Longitudinal examination of alcohol demand and alcohol-related reinforcement as predictors of heavy drinking and adverse alcohol consequences in emerging adults.

BACKGROUND AND AIMS: Behavioral economic theory predicts that high alcohol demand and high proportionate alcohol-related reinforcement are important determinants of risky alcohol use in emerging adults, but the majority of research to date has been cross-sectional in nature. The present study investigated prospective and dynamic relationships between alcohol demand and proportionate alcohol-related reinforcement in relation to heavy drinking days and alcohol problems. DESIGN: Longitudinal cohort with assessments every 4 months for 20 months. SETTING: Ontario, Canada. PARTICIPANTS: Emerging adults reporting regular heavy episodic drinking (n = 636, Mage = 21.44; 55.8% female). MEASUREMENTS: Heavy drinking days (HDD; Daily Drinking Questionnaire), alcohol problems (Brief Young Adult Alcohol Consequences Questionnaire), alcohol demand (Alcohol Purchase Task) and proportionate alcohol-related reinforcement (Activity Level Questionnaire). FINDINGS: Linear mixed effects models revealed that behavioral economic indicators and alcohol-related outcomes significantly decreased over the study, consistent with 'aging out' of risky alcohol use. Random intercept cross-lagged panel models revealed significant between-person relationships, such that higher alcohol demand and alcohol-related reinforcement were positively associated with HDD and alcohol problems (random intercepts = 0.187-0.534, Ps < 0.01). Moreover, alcohol demand indicators (particularly the rate of change in elasticity of the demand curve, as measured by α, and the maximum expenditure, Omax ) and proportionate alcohol-related reinforcement significantly forecasted changes in HDD at all time points (|ßs| = 0.063-0.103, Ps < 0.05) in cross-lagged relationships, with bidirectional associations noted for the rate of change in elasticity (ßs = -0.085 to -0.104, Ps < 0.01). Proportionate alcohol-related reinforcement also significantly forecasted changes in alcohol problems at all time points (ßs = 0.072-0.112, Ps < 0.01). CONCLUSIONS: Multiple behavioral economic indicators (demand elasticity, maximum expenditure and reinforcement ratio) forecast changes in heavy episodic drinking and alcohol problems over the course of emerging adulthood. These results further implicate alcohol demand and proportionate alcohol-related reinforcement as etiologically and developmentally important mechanisms in alcohol use trajectories.

A high-resolution PheWAS approach to alcohol-related polygenic risk scores reveals mechanistic influences of alcohol reinforcing value and drinking motives.

AIMS: This study uses a high-resolution phenome-wide approach to evaluate the motivational mechanisms of polygenic risk scores (PRSs) that have been robustly associated with coarse alcohol phenotypes in large-scale studies. METHODS: In a community-based sample of 1534 Europeans, we examined genome-wide PRSs for the Alcohol Use Disorders Identification Test (AUDIT), drinks per week, alcohol use disorder (AUD), problematic alcohol use (PAU), and general addiction, in relation to 42 curated phenotypes. The curated phenotypes were in seven categories: alcohol consumption, alcohol reinforcing value, drinking motives, other addictive behaviors, commonly comorbid psychiatric syndromes, impulsivity, and personality traits. RESULTS: The PRS for each alcohol phenotype was validated via its within-sample association with the corresponding phenotype (adjusted R2s = 0.35-1.68%, Ps = 0.012-3.6 × 10-7) with the exception of AUD. All PRSs were positively associated with alcohol reinforcing value and drinking motives, with the strongest effects from AUDIT-consumption (adjusted R2s = 0.45-1.33%, Ps = 0.006-3.6 × 10-5) and drinks per week PRSs (adjusted R2s = 0.52-2.28%, Ps = 0.004-6.6 × 10-9). Furthermore, the PAU and drinks per week PRSs were positively associated with adverse childhood experiences (adjusted R2s = 0.6-0.7%, Ps = 0.0001-4.8 × 10-4). CONCLUSIONS: These results implicate alcohol reinforcing value and drinking motives as genetically-influenced mechanisms using PRSs for the first time. The findings also highlight the value of dissecting genetic influence on alcohol involvement through diverse phenotypic risk pathways but also the need for future studies with both phenotypic richness and larger samples.

