/less than weekly or "midlevel;" less than monthly or "light;" none). Primary outcomes were past 12-month total volume, average frequency of 5+ drinks/month, past 12-month alcohol-related harms, and past 12-month DSM-IV alcohol dependence.

RESULTS

Multivariable negative binomial and logistic regressions showed that the only cannabis users who consistently differed significantly from cannabis abstainers were midlevel users; specifically, more than monthly/less than weekly cannabis users drank 2.83 times as many drinks (95% CI: 1.43, 5.60); had 2.83 as many 5+ occasions (95% CI: 1.38, 5.79); had 6.82 times the odds of experiencing any harms (95% CI: 2.29, 20.33); and had 6.53 times the odds of persistent AUD as cannabis abstainers (95% CI: 2.66, 16.02; all ps < 0.05). The relationship between midlevel cannabis use and harms remained significant after adjustment for volume and frequency of 5+ (OR = 6.18, 95% CI: 1.35, 28.37).

CONCLUSIONS

Among those with lifetime AUD who have been to treatment, only more than monthly/less than weekly cannabis use is related to more alcohol-related harms and persistent AUD compared to cannabis abstinence. Heavier and lighter cannabis use is not related to worse alcohol outcomes compared to cannabis abstinence.

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.

Comorbidity of Symptoms of Alcohol and Cannabis Use Disorders among a Population-Based Sample of Simultaneous Users. Insight from a Network Perspective

Research into comorbidity of alcohol and cannabis use disorders has resulted in inconsistent findings, especially among simultaneous users, who used alcohol and cannabis together on a single occasion. This study investigated the association of alcohol and cannabis use disorders among simultaneous users using a network perspective, which considers direct relationships between symptoms. We used a subset of simultaneous alcohol and cannabis users driven from the representative population-based sample of young Swiss men cohort study on substance use risk factors (C-SURF) (n = 1559 at baseline and n = 991 at follow-up). Self-reported symptoms of alcohol and cannabis use disorders were collected. Network analyses included network estimation, visualization, and community detection tests. Alcohol and cannabis use symptoms were separated in two distinct clusters, with few paths between them (eleven positive edges at baseline, three at follow-up). Withdrawal symptoms were likely to connect the two disorders at baseline, but not at follow-up. Alcohol and cannabis use disorders appeared as separate disorders among simultaneous users. Our findings mitigated previous findings on the detrimental association between alcohol and cannabis use. Future studies should incorporate network analyses as a means to study comorbidity in other community and clinical samples to confirm our preliminary findings.

Cannabis use during alcohol treatment is associated with alcohol-related problems one-year post-treatment

BACKGROUND

Prior research shows that cannabis use during treatment for Alcohol Use Disorders (AUD) is related to fewer abstinent days from alcohol, although only among those who use cannabis 1-2x/month. Here we extend prior research by assessing the relationship between the frequency of cannabis use during AUD treatment and post-treatment alcohol-related consequences.

METHODS

Data come from the Combined Pharmacotherapies and Behavioral Interventions (COMBINE) Study, a large US randomized control trial of treatments for AUD. The current analyses include 206 cannabis users and 999 cannabis abstainers and compare longitudinal drinking data between those who used cannabis versus those who abstained during COMBINE treatment. The primary exposure was quartiles of cannabis use (Q1: less than 1x/month during treatment, Q2: 1-2x/month, Q3: 4-8x/month, Q4: 12x/month or more), with cannabis abstainers as the reference group. Outcomes were alcohol-related problems at the end of treatment and one-year post-treatment as measured by the Drinker Inventory Consequences.

RESULTS

Compared to cannabis abstinence, the most frequent use during treatment was related to 1.44 times as many physical consequences one-year post-treatment. Cannabis use was not related to physical consequences immediately after treatment, or to intrapersonal, interpersonal, social responsibility or impulse control problems at either post-treatment time point.

