Risky alcohol use in adolescence: the role of genetics (DRD2, SLC6A4) and coping motives

Prospective Associations of Discrimination, Race, and Sexual Orientation with Substance Use in Adolescents

Objective: Adolescents are at high risk for alcohol and cannabis use. Emerging evidence suggests that discrimination exposure is prospectively associated with risk for alcohol use among adolescents of marginalized race, sexual orientation, or gender identity. However, it is unknown whether prospective discrimination-substance use associations among marginalized adolescents are also present for cannabis use. This study examined prospective associations of race, sexual orientation, and discrimination exposure with alcohol and cannabis use over one year. Methods: Data were drawn from a two-wave longitudinal health survey study of 9-11^th graders (n = 350 for the current analyses; Year 1 M_age=15.95 [SD = 1.07, range = 13-19]; 44% male; 44% Black, 22% White, 18% Asian, 16% Multiracial; 16% LGB; 10% Hispanic/Latinx ethnicity) at an urban high school. Two multinomial logistic regressions examined associations of Year 1 race, sexual orientation, and discrimination experiences with Year 2 alcohol and cannabis consumption separately. Results: Year 1 Discrimination exposure was associated with increased risk for Year 2 past-year alcohol use among Asian (OR = 1.34) and past-month alcohol use among Multiracial (OR = 1.30) adolescents, but not Black or LGB adolescents. Discrimination exposure was not associated with any cannabis use pattern in any group. Independent of discrimination, LGB adolescents were at greater risk for monthly alcohol (OR = 3.48) and cannabis use (OR = 4.07) at Year 2. Conclusions: Discrimination exposure is prospectively associated with risk for alcohol use among adolescents of understudied (Asian, Multiracial) racial backgrounds, and should be considered in alcohol prevention and intervention strategies. Risk factors for alcohol and cannabis use among LGB adolescents should continue to be explored.

Soft drink consumption and mental health problems: Longitudinal relations in children and adolescents

BACKGROUND

Increased soft drink consumption has been proposed as both predictor and result of mental health problems. Although possible mechanisms for both directions have been suggested, understanding of the association is limited. Most previous research has been cross-sectional and could not assess directionality.

METHOD

This study investigated the directionality of the association between soft drink consumption and mental health using longitudinal panel data of 5882 children and adolescents from the nationally representative German KiGGS baseline study (2003-2006) and KiGGS Wave 1 (2009-2012). Soft drink consumption and mental health problems were assessed by standardized questionnaire (baseline) and telephone interview (Wave 1). Four cross-lagged panel models were specified and compared regarding their fit indices. Specific paths were tested for significance.

RESULTS

Positive cross-sectional associations between soft drink consumption and mental health problems were found at both measurement points (ps < .01), even after controlling for third variables (including age, gender, and socioeconomic status). Only the lagged effect of mental health problems on soft drink consumption reached statistical significance (β = 0.031, p = .020), but not the effect in the opposite direction. The corresponding model also showed the best model fit overall.

CONCLUSIONS

Mental health problems predicted soft drink consumption over an average of six years, but not vice versa. These findings suggest that consuming soft drinks might be a dysfunctional strategy of coping with mental health problems for children and adolescents and highlight the importance of considering mental health problems in the prevention of soft drink overconsumption and obesity.

Substance use among individuals with mild intellectual disability or borderline intellectual functioning in residential care: Examining the relationship between drinking motives and substance use

Background

This study examined the relationship between substance use motives (i.e., social, conformity, coping and enhancement) and substance use in individuals with mild intellectual disability or borderline intellectual functioning (MID‐BIF).

Method

Data were collected among 163 clients with MID‐BIF using interactive questionnaires with visual cues on a tablet with a web application.

Results

Results show that social motives were positively related to frequency of alcohol use, while conformity, coping and enhancement motives were positively related to severity of alcohol use. Results for drug use show that social motives were positively related to frequency of cannabis and hard drug use and that conformity motives were negatively related to frequency of cannabis use. Coping motives were positively related to severity of drug use.

Conclusions

Insight in substance use motives should be used when adapting interventions, as it could contribute to the prevention and reduction of substance use disorders in individuals with MID‐BIF.

Different drinking motives, different adverse consequences? Evidence among adolescents from 10 European countries

INTRODUCTION AND AIM

This study, which builds on previous research demonstrating that drinking motives are associated with adverse consequences, investigates the associations between drinking motives and non-alcohol-attributed adverse consequences and disentangles alcohol-related and direct effects.