Behavioral economic analysis of legal and illegal cannabis demand in Spanish young adults with hazardous and non-hazardous cannabis use.

BACKGROUND: In October 2021, a legal framework that regulates cannabis for recreational purposes in Spain was proposed, but research on its potential impacts on cannabis use is currently limited. This study examined the reliability and discriminant validity of two Marijuana Purchase Tasks (MPTs) for measuring hypothetical legal and illegal cannabis demand, and to examine differences in demand of both commodities in young adults at hazardous vs. non-hazardous cannabis use risk levels. METHODS: A total of 171 Spanish young adults [Mage = 19.82 (SD = 1.81)] with past-month cannabis use participated in a cross-sectional study from September to November 2021. Two 27-item MPTs were used to estimate hypothetical demand for legal and illegal cannabis independently. The Cannabis Use Disorder Identification Test (CUDIT-R) was used to assess hazardous cannabis use and test for discriminant validity of the MPTs. Reliability analyses were conducted using Classical Test Theory (Cronbach's alpha) and Item Response Theory (Item Information Functions). RESULTS: The MPT was reliable for measuring legal (α = 0.94) and illegal (α = 0.90) cannabis demand. Breakpoint (price at which demand ceases), and Pmax (price associated with maximum expenditure) were the most sensitive indicators to discriminate participants with different levels of the cannabis reinforcing trait. No significant differences between legal and illegal cannabis demand in the whole sample were observed, but hazardous vs. non-hazardous users showed higher legal and illegal demand, and decreased Breakpoint and Pmax if cannabis were legal vs illegal. CONCLUSION: The MPT exhibits robust psychometric validity and may be useful to inform on cannabis regulatory science in Spain.

High-resolution examination of changes in drinking during the COVID-19 pandemic: Nine-wave findings from a longitudinal observational cohort study of community adults.

Few multi-wave longitudinal studies have examined changes in drinking across extended periods of the coronavirus 2019 (COVID-19) pandemic. Using multiple indicators over three years, the current study examined: a) overall drinking changes; b) sex, income, age, and pre-COVID drinking level as moderators of changes; and c) the clinical significance of the observed changes. Using a longitudinal observational cohort design with nonclinical adults from the general community (N = 1395), assessments were collected over nine waves, two pre-COVID (April 2019 and October 2019) and seven intra-COVID (April 2020-April 2022). Drinking was measured as percent drinking days, percent heavy drinking days, and the Alcohol Use Disorders Identification Test (AUDIT) score. Clinically significant changes were defined based on the World Health Organization risk levels. All indicators exhibited significant changes from pre-pandemic to intra-pandemic periods, with drinking changes comprising early pandemic increases followed by subsequent decreases and AUDIT scores consistently declining. Pre-pandemic drinking level substantially moderated all changes. Heavier drinkers exhibited larger decreases compared to other drinking groups. In terms of clinically important changes, ∼10% of pre-pandemic abstinent or low-risk drinkers transitioned to medium- or high-risk status during the pandemic. In contrast, 37.1% of medium-risk drinkers and 44.6% of high-risk drinkers exhibited clinically significant decreases during the intra-pandemic period. Collectively, these findings highlight the multifarious impacts of the pandemic on drinking over time, comprising both increases and decreases in drinking behaviour.

Changes in posttraumatic stress disorder symptom severity during the COVID-19 pandemic: Ten-wave findings from a longitudinal observational cohort study of community adults.