CONCLUSIONS

In a sample of individuals in treatment for AUD, using cannabis 12x/month or more during treatment is associated with increased rates of physical consequences attributed to alcohol use. Individuals in treatment for AUD who also use cannabis might benefit from reducing or stopping cannabis use to avoid alcohol-related physical problems.

Marijuana use is associated with alcohol use and consequences across the first 2 years of college

College entry is associated with marijuana initiation, and co-use of alcohol and marijuana is associated with problematic outcomes, including alcohol-related consequences. The present study explored if: (a) use of marijuana on a given day would be associated with greater alcohol use within the same day; (b) use of marijuana within a given week would be associated with increased alcohol-related consequences in that same week; and (c) the association between marijuana use and alcohol consumption and consequences varies across time or by precollege level of problematic alcohol use. Participants (N = 488 college student drinkers, 59% female) completed assessments of marijuana use, alcohol use, and alcohol consequences across 2 years. Analyses revealed: (a) daily marijuana use predicted greater number of daily drinks and estimated breath alcohol concentration; (b) weekly marijuana use predicted more weekly positive and negative alcohol consequences; (c) the effect of daily marijuana use on alcohol use strengthened over time, while the effect of weekly marijuana use on positive alcohol consequences reduced over time; and (d) precollege level of problematic alcohol use moderated the association between daily marijuana and alcohol use and weekly marijuana use and negative consequences. This study provides the first longitudinal evidence of the association between marijuana use and greater alcohol use and consequences in college students. Future research examining event-level measurement of alcohol and marijuana co-use is important for the prevention of alcohol-related consequences. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Differences in alcohol cognitions, consumption, and consequences among first-time DUI offenders who co-use alcohol and marijuana

BACKGROUND

A significant portion of alcohol-related DUI offenders engage in co-use of alcohol and marijuana (AM). Given expanding marijuana legalization and the impaired driving risks associated with co-use, it is of increased importance to understand how characteristics of AM co-users compare to those who use alcohol only (AO) in order to inform DUI interventions and prevent recidivism.

METHODS

Participants were 277 first-time DUI offenders enrolled in a first-time DUI offender program across three locations. Using well-established measures, we evaluated differences in alcohol-related cognitions (positive expectancies and self-efficacy), frequency and quantity of alcohol consumption, and alcohol-related consequences between AO users and AM co-users by running a series of multivariate generalized linear models.

RESULTS

Compared to AO users, AM co-users reported lower self-efficacy to achieve abstinence and avoid DUI. Differences in abstinence self-efficacy largely explain higher relative rates of average and peak drinking quantity and higher odds of binge drinking among AM co-user. Despite lower self-efficacy and higher drinking quantity, there were no significant differences between AM and AO-users on alcohol-related consequences and past month reports of drinking and driving.

CONCLUSIONS

Our results provide preliminary evidence that DUI offenders who co-use alcohol and marijuana have higher alcohol use and lower self-efficacy than AO-users, and long-term consequences for this group should be monitored in future research. DUI programs may screen and identify co-users and consider tailoring their interventions to build self-efficacy to address the risks associated with AM co-use uniquely.

Comorbid Cannabis and Tobacco Use Disorders in Hospitalized Patients with Psychotic-Spectrum Disorders

OBJECTIVE

Individuals with psychotic-spectrum disorders use tobacco and cannabis at higher rates than the general population and individuals with other psychiatric disorders, which may contribute to increased rates of medical problems and mortality. The present study examined whether individuals with psychosis and comorbid tobacco and/or cannabis use disorders exhibit differing clinical characteristics in terms of their sociodemographic, mental health, substance use, physical health, and medication use patterns. Elucidation of these profiles, and determining their relative severity, has important implications for treatment, including offering more targeted interventions based on type of comorbidity pattern.

