Adolescent Binge Drinking Research Articles

The persistence of adolescent binge drinking into adulthood: findings from a 15-year prospective cohort study

ObjectivesTo examine the prevalence of binge drinking in adolescence and its persistence into adulthood in an Australian cohort.Design15-year prospective cohort study.SettingVictoria, Australia.Participants1943 adolescents were recruited from secondary schools at age...

Relationship between adolescent binge drinking and childhood alcohol use

In this issue of The Journal, Sanchez et al from the Universidade Federal de São Paulo have evaluated the hypothesis that childhood alcohol use may predict adolescent binge drinking in more than 17 000 high school students in Brazil. Logistic regression testing was used to evaluate the relationship between the first alcohol use and adolescent binge drinking. Adolescents who first used alcohol during childhood, as compared with those who only used alcohol at later stages, were more likely to engage in binge-drinking behaviors. They also had a pattern of heavy alcohol use and recent use of illegal drugs. The authors conclude that childhood alcohol use is a risk factor for the most dangerous patterns of alcohol use in adolescence, also noting an association with parental alcohol use. Article page 363▶ Childhood Alcohol Use May Predict Adolescent Binge Drinking: A Multivariate Analysis among Adolescents in BrazilThe Journal of PediatricsVol. 163Issue 2PreviewTo test the hypothesis that first alcohol use during childhood is associated with heavy drinking patterns during adolescence and with parental drinking patterns and parental rules about alcohol consumption. Full-Text PDF

Increased receptor for advanced glycation end product expression in the human alcoholic prefrontal cortex is linked to adolescent drinking

Adolescence is characterized behaviorally by increased impulsivity and risk-taking that declines in parallel with maturation of the prefrontal cortex and executive function. In the brain, the receptor for advanced glycation end products (RAGE) is critically involved in neurodevelopment and neuropathology. In humans, the risk of alcoholism is greatly increased in those who begin drinking between 13 and 15years of age, and adolescents binge drink more than any other age group. We have previously found that alcoholism is associated with increased expression of neuroimmune genes. This manuscript tested the hypothesis that adolescent binge drinking upregulates RAGE and Toll-like receptor (TLR) 4 as well as their endogenous agonist, high-mobility group box 1 (HMGB1). Immunohistochemistry, Western blot, and mRNA analyses found that RAGE expression was increased in the human post-mortem alcoholic orbitofrontal cortex (OFC). Further, an earlier age of drinking onset correlated with increased expression of RAGE, TLR4, and HMGB1. To determine if alcohol contributed to these changes, we used an adolescent binge ethanol model in rats (5.0g/kg, i.g., 2-day on/2-day off from postnatal day [P] 25 to P55) and assessed neuroimmune gene expression. We found an age-associated decline of RAGE expression from late adolescence (P56) to young adulthood (P80). Adolescent intermittent ethanol exposure did not alter RAGE expression at P56, but increased RAGE in the young adult PFC (P80). Adolescent intermittent ethanol exposure also increased TLR4 and HMGB1 expression at P56 that persisted into young adulthood (P80). Assessment of young adult frontal cortex mRNA (RT-PCR) found increased expression of proinflammatory cytokines, oxidases, and neuroimmune agonists at P80, 25days after ethanol treatment. Together, these human and animal data support the hypothesis that an early age of drinking onset upregulates RAGE/TLR4-HMGB1 and other neuroimmune genes that persist into young adulthood and could contribute to risk of alcoholism or other brain diseases associated with neuroinflammation.

Abnormal affective decision making revealed in adolescent binge drinkers using a functional magnetic resonance imaging study.

The goal of this study was to investigate the neural correlates of affective decision making, as measured by the Iowa Gambling Task (IGT), which are associated with adolescent binge drinking. Fourteen adolescent binge drinkers (16-18 years of age) and 14 age-matched adolescents who had never consumed alcohol--never drinkers--were recruited from local high schools in Chengdu, China. Questionnaires