Simultaneous Alcohol And Marijuana Use Research Articles

Trends in simultaneous alcohol and marijuana use among US adult recent drinkers: Differences by sexual identity, 2015–2020

Simultaneous alcohol and marijuana (SAM) use has become increasingly prevalent among young adult populations. Moreover, lesbian, gay, and bisexual populations are at increased risk for substance use initiation. To date, little research has examined trends in SAM use by sexual identity. This study aimed to investigate trends in SAM use among recent drinkers using nationally representative data. Pooled data from the 2015–2019 and 2020 National Survey on Drug Use and Health (NSDUH) were examined among 120,061 individuals (5.75% LGB) 18 years or older who reported using alcohol in the past month. Given the methodological changes in the study design, we analyzed these waves separately. Covariates included age, race, biological sex, sexual identity, rurality, and past month use of tobacco. Weighted logistic regression models and trend analyses were conducted. An estimated 11,952 of the sample reported using marijuana during their last episode of drinking. A significant linear trend (b = 0.12) of increasing SAM use among recent drinkers from 2015 to 2019. When compared to heterosexual individuals, lesbian or gay (aPR: 1.44, 95% CI 1.26, 1.63) and bisexual (aPR: 1.92, 95% CI 1.77, 2.09) individuals were more likely to report SAM use. Among the entire sample, females had a lower risk of SAM use than males (aPR: 0.68, 95% CI 0.65, 0.72). For 2020, a total of 25,679 adults 18 years or older participated in the survey, with 2622 identifying as LGB and 54.1% reporting past month alcohol use. An estimated 1503 individuals reported SAM use. Consistent with our findings, of those reporting past month alcohol use, LGB populations were at higher risk for SAM use, with gay individuals (aPR: 1.59, 95% CI 1.11, 2.30) at increased risk and bisexual individuals having higher risk (aPR: 2.12, 95% CI 1.73, 2.60). SAM use among individuals presents several critical health concerns, especially for at-risk populations. Findings from the present study can inform tailored interventions to reduce minority stress and stigmatized identities are needed.

Daily level examination indicates that positive affect, but not negative affect, is associated with alcohol and marijuana use among adolescents and young adults.

Although there is growing evidence that alcohol use at the daily level is associated with positive but not negative affect, results are mixed when examining marijuana use and simultaneous alcohol and marijuana (SAM) use (i.e., use with overlapping effects). In addition, less is known about these daily level associations among diverse samples of adolescents and young adults. The present study will address these gaps. Participants (N = 1,006; 57.3% female, 43.1% White, Non-Hispanic, ages 15-25; Mage = 20.0) were part of a study on substance use that consisted of a 3-week ecological momentary assessment (EMA) burst design (eight surveys per week, up to 2×/day) that was repeated quarterly over a 12-month period. Within-person results indicated that on days with elevated positive affect, participants reported consuming more drinks, whereas positive affect was not significant for hours high from marijuana. In addition, on days with elevated negative affect, participants reported fewer hours high from marijuana. No association was found between negative affect and number of drinks. Finally, within-person results indicated that on alcohol or marijuana days with elevated positive affect, individuals were more likely to report SAM use. There was no association found between negative affect and SAM use. Results have implications such that in-the-moment interventions for alcohol and SAM use may be more salient when individuals have higher positive affect than average, whereas such interventions may be more relevant for marijuana use when negative affect is lower compared to average levels. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Daily-level simultaneous alcohol and marijuana use and its associations with alcohol use, marijuana use, and negative consequences in a young adult community sample.

Simultaneous alcohol and marijuana (SAM) use has been associated with greater alcohol use and consequences at the daily level, but limited research has examined SAM use in relation to marijuana use and its consequences. This study tested daily associations between SAM use and four outcomes: alcohol use (number of drinks), marijuana use (hours high), negative alcohol consequences, and negative marijuana consequences. A community sample of young adults [ages 18-25, mean (SD) = 21.61 (2.17) years] with recent alcohol and SAM use was recruited (N = 409; 50.9% female; 48.2% non-Hispanic/Latinx White). Participants completed a baseline survey and six 2-week bursts of daily surveys (81.1% of morning surveys completed) and reported on substance use and negative substance-related consequences. Multilevel modeling was used to test the main aims and to explore each specific consequence. Among days with any alcohol use, SAM use days were associated with consuming more drinks and experiencing more total negative alcohol-related consequences than non-SAM use days. Among days with any marijuana use, SAM use days were associated with more hours being high than non-SAM use days. Exploratory models showed that SAM use was related to five specific alcohol-related consequences and two specific marijuana-related consequences. These findings build upon prior research by showing that SAM use days are linked to consuming more drinks, reporting more hours being high from marijuana, and experiencing more total alcohol-related consequences even after controlling for the number of drinks, the number of hours high, any tobacco/nicotine use, and any other substance use. SAM use was also associated with a greater likelihood of experiencing some specific consequences related to alcohol and marijuana. The findings underscore the need for additional research on SAM use and marijuana-related outcomes.