DESIGN AND METHOD

On the basis of a sample of 22 841 alcohol-using 13- to 16-year-olds (50.6% female) from Belgium, Denmark, Estonia, Finland, Ireland, Portugal, Scotland, Slovakia, Switzerland and Wales, structural equation models were used to estimate direct and indirect effects. Additionally, differences across countries were tested in a multigroup analysis.

RESULTS

The indirect effect (via alcohol use) was greater for injuries and academic problems than for more general outcomes such as life dissatisfaction and negative body image. For social, enhancement and coping motives, we found positive indirect effects (via alcohol use) on injuries and academic problems; the association was negative for conformity motives. The direct effect, that is, the effect above and beyond alcohol use, indicated more negative consequences among those who tended to drink more frequently for coping motives. More negative consequences, such as injuries and negative body image, were also found among those who drink for conformity motives. The pattern of association was largely comparable across countries.

DISCUSSION AND CONCLUSION

While the actual mean level of drinking motives, alcohol use and adverse consequence varied across countries, the consistency of association patterns implies that drinking motive-inspired health promotion efforts are likely to be beneficial across Europe. This is particularly important for coping drinkers because they are especially prone to adverse consequences over and above their alcohol use. [Wicki M, Kuntsche E, Eichenberger Y, Aasvee K, Bendtsen P, Dankulincová Veselská Z, Demetrovics Z, Dzielska A, Farkas J, de Matos MG, Roberts C, Tynjälä J, Välimaa R, Vieno A. Different drinking motives, different adverse consequences? Evidence among adolescents from 10 European countries.

Long-Term Effects of the Life Skills Program IPSY on Substance Use: Results of a 4.5-Year Longitudinal Study

This study investigated the long-term effectiveness of a Life Skills program with regard to use and proneness to legal and illicit drug use across a 4.5-year study interval. The universal school-based Life Skills program IPSY (Information + Psychosocial Competence = Protection) against adolescent substance use was implemented over 3 years (basic program in grade 5 and booster sessions in grades 6 and 7). Over the same time period, it was evaluated based on a longitudinal quasi-experimental design with intervention and control group, including two follow-up assessments after program completion [six measurement points; N (T1) = 1657 German students; M age (T1) = 10.5 years]. Applying an HLM approach, results showed that participation in IPSY had a significant effect on the frequency of smoking, and proneness to illicit drug use, across the entire study period. In addition, shorter-term effects were found for the frequency of alcohol use in that intervention effects were evident until the end of program implementation but diminished 2 years later. Thus, IPSY can be deemed an effective intervention against tobacco use and proneness to and use of illicit drugs during adolescence; however, further booster sessions may be necessary in later adolescence to enhance youths' resistance skills when alcohol use becomes highly normative among peers.

Metabolomics of Neurotransmitters and Related Metabolites in Post-Mortem Tissue from the Dorsal and Ventral Striatum of Alcoholic Human Brain

We report on changes in neurotransmitter metabolome and protein expression in the striatum of humans exposed to heavy long-term consumption of alcohol. Extracts from post mortem striatal tissue (dorsal striatum; DS comprising caudate nucleus; CN and putamen; P and ventral striatum; VS constituted by nucleus accumbens; NAc) were analysed by high performance liquid chromatography coupled with tandem mass spectrometry. Proteomics was studied in CN by two-dimensional gel electrophoresis followed by mass-spectrometry. Proteomics identified 25 unique molecules expressed differently by the alcohol-affected tissue. Two were dopamine-related proteins and one a GABA-synthesizing enzyme GAD65. Two proteins that are related to apoptosis and/or neuronal loss (BiD and amyloid-β A4 precursor protein-binding family B member 3) were increased. There were no differences in the levels of dopamine (DA), 3,4-dihydrophenylacetic acid (DOPAC), serotonin (5HT), homovanillic acid (HVA), 5-hydroxyindoleacetic acid (HIAA), histamine, L-glutamate (Glu), γ-aminobutyric acid (GABA), tyrosine (Tyr) and tryptophan (Tryp) between the DS (CN and P) and VS (NAc) in control brains. Choline (Ch) and acetylcholine (Ach) were higher and norepinephrine (NE) lower, in the VS. Alcoholic striata had lower levels of neurotransmitters except for Glu (30 % higher in the alcoholic ventral striatum). Ratios of DOPAC/DA and HIAA/5HT were higher in alcoholic striatum indicating an increase in the DA and 5HT turnover. Glutathione was significantly reduced in all three regions of alcohol-affected striatum. We conclude that neurotransmitter systems in both the DS (CN and P) and the VS (NAc) were significantly influenced by long-term heavy alcohol intake associated with alcoholism.

