Individual-, peer-, and parent-level substance use-related factors among 9- and 10-year-olds from the ABCD Study: Prevalence rates and sociodemographic differences.

Background: Although a relatively large body of research has identified multiple factors associated with adolescent substance use, less is known about earlier substance-related factors during preadolescence, including curiosity to use substances. The present study examined individual-, peer-, and parent-level domains pertaining to substance use and how these domains vary by sociodemographic subgroups and substance type. Methods: Participants were 11,864 9- and 10-year-olds from the baseline sample of the Adolescent Brain Cognitive Development (ABCD) Study. Youth-reported measures were curiosity to use substances and perceived peer substance use. Parent-reported measures were availability of and rules about substances. Generalized logistic mixed models (GLMM) were used to compare these measures across alcohol, nicotine, and marijuana and across sociodemographic subgroupings (sex, race/ethnicity, household income, and family history of alcohol problems). GLMM was then used to examine predictors of curiosity to use by substance type. Results: The most striking descriptive differences were found between race/ethnicity and income categories (e.g., positive associations between greater income and greater availability of alcohol). In multivariable analyses, greater curiosity to use alcohol was associated with being male, higher household income, perceived peer alcohol use, and easy alcohol availability; greater curiosity to use nicotine was associated with being male, perceived peer cigarette use, easy availability of cigarettes, and no parental rules about cigarette use. Conclusions: This study identified substance use-related individual-, peer-, and parent-level factors among a diverse, national sample. Findings highlight the importance of considering sociodemographic and substance-specific variability and may help identify risk and protective factors preceding adolescent substance use.

Alcohol use in emerging adults associated with lower rich-club connectivity and greater connectome network disorganization.

BACKGROUND: Emerging adulthood is a critical neurodevelopmental stage, with alcohol use during this period consistently associated with brain abnormalities and damage in anatomical structure and white matter integrity. However, it is less clear how alcohol use is associated with the brain's structural organization (i.e., white matter connections between anatomical regions). Recent connectome research has focused on rich-club regions, a collection of highly-interconnected hubs that are critical in brain communication and global network organization and disproportionately vulnerable to insults. METHODS: For the first time, we examined alcohol use associations with structural rich-club and connectome organization in emerging adults (N = 66). RESULTS: Greater lifetime drinks and current monthly drinks were significantly associated with lower rich-club organization (rs =-0.38, ps < 0.003) and lower rich-club connectivity (rs <-0.34, ps < 0.007). Additionally, rich-club connectivity was significantly more negatively correlated with alcohol use than connectivity among non-rich-club regions (ps < 0.035). Examining overall structural organization, greater lifetime drinks and current monthly drinks were significantly associated with lower network density (i.e., lower network resilience; rs <-0.36, ps = 0.004). Additionally, greater lifetime drinks and current monthly drinks were significantly associated with higher network segregation (i.e., network's tendency to divide into subnetworks; rs >0.33, ps<0.008). Alcohol use was not significantly associated with network integration (i.e., network's efficiency in combining information across the brain; ps > 0.064). CONCLUSIONS: Results provide novel evidence that alcohol use is associated with decreased rich-club connectivity and structural network disorganization. Given that both are critical in global brain communication, these results highlight the importance of examining alcohol use and brain relationships in emerging adulthood.

Moderation of alcohol craving reactivity to drinking-related contexts by individual differences in alcohol sensitivity: An ecological investigation.

Laboratory cue exposure investigations have demonstrated that, relative to drinkers who report a high sensitivity to the pharmacologic effects of alcohol, low-sensitivity (LS) drinkers show exaggerated neurocognitive and behavioral reactivity to alcohol-related stimuli. The current study extends this line of work by testing whether LS drinkers report stronger cravings for alcohol in daily life. Data were from an ecological momentary assessment study in which participants (N = 403 frequent drinkers) carried a palmtop computer for 21 days and responded to questions regarding drinking behavior, alcohol craving, mood states, and situational context. Initial analyses identified subjective states (positive and negative mood, cigarette craving) and contextual factors (bar-restaurant location, weekend, time of day, presence of friend, recent smoking) associated with elevated craving states during nondrinking moments. Effects for nearly all these craving correlates were moderated by individual differences in alcohol sensitivity, such that the associations between situational factors and current alcohol craving were larger among LS individuals (as determined by a questionnaire completed at baseline). Complementary idiographic analyses indicated that self-reported craving increased when the constellation of situational factors more closely resembled individuals' observed drinking situations. Again, this effect was moderated by alcohol sensitivity, with greater craving response increases among LS drinkers. The findings align with predictions generated from theory and laboratory cue exposure investigations and should encourage further study of craving and incentive processes in LS drinkers. (PsycINFO Database Record

WISDM Primary and Secondary Dependence Motives: Associations With Smoking Rate, Craving, and Cigarette Effects in the Natural Environment.