Few studies have examined changes in posttraumatic-stress disorder (PTSD) symptomatology across an extended time period during the COVID-19 pandemic. This study used a longitudinal cohort design to examine: (1) changes in overall PTSD symptoms and symptom clusters; (2) moderators of change; (3) the clinical significance of observed changes; and (4) correlates of clinically meaningful changes. Community adults (N = 1412) were assessed using the PTSD Checklist for DSM-5 (PCL-5) at 10 timepoints (October 2018 - April 2022). Changes in overall PCL-5 score and symptom clusters were substantially moderated by pre-pandemic clinical severity (i.e., above/below PCL-5 cut-off). Pre-pandemic non-clinical participants exhibited increases in overall scores, Cluster D (negative cognitions), and Cluster E (arousal), while clinically elevated participants exhibited decreases overall and in all clusters. Regarding clinical significance, 12% of pre-pandemic non-clinical participants exhibited clinically meaningful increases, and 4% exhibited decreases. Conversely, 42% of the pre-pandemic elevated group exhibited clinically meaningful decreases, while 6% exhibited increases. Pandemic impacts in numerous psychosocial domains were associated with clinically meaningful change. Collectively, these findings reveal substantively divergent trajectories by pre-pandemic severity and PTSD symptom cluster. The large proportion of pre-pandemic high-severity participants exhibiting sizable decreases was an unexpected notable observation.

Cannabis Use Frequency and Cannabis-Related Consequences in High-Risk Young Adults Across Cannabis Legalization.

Importance: A key concern about recreational cannabis legalization is increases in use and adverse consequences, particularly among young adults (aged 18-29 years) who have the highest prevalence of cannabis use, and especially in higher-risk, more vulnerable young adults. However, few longitudinal studies have examined patterns of cannabis consumption in high-risk young adults over the course of legalization. Objective: To examine changes in cannabis use frequency and cannabis-related consequences over recreational cannabis legalization in Canada in a longitudinal sample of high-risk young adults. Design, Setting, and Participants: Longitudinal observational cohort study following young adults in Ontario, Canada, aged 19.5 to 23.0 years who reported regular heavy episodic drinking (65% past-month cannabis use) at enrollment. Participants were surveyed every 4 months for 3 years between February 2017 and February 2020 (3 prelegalization waves, 4 postlegalization waves). Data were analyzed from March to May 2023. Exposures: Recreational cannabis legalization in Canada and 4 potential moderators of change: sex, income, education, and prelegalization cannabis use frequency. Main Outcomes and Measures: Cannabis use frequency and cannabis-related adverse consequences. Results: In a cohort of 619 high-risk young adults (baseline mean [SD] age, 21.0 [1.2] years; 346 female participants [55.9%]), omnibus model testing revealed significant overall decreases in both cannabis use frequency (F = 2.276, 3000.96; P = .03) and cannabis-related consequences (F = 10.436, 3002.21; P < .001) over time, but these changes were substantially moderated by prelegalization frequency (frequency: F = 7.5224, 3021.88; P < .001; consequences: F = 7.2424, 2986.98; P < .001). Follow-up tests showed individuals who used cannabis more frequently prelegalization significantly decreased their use and cannabis-related consequences postlegalization. In contrast, individuals who did not use cannabis prelegalization exhibited a small magnitude increase in frequency over time but nonsignificant changes in cannabis-related consequences. Sex, income, and education did not moderate changes over time. Conclusions and Relevance: In this cohort study of high-risk young adults, individuals using cannabis frequently prelegalization showed significant reductions in use and consequences over time, reflecting an aging out pattern. Small increases in use among participants with no prelegalization use were observed over time, but without parallel changes in cannabis-related consequences. The results did not reveal substantive adverse near-term outcomes across the legalization period, although a within-participants design cannot rule out the possibility of alternative trajectories in the absence of legalization.

Applying behavioral economics to understand changes in alcohol outcomes during the transition to adulthood: Longitudinal relations and differences by sex and race.