How Does Being under the Influence Affect Willingness to Experience Overlapping Effects of Alcohol and Marijuana?

Objective This study tested how individuals anticipate they will respond to opportunities to engage in simultaneous alcohol and marijuana (SAM) use. Methods Two studies utilizing a within-subjects design were conducted. Study 1 was conducted in Spring 2021 and a replication (Study 2) was conducted in Fall 2021. Participants were presented with pairs of scenarios. One scenario pair compared how willing participants expected to be to get drunk if they were sober vs. high. Another pair compared how willing participants would be to take a hit of marijuana if they were sober vs. drunk. College attending young adults (Study 1: N = 173; female = 81%; Study 2: N = 212; female = 49.1%) with varying degrees of substance use experience were recruited. Results In Study 1 participants reported greater willingness to get drunk when sober than when high. This was qualified by a statistically significant interaction whereby differences were greater among those who had more experience with past 30-day heavy drinking. Similar findings emerged for willingness to use marijuana. Participants anticipated greater willingness to use marijuana when sober than when drunk. This was also qualified by a statistically significant interaction whereby differences were greater among experimental or established users of marijuana than among abstainers. Study 2 findings replicated those from Study 1. Conclusions College attending young adults state greater willingness to remain under the influence of one substance than to engage in SAM use when opportunities arise. Simultaneous use of alcohol and marijuana among college students is likely an exception, not the rule. Implications for prevention are discussed.

Longitudinal examination of high-risk drinking contexts: Daytime drinking, pregaming, and drinking games linked to high-risk alcohol use and negative consequences in young adults.

The contexts in which young adults drink alcohol play a salient role in alcohol-related outcomes and negative consequences at an event-level, but less is known about longitudinal risks. We collected longitudinal monthly data across 2 years on (a) daytime drinking, (b) pregaming/pre-partying, and (c) playing drinking games. We then examined associations between drinking in these contexts and within-person variability in alcohol consumption, consequences, and simultaneous alcohol and marijuana (SAM) use in a given month. We also examined the extent to which drinking in these contexts predicted hazardous drinking (using Alcohol Use Disorders Identification Test (AUDIT) scores) at a distal follow-up timepoint, controlling for baseline AUDIT scores. A community sample of 759 young adults (Mage = 21.1 years; 56.4% female) completed monthly surveys for 24 consecutive months and a distal 30-month follow-up. Multilevel models estimated within- and between-person associations between drinking context frequencies (daytime drinking, pregaming, drinking games) and alcohol-related outcomes (weekly consumption, consequences, SAM use). A single-level negative binomial regression tested associations between drinking context frequency averages across a two-year period and changes in AUDIT scores from baseline to a follow-up 2.5 years later. Over 75% of the sample of non-abstaining young adults reported drinking in each of the three contexts at least once during the 24-month period. Within-persons, young adults reported greater consumption, more negative consequences, and increased likelihood of SAM use during months that they drank in these contexts more often than usual. Each context was associated with negative consequences, even when controlling for alcohol use frequency. More frequent daytime drinking and pregaming, but not drinking games, were associated with increases in AUDIT scores at the 30-month follow-up, suggesting that there are potential long-term risks of drinking in these contexts. Findings suggest that daytime drinking, pregaming, and playing drinking games are high-risk contexts in terms of month-to-month and long-term risks. Additional research is needed on the various contexts in which young adults drink alcohol and the extent to which contextual factors interact with one another to amplify/reduce risks and harms.

Young Adult Physical, Social, and Temporal Contexts of Simultaneous Alcohol and Marijuana Use.