METHODS

We examined the electronic medical records of 829 patients with psychotic-spectrum disorders admitted to a psychiatric hospital and categorized them as having: (1) cannabis use disorder (CUD); (2) tobacco use disorder (TUD); (3) comorbid cannabis and tobacco use disorders (CUD + TUD); or (4) neither disorder (no CUD/TUD). Multinomial logistic regression was used to compare the aforementioned groups on multiple variables controlling for age and sex.

RESULTS

Alcohol and stimulant use disorder diagnoses were each related to higher odds of having a CUD and CUD + TUD, relative to no CUD/TUD. Stimulant and polysubstance use disorder diagnoses were each related to higher odds of having a TUD compared to no CUD/TUD. Greater number of prescribed psychotropic medications was related to higher odds of a TUD compared to no CUD/TUD.

CONCLUSIONS

Although several differences between groups were accounted for by age of cannabis versus tobacco users, findings point to the importance of considering comorbid alcohol and substance use disorders among those with psychosis and CUD/TUD, as these comorbidities have important implications for screening and treatment selection during and following acute hospitalization.

Opioid Misuse as a Predictor of Alcohol Treatment Outcomes in the COMBINE Study: Mediation by Medication Adherence

BACKGROUND

Alcohol is often consumed with opioids and alcohol misuse interferes with treatment for opioid use disorder (OUD). Drug misuse is associated with worse alcohol use disorder (AUD) treatment outcomes, yet no studies have investigated the role of opioid misuse in AUD treatment outcomes.

METHODS

We conducted secondary analyses of the medication conditions of the COMBINE study (n = 1,226), a randomized clinical trial of medications (acamprosate and/or naltrexone) and behavioral interventions (medication management and/or behavioral intervention) for alcohol dependence. We examined associations between baseline opioid misuse and the use of cannabis and other drugs with time to first drinking day, time to first heavy drinking day, and the frequency and intensity of drinking during treatment and 1 year following treatment, based on latent profile analysis. Opioid misuse was defined as use of illicit or prescription opioids without a prescription or not as directed in the previous 6 months, in the absence of OUD. Self-reported cannabis and other drug use were also examined. Seventy individuals (5.7%) met the opioid misuse definition and 542 (44.2%) reported use of cannabis or other drugs without opioid misuse. We also examined medication adherence as a potential mediator.

RESULTS

Baseline opioid misuse significantly predicted the time to first heavy drinking day (OR = 1.38 [95% CI: 1.13, 1.64], p = 0.001) and a higher probability of being in a heavier and more frequent drinking profile at the end of treatment (OR = 2.90 [95% CI: 1.43, 5.90], p = 0.003), and at 1 year following treatment (OR = 2.66 [95% CI: 1.26, 5.59], p = 0.01). Cannabis and other drug use also predicted outcomes. Medication adherence partially mediated the association between opioid misuse, cannabis use, other drug use, and treatment outcomes.

CONCLUSIONS

Opioid misuse and other drug use were associated with poorer AUD treatment outcomes, which was partially mediated by medication adherence. Clinicians and researchers should assess opioid misuse and other drug use in patients undergoing AUD treatment.

Daily Patterns of Marijuana and Alcohol Co-Use Among Individuals with Alcohol and Cannabis Use Disorders

BACKGROUND

The study aims were to examine daily associations between marijuana and alcohol use and the extent to which the association differs as a function of cannabis use disorder (CUD) and/or alcohol use disorder (AUD) diagnosis.

METHODS

Timeline Followback interview data was collected in a study of veterans (N = 127) recruited from a Veterans Affairs hospital who reported at least 1 day of co-use of marijuana and alcohol in the past 180 days (22,860 observations). Participants reported 40% marijuana use days, 28% drinking days, with 37% meeting DSM-5 criteria for CUD, 40% for AUD, and 15% for both. Use of marijuana on a given day was used to predict a 3-level gender-adjusted drinking variable (heavy: ≥5 (men)/4 (women) drinks; moderate: 1 to 4/3 drinks; or none: 0 drinks). A categorical 4-level variable (no diagnosis, AUD, CUD, or both) was tested as a moderator of the marijuana-alcohol relationship.