OBJECTIVE: Population drinking trends show clear developmental periodicity, with steep increases in harmful alcohol use from ages 18 to 22 followed by a gradual decline across the 20s, albeit with persistent problematic use in a subgroup of individuals. Cross-sectional studies implicate behavioral economic indicators of alcohol overvaluation (high alcohol demand) and lack of alternative substance-free reinforcers (high proportionate alcohol-related reinforcement) as potential predictors of change during this developmental window, but longitudinal evidence is sparse. METHOD: Using a sample of emerging adults (N = 497, Mage = 22.61 years, 62% female, 48.69% White, 40.44% Black), this study examined prospective, bidirectional relations between both past-week heavy drinking days (HDD) and alcohol problems and proportionate alcohol-related reinforcement (reinforcement ratio), alcohol demand intensity (consumption at zero price), alcohol demand Omax (maximum expenditure), and change in demand elasticity (rate of change in consumption across escalating price) over five assessments (every 4 months) using random intercept cross-lagged panel models. RESULTS: Alcohol problems and HDD decreased across assessments. Significant between-person effects indicated that each behavioral economic variable was associated with increased drinking risk. Change in reinforcement ratio was positively associated with decreases in alcohol problems. Multigroup invariance modeling revealed distinct risk pathways in that change in demand intensity and Omax predicted change in alcohol problems for male participants and change in intensity predicted change in alcohol problems for non-White participants. CONCLUSION: The study provides consistent support for proportionate alcohol-related reinforcement and mixed support for demand as within-person predictors of reductions in drinking. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Periodicity and severity of changes in depression and anxiety during the COVID-19 pandemic: Ten-wave longitudinal findings from an observational cohort study of community adults.

AIMS: Few multi-wave longitudinal studies have examined mental health changes across the coronavirus 2019 (COVID-19) pandemic. The current study examined: (a) overall changes in depression and anxiety over 10-waves of data collection; (b) subgroup moderators of changes; (c) clinical severity of the changes via minimally important differences (MIDs); and (d) correlates of clinically important changes. METHODS: Using a longitudinal observational cohort design, 1412 non-clinical adults (Mage=36; 60% female) were assessed for depression and anxiety via the PHQ-9 and GAD-7 from October 2018 to April 2022 (3 pre-pandemic, 7 intra-pandemic waves; M retention = 92%). RESULTS: Depression and anxiety exhibited significant intra-pandemic changes, reflecting initial increases, followed by decreases. Pre-pandemic severity moderated changes, with low severity participants exhibiting increases and high severity participants exhibiting non-significant change or decreases. For depression and anxiety, respectively, 10% and 11% exhibited MID increases, while 4% and 6% exhibited MID decreases. Divergent patterns were present by severity subgroup, with the lowest severity exhibiting higher rates of MID increases and the highest severity subgroup exhibiting higher rates of MID decreases. CONCLUSIONS: These findings illuminate the periodicity of depression and anxiety during the COVID-19 pandemic and reveal an unexpected inverse relationship between increases and decreases based on pre-pandemic severity.

Leveraging related health phenotypes for polygenic prediction of impulsive choice, impulsive action, and impulsive personality traits in 1534 European ancestry community adults.

Impulsivity refers to a number of conceptually related phenotypes reflecting self-regulatory capacity that are considered promising endophenotypes for mental and physical health. Measures of impulsivity can be broadly grouped into three domains, namely, impulsive choice, impulsive action, and impulsive personality traits. In a community-based sample of ancestral Europeans (n = 1534), we conducted genome-wide association studies (GWASs) of impulsive choice (delay discounting), impulsive action (behavioral inhibition), and impulsive personality traits (UPPS-P), and evaluated 11 polygenic risk scores (PRSs) of phenotypes previously linked to self-regulation. Although there were no individual genome-wide significant hits, the neuroticism PRS was positively associated with negative urgency (adjusted R2 = 1.61%, p = 3.6 × 10-7 ) and the educational attainment PRS was inversely associated with delay discounting (adjusted R2 = 1.68%, p = 2.2 × 10-7 ). There was also evidence implicating PRSs of attention-deficit/hyperactivity disorder, externalizing, risk-taking, smoking cessation, smoking initiation, and body mass index with one or more impulsivity phenotypes (adjusted R2 s: 0.35%-1.07%; FDR adjusted ps = 0.05-0.0006). These significant associations between PRSs and impulsivity phenotypes are consistent with established genetic correlations. The combined PRS explained 0.91%-2.46% of the phenotypic variance for individual impulsivity measures, corresponding to 8.7%-32.5% of their reported single-nucleotide polymorphism (SNP)-based heritability, suggesting a non-negligible portion of the SNP-based heritability can be recovered by PRSs. These results support the predictive validity and utility of PRSs, even derived from related phenotypes, to inform the genetics of impulsivity phenotypes.

