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.

Naturalistic examination of the anxiolytic effects of medical cannabis and associated gender and age differences in a Canadian cohort.

BACKGROUND: The aim of the current study was to examine patterns of medical cannabis use in those using it to treat anxiety and to investigate if the anxiolytic effects of cannabis were impacted by gender and/or age. METHODS: Patient-reported data (n = 184 participants, 61% female, 34.7 ± 8.0 years) was collected through the Strainprint® app. Tracked sessions were included if the method of administration was inhalation, treatment was for anxiety and the product used was dried flower. The final analyzed dataset encompassed three of the most commonly utilized dried flower products in anxiety sessions. Independent sample t-tests were used. The core analysis examined within subject changes overtime (pre-medication to post-medication) and interactions between time with two candidate moderators [gender (male, female) and age (18-29, 30-39, and 40 + years old)] by using analysis of variance (ANOVA). For significant main effects of interactions, post hoc tests were conducted using a Bonferroni correction. A secondary analysis examined differences in proportion of emotives endorsed as a function of gender or age using chi-square test of independence. RESULTS: Cannabis consumption resulted in a significant decrease in anxiety scores among both males and females (average efficacy of 50%) and efficacy was similar across the three cultivars. However, gender differences in efficacy were identified in two of the cultivars. All age groups experienced significant reductions in their anxiety post cannabis consumption; however, the 40 + year old group had significantly less efficacy than the other groups. The overall optimal dosing for the entire cohort was 9-11 inhalations for males and 5-7 inhalations for females, with some variation in dosing across the different cultivars, genders and age groups. CONCLUSIONS: We found all three cultivars had significant anxiolytic effects and were well-tolerated. Some limitations of the study are the moderate sample size, self-reported diagnosis of anxiety, unknown comorbidities and experience with cannabis, whether other drugs or cannabis products were used, and restriction to solely inhaled administration. We suggest that the gender and age differences in optimal dosing could support both healthcare practitioners and patients initiate medical cannabis treatment for anxiety.

Cannabis Involvement and Demand in Frequent Concentrate Users Versus Predominantly Flower Users.

OBJECTIVE: Cannabis concentrate products contain more of the intoxicating cannabinoid, tetrahydrocannabinol, than flower products and, thus, may produce greater harm. Indeed, concentrate use is associated with greater cannabis dependence and problems (e.g., anxiety) than flower use. Given this, continued examination of concentrate versus flower use differences on associations with various cannabis measures may be useful. These measures include behavioral economic demand for cannabis (i.e., its subjective reinforcing value), use frequency, and dependence. METHOD: In the present study of 480 cannabis users, those who were frequent concentrate users (n = 176) were compared with predominantly flower users (n = 304) regarding the relationship of two latent drug demand metrics assessed by the Marijuana Purchase Task to cannabis use frequency (i.e., days of cannabis use) and cannabis dependence (i.e., Marijuana Dependence Scale scores). RESULTS: Two previously observed latent factors emerged, based on confirmatory factor analysis: amplitude, reflecting maximum consumption, and persistence, reflecting cost insensitivity. Group comparisons showed that amplitude was greater among the concentrate versus flower group, but no difference was found for persistence. Further, using structural path invariance testing, the factors were differentially associated with cannabis use frequency across groups. Amplitude was positively associated with frequency for both groups, whereas persistence was negatively associated with frequency for the flower group. Neither factor was associated with dependence for either group. CONCLUSIONS: Findings continue to indicate that the demand metrics, although distinct, can be parsimoniously condensed into two factors. In addition, method of administration (i.e., concentrate vs. flower use) may affect how demand for cannabis relates to frequency of use. Associations were notably stronger with frequency relative to dependence.

Latent classes of neurodevelopmental profiles and needs in children and adolescents with prenatal alcohol exposure.