Simultaneous alcohol and marijuana (SAM) use is reported to be associated with heavier alcohol and marijuana use and more negative consequences, but less is known about the social, physical, and temporal contexts of SAM use. Young adults (N = 326, 51.2% male, 49.1% White non-Hispanic) who reported past-month SAM use completed up to 14 daily surveys across five bursts that assessed SAM use and negative consequences and social, physical, and temporal contexts. We used multilevel models to examine SAM use contexts' associations with alcohol/marijuana quantity and consequences. The social context of alone only (vs. with others only) was associated with consuming fewer drinks. Physical contexts that included using both at home and outside the home (vs. only at home) were associated with greater alcohol and marijuana quantity and negative consequences (but not after controlling for alcohol quantity); use outside the home only (vs. only at home) was associated with more alcohol use, more alcohol consequences (but not after controlling for alcohol quantity), and fewer marijuana consequences (even after controlling for marijuana quantity). The temporal context of first engaging in SAM use before 6 P.M. (vs. after 9 P.M.) was associated with greater alcohol and marijuana quantity and more marijuana consequences (but not after controlling for number of hours high), and first engaging in SAM use between 6 and 9 P.M. was associated with more hours high. SAM use contexts such as using with others, using outside the home, and using earlier in the evening are typically associated with greater alcohol/marijuana quantity and consequences.

Nuanced relations between simultaneous alcohol and cannabis use motives and negative consequences among college students: The role of multiple product use.

Simultaneous alcohol and marijuana (SAM) use is common, but it exacerbates negative consequences. Individuals use alcohol and cannabis products in different ways and have distinct reasons for use. The present study examines day-level effects of motives on consequences on SAM-use days, accounting for consumption, and tests whether using multiple alcohol (e.g., beer + liquor) and/or cannabis (e.g., concentrate + leaf) products on the same day mediates these relations. College students engaging in SAM use at least once in the past month (N = 281; Mage = 20.17) completed two bursts of 28 consecutive days of data collection. We examined within-person effects of motives (effect-enhancement, social, offered [it was offered], coping) on number of negative consequences and on experiencing hangover, nausea, or blackout; and indirect effects via two concurrent mediators: using multiple alcohol products and multiple cannabis products. Total effect models showed effect-enhancement motives were related to nausea, social motives to number of total consequences and hangover, and coping motives to blackout. Effect-enhancement, social, and offered motives evinced significant indirect effects on consequence outcomes via multiple alcohol, but not cannabis, product use. Coping motives did not exhibit significant indirect effects, and were related to multiple cannabis, but not alcohol, product use, although all other motives were related to both mediators. Findings support recent work demonstrating within-person relations between social motives and negative consequences on SAM-use days. Limiting the number of alcohol products consumed on SAM-use days may be beneficial, particularly for young adults using to enhance intoxication or for social reasons. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Using Young Adult Language to Describe the Effects of Simultaneous Alcohol and Marijuana Use: Implications for Assessment

Introduction: Prevalence of alcohol and marijuana use is highest in young adulthood and an increasing number of young adults report simultaneous alcohol and marijuana (SAM) use, which is consistently linked with numerous negative consequences. To better understand reasons for engaging in SAM use and to refine measurement of subjective effects of SAM use, this study aimed to identify (1) how young adults describe subjective experiences during a SAM use occasion and (2) how language describing subjective effects changes as a function of level of alcohol and marijuana use. Methods: Using Amazon’s Mechanical Turk (MTurk), 323 participants (53.6% women, 68.4% White, M age = 23.0 years) who reported past-month heavy episodic drinking and past-month SAM use were asked to list words to describe how they feel when using only alcohol, only marijuana, and various combinations of alcohol and marijuana. Results: SAM use language varied as a function of age and substance use behavior but was not associated with sex or race. Large differences in the terms used to describe subjective effects were observed when comparing different combinations of alcohol and marijuana use; most notably the term “cross-faded” appeared primarily when engaging at the heaviest combinations of alcohol and marijuana. Conclusion: Young adults have a wide range of vocabulary for describing subjective effects of SAM use, and subjective effects vary as a function of the level of each substance used. Future research should consider integrating such contemporary language when measuring subjective effects of SAM use.