Allelic Variation of Risk for Anxiety Symptoms Moderates the Relation Between Adolescent Safety Behaviors and Social Anxiety Symptoms

Social anxiety often develops in adolescence, and precedes the onset of depression and substance use disorders. The link between social anxiety and use of behaviors to minimize distress in social situations (i.e., safety behaviors) is strong and for some patients, this link poses difficulty for engaging in, and benefiting from, exposure-based treatment. Yet, little is known about whether individual differences may moderate links between social anxiety and safety behaviors, namely variations in genetic alleles germane to anxiety. We examined the relation between adolescent social anxiety and expressions of safety behaviors, and whether allelic variation for anxiety moderates this relation. Adolescents (n=75; ages 14-17) were recruited from two larger studies investigating measurement of family relationships or adolescent social anxiety. Adolescents completed self-report measures about social anxiety symptoms and use of safety behaviors. They also provided saliva samples to assess allelic variations for anxiety from two genetic polymorphisms (BDNF rs6265; TAQ1A rs1800497). Controlling for adolescent age and gender, we observed a significant interaction between social anxiety symptoms and allelic variation (β=0.37, t=2.41, p=.02). Specifically, adolescents carrying allelic variations for anxiety evidenced a statistically significant and relatively strong positive relation between social anxiety symptoms and safety behaviors (β=0.73), whereas adolescents not carrying allelic variation evidenced a statistically non-significant and relatively weak relation (β=0.22). These findings have important implications for treating adolescent social anxiety, in that we identified an individual difference variable that can be used to identify people who evidence a particularly strong link between use of safety behaviors and expressing social anxiety.

When abuse primes addiction - automatic activation of alcohol concepts by child maltreatment related cues in emotionally abused alcoholics

INTRODUCTION

Recent research indicates that there is a link between emotional maltreatment and alcohol dependence (AD), but the underlying mechanisms still need to be clarified. There is reason to assume that maltreatment related cues automatically activate an associative memory network comprising cues eliciting craving as well as alcohol-related responses. The current study aimed to examine this network in AD patients who experienced emotional abuse using a priming paradigm.

METHODS

A specific priming effect in emotionally abused AD subjects was hypothesized for maltreatment related words that preceded alcohol related words. 49 AD subjects (n=14 with emotional abuse vs. n=35 without emotional abuse) and 34 control subjects performed a priming task with maltreatment related and neutral prime words combined with alcohol related and neutral target words. Maltreatment related words consisted of socially and physically threatening words.

RESULTS

As hypothesized, a specific priming effect for socially threatening and physically threatening cues was found only in AD subjects with emotional abuse.

CONCLUSIONS

The present data are the first to provide evidence that child maltreatment related cues automatically activate an associative memory network in alcoholics with emotional abuse experiences.

[Duration of therapeutic remission alcohol dependence: a role of dopamine system genes polymorphism and family history density]

AIM

A quantitative assessment of the impact of genetic factors (density of family history of alcohol dependence and dopamine system genes polymorphisms) on the average time to relapse (ATR) after alcohol dependence treatment (duration of therapeutic remission from alcohol dependence).

MATERIAL AND METHODS

Authors studied 247 male Russian inpatients diagnosed with ICD-10 F10.2 who had at least two therapeutic remissions before the current hospitalization and 259 healthy controls. ATR and the density of family history of alcohol dependence were evaluated retrospectively according to the clinical interview.

RESULTS AND CONCLUSION

The high density of family history (at least 2 people with alcohol problems among the blood relatives) and some dopamine system genes polymorphisms significantly affect the average time to relapse. An allele A9 of the dopamine transporter gene (DAT VNTR 40 bp) was associated (p=0.003; OR=1.73) with short (up to 12 months) average time to relapse. A trend toward association (p=0.052) was noted for dopamine receptor type 2 gene polymorphisms (rs1800497, rs6275). Patients with long-term ATR are genetically different from patients with short ATR by the set of variants of tyrosine hydroxylase gene (HUMTH01, p=0.002; OR=3.08) and from the control group by the genotype LH of the catechol-O-methyltransferase gene (rs4680, p=0.02; OR=2.33). Some other sets of HUMTH01 variants (p=0.0001; OR=2.38) and the dopamine receptor type 4 (DRD4 VNTR 48 bp, p=0.055) may have protective properties with regard to short ATR. Polymorphisms (rs1108580, rs1611115) of the dopamine-beta-hydroxylase gene were not related to the ATR.