Concurrent validity of the marijuana purchase task: a meta-analysis of trait-level cannabis demand and cannabis involvement.

BACKGROUND AND AIMS: The Marijuana Purchase Task (MPT) is increasingly used to measure cannabis reinforcing value and has potential use for cannabis etiological and regulatory research. This meta-analysis sought to evaluate for the first time the MPT's concurrent validity in relation to cannabis involvement. METHODS: Electronic databases and pre-print repositories were searched for MPT studies that examined the cross-sectional relationship between frequency and quantity of cannabis use, problems, dependence, and five MPT indicators: intensity (i.e. unrestricted consumption), Omax (i.e. maximum consumption), Pmax (i.e. price at which demand becomes elastic), breakpoint (i.e. first price at which consumption ceases), and elasticity (i.e. sensitivity to rising costs). Random effects meta-analyses of cross-sectional effect sizes were conducted, with Q tests for examining differences by cannabis variables, meta-regression to test quantitative moderators, and publication bias assessment. Moderators included sex, number of MPT prices, variable transformations, and year of publication. Populations included community and clinical samples. RESULTS: The searches yielded 14 studies (n = 4077, median % females: 44.8%: weighted average age = 29.08 [SD = 6.82]), published between 2015 and 2022. Intensity, Omax , and elasticity showed the most robust concurrent validity (|r's| = 0.147-325, ps < 0.014) with the largest significant effect sizes for quantity (|r| intensity = 0.325) and cannabis dependence (|r| Omax = 0.320, |r| intensity = 0.305, |r| elasticity = 0.303). Higher proportion of males was associated with increased estimates for elasticity-quantity and Pmax -problems. Higher number of MPT prices significantly altered magnitude of effects sizes for Pmax and problems, suggesting biased estimations if excessively low prices are considered. Methodological quality was generally good, and minimal evidence of publication bias was observed. CONCLUSIONS: The marijuana purchase task presents adequate concurrent validity to measure cannabis demand, most robustly for intensity, Omax , and elasticity. Moderating effects by sex suggest potentially meaningful sex differences in the reinforcing value of cannabis.

Impacts of the COVID-19 public health restrictions on substance use, mental health, and psychosocial functioning among individuals with alcohol use disorder.

Background: The COVID-19 pandemic has been associated with major psychosocial disruptions and there is particular concern for individuals with substance use disorders.Objectives: This study characterized the psychosocial and experiential impacts of the pandemic on individuals seeking alcohol use disorder (AUD) recovery, including pandemic impacts on self-reported drinking, heavy drinking, tobacco, cannabis, and stimulant use.Methods: Participants were 125 AUD+ individuals (% males: 57.60; Mage = 49.11, SD = 12.13) reporting on substance use from January 1st-24th March, 2020 (pre-pandemic) and since the stay-at-home orders commenced, 24th March-June 28th 2020 (intra-pandemic). Within-subjects changes were examined and a latent profile analysis was performed to identify subgroups differentially impacted by the pandemic.Results: Large proportions reported psychosocial impacts of COVID-19, but drinking and other substance use did not reveal significant changes. Latent profile analyses revealed two subgroups: Profile 1 (n = 41/125), "Moderately Impacted") and Profile 2 (n = 84/125), "Severely Impacted"). Compared to the pre-pandemic period, the group that was moderately impacted by the pandemic exhibited significantly fewer heavy drinking days (p = .02) during the intra-pandemic period, but no other substance use changes. The group showing severe pandemic impacts did not exhibit changes in alcohol or other drug use but evidenced more severe anxiety and depression (ps < .001).Conclusions: We found heterogeneous subtypes of pandemic-related impacts in AUD recovery patients. There is need to provide psychosocial support to this particular population and further monitoring substance use and mental health.