Examining daily associations between mental health symptoms and simultaneous alcohol and marijuana use and consequences among young adults.

The present study examined daily associations between mental health symptoms (i.e., depression and anxiety symptoms) and simultaneous alcohol and marijuana (SAM) use and use-related negative consequences among young adults. Participants were a community sample of 409 young adults between the ages of 18-25 who drank alcohol at least three times in the past month and reported SAM use in the past month (Mage = 21.6, 50.9% female). A baseline assessment included a measure of SAM use motives, after which participants completed five 14-day bursts reporting daily mental health symptoms and alcohol/marijuana use. Daily mental health symptoms were not associated with SAM use likelihood. However, baseline SAM coping motives moderated the association between mental health symptoms and use such that young adults with stronger coping motives showed a stronger positive association between mental health symptoms and SAM use. Further, on SAM use days, reporting more mental health symptoms relative to one's average was associated with experiencing more use-related negative consequences, even after controlling for daily levels of alcohol and marijuana use (RR = 1.03, 95% CI = 1.01-1.05, p = .002). The association between daily mental health symptoms and SAM use depended on whether the young adults had coping motives for use. Daily fluctuations in mental health were associated with negative use-related consequences experienced on SAM use days regardless of motives. These findings highlight the potential importance of prevention and intervention strategies particularly on days when young adults are experiencing increased mental health symptoms. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Factors Associated with Simultaneous or Concurrent Use of Alcohol and Marijuana in Argentina

Background: The identification of factors promoting simultaneous alcohol and marijuana (SAM) use is important to promote early intervention efforts. The associations between impulsivity facets and SAM (or concurrent alcohol and marijuana, CAM) use have been analyzed in North American samples. These topics, however, remain unexplored in South American samples. This study assessed if internalizing symptoms, five impulsivity dimensions, and emotional regulation strategies differentiate between participants who reported last 2-month SAM use, CAM use, alcohol, or marijuana only use, or that reported no substance use. Methods: A sample of 1057 Argentinian citizens answered an online survey. A multinominal logistic regression was conducted on drug use membership. Results: Circa 25% of the sample reported SAM use. Higher sensation seeking differentiated between SAM use versus no substance use, and those with lower sensation seeking were more likely to be classified into the alcohol-only group or into the nonuse group, than into the SAM use group. Stress scores uniquely predicted membership into the alcohol-only category. Those with lower use of emotional suppression were more likely than nonusers to be classified in all drug use categories, except CAM use. Higher emotional suppression scores were associated with membership into the nonuse group or the alcohol-only group, when compared to the SAM use group. Hazardous drinking was significantly greater in SAM than in alcohol-only users. Conclusions: The study highlights the relevance of sensation seeking as a predictor of SAM use and pinpoints emotional suppression as common factor modulating hazardous drug use behaviors.

Simultaneous Alcohol and Marijuana Use Among Young Adults: A Scoping Review of Prevalence, Patterns, Psychosocial Correlates, and Consequences.

BACKGROUNDAlcohol and marijuana are commonly used by young adults, and use of both substances, particularly at the same time, is prevalent among this population. Understanding the prevalence, patterns, correlates, and consequences of simultaneous alcohol and marijuana (SAM) use is important to inform interventions. However, this literature is complicated by myriad terms used to describe SAM use, including use with overlapping effects and same-day co-use.OBJECTIVESThis scoping review identifies and describes the peer-reviewed literature focused on SAM use by young adults and distinguishes simultaneous use from same-day co-use of alcohol and marijuana. This review also provides a narrative summary of the prevalence of SAM use, patterns of SAM and other substance use, psychosocial correlates, and consequences of SAM use.ELIGIBILITY CRITERIAThis review is limited to papers written in English and published in peer-reviewed journals between January 2000 and August 2021. It includes papers assessing simultaneous use or same-day co-use of alcohol and marijuana among young adults ages 18 to 30. Review papers, qualitative interviews, experimental lab studies, policy work, toxicology or medical reports, and papers focused on neurological outcomes are excluded.SOURCES OF EVIDENCEPubMed, PsycINFO, and Web of Science databases were searched. Databases were selected and the search strategy developed in consultation with an information specialist.CHARTING METHODSA data charting form was utilized to specify which information would be extracted from included papers. Eight categories of data were extracted: (1) research questions and hypotheses; (2) sample characteristics; (3) study procedures; (4) definition of SAM use; (5) prevalence of SAM use; (6) patterns of SAM and other substance use; (7) psychosocial correlates of SAM use; and (8) consequences of SAM use.RESULTSA total of 1,282 papers were identified through initial search terms. Through double-blind title/abstract screening and full-text review, the review was narrowed to 74 papers that met review inclusion criteria. Review of these papers demonstrated that SAM use was prevalent among young adults, particularly among those who reported heavier quantities and more frequent use of alcohol and marijuana. Enhancement-related motives for use were consistently positively associated with SAM use. SAM use was associated with greater perceived positive and negative consequences of alcohol and/or marijuana use. Inconsistencies in prevalence, patterns, correlates, and consequences were found between studies, which may be due to large variations in measurement of SAM use, populations studied, methodological design (e.g., cross-sectional vs. intensive longitudinal), and the covariates included in models.CONCLUSIONSThe literature on simultaneous use and same-day co-use of alcohol and marijuana has expanded rapidly. Of the 74 included papers (61 on SAM use; 13 on same-day co-use), 60 papers (47 on SAM use; 13 on same-day co-use) were published within the last 5 years. Future research focusing on the ways in which SAM use confers acute risk, above and beyond the risks associated with separate consumption of alcohol and marijuana, is needed for understanding potential targets for intervention.