Neurotransmitters in alcoholism: A review of neurobiological and genetic studies

Recent advances in the study of alcoholism have thrown light on the involvement of various neurotransmitters in the phenomenon of alcohol addiction. Various neurotransmitters have been implicated in alcohol addiction due to their imbalance in the brain, which could be either due to their excess activity or inhibition. This review paper aims to consolidate and to summarize some of the recent papers which have been published in this regard. The review paper will give an overview of the neurobiology of alcohol addiction, followed by detailed reviews of some of the recent papers published in the context of the genetics of alcohol addiction. Furthermore, the author hopes that the present text will be found useful to novices and experts alike in the field of neurotransmitters in alcoholism.

Chronic alcohol disrupts dopamine receptor activity and the cognitive function of the medial prefrontal cortex

Dopamine (DA) receptors in the medial prefrontal cortex (mPFC) exert powerful effects on cognition by modulating the balance between excitatory and inhibitory neurotransmission. The present study examined the impact of chronic intermittent ethanol (CIE) exposure on cognitive function and DA receptor-mediated neurotransmission in the rat mPFC. Consistent with alterations in executive function in alcoholics, CIE-exposed rats exhibited deficits in behavioral flexibility in an operant set-shifting task. Since alterations in dopaminergic neurotransmission in the mPFC have been implicated in a number of behavioral disorders including addiction, studies were then performed in the adult acute slice preparation to examine changes in DA receptor function in the mPFC following CIE exposure. In slices obtained from control rats, DA receptor stimulation was observed to exert complex actions on neuronal firing and synaptic neurotransmission that were not only dependent upon the particular receptor subtype but also whether it was a pyramidal cell or a fast-spiking interneuron. In contrast to slices from control rats, there was a near complete loss of the modulatory actions of D2/D4 receptors on cell firing and neurotransmission in slices obtained immediately, 1 and 4 weeks after the last day of CIE exposure. This loss did not appear to be associated with changes in receptor expression. In contrast, CIE exposure did not alter D1 receptor function or mGluR1 modulation of firing. These studies are consistent with the suggestion that chronic alcohol exposure disrupts cognitive function at least in part through disruption of D2 and D4 receptor signaling in mPFC.

A systematic review of genetic influences on coping

Coping refers to the way that an individual manages stress. Coping strategies vary; for example, problem-focused coping is directed at reducing or removing a stressor, while emotion-focused coping is directed more at managing reactions that accompany the stressor. How individuals cope with stress can impact their health, but the physiological effects of coping are not well understood. The field of genetics provides tools that could help illuminate the physiology of coping. This review of the literature was conducted to determine what is currently known about the phenotype of coping from a genetic perspective. PubMed, HubMed, PsychInfo, Medline, Scopus, and Google Scholar databases were used to conduct the search, and reference lists were reviewed to identify additional publications. Only studies that measured coping style or a coping domain specifically, were written in English language, and were human-subject focused were included in the review. We identified 19 studies that met these criteria, and 2 types of genetic studies emerged for the review: heritability (n = 9) and candidate gene association (n = 10) studies. Heritability estimates of .68-.76 support a nonadditive genetic component to coping. Replication of association was found for the serotonin transporter and adrenergic receptor beta 2 genes. In addition to finding evidence supporting a role for genetic variability with coping phenotype, it is worth noting that the review revealed a lack of consistency in instruments used to phenotype coping across studies.

Mediational relations of substance use risk profiles, alcohol-related outcomes, and drinking motives among young adolescents in the Netherlands

AIM

To examine the mediation by drinking motives of the association between personality traits (negative thinking, anxiety sensitivity, impulsivity, and sensation seeking) and alcohol frequency, binge drinking, and alcohol-related problems using a sample of students (n=3053) aged between 13 and 15, who reported lifetime use of alcohol.

METHOD

Structural equation modeling was used to examine the relationship between personality traits and alcohol-related outcomes. The Model Indirect approach was used to examine the hypothesized mediation by drinking motives of the association between personality traits and alcohol-related outcomes.

RESULTS

In this study among young adolescents, coping motives, social motives and enhancement motives played a prominent mediating role between personality and the alcohol outcomes. Multi-group analyses revealed that the role of drinking motives in the relation between personality and alcohol outcomes were largely similar between the sexes, though there were some differences found for binge drinking. More specifically, for young males, enhancement motives seems to play a more prominent mediation role between personality and binge drinking, while for young females, coping motives play a more mediating role between personality and binge drinking. Few mediation associations were found for conformity motives, and no relationships were found between anxiety sensitivity and drinking motives.