Public health guideline compliance and perceived government effectiveness during the COVID-19 pandemic in Canada: Findings from a longitudinal cohort study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has imposed enormous adversity worldwide. Public health guidelines have been a first line of defense but rely on compliance with evolving recommendations and restrictions. This study sought to characterize adherence to and perceptions of public health guidelines over a one-year timeframe during the pandemic. METHODS: Participants were 1435 community adults in Ontario who completed assessments at five time points (April 2020, July 2020, October 2020, January 2021, and April 2021; 92% retention). Participants were assessed for self-reported adherence to government protocols and perceptions of government response (importance, compliance, and effectiveness). Analyses used general linear mixed-effects modelling of overall changes by time and examined differences based on age and sex. FINDINGS: Over time, participants reported high or increasing behavioural engagement in public health guidelines, including physical distancing, restricting activity, and masking. In contrast, participants exhibited significant reductions in perceived importance and compliance, with evidence of more negative changes in younger participants. The largest changes were a substantial reduction in perceived government effectiveness, from predominantly positive perceptions to predominantly negative perceptions. INTERPRETATION: These results illuminate evolving trends in public health compliance and perceptions over the course of the pandemic in Canada, revealing the malleability of public perceptions of public health recommendations and government effectiveness. FUNDING: This research was funded by a grant from the Canadian Institutes of Health Research (CIHR). CIHR had no role in study design, data collection, data analysis, interpretation, or writing of the report.

COVID-19 Vaccine Perceptions and Differences by Sex, Age, and Education in 1,367 Community Adults in Ontario.

Background: COVID-19 is a global pandemic and vaccination efforts may be impeded by vaccine hesitancy. The present study examined willingness to receive a COVID-19 vaccine, the associated reasons for willingness/unwillingness, and vaccine safety perceptions in a cross-sectional assessment of community adults in Ontario. Methods: One thousand three hundred sixty seven individuals (60.6% female, mean age = 37.5%) participated in this study between January 15, 2021 and February 15, 2021. Perceptions of vaccine safety and reasons for willingness/unwillingness to receive the COVID-19 vaccine were investigated using an online assessment. Perceptions were investigated in general and by age, sex and education using analysis of variance. Results: Overall, 82.8% of the sample reported they were willing to receive a COVID-19 vaccine and 17.2% reported they were unwilling. The three most common reasons for unwillingness were long-term side effects (65.5%), immediate side effects (60.5%), and lack of trust in the vaccine (55.2%). Vaccine willingness significantly differed by sex and education level, with female participants and those with less than a bachelor's degree being more likely to report unwillingness. Perception of COVID-19 vaccine safety was significantly lower (-10.3%) than vaccines in general and differed by age, sex and education, with females, older adults, and individuals with less than a bachelor's degree reporting lower perceived COVID-19 vaccine safety. Conclusion: In this sample of community adults, the COVID-19 vaccine hesitancy rate was less than one in five individuals, but with higher rates in population subgroups. Targeting public health messaging to females and individuals with less than bachelor's degree, and addressing concerns about long-term and immediate side effects may increase vaccine uptake.

Is talk cheap? Correspondence between self-attributions about changes in drinking and longitudinal changes in drinking during the 2019 coronavirus pandemic.

BACKGROUND: There are concerns that the coronavirus disease 2019 (COVID-19) pandemic may increase drinking, but most accounts to date are cross-sectional studies of self-attributions about alcohol-related impacts and the accuracy of those perceptions has not been investigated. The current study examined the correspondence between self-attributions of pandemic-related changes in drinking and longitudinally-measured changes in drinking and alcohol-related consequences in a sample of emerging adults. METHODS: In an existing ongoing longitudinal study on alcohol misuse (≥1 heavy episodic drinking day/month) in emerging adults, 473 individuals (Mage  = 23.8; 41.7% male) received a supplemental assessment from June 17th to July 1st, 2020, during public health restrictions in Ontario, Canada. These intrapandemic data were matched to the most recent assessment prior to the pandemic (~8 months earlier). Self-attributions about changes in drinking were assessed globally (i.e., increases/decreases/no change) and with higher resolution questions clarifying the magnitude of changes. RESULTS: Global self-attributions about changes in drinking substantively paralleled longitudinal changes in weekly drinking days (DD). In the longitudinal data, individuals' who self-reported increases in drinking exhibited significant increases; individuals' who self-reported decreases exhibited significant decreases; and individuals who self-reported no change exhibited nonsignificant changes. Higher resolution items likewise revealed longitudinal patterns of weekly drinking that were substantively consistent with self-attributions. Heavy DD and alcohol-related consequences exhibited similar patterns, but only individuals who self-reported large increases in drinking exhibited increases on these outcomes. Individuals who reported large increases in drinking also exhibited significant increases in depression and posttraumatic stress disorder symptoms. CONCLUSIONS: Self-attributions about drinking closely corresponded to longitudinal changes in drinking, supporting the validity of self-attributions in population-level surveys, particularly in young adults. Notably, a subgroup was identified that exhibited pronounced increases for all alcohol-related outcomes and concurrent increases in internalizing psychopathology.