The Prospective Effects of Parents’ and Friends’ Approval of Drinking on Simultaneous Alcohol and Marijuana Use during College

Background: Recent reports indicate that simultaneous alcohol and marijuana (SAM) use is a growing health concern among college students. As SAM use consists of both alcohol and marijuana, risk factors associated with either can serve as plausible targets by prevention efforts to reduce SAM use. Objectives: To explore this, the current study investigated the direct and indirect effects of two established risk factors for drinking on SAM use: perceived parental permissiveness toward drinking and friends’ approval toward drinking (injunctive norms). Method: Incoming first-year students (N = 470) reported parental permissiveness, injunctive norms, alcohol use, and SAM use at baseline (T1) and 5 months later (T2). SAM use was assessed again 15 months post-baseline (T3). Path analysis was conducted to examine whether T2 variables mediated relationships between T1 variables and T3 SAM use. Results: Results revealed that T2 student alcohol use mediated the effects of T1 parental permissiveness, injunctive norms, and alcohol use on T3 SAM use. Conclusions/Importance: Findings from this study extend research on SAM use by identifying perceived parental permissiveness and injunctive drinking norms as risk factors for SAM use through their effects on alcohol use. Based on these findings, it is plausible that parent-based interventions and interventions targeting peer injunctive norms during the first year of college could be used to effectively prevent or reduce SAM use.

Unplanned versus planned simultaneous alcohol and marijuana use in relation to substance use and consequences: Results from a longitudinal daily study.

Objective: The current study expands the literature on simultaneous alcohol and marijuana (SAM) use by focusing on the distinction between unplanned and planned SAM use to identify potential intervention targets. This study explored whether unplanned or planned SAM use was associated with differences in alcohol and/or marijuana use and consequences. Method: A community sample of young adults (aged 18-25) with recent alcohol and SAM use was recruited [N = 409; mean (SD) = 21.61 (2.17) years; 50.9% female; 48.2% non-Hispanic/Latinx White]. Participants completed five 2-week bursts of online daily surveys (2 ×/day; 81.99% of morning and 82.23% of afternoon surveys completed) and reported on substance use intentions and behavior. Results: Descriptive findings showed that among days on which participants reported SAM use, 41.85% of the days were unplanned SAM use days. Based on daily-level results from multilevel models, on days with unplanned SAM use, young adults reported consuming fewer drinks, fewer hours high from marijuana, and lower subjective intoxication/high, compared to planned SAM use days, thus indicating that planned SAM use was riskier. Unplanned SAM use was not significantly associated with positive or negative consequences related to alcohol or marijuana, after accounting for the number of drinks or hours high from marijuana. Conclusions: Current findings suggest that interventions should target days on which young adults are planning to engage in SAM use. Future work is needed to identify factors that predict planned SAM use on specific occasions and also to disentangle the potential role of unplanned heavy use. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Intoxicated driving and riding with impaired drivers: Comparing days with alcohol, marijuana, and simultaneous use