INTRODUCTION: The Wisconsin Inventory of Smoking Dependence Motives (WISDM) is a multidimensional measure of smoking motives that was developed to facilitate research aiming to refine the nomological network surrounding tobacco dependence. Recent evidence suggests that a composite of four subscales, termed the Primary Dependence Motives (PDM), may represent core features of advanced addiction, while the remaining nine subscales (Secondary Dependence Motives; SDM) represent instrumental motives for cigarette use that may be relevant at any stage of smoking. METHODS: A sample of 255 smokers (all regular alcohol users) participated in an ecological momentary assessment study in which they monitored smoking behavior and related experiences for 21 days. Multilevel regression analyses tested how PDM and SDM predicted daily smoking rate, cigarette craving, and appraisals of pleasure and relief of unpleasant feelings from smoking. RESULTS: When PDM and SDM were entered simultaneously, only PDM was related to daily cigarette count, and only SDM predicted reports of craving and relief from unpleasant feelings from smoking. SDM was associated with reports of greater pleasure from smoking and PDM was associated with lower pleasure ratings. The Fagerström Test for Nicotine Dependence (FTND) was related to daily smoking rate and craving, but WISDM composites contributed incremental prediction. CONCLUSIONS: The findings confirm that PDM indexes heavier use that is relatively unrelated to immediate consequences of smoking. SDM is not uniquely related to smoking heaviness, but is associated with craving and reports of pleasure and relief of unpleasant feelings derived from smoking during ad lib use. IMPLICATIONS: This study extends the evidence for the distinction between the WISDM PDM and SDM. PDM scores are associated with heavier smoking and are relatively unrelated to immediate consequences of smoking. SDM is more strongly related to craving and reports of smoking-derived pleasure and relief of unpleasant feelings during ongoing use in daily life.

Acute alcohol effects on set-shifting and its moderation by baseline individual differences: a latent variable analysis.

AIMS: To compare the acute effects of alcohol on set-shifting task performance (relative to sober baseline performance) during ascending and descending limb breath alcohol concentration (BrAC), as well as possible moderation of these effects by baseline individual differences. DESIGN: Shifting performance was tested during an initial baseline and a subsequent drinking session, during which participants were assigned randomly to one of three beverage conditions (alcohol, placebo or control) and one of two BrAC limb conditions [ascending and descending (A/D) or descending-only (D-only)]. SETTING: A human experimental laboratory on the University of Missouri campus in Columbia, MO, USA. PARTICIPANTS: A total of 222 moderate-drinking adults (ages 21-30 years) recruited from Columbia, MO and tested between 2010 and 2013. MEASUREMENTS: The outcome measure was performance on set-shifting tasks under the different beverage and limb conditions. Shifting performance assessed at baseline was a key moderator. FINDINGS: Although performance improved across sessions, this improvement was reduced in the alcohol compared with no-alcohol groups (post-drink latent mean comparison across groups, all Ps ≤ 0.05), and this effect was more pronounced in individuals with lower pre-drink performance (comparison of pre- to post-drink path coefficients across groups, all Ps ≤ 0.05). In the alcohol group, performance was better on descending compared with ascending limb (P ≤ 0.001), but descending limb performance did not differ across the A/D and D-only groups. CONCLUSIONS: Practising tasks before drinking moderates the acute effects of alcohol on the ability to switch between tasks. Greater impairment in shifting ability on descending compared with ascending breath alcohol concentration is not related to task practice.

Does hangover influence the time to next drink? An investigation using ecological momentary assessment.

BACKGROUND: Measures of hangover are associated with current and future problematic alcohol use. At present, it is not known whether these associations reflect any direct influence of hangover events on near-term drinking behaviors. The current study aimed to determine whether hangover following a drinking episode influences time to next drink (TTND) and, if so, to determine the direction of this effect and identify any moderating personal or contextual factors. METHODS: Community-recruited, frequent drinkers oversampled for current smoking (N = 386) carried electronic diaries for 21 days, reporting on drinking behaviors and other experiences. Survival analysis was used to model data from 2,276 drinking episodes, including 463 episodes that were followed by self-reported hangover in morning diary entries. RESULTS: When tested as the sole predictor in a survival model, hangover was associated with increased TTND. The median survival time was approximately 6 hours longer after episodes with hangovers compared to those without. In a multivariate model, hangover was only significant in the presence of interaction effects involving craving at the end of the index drinking episode and the occurrence of financial stressors. Additional predictors of TTND in the final multivariate model included age, lifetime alcohol use disorder diagnosis, typical drinking frequency, day of the week, and morning reports of craving, negative affect, and stressors after the index episode. There was no association between morning reports of hangover and contemporaneous diary ratings of likelihood of drinking later the same day. CONCLUSIONS: The findings suggest that hangover has, at best, a modest or inconsistent influence on the timing of subsequent alcohol use among frequent drinkers.

Low sensitivity to alcohol: relations with hangover occurrence and susceptibility in an ecological momentary assessment investigation.

OBJECTIVE: The current investigation tested whether low sensitivity to alcohol, as measured by the Self-Rating of the Effects of Alcohol (SRE) form, is associated with hangover occurrence or resistance, two potentially important predictors of later problematic drinking outcomes. METHOD: Drinkers who reported using alcohol at least four times in the past month (N = 402) completed the SRE at baseline and used ecological momentary assessment methods with an electronic diary to record drinking behaviors and related experiences over 21 days. Each morning, the diary assessed prior-night drinking behaviors and the presence of current hangover. RESULTS: After adjustments for sex, body weight, age, and smoking status, higher SRE scores (indicating lower alcohol sensitivity) predicted hangover occurrence on postdrinking mornings (odds ratio [OR] = 1.24 per interquartile range [IQR], p = .003). However, when the number of drinks consumed in the drinking episode was covaried, SRE scores were negatively associated with hangover (OR = 0.67 per IQR, p <.001). An interaction between SRE scores and the number of drinks consumed indicated that low-sensitivity drinkers tend to be differentially resistant to hangover at a given number of drinks. Higher SRE scores were associated with consuming more drinks on average (generalized estimating equations coefficient = 2.20 per IQR, p <.001). CONCLUSIONS: Individuals lower in alcohol sensitivity appear to be more resistant to hangovers per unit of alcohol. However, they are also more likely to engage in excessive drinking, and this may account for their increased odds of experiencing hangover during an arbitrary monitoring period. Heavy consumption, hangover resistance, and hangover frequency may each be manifestations of low sensitivity to alcohol, an established risk factor for alcohol use disorder.

Responses to alcohol and cigarette use during ecologically assessed drinking episodes.

RATIONALE: Tobacco and alcohol are frequently used together, and this may be partly explained by a distinct profile of subjective effects associated with co-administration. Ecological momentary assessment studies have examined effects of naturally occurring co-use, but, to date, have not assessed differing effects as alcohol levels rise and fall. OBJECTIVES: The objective of the study was to describe subjective states and appraisals of cigarette and alcohol effects reported during the entirety of real-world drinking episodes. METHODS: Currently-smoking frequent drinkers (N = 255) carried electronic diaries for 21 days. Analyses focused on reports made during 2,046 drinking episodes. Signaled prompts intensively oversampled moments in the hours following consumption of the first drink in an episode. Multilevel regression analyses were used to predict ratings of buzz, dizziness, excitement, and sluggishness as a function of person-level and contextual covariates, estimated blood alcohol concentration (eBAC) level, ascending vs. descending eBAC, smoking, and their interactions. Appraisals of cigarette and alcohol effects were also examined within this framework. RESULTS: Buzz, excitement, and pleasure from alcohol and cigarettes were prominent features of real-world drinking episodes. Smoking was associated with enhanced buzz and excitement when eBAC was high and descending. Smoking slightly accentuated the relation between eBAC and ratings of drinking pleasure among women, but this relation was somewhat weakened by smoking among men. CONCLUSIONS: Smoking during drinking episodes may be partly explained by a persistence of stimulant alcohol effects beyond the blood alcohol concentration peak. Acute effects of nicotine and tobacco use on the descending limb deserve further scrutiny in experimental alcohol challenge research.

Cannabinoid receptor genotype moderation of the effects of childhood physical abuse on anhedonia and depression.

CONTEXT: The endocannabinoid system has been implicated in stress adaptation and the regulation of mood in rodent studies, but few human association studies have examined these links and replications are limited. OBJECTIVES: To examine whether a synonymous polymorphism, rs1049353, in exon 4 of the gene encoding the human endocannabinoid receptor (CNR1) moderates the effect of self-reported childhood physical abuse on lifetime anhedonia and depression and to replicate this interaction in an independent sample. DESIGN, SETTING, AND PARTICIPANTS: Genetic association study in 1041 young US women with replication in an independent Australian sample of 1428 heroin-dependent individuals as cases and 506 participants as neighborhood controls. MAIN OUTCOME MEASURES: Self-reported anhedonia and depression (with anhedonia). RESULTS: In both samples, individuals who experienced childhood physical abuse were considerably more likely to report lifetime anhedonia. However, in those with 1 or more copies of the minor allele of rs1049353, this pathogenic effect of childhood physical abuse was attenuated. Thus, in participants reporting childhood physical abuse, although 57.1% of those homozygous for the major allele reported anhedonia, only 28.6% of those who were carriers of the minor allele reported it (P=.01). The rs1049353 polymorphism also buffered the effects of childhood physical abuse on major depressive disorder; however, this influence was largely attributable to anhedonic depression. These effects were also noted in an independent sample, in which minor allele carriers were at decreased risk for anhedonia even when exposed to physical abuse. CONCLUSIONS: Consistent with preclinical findings, a synonymous CNR1 polymorphism, rs1049353, is linked to the effects of stress attributable to childhood physical abuse on anhedonia and anhedonic depression. This polymorphism reportedly resides in the neighborhood of an exon splice enhancer; hence, future studies should carefully examine its effect on expression and conformational variation in CNR1, particularly in relation to stress adaptation.

Smoking desistance and personality change in emerging and young adulthood.

INTRODUCTION: We attempted to replicate and extend (Welch, P., & Poulton, R. [2009]. Personality influences on change in smoking behavior. Health Psychology, 28, 292-299. doi:10.1037/a0013471) findings regarding the relationship between smoking involvement and personality change. METHODS: Two time frames (18-25, 18-35) in a cohort of college students (N = 489 at baseline) followed for 17 years were used. Impulsivity, neuroticism, and 4 measures of smoking involvement were assessed at each time point. RESULTS: Individuals who desisted in smoking involvement tended to exhibit the largest decreases in neuroticism and impulsivity from ages 18 to 25. From ages 18 to 35, changes in smoking involvement were only significantly associated with changes in impulsivity. CONCLUSIONS: These findings add to the literature demonstrating decreasing neuroticism, and impulsivity correlates with decreased substance involvement during emerging adulthood.

The relationship between rs3779084 in the dopa decarboxylase (DDC) gene and alcohol consumption is mediated by drinking motives in regular smokers.

BACKGROUND: Motivational models of alcohol use propose that the motivation to consume alcohol is the final common pathway to its use. Both alcohol consumption and drinking motives are influenced by latent genetic factors that partially overlap. This study investigated whether drinking motives mediate the associations between alcohol consumption and 2 single-nucleotide polymorphisms (SNPs) from genes involved in serotonin (TPH2; rs1386496) and dopamine synthesis (DDC; rs3779084). Based on earlier work showing that enhancement and coping motives were heritable in regular smokers but not in nonregular smokers, we hypothesized these motives would mediate the relationships between alcohol consumption and these SNPs in regular smokers. METHODS: Drinking motives data were available from 830 young adult female twins (n = 344 regular smokers and n = 486 never/nonregular smokers). We used confirmatory factor analyses to model enhancement, coping, and alcohol consumption factors and to conduct mediation analyses in the regular smoker and never/nonregular smoker groups. RESULTS: Our hypothesis was partially supported. The relationship between alcohol consumption and rs1386496 was not mediated by drinking motives in either group. However, in the regular smokers, the relationship between alcohol consumption and rs3779084 was mediated by enhancement and coping motives. Carriers of the rs3779084 minor allele who were regular smokers reported more motivation to consume alcohol. Given this pattern of results was absent in the never/nonregular smokers, our results are consistent with a gene × smoking status interaction. CONCLUSIONS: In regular smokers, variability at the locus marked by rs3779084 in the DDC gene appears to index biologically based individual differences in the motivation to consume alcohol to attain or improve a positive affective state or to relieve a negative one. These results could be because of increased sensitivity to the reinforcing effects of alcohol among minor allele carriers who smoke, which might be due to structural or functional differences in mesorticolimic dopamine "reward" circuitry.

The subjective effects of alcohol-tobacco co-use: an ecological momentary assessment investigation.

Alcohol and tobacco use covary at multiple levels of analysis, and co-use of the 2 substances may have profound health consequences. To characterize the motivationally relevant processes contributing to co-use, the current study used ecological momentary assessment (EMA) to examine the subjective consequences of naturally occurring simultaneous use of alcohol and tobacco. Current smokers who reported frequently drinking alcohol (N=259) used electronic diaries to monitor their daily experiences for 21 days. Participants responded to prompted assessments and also initiated recordings when they smoked a cigarette or completed the first drink in a drinking episode. Momentary reports of smoking and alcohol consumption were associated with one another, and these effects remained after adjustment for occasion- and person-level covariates. When participants consumed alcohol, they reported increased pleasure and decreased punishment from the last cigarette. Smoking was associated with small increases in pleasure from the last drink. Ratings of buzzed and dizzy were synergistically affected by co-use of alcohol and tobacco. Co-use was also followed by higher levels of craving for both alcohol and tobacco. Results point to the importance of reward and incentive processes in ongoing drug use and suggest that alcohol intensifies real-time reports of the motivational consequences of smoking more strongly than smoking affects corresponding appraisals of alcohol effects.

Should the reorganization of addiction-related research across all the National Institutes of Health be structural?--The devil is truly in the details.

The recent proposal to dissolve the National Institute on Alcohol Abuse and Alcoholism and National Institute on Drug Abuse and create a new institute for substance use, abuse, and addiction will require significant effort by the staff of both institutes, the Advisory Councils, and outside experts to overcome complex challenges that could threaten its success. Although integration of the grants portfolios can be achieved, harmonization of goals and policies related to legal use of alcohol versus illegal consumption of drugs will present serious challenges. Consolidating the infrastructure of the 2 existing institutes would entail avoiding encroachment on grant funding. A new institute for substance use, abuse, and addiction would require an enormous amount of cooperation from other institutes as the portfolios of research on alcohol, tobacco, and other drug abuse should logically be transferred to the new institute. In the near term, a structural reorganization would be less efficient and more costly than the individual institutes are currently. Increasing efficiency and reducing costs over time will necessitate careful strategic planning. Success in this difficult task would be made easier and less costly by first implementing carefully placed building blocks of increasing functional reorganization. The newly created institute should increase opportunities for specialization within disorders of addiction, attract new leadership, and build a novel strategic plan that will energize scientists and staff and incorporate ideas of stakeholders to advance the public good in preventing and treating alcohol, tobacco, and all addictions. Attention must be paid to the devil in the details.

Smoking outcome expectancies in young adult female smokers: individual differences and associations with nicotine dependence in a genetically informative sample.

Outcome expectancy is a central construct in models of addiction. Several outcome expectancies associated with smoking cigarettes have been identified, and studies suggest that individual differences in smoking expectancies are related to important aspects of tobacco use, including levels of smoking, nicotine dependence and smoking cessation. In the present study, we used a novel analytic method, exploratory structural equation modeling (ESEM), to quantify smoking expectancies from a subset of items adapted from the Smoking Consequences Questionnaire (SCQ; Brandon and Baker, 1991) and SCQ-Adult (Copeland et al., 1995). In our sample of 1262 monozygotic and dizygotic young adult, female twins who were regular smokers, we quantified six smoking expectancy factors similar to those reported in previous studies. These included Negative Affect Reduction, Boredom Reduction, Weight Control, Taste Manipulation, Craving/Addiction and Stimulation-state Enhancement. We used genetic model-fitting to examine the extent to which individual differences in the expectancies were influenced by latent genetic, shared environmental and non-shared environmental factors. We also examined the validity of the expectancy factors by examining their associations with nicotine dependence (ND) before and after adjusting for comorbid diagnoses of drug dependence and alcohol use disorder. Results of the validity analysis indicated that all of the expectancies were associated with ND after covariate adjustment. Although we lacked the statistical power to distinguish between genetic and shared environmental sources of variance, our results suggest that smoking outcome expectancies aggregate in families, but the majority of variance in these expectancies is due to environmental factors specific to the individual.

Drinking motives in female smokers: factor structure, alcohol dependence, and genetic influences.

BACKGROUND: Alcohol and tobacco use often co-occur. Human and animal studies indicate that nicotine increases alcohol's rewarding effects and the motivation to consume it. The aims of this study were to examine whether the factorial architecture of self-reported motivations to consume alcohol differed between regular and nonregular cigarette smokers while taking into account the lifetime history of alcohol dependence and psychopathology, and to estimate the genetic and environmental influences on the motivations. METHODS: Using data on 2,189 monozygotic and dizygotic female twins, we examined the factorial structure (item thresholds and factor loadings, means, and variances) of the items from the Drinking Motives Questionnaire (DMQ) in regular and nonregular smokers. Post hoc tests examined the association between the latent drinking motives factors and alcohol dependence in both groups. Twin models were fitted to the latent drinking motives factors, testing for variations in the magnitude of additive genetic, shared, and nonshared environmental influences between the groups. RESULTS: The 4 DMQ factors (social, conformity, coping, and enhancement) were recovered in both groups, and their measurement structure was consistent across the groups. Regular smokers reported higher levels of coping, enhancement, and social motives while nonregular smokers reported higher conformity motives. Alcohol dependence was associated with higher scores on all motives in both groups; however, in a regression analysis that included all of the motives as predictor variables, only coping was significantly related to alcohol dependence. While twin models revealed evidence for substantially greater genetic influences on enhancement (h² = 0.40), coping (h² = 0.35) and social (h² = 0.37) drinking motives in regular compared to nonregular smokers, the power to statistically distinguish the 2 groups was low. CONCLUSIONS: While the measurement structure of the drinking motive factors appears to be similar across regular and nonregular smokers, regular smokers report more motivation to drink for internal affect-related reasons and to obtain social reward. Of all the motives, coping was the most robust predictor of alcohol dependence in both the regular and the nonregular smokers. Further, genetic influences might play a larger role in drinking motives among regular smokers, which provides tentative evidence for latent genetic × smoking status interactions.

Daily patterns of conjoint smoking and drinking in college student smokers.

Epidemiological data indicate a robust association between smoking and alcohol use. However, a critical question that is less resolved is the extent to which the smoking event takes place during the time of alcohol consumption. The present study used data from an 8-week prospective web-based study of college student smokers to examine daily associations between smoking and alcohol use, using measures of both likelihood and level of use. Findings indicated that consumption of alcohol and smoking covaried on a daily basis per person. In addition, consistent with the idea of smoking as a social activity for college students, light smokers were more likely than heavier smokers to smoke while drinking and to smoke more cigarettes while drinking. Smoking behavior among light smokers may be influenced by external social contextual cues, in contrast to heavier smokers who may be more affected by internal cues. Implications of findings for prevention work suggest the importance of targeting social situations in which smoking and drinking co-occur.

Revised NESARC personality disorder diagnoses: gender, prevalence, and comorbidity with substance dependence disorders.

We applied different diagnostic rules for diagnosing personality disorders to the NESARC epidemiological study of over 40,000 individuals. Specifically, unlike previous NESARC publications, we required that each personality disorder criterion be associated with significant distress or impairment in order to be counted toward a personality disorder (PD) diagnosis. Results demonstrated significant reductions in prevalence rates for PDs (9.1% versus 21.5% using original NESARC algorithms), and these revised prevalence rates were much more consistent with recent epidemiological studies in the U.S. and Great Britain. We also found gender differences in the prevalence rate for most PDs. Comorbidity analyses revealed strong associations between PDs and alcohol dependence, drug dependence, and tobacco dependence. PD diagnoses were also associated with scores on dysfunction and impairment, perceived stress and less social support, lifetime history of suicide attempts, interpersonal difficulties, and problems with legal authorities.

Sexual orientation and substance use trajectories in emerging adulthood.

AIMS: The current study examined developmental changes in substance use behaviors (SUBS) based upon sexual orientation. The analyses also attempted to address a number of methodological limitations in the extant longitudinal literature (i.e. distinct operationalizations of sexual orientation, timing of sexual orientation assessment with respect to reports of SUBs, non-linear growth). PARTICIPANTS: Data were drawn from a longitudinal study of incoming first-time college students at a large public university (n = 3720). DESIGN: After a paper-and-pencil assessment just prior to matriculation, participants completed a web-based survey every fall and spring for 4 years (sub-sample n = 2854). FINDINGS: Latent growth models revealed that sexual minorities demonstrated significant heterogeneity with regard to substance use trajectories. Initial levels and trajectories of the frequency of substance use for sexual minority individuals were distinct, generally, from their exclusively heterosexual peers. Methodologically, the timing of the assessment of sexual orientation influenced the results, and modeling non-linear components indicated that sexual minorities are at risk for exponential increases in their frequency of certain SUBs over time (i.e. drunkenness; cannabis use). CONCLUSIONS: Sexual minority and majority individuals exhibited differences in SUBs during emerging adulthood, especially when using self-identification to define sexual orientation. Individuals who endorsed a sexual minority self-identification at the onset of emerging adulthood, as opposed to 4 years later, evidenced exponential increases in rates of drunkenness and cannabis use. These results support that the timing of assessment is important and that some trajectories of sexual minority SUBs are non-linear during this developmental period.

Selection and socialization of risky drinking during the college transition: The importance of microenvironments associated with specific living units.

Risky drinking among college students differs as a function of living types, with living at Greek houses as a major risk factor. Both self-selection based on prior drinking and socialization through living environments have been shown to account for this association. However, it is not clear whether selection and socialization processes occur as a function of specific living units within living types. Multilevel models using a prospective sample of incoming college students (N = 2,392) demonstrated that (1) precollege drinking based selection into specific living units occurred within both fraternity houses and residence halls (beyond selection into the Greek system in general) and (2) socialization of extremely risky drinking among certain fraternity houses was greater than other houses (beyond greater socialization of living at fraternity houses than residence halls in general). Living unit-level precollege correlates (i.e., college attendance motives and cigarette use) and college correlates (i.e., peer drinking norms and alcohol availability) accounted for most of the selection and socialization effects. These findings highlight the importance of micro-environments associated with specific living units in risky drinking during the college transition.

Conjoint developmental trajectories of young adult substance use.

BACKGROUND: Despite the prominence of comorbidity among substances and the recent attention focused on trajectory-based approaches to characterizing developmental change, little research in the substance use field has simultaneously considered both course and comorbidity. METHODS: Using nationally representative panel data from the Monitoring the Future Project (MTF; n = 32,087; 56% female; 82% Caucasian), we identified developmental courses of heavy drinking, smoking, and marijuana use using 4 waves of data spanning ages 18 to 26 in a multi-cohort young adult sample. Comorbidity was examined by cross-classifying group membership in substance use trajectories. Finally, the extent to which risk factors (sex, race, alcohol expectancies, delinquency, sensation seeking, depressive affect, religiosity, academic achievement, and parent education) accounted for combinations of comorbidity that occurred at a rate greater than chance was examined. RESULTS: For each substance, we identified 4 courses of substance use that were largely consistent with those found in the literature (chronic high use, late-onset use, developmentally limited use, and low-use), with a fifth moderate smoking group. Heavy drinking, smoking, and marijuana use were each highly associated, and distinct patterns of comorbidity were evident, with greatest agreement along the diagonal. All risk factors explained comorbidity to some degree, with delinquency, sensation seeking, alcohol expectancies, and religion in particular predicting combinations of comorbidity that were characterized by early onset and chronic high use. CONCLUSIONS: Cross-substance trajectory concordance was high, with parallel changes in substance use over emerging adulthood. This suggests similar developmental timing of use, perhaps due to the experience of developmental transitions that have a common influence on use of different substances. Prediction of combinations of comorbidity characterized by early onset and persistently high use suggests that to some extent, individuals use multiple substances because of a common vulnerability to each, rather than directional relations among substances (e.g., cross-tolerance, cueing).