COVID-19 impacts on drinking and mental health in emerging adults: Longitudinal changes and moderation by economic disruption and sex.

BACKGROUND: There are significant concerns that the COVID-19 pandemic may have negative effects on substance use and mental health, but most studies to date are cross-sectional. In a sample of emerging adults, over a two-week period during the pandemic, the current study examined: (1) changes in drinking-related outcomes, depression, anxiety, and posttraumatic stress disorder and (2) differences in changes by sex and income loss. The intra-pandemic measures were compared to pre-pandemic measures. METHODS: Participants were 473 emerging adults (Mage  = 23.84; 41.7% male) in an existing longitudinal study on alcohol misuse who were assessed from June 17 to July 1, 2020, during acute public health restrictions in Ontario, Canada. These intra-pandemic data were matched to participant pre-pandemic reports, collected an average of 5 months earlier. Assessments included validated measures of drinking, alcohol-related consequences, and mental health indicators. RESULTS: Longitudinal analyses revealed significant decreases in heavy drinking and adverse alcohol consequences, with no moderation by sex or income loss, but with substantial heterogeneity in changes. Significant increases in continuous measures of depression and anxiety were present, both of which were moderated by sex. Females reported significantly larger increases in depression and anxiety. Income loss >50% was significantly associated with increases in depression. CONCLUSIONS: During the initial phase of the pandemic, reductions in heavy drinking and alcohol consequences were present in this sample of emerging adults, perhaps due to restrictions on socializing. In contrast, there was an increase in internalizing symptoms , especially in females, highlighting disparities in the mental health impacts of the pandemic.

Cannabis use and misuse in the year following recreational cannabis legalization in Canada: A longitudinal observational cohort study of community adults in Ontario.

BACKGROUND: Canada legalized cannabis for non-medical purposes federally in October 2018. This study examined changes in cannabis use over the following year in a sample of general community adults. A secondary aim was to examine forecasted cannabis use following legalization in relation to actual post-legalization cannabis use. METHODS: Participants were 1502 community adults (61 % female; age M = 34.60 ± 13.95), with approximately half reporting any cannabis use in the six months prior to legalization (Cannabis+ group [48 %]/Cannabis- group [52 %]). Self-report assessments were conducted in the month before cannabis legalization, 6-months post-legalization and 12-months post-legalization. Primary outcomes were frequency of cannabis use, grams of dried flower cannabis on days used, and level of misuse (Cannabis Use Disorder Identification Test - Revised). Secondary analyses examined pre-legalization personal forecasts in relation to post-legalization cannabis use. RESULTS: Statistically significant main effects of time (ps<.001), cannabis use status (ps<.001), and time × cannabis use status interactions (ps<.001) were present for cannabis frequency, quantity, and level of misuse. In each case, the interactions reflected significant decreases in the Cannabis+ group, but significant increases in the Cannabis- group. Approximately 15 % of participants erroneously forecasted their personal post-legalization cannabis use, with discrepancies most commonly being individuals who were not using prior to legalization subsequently using cannabis. CONCLUSIONS: In this cohort of community adults, we observed significant changes over the first year following Canadian legalization, with divergent trajectories based on pre-legalization cannabis use. These findings suggest multifarious impacts of legalization in adults, with meaningfully different trajectories among subgroups.