BackgroundYoung adults who engage in simultaneous alcohol and marijuana (SAM) use may be more likely to engage in unsafe behaviors including riding with impaired drivers and driving after alcohol and/or marijuana use. MethodsYoung adult SAM users (N = 408) self-reported their behavior for five 14-day bursts, yielding daily-level responses on a total of 14,675 substance use days. Adjusted odds ratios (AOR) estimated the likelihood of riding with an impaired driver and of driving after use on SAM use days compared to alcohol- or marijuana-only use days. ResultsMore frequent SAM users were more likely to ride with an impaired driver and to drive after use than less frequent SAM users (between-persons). On SAM use days, there were greater odds of riding with an impaired driver, compared to alcohol-only days (AOR = 1.28) and marijuana-only days (AOR = 2.22), and of driving after use, compared to marijuana-only days (AOR = 1.25). Driving after use was more likely on days with non-simultaneous alcohol and marijuana use compared to SAM use (AOR = 1.59). ConclusionsRiding with an impaired driver is common among young adult substance users, and more likely following simultaneous use of alcohol and marijuana compared to other types of alcohol and marijuana use. Driving after use is more likely after SAM use than marijuana-only use days, but most likely on days when both alcohol and marijuana were used but not simultaneously. Future research on situation-level predictors of riding and driving-related risks among young adults is warranted.

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.

The socio-environmental context of simultaneous alcohol and marijuana use among young adults: Examining day-level associations.

Simultaneous alcohol and marijuana (SAM) use is reported by roughly 30% of young adult drinkers. Among SAM users, SAM use days have more negative substance-related consequences than single-substance days. Little information is available about contextual factors contributing to the likelihood of SAM use on a particular day. This study compared days on which individuals reported SAM use relative to days on which they reported alcohol but not marijuana use in terms of physical location, engagement in risky activities and social context of use. Participants were 148 young adults (57% female) reporting past-month SAM use and past two-week binge drinking. Participants completed up to 14 daily surveys assessing substance use behaviour and socio-environmental characteristics of use. For those <21 years, only using at home was associated with greater odds of SAM use. For those 21+, using at a friend's house and outdoors were associated with increased odds of use; using at a bar/club was associated with lower odds. Using alone was associated with lower odds of use for those 21+. Engagement in risky activities (pre-gaming and drinking games) was not associated with SAM use. SAM days are linked with use in private settings and social situations. Despite experiencing more harms on SAM days, SAM use is not more likely than alcohol use alone to occur in certain environments and situations traditionally found to be linked with increased risk. Findings may provide key insight for developing context-informed interventions focused on SAM use.

Cross-fading motives for simultaneous alcohol and marijuana use: Associations with young adults’ use and consequences across days

BackgroundMany young adults engage in simultaneous alcohol and marijuana (SAM) use so that their effects overlap. Little is known about motivations for dual substance use and associations with use and consequences. This study examined daily-level associations between cross-fading motives and levels of alcohol and marijuana use and consequences. MethodsYoung adults who reported SAM use in the month prior were surveyed in two 14-day bursts. Data included 1049 SAM use days from 281 young adults (age 18–25; M age = 21.80, SD = 2.16; 50 % women). Multilevel models assessed between- and within-person effects of cross-fading motives (i.e., to enhance the effects of marijuana and/or alcohol use by using them simultaneously) on alcohol and marijuana use and consequences, after adjusting for general enhancement, social, coping, and conformity motives and the amount of alcohol and marijuana used that day. ResultsOn 76 % of SAM use days, participants endorsed cross-fading motives (i.e., to enhance the effect of alcohol or marijuana or to get drunk and high at the same time). Having stronger cross-fading motives was associated with greater alcohol use, perceived intoxication, and positive alcohol consequences at the between- and within-person levels. In addition, between-person, individuals who reported stronger cross-fading motives on average reported more negative alcohol consequences and positive marijuana consequences on average. Cross-fading motives on a given day were not associated with marijuana use or marijuana consequences that day. ConclusionsCross-fading motives were common and varied from day to day. Understanding the motivational context for dual substance use may support future interventions for cross-fading.

Simultaneous alcohol and marijuana use in daily life: Implications for level of use, subjective intoxication, and positive and negative consequences.