RESULTS

Multilevel modeling analyses demonstrated that participants were more likely to drink heavily compared to moderately (OR = 2.34) and moderately compared to not drinking (OR = 1.61) on marijuana use days relative to nonuse days. On marijuana use days, those with AUD and those with AUD + CUD were more likely to drink heavily (OR = 1.91; OR = 2.51, respectively), but those with CUD were less likely to drink heavily (OR = 0.32) compared to moderately, nonsignificant differences between any versus moderate drinking in interaction models.

CONCLUSIONS

Heavy drinking occurs on days when marijuana is also used. This association is particularly evident in individuals diagnosed with both AUD and CUD and AUDs alone but not in those with only CUDs. Findings suggest that alcohol interventions may need to specifically address marijuana use as a risk factor for heavy drinking and AUD.

Medicinal versus Recreational Cannabis Use among Returning Veterans

BACKGROUND

Although increasing rates of cannabis use and cannabis use disorder (CUD) are well-documented among veterans, little is known about their use of cannabis specifically for medicinal purposes. The present study characterizes such use and compares veterans reporting cannabis use for medicinal (n = 66) versus recreational (n = 77) purposes on (a) sociodemographic factors, (b) psychiatric disorders (posttraumatic stress disorder [PTSD], major depressive disorder [MDD], and CUD), (c) other substance use, (d) reasons for cannabis use and cannabis-related problems, and (e) physical and mental health.

METHODS

Participants were veterans deployed post 9/11/2001 recruited from a Veterans Health Administration (VHA) facility (N = 143; mean [SD] age = 30.0 [6.6]; mean [SD] deployments = 1.7 [1.1]) who reported past-year cannabis use.

RESULTS

The most frequently endorsed conditions for medicinal cannabis (MC) use were anxiety/stress, PTSD, pain, depression, and insomnia. In logistic regression analyses adjusted for frequency of cannabis use, MC users were significantly more likely (OR = 3.16) to meet criteria for PTSD than recreational cannabis (RC) users. Relative to RC users, MC users reported significantly greater motivation for using cannabis to cope with sleep disturbance as well as significantly poorer sleep quality and worse physical health.

CONCLUSIONS

Veterans who use cannabis for medicinal purposes differ significantly in sleep, physical and mental health functioning than veterans who use cannabis for recreational purposes. PTSD and sleep problems may be especially relevant issues to address in screening and providing clinical care to returning veterans who are using cannabis for medicinal purposes.

Marijuana use is associated with intimate partner violence perpetration among men arrested for domestic violence

Intimate partner violence (IPV) is a serious public health problem. Substance use, particularly alcohol, is a robust risk factor for IPV. There is a small but growing body of research demonstrating that marijuana use is positively associated with IPV perpetration. However, research on marijuana use and IPV has failed to control for other known predictors of IPV that may account for the positive association between marijuana use and IPV perpetration. Therefore, the current study examined whether marijuana use was associated with IPV perpetration after controlling for alcohol use and problems, antisocial personality symptoms, and relationship satisfaction, all known risk factors for IPV. Participants were men arrested for domestic violence and court-referred to batterer intervention programs (N = 269). Findings demonstrated that marijuana use was positively and significantly associated with psychological, physical, and sexual IPV perpetration, even after controlling for alcohol use and problems, antisocial personality symptoms, and relationship satisfaction. Moreover, marijuana use and alcohol use and problems interacted to predict sexual IPV, such that marijuana use was associated with sexual IPV at high, but not low, levels of alcohol use and problems. These findings lend additional support to the body of research demonstrating that marijuana use is positively associated with IPV perpetration in a variety of samples. Results suggest that additional, rigorous research is needed to further explore why and under what conditions marijuana is associated with IPV perpetration.