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.

Aims We tested the age‐varying associations of cannabis use (CU) frequency and disorder (CUD) with psychotic, depressive and anxiety symptoms in adolescent and adult samples. Moderating effects of early onset (≤ 15 years) and sex were tested. Design Time‐varying effect models were used to assess the significance of concurrent associations between CU and CUD and symptoms of psychosis, depression and anxiety at each age. Setting and Participants Adolescent data (V‐HYS; n = 662) were collected from a randomly recruited sample of adolescents in Victoria, British Columbia, Canada during a 10‐year period (2003–13). Adult cross‐sectional data (NESARC‐III; n = 36 309) were collected from a representative sample from the United States (2012–13). Measurements Mental health symptoms were assessed using self‐report measures of diagnostic symptoms. CU was based on frequency of past‐year use. Past‐year CUD was based on DSM‐5 criteria. Findings For youth in the V‐HYS, CU was associated with psychotic symptoms following age 22 [ b = 0.13, 95% confidence interval (CI) = 0.002, 0.25], with depressive symptoms from ages 16–19 and following age 25 ( b = 0.17, 95% CI = 0.003, 0.34), but not with anxiety symptoms. CUD was associated with psychotic symptoms following age 23 ( b = 0.51, 95% CI = 0.01, 1.01), depressive symptoms at ages 19–20 and following age 25 ( b = 0.71, 95% CI = 0.001, 1.42) and anxiety symptoms ages 26–27 only. For adults in the NESARC‐III, CU was associated with mental health symptoms at most ages [e.g. psychotic symptoms; age 18 ( b = 0.22, 95% CI = 0.10, 0.33) to age 65 ( b = 0.36, 95% CI = 0.16, 0.56)]. CUD was associated with all mental health symptoms across most ages [e.g. depressive symptoms; age 18 ( b = 0.96, 95% CI = 0.19, 1.73) to age 61 ( b = 1.11, 95% CI = 0.01, 2.21)]. Interactions with sex show stronger associations for females than males in young adulthood [e.g. V‐HYS: CUD × sex interaction on psychotic symptoms significant after age 26 ( b = 1.12, 95% CI = 0.02, 2.21)]. Findings were not moderated by early‐onset CU. Conclusions Significant associations between cannabis use (CU) frequency and disorder (CUD) and psychotic and depressive symptoms in late adolescence and young adulthood extend across adulthood, and include anxiety.

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 1,017 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.

Background Heavy episodic drinking (HED) or consuming 4+/5+ drinks in one occasion for women/men is linked consistently with alcohol-related harms. Recent research suggests that many individuals drink at levels more than twice this cutoff (8+/10+ drinks), commonly referred to as “high-intensity drinking.” Prevalence rates of high-intensity drinking and its dynamic association with alcohol use disorder across all ages, however, remain unknown. The current study used data from a nationally representative sample to document age-varying prevalence rates of HED-only drinking and high-intensity drinking, prevalence rates of alcohol use disorder for HED-only drinkers and high-intensity drinkers, and relative odds of experiencing an alcohol use disorder for high-intensity drinkers as compared to HED-only drinkers. Methods Data were from the National Epidemiologic Survey on Alcohol and Related Conditions-III (NESARC-III). The final analytic sample consisted of past-year drinkers aged 18 to 64 years (n=22,776). Results Time-varying effect modeling (TVEM) revealed that high-intensity drinking and HED-only drinking were equally prevalent during young adulthood and prevalence rates of both types of drinking generally became less common with increasing age. At all ages, high-intensity drinkers were at three or more times greater odds of meeting criteria for an alcohol use disorder than HED-only drinkers. The association between high-intensity relative to HED-only drinking was strongest earlier in adulthood with approximately 83% of 18-year-old high-intensity drinkers having AUD relative to 42% of HED-only drinkers. Conclusions Future research aiming to identify drinkers most at risk for harms and in need of treatment may benefit from assessing the extent to which an individual exceeds the 8+/10+ threshold of drinking.