Simultaneous alcohol and marijuana (SAM) use is prevalent among young adult drinkers and associated with increased risk for harms. Less understood about SAM use is whether increased risk is incurred on SAM use occasions relative to occasions in which individuals used only 1 substance. From a sample of young adult SAM users, we compared occasions in which individuals simultaneously used alcohol and marijuana so that the effects overlapped ("SAM days"), occasions involving only alcohol ("alcohol days"), and occasions involving only marijuana ("marijuana days") on level of use, level of subjective intoxication, and negative and positive consequences. Eligible participants (N = 154; 57.8% female, 72.7% non-Hispanic/Latinx White) were 18-25 years old, reported past-month SAM use, and reported past 2-week binge drinking. Participants completed up to 14 daily assessments on their substance use behavior. Multilevel models indicated that, relative to alcohol days, SAM days had more negative consequences. SAM and alcohol days were not statistically different on level of use, level of subjective alcohol intoxication, or positive consequences. Relative to marijuana days, SAM days had more negative consequences and more positive consequences. Level of use (number of hits) and level of marijuana intoxication were not statistically different. In addition to SAM users being a more at-risk group, SAM occasions are associated with greater risk within this vulnerable population. Fine-grained ecological momentary assessments are needed to better understand perceptions and behavior throughout a SAM use episode. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Simultaneous Use of Alcohol and Marijuana: Patterns and Individual Differences

Background: Simultaneous alcohol and marijuana (SAM) use, or using alcohol and marijuana in such a way that their effects overlap, is associated with negative health and behavioral outcomes. Objectives: Our study sought to fill gaps in our knowledge on this emerging public health concern by comparing SAM users and alcohol-only users on individual-level factors and substance use outcomes as well as examining associations of SAM use frequency, within users. Methods: Participants were recruited through online postings. Our analytic sample consisted of 1017 young adults (18–25 years) who reported past-month alcohol use. Most were male (67.8%), Caucasian (71.5%), and had attended at least some college (74.8%). Results: Past-year SAM users reported higher levels of sensation seeking and greater perceptions of their close friends’ drinking behavior in comparison to alcohol-only users. SAM users reported heavier and more frequent alcohol use than alcohol-only users. Within past-year SAM users, 70% reported SAM use at least weekly. More frequent SAM use was associated with all alcohol use outcomes (e.g., weekly quantity, frequency, alcohol-related problems) and marijuana use outcomes (e.g., quantity, frequency, peak use) and higher drinking norms. Conclusions/Importance: It is clear that SAM users are a vulnerable sub-population of young adult drinkers. SAM users are differentiated from alcohol-only users in terms of their personality characteristics and perceptions of peer groups’ drinking. SAM users and more frequent users are also at heightened risk for substance use outcomes. Prevention and intervention efforts targeting high-risk drinking may benefit from also assessing whether they simultaneously use alcohol and marijuana.

Daily Motives for Alcohol and Marijuana Use as Predictors of Simultaneous Use Among Young Adults

Research on substance use motives typically examines each substance separately. However, simultaneous alcohol and marijuana (SAM) use-that is, using alcohol and marijuana at the same time so that their effects overlap-is common among young adults. This study examines day-to-day fluctuations in motives for using alcohol and/ or marijuana among young adult substance users as predictors of alcohol, marijuana, and SAM use across days. Data were from a community sample of young adults who reported SAM use in the past month (analytic sample: N = 399, mean [SD] age = 21.63 [2.17]; 50.9% women). Participants reported alcohol, marijuana, and SAM use, and also motives "for alcohol and/or marijuana use" for 14 consecutive days. Multilevel models showed that elevated enhancement motives were associated with heavy episodic drinking, drinking more, and more hours high from marijuana. Elevated social motives were associated with heavy episodic drinking and drinking more, and also with fewer hours high. Elevated conformity motives were associated with drinking more. SAM use was more likely: on alcohol days and on marijuana days with elevated enhancement and conformity motives, on alcohol days with elevated coping motives, and on marijuana days with elevated social motives. SAM use on a given day was primarily associated with enhancement and conformity motives. Social motives were more strongly linked to alcohol use, and to some extent coping motives were linked to marijuana use in this young adult sample. Further examination of situation-specific motives and contexts of use is needed to inform development of real-time interventions for SAM use and consequences.