BACKGROUND: Fetal alcohol spectrum disorder (FASD) resulting from prenatal alcohol exposure (PAE) is a common neurodevelopmental disorder, but substantial interindividual heterogeneity complicates timely and accurate assessment, diagnosis, and intervention. The current study aimed to identify classes of children and adolescents with PAE assessed for FASD according to their pattern of significant neurodevelopmental functioning across 10 domains using latent class analysis (LCA), and to characterize these subgroups across clinical features. METHODS: Data from the Canadian National FASD Database, a large ongoing repository of anonymized clinical data received from diagnostic clinics across Canada, was analyzed using a retrospective cross-sectional cohort design. The sample included 1440 children and adolescents ages 6 to 17 years (M = 11.0, SD = 3.5, 41.7% female) with confirmed PAE assessed for FASD between 2016 and 2020. RESULTS: Results revealed an optimal four-class solution. The Global needs group was characterized by high overall neurodevelopmental impairment considered severe in nature. The Regulation and Cognitive needs groups presented with moderate but substantively distinguishable patterns of significant neurodevelopmental impairment. The Attention needs group was characterized by relatively low probabilities of significant neurodevelopmental impairment. Both the Global and Regulation needs groups also presented with the highest probabilities of clinical needs, further signifying potential substantive differences in assessment and intervention needs across classes. CONCLUSIONS: Four relatively distinct subgroups were present in a large heterogeneous sample of children and adolescents with PAE assessed for FASD in Canada. These findings may inform clinical services by guiding clinicians to identify distinct service pathways for these subgroups, potentially increasing access to a more personalized treatment approach and improving outcomes.

Characterizing Clinical Heterogeneity in a Large Inpatient Addiction Treatment Sample: Confirmatory Latent Profile Analysis and Differential Levels of Craving and Impulsivity.

Background: Individuals with substance use disorders (SUDs) have highly heterogeneous presentations and identifying more homogeneous subgroups may foster more personalized treatment. This study used SUD and other psychiatric indicators to characterize latent subgroups of patients in a large inpatient addiction treatment program. The resulting subgroups were then analyzed with respect to differences on clinically informative motivational mechanisms. Methods: Patients (n = 803) were assessed for severity of SUD (ie, alcohol use disorder, drug use disorder), post-traumatic stress disorder, anxiety disorders, and major depressive disorder. Confirmatory latent profile analysis (CLPA) was used to identify latent subgroups, hypothesizing 4 subgroups. Subgroups were then characterized with respect to multiple indicators of impulsivity (ie, delay discounting and impulsive personality traits via the UPPS-P) and craving. Results: The CLPA confirmed the hypothesized 4-profile solution according to all indicators (eg, entropy = 0.90, all posterior probabilities ⩾.92). Profile 1 (n = 229 [32.2%], 24.9% female, median age in range of 45-49) reflected individuals with high alcohol severity and low psychiatric severity (HAlc/LPsy). Profile 2 (n = 193 [27.1%], 29.3% female, median age in range of 35-39) reflected individuals with high drug and psychiatric severity (HDrug/HPsy). Profile 3 (n = 160 [22.5%], 37.6% female, median age in range of 45-49) reflected individuals with high alcohol severity and psychiatric severity (HAlc/HPsy). Profile 4 (n = 130 [18.3%], 19.4% female, median age in range of 35-39) reflected individuals with high drug severity and low psychiatric severity (HDrug/LPsy). Both high comorbid psychiatric severity subgroups exhibited significantly higher craving and facets of impulsivity. Conclusions: The results provide further evidence of 4 latent subgroups among inpatients receiving addiction treatment, varying by alcohol versus other drugs and low versus high psychiatric comorbidity. Furthermore, they reveal the highest craving and impulsivity in the high psychiatric comorbidity groups, suggesting targets for more intensive clinical intervention in these patients.

A reinforcer pathology approach to cannabis misuse: Evaluation of independent and interactive roles of cannabis demand and delay discounting in a sample of community adults.

Cannabis use is prevalent and concerns about cannabis misuse are increasing. A reinforcer pathology approach emphasizes the roles of drug reinforcing value (demand) and overvaluation of immediate rewards (delay discounting [DD]) in drug use but has been applied to a lesser extent to cannabis. The present study investigated the independent and interactive roles of these processes in relation to cannabis misuse in a community sample of adult cannabis users (N = 324; 44.8% female; Mage = 33.25). Participants completed a Marijuana Purchase Task (MPT), the Monetary Choice Questionnaire (MCQ), and the Cannabis Use Disorder Identification Test-Revised (CUDIT-R) to assess demand, DD, and cannabis misuse, respectively. Zero-order correlations revealed significant associations between CUDIT-R scores and both the demand indices (|rs | = .21-.56, p < .01-.001) and DD (r = .21, p < .01). In multivariate analyses, lower elasticity (i.e., price insensitivity) was robustly associated with higher CUDIT-R scores, while other demand indicators did not explain additional unique variance. However, as elasticity, intensity, and Omax exhibited robust zero-order intercorrelations, shared variance appeared to drive the association. An interactive relationship between elasticity and DD was not significant. These findings indicate that cannabis misuse is associated with both cannabis demand, particularly as measured by insensitivity to escalating costs, and immediate reward orientation, but the relationship was not synergistic. These results support a reinforcer pathology approach to cannabis misuse and, although causality cannot be inferred cross-sectionally, suggest that evaluating the longitudinal significance of these indicators is warranted. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Pharmacological interventions for alcohol misuse in correctional settings: A systematic review.