Influential psychological theories hypothesize that people consume alcohol in response to the experience of both negative and positive emotions. Despite two decades of daily diary and ecological momentary assessment research, it remains unclear whether people consume more alcohol on days they experience higher negative and positive affect in everyday life. In this preregistered meta-analysis, we synthesized the evidence for these daily associations between affect and alcohol use. We included individual participant data from 69 studies (N = 12,394), which used daily and momentary surveys to assess affect and the number of alcoholic drinks consumed. Results indicate that people do not drink more often on days they experience high negative affect, but are more likely to drink and drink heavily on days high in positive affect. People self-reporting a motivational tendency to drink-to-cope and drink-to-enhance were estimated to consume more alcohol, but not to consume more alcohol on days they experience higher negative and positive affect. Results were robust across different operationalizations of affect, study designs, study populations, and individual characteristics. Based on our findings, we collectively propose an agenda for future research to explore open questions surrounding affect and alcohol use.

This event-level study examined within-person differences in consequences for college students who engaged in alcohol-only, marijuana-only, or simultaneous alcohol and marijuana (SAM) use across 18 weekend days. Participants (n ϭ 451) were asked to report consequences they experienced on each occasion across five different types of events: (a) heavier alcohol combined with marijuana; (b) lighter alcohol combined with marijuana; (c) heavier alcohol only; (d) lighter alcohol only; and (e) marijuana only. Occasions involving heavy drinking, alone and in combination with marijuana, were associated with higher rates of consequences relative to lighter alcohol-only occasions, lighter alcohol combined with marijuana occasions, and marijuana-only occasions. Light alcohol-only occasions did not significantly differ on consequences from lighter alcohol combined with marijuana occasions or marijuana-only occasions. Past research has shown SAM use is associated with more consequences compared with alcohol-only use. The current findings suggest that SAM use is not necessarily riskier than drinking or using marijuana alone. Results suggested that on heavy drinking occasions, the number of consequences did not significantly change by also using marijuana. Findings suggest the benefit of targeted intervention strategies to reduce harms associated with heavy drinking occasions with and without SAM use.

Affect regulation models state that affect both motivates and reinforces alcohol use. We aimed to examine whether affect levels and rates of change differed across drinking versus nondrinking days in a manner consistent with affect regulation models. Four hundred four regularly drinking adults, aged 18 -70 years, completed ecological momentary assessments over 3 weeks. Participants provided positive affect (PA; enthusiastic, excited, happy) and negative affect (NA; distressed, sad) reports during all prompts; alcohol consumption reports were also provided. Multilevel spline models revealed that on drinking days, PA was higher and NA was lower both before and after drinking compared to matched times on nondrinking days. PA and NA were also higher and lower, respectively, both before and after drinking, when heavy drinking days were compared to moderate drinking days. Examination of affect rates of change revealed that (a) accelerating increases in PA and accelerating decreases in NA preceded drinking initiation, (b) PA increases and NA decreases were seen up to 2 hr after drinking initiation, and (c) pre-and postdrinking PA increases were larger on heavy versus moderate drinking days, whereas only postdrinking NA decreases were larger on heavy drinking days. Results supported affect regulation models while adding nuance, showing accelerating changes in predrinking affect on drinking days and pre-and postdrinking differences in affect levels and rates of change across days of varying drinking intensity. Beyond theory, our results suggest that accelerating changes in affect may provide a clue to future commencement of heavy drinking, which may aid momentary intervention development.

The current investigation sought to examine “day of the week” drinking of an at-risk sample of nonstudent emerging adults and whether specific factors are associated with differential drinking patterns. Our study aims were to: (1) identify differences in weekday versus weekend drinking, (2) examine specific expectancies (i.e., sociability, tension reduction) and demographic factors (e.g., age, sex) as relating to weekend versus weekday drinking after controlling for harmful drinking and holiday drinking. Participants were 238 (63.4% men, 35.7% women; M age = 21.92 years) heavy drinking noncollege-attenders recruited from the community. They reported daily drinking for the previous 30 days and completed measures of harmful drinking, alcohol expectancies, and demographic information. Results showed that more drinks were consumed on the weekends (i.e., Thursday to Saturday) than weekdays, with 63% of drinks consumed on weekends. Multilevel modeling analyses indicated that weekday drinking was associated with tension reduction expectancies, social expectancies, sex, and age. Weekend drinking increases were related to social expectancies but not tension reduction expectancies. Our final model indicated that, after controlling for the effect of holiday drinking, the within-person weekday/weekend distinction explained 18% of the total variance. In general, our findings highlight the importance of alcohol expectancies and drinking contexts in understanding the drinking behaviors of nonstudents. The differential role of tension reduction and social facilitation expectancies on drinking throughout the week imply different cognitive pathways are involved in weekday versus weekend drinking and both types of expected alcohol effects should be targets of risk-reduction efforts with nonstudent drinkers.