DISCUSSION

Already in early adolescence, personality traits are found to be associated with drinking motives, which in turn are related to alcohol use. This study provides indications that it is important to intervene in early adolescence with interventions focusing on personality traits in combination with drinking motives.

The association between DRD2/ANKK1 and genetically informed measures of alcohol use and problems

In 1990, Blum and colleagues first reported an association between DRD2 and alcoholism. While there have been subsequent replications of this genetic association, there have also been numerous studies that failed to detect an association between DRD2 and alcohol dependence. We propose that one aspect contributing to this inconsistency is the variation in alcohol phenotype used across studies. Within the population-based Finnish twin sample, FinnTwin16, we previously performed multivariate twin analyses to extract latent genetic factors, which account for the variation across seven measures of alcohol consumption (frequency of drinking, frequency × quantity, frequency of heavy drinking, frequency of intoxication and maximum drinks in a 24-hour period) and problems (the Rutgers Alcohol Problem Index-RAPI and the Mälmö-modified Michigan Alcohol Screen Test-MmMAST) in 3065 twins. In the present study, we examined the association between 31 DRD2/ANKK1 single-nucleotide polymorphisms (SNPs) and the genetic factor scores generated by twin analyses in a subset of FinnTwin16 (n = 602). We focus on two of the genetic factors: a general alcohol consumption and problems factor score, which represents shared genetic variance across alcohol measures, and a alcohol problems genetic factor score, which loads onto the two indices of problematic drinking (MAST and RAPI). After correction for multiple testing across SNPs and phenotypes, of the 31 SNPs genotyped across DRD2/ANKK1, one SNP (rs10891549) showed significant association with the general alcohol consumption and problems factor score (P = 0.004), and four SNPs (rs10891549, rs1554929, rs6275, rs6279), representing two independent signals after accounting for linkage disequilibrium, showed significant association with the alcohol problems genetic factor score (P = 0.005, P = 0.005, P = 0.003, P = 0.003). In this study, we provide additional positive evidence for the association between DRD2/ANKK1 and alcohol outcomes, including frequency of drinking and drinking problems. Additionally, post hoc analyses indicate stronger association signals using genetic factor scores than individual measures, which suggest that accounting for the genetic architecture of the alcohol measures reduces genetic heterogeneity in alcohol dependence outcomes in this sample and enhances the ability to detect association.

Longitudinal associations between attitudes towards binge drinking and alcohol-free drinks, and binge drinking behavior in adolescence

Alcohol attitudes are often considered an important predecessor of drinking behavior, although the literature is equivocal. Lately, attention has turned to enhancing positive cognitions on alcoholic-free drinks to discourage heavy drinking. The current study was the first to longitudinally examine associations between attitudes towards binge drinking and alcohol-free drinks and binge drinking behavior in a cross-lagged path model in Mplus. Participants were 293 adolescents (131 boys, M(age)=16.1 years) who filled in two online questionnaires with a six-month interval. Binge drinking behavior and attitudes towards binge drinking and alcohol-free drinks were all significantly correlated at both waves. The multivariate model, however, showed that only higher levels of binge drinking at T1 were prospectively related to more positive binge drinking attitudes at T2, and not vice versa. Analyses were controlled for sex, educational level, and age. Findings discard the Theory of Planned Behavior, but rather seem consistent with the Theory of Cognitive Dissonance, i.e., adolescents may adapt their cognitions to their behavior. More longitudinal research with several time points and over a longer period of time is needed to further examine the development of attitudes and drinking behavior.

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.

Actin polymerization machinery: the finish line of signaling networks, the starting point of cellular movement

Dynamic assembly of actin filaments generates the forces supporting cell motility. Several recent biochemical and genetic studies have revealed a plethora of different actin binding proteins whose coordinated activity regulates the turnover of actin filaments, thus controlling a variety of actin-based processes, including cell migration. Additionally, emerging evidence is highlighting a scenario whereby the same basic set of actin regulatory proteins is also the convergent node of different signaling pathways emanating from extracellular stimuli, like those from receptor tyrosine kinases. Here, we will focus on the molecular mechanisms of how the machinery of actin polymerization functions and is regulated, in a signaling-dependent mode, to generate site-directed actin assembly leading to cell motility.