BACKGROUND: The prevalence of alcohol use disorder (AUD) is estimated to be 10 times higher amongst individuals in the criminal justice system than the general population. Alcohol use is also one of the strongest modifiable risk factors for recidivism. One intervention that has been shown to be effective in reducing alcohol consumption in the general population is medication-assisted treatment (MAT), and this systematic review synthesized the existing evidence on MAT for AUD in correctional settings. METHODS: Empirical, peer-reviewed studies on approved medications for AUD in correctional populations were searched in major databases. One hundred sixty-two articles were initially screened and 14 eligible articles were included in the final review. Four articles examined disulfiram, and 10 articles examined naltrexone. RESULTS: The studies on disulfiram were considerably older than those on naltrexone, predating contemporary scientific standards. Disulfiram in combination with substantial contingencies in a supervised setting significantly reduced alcohol-related measures of consumption and recidivism and had acceptable safety and tolerability. All naltrexone studies showed significant reductions in alcohol-related measures, but effects on recidivism were mixed. The naltrexone studies indicated that it was highly acceptable and well tolerated. In addition, offenders receiving naltrexone had significantly greater medication adherence, treatment attendance, and treatment duration than with placebo. CONCLUSIONS: A small number of studies on pharmacological interventions for AUD in the correctional population suggest that MAT is effective in reducing alcohol consumption, although results on recidivism are mixed. On balance, the evidence was more supportive of naltrexone in reducing alcohol-related outcomes than disulfiram and it may also be a more feasible intervention in correctional settings. Further research on MAT to address AUD in correctional populations with larger sample sizes, longer duration, and in combination with behavioral interventions is warranted.

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.

Using an Optimized Marijuana Purchase Task to Examine Cannabis Demand in Relation to Cannabis Misuse in Heavy Drinking Emerging Adults.

OBJECTIVE: A behavioral economic approach to cannabis misuse emphasizes a crucial role of high drug demand (i.e., reinforcing value), which may be measured using a marijuana purchase task (MPT). The multiple indices from this measure have been associated with cannabis misuse, but somewhat inconsistently, possibly because of task variability across studies. Based on recent qualitative research, the current study implemented an optimized MPT to examine the underlying factor structure and the relationship between cannabis demand and both cannabis misuse and motivation to change. METHOD: Participants were two independent samples of emerging adults who reported cannabis use and heavy episodic drinking in the last month, one Canadian (n = 396) and the other American (n = 275). Both were assessed using an MPT, the Cannabis Use Disorder Identification Test (CUDIT), the Marijuana Adverse Consequences Questionnaire (MACQ), and readiness to change items. RESULTS: Principal component analyses of the MPT indices revealed the same two-factor latent structure in both samples, interpreted as Amplitude (intensity, Omax, elasticity) and Persistence (breakpoint, Pmax). Regressions revealed that Amplitude was significantly associated with CUDIT and MACQ in both samples. In the Canadian sample, Persistence was also significantly associated with CUDIT and MACQ, and both factors were associated with motivation to change. CONCLUSIONS: The optimized MPT generated a two-factor latent structure that was parallel across samples, and the Amplitude factor was consistently associated with cannabis misuse. The current findings indicate the robust relevance of behavioral economic demand for cannabis in relation to cannabis misuse but suggest that links to motivation may be sample-specific.

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.

Food addiction in a large community sample of Canadian adults: prevalence and relationship with obesity, body composition, quality of life and impulsivity.

BACKGROUND AND AIMS: Parallels between the persistent overconsumption of food and addictive drugs have given rise to the notion of food addiction. In a large community sample of Canadian adults, the current study examined the prevalence of food addiction and its relationship with obesity, quality of life and multiple indicators of impulsivity. A secondary goal was to analyze differences between obese and non-obese individuals with and without food addiction. DESIGN: Cross-sectional in-person assessment. SETTING: Hamilton, Ontario, Canada. PARTICIPANTS: A total of 1432 community adults (age = mean ± standard deviation = 38.93 ± 13.7; 42% male) recruited from the general community using print, bus and internet advertisements. MEASUREMENTS: Yale Food Addiction Scale 2.0, anthropometrics (including body mass index), body composition (e.g. body fat, muscle mass, body water), World Health Organization Quality of Life scale and impulsivity measures, including impulsive personality traits, delay discounting and behavioral inhibition. FINDINGS: The prevalence of food addiction was 9.3% and substantially below that of obesity (32.7%), although food addiction was significantly more common among obese individuals (18.5%, P < 0.001). Food addiction was associated with significantly lower quality of life in all domains (ßs = -0.21 to -0.34, Ps < 0.001) and significantly higher impulsive personality traits, particularly negative and positive urgency (ßs = 0.37 and 0.30, Ps < 0.001). Subgroup contrasts within both the obese and non-obese strata revealed that food addiction was associated with significantly lower quality of life in all domains (Ps < 0.001). Food addiction among non-obese individuals was also associated with higher body mass index (P < 0.001). CONCLUSION: In a general community sample, food addiction was present in slightly fewer than one in 10 individuals, approximately one-third the prevalence of obesity, but with twice the prevalence among obese individuals. Food addiction appears to be associated with substantively lower quality of life and elevations in impulsivity, particularly in deficits in emotional regulation.

High fructose corn syrup alters behavioural and neurobiological responses to oxycodone in rats.

There are indications that sugars in the diet can play a role in vulnerability to opioid abuse. The current study examined a range of neuro-behavioural interactions between oxycodone (OXY) and high fructose corn syrup (HFCS). Male Sprague-Dawley rats had access to HFCS (0 or 50%) over 26 days in their home cages and were subsequently tested on place conditioning induced by 0, 0.16 and 2.5 mg/kg OXY (3 pairings of drug and saline, each 30 min), as well as on locomotor responses to 0, 0.16 and 2.5 mg/kg OXY, and in-vivo microdialysis was employed to measure dopamine (DA) levels in the nucleus accumbens (NAc) in response to 0 and 2.5 mg/kg OXY. A complex set of interactions between HFCS exposure and responses to OXY were observed: HFCS increased place preference induced by OXY, it enhanced the suppressant effect of OXY on locomotion, and it attenuated OXY-induced elevation in DA overflow in the NAc. Taken together, these findings suggest that nutrition has the potential to influence some responses to opioids which may be relevant to their abuse.

Identifying Patterns of Alcohol Use and Obesity-Related Factors Among Emerging Adults: A Behavioral Economic Analysis.

BACKGROUND: Although heavy alcohol consumption and maladaptive eating behaviors have been shown to co-occur among college students, less is known about the co-occurrence of these behaviors in a more diverse community-dwelling, emerging adult sample. The purpose of this study was to: (i) identify classes of emerging adults by their reported alcohol consumption patterns, food addiction symptoms, and body mass index; and (ii) determine whether these classes differed on indices of behavioral economic reinforcer pathology (e.g., environmental reward deprivation, impulsivity, alcohol demand). METHOD: Emerging adult participants were recruited as part of a study on risky alcohol use (n = 602; 47% white, 41.5% Black; mean age = 22.63, SD = 1.03). Participants completed questionnaires on alcohol and food-related risk factors and underwent anthropometric assessment. RESULTS: Latent profile analysis suggested a four-profile solution: a moderate alcohol severity, overweight profile (Profile 1; n = 424, 70.4%), a moderate alcohol severity, moderate food addiction + obese profile (Profile 2; n = 93, 15.4%), a high alcohol severity, high food addiction + obese profile (Profile 3; n = 44, 7.3%), and a high alcohol severity, overweight profile (Profile 4; n = 41, 6.8%). Individuals in Profile 1 reported significantly lower levels of environmental reward deprivation than either Profile 2 or 3, and participants in Profile 3 reported significantly higher environmental reward deprivation than those in Profile 4 (p < 0.001). Profile 4 demonstrated significantly higher alcohol demand intensity and Omax and lower demand elasticity than Profile 1, Profile 2, or Profile 3. Profile 4 also demonstrated significantly greater proportionate substance-related reinforcement than Profile 1 (p < 0.001) and Profile 2 (p = 0.004). CONCLUSION: Maladaptive eating patterns and alcohol consumption may share common risk factors for reinforcer pathology including environmental reward deprivation, impulsivity, and elevated alcohol demand.

Multidimensional elements of impulsivity as shared and unique risk factors for food addiction and alcohol misuse.

Food addiction (FA) and alcohol misuse tend to co-occur, which suggests shared factors in the etiology and persistence of these health behaviors. One shared factor that has been linked to both is impulsivity, a multidimensional construct reflecting multiple facets of self-regulatory capacity. However, co-occurrence also raises issues of possible confounding if both domains are not considered concurrently, and the intersection between FA, alcohol misuse, and impulsivity has not been well characterized empirically. Therefore, the current study examined the intersection of FA, alcohol consequences, and multiple indicators of impulsivity. Participants were emerging adults reporting regular heavy episodic drinking recruited from Hamilton, Ontario (N = 730; ages 19.5-23). Participants completed measures of FA, alcohol problems, impulsive personality traits (i.e., Barratt Impulsiveness Scales, UPPS-P Impulsive Behavior Scales), impulsive choice (i.e., delay discounting), impulsive action (i.e., Go/NoGo task). Findings revealed a significant association between FA and alcohol-related consequences and both shared similar associations with specific impulsive personality traits (Positive and Negative Urgency, Lack of Premeditation, Motor and Attentional Impulsivity). However, alcohol-related consequences were uniquely associated with other impulsive personality traits (Lack of Perseverance, Sensation Seeking, Non-planning impulsivity) and impulsive choice, and FA was uniquely associated with impulsive action. Beyond alcohol-related consequences, FA was associated with additional variance in measures of impulsive personality traits (Positive and Negative Urgency, Lack of Premeditation, Motor Impulsivity, and Attentional Impulsivity) and impulsive action, but not impulsive choice. Overall, the current study reveals several common self-regulatory processes associated with both adverse drinking consequences and FA, and that the risk of inadvertent confounding appears to be limited.

Latent Profile Analysis of Heavy Episodic Drinking in Emerging Adults: A Reinforcer Pathology Approach.

BACKGROUND: Heavy episodic drinking (HED) is a major public health problem among emerging adults (individuals 18 to 25), but with considerable heterogeneity in concurrent substance use and psychopathology. The current study used latent profile analysis (LPA) to detect discrete subgroups of HED based on alcohol, other drug severity, and concurrent psychopathology. A reinforcer pathology approach was used to understand motivational differences among the latent subgroups. METHODS: Participants were 2 samples of emerging adults reporting regular HED, 1 Canadian (n = 730) and 1 American (n = 602). Indicators for the LPA were validated dimensional self-report assessments of alcohol severity, cannabis severity, other drug severity, nicotine dependence, depression, anxiety, posttraumatic stress disorder, and attention-deficit/hyperactivity disorder. Reinforcer pathology indicators were measures of alcohol demand, proportionate substance-related reinforcement, and discounting of future rewards. RESULTS: The LPA yielded parallel 3-class solutions in both samples. The largest subgroup was characterized by comparatively low substance severity and psychopathology (Low overall severity). The second largest subgroup was characterized by comparatively high alcohol and other drug severity (excluding tobacco) and high levels of psychopathology (Heavy alcohol & high psychiatric severity). The third subgroup exhibited high alcohol, smoking and intermediate levels of other substance use and psychopathology (Heavy alcohol, smoking, & intermediate psychiatric severity). The Heavy alcohol & high psychiatric severity and Heavy alcohol, smoking, & intermediate psychiatric severity subgroups exhibited significantly higher alcohol demand, greater proportionate substance-related reinforcement, and steeper delay discounting. CONCLUSIONS: Parallel latent subgroups of emerging adults engaging in HED were present in both samples, and the high-risk subgroups were significantly differentiated by the reinforcer pathology indicators. These latent profiles may ultimately inform heterogeneity in the longitudinal course of HED in emerging adults.

Predictors of premature treatment termination in a large residential addiction medicine program.

BACKGROUND: While inpatient programs are a common setting for addiction treatment, patients' premature termination is a major concern. Predicting premature treatment termination has the potential to substantially improve patient outcomes by identifying high-risk profiles and suggesting care paths that might reduce dropout. The current study examined the predictors of premature termination from an inpatient addiction medicine service. METHODS: In 1082 patients admitted to a large inpatient addiction medicine service, we used intake assessments of severity of alcohol use disorder, illicit drug use disorder, post-traumatic stress disorder (PTSD), anxiety disorders, and major depressive disorder to predict planned termination (n = 922) or premature termination (n = 160). We used two complementary analytic approaches-traditional binary logistic regression and a data-driven latent profile analysis (LPA). RESULTS: Binary logistic regression revealed that alcohol use severity, illicit drug use severity, and PTSD severity significantly predicted termination status, although alcohol use severity notably exhibited an inverse relationship. The LPA revealed four distinct profiles, with one profile exhibiting a significantly higher rate of premature termination and another exhibiting a significantly lower rate of premature termination. The high-risk profile was characterized by high drug severity, high comorbid psychopathology (PTSD, depression, and anxiety symptoms), but low alcohol severity. The low-risk profile was characterized by high alcohol severity, but low drug use and low comorbid psychopathology. CONCLUSIONS: These results provide converging evidence that illicit drug severity and psychiatric severity, and particularly PTSD, were associated with premature termination. Moreover, the LPA revealed distinct latent subgroups of patients with meaningfully higher and lower risk of premature termination, suggesting that addiction services should develop strategies for identifying high-risk individuals or develop care paths for high-risk symptom clusters. Approaches that are trauma-informed or otherwise focus on the management of comorbid psychiatric conditions may be particularly appropriate for reducing premature termination.

Effects of high fructose corn syrup on ethanol self-administration in rats.

OBJECTIVE: The addition of sweeteners to alcoholic beverages is thought to facilitate heavy alcohol consumption, and this may be of particular concern when the additive is high fructose corn syrup (HFCS). METHODS: Four experiments in male Sprague-Dawley rats were performed to investigate whether the addition of 25% HFCS to ethanol (5%, 10%, and 20% v/v ethanol) would alter its intraoral operant self-administration, palatability, and sensitivity to food deprivation stress. RESULTS: As anticipated, HFCS drastically increased ethanol intake, and this effect appeared driven by its caloric value. Importantly, HFCS increased the persistence of operant responding following extinction in animals trained to self-administer the combination, and the addition of HFCS to ethanol changed subsequent responses to ethanol, including increased palatability and intake. CONCLUSIONS: These results in rats suggest that the addition of HFCS to the list of ingredients in sweetened alcoholic beverages could play a significant role in the harmful consumption of ethanol-containing beverages.

The effect of heroin dependence on resumption of heroin self-administration in rats.

BACKGROUND: It has been proposed that relapse vulnerability in previously dependent individuals results from augmentation of drug-induced reinforcement due to repeated associations between the interoceptive properties of the drug and reduction of acute withdrawal distress. METHODS: To test this hypothesis, male Sprague-Dawley rats self-administered 0.05 mg/kg/inf heroin on continuous reinforcement (CR) and progressive ratio (PR) schedules. During this period, they also received injections of vehicle or escalating doses of heroin. Following tests of naloxone-precipitated withdrawal, as well as a drug-free period (4 days), and extinction (9 sessions), they were pre-treated with vehicle or yohimbine (0.5mg/kg, IV) and tested for resumption of heroin self-administration (0.05 mg/kg/inf) on CR and PR schedules, or tested for reinstatement in extinction conditions. RESULTS: Increased self-administration on the CR schedule was observed in the heroin-injected rats, but no group differences were observed on the PR schedule, in spite of greater signs of withdrawal precipitated by naloxone in the heroin-injected rats. More importantly, there were no group differences in resumption of heroin self-administration, and this was not altered by yohimbine. CONCLUSIONS: These results suggest that relapse vulnerability cannot be uniquely ascribed to enhanced reinforcing action of drugs; contextual and other conditioning factors must play a role in modulating resumption of drug intake after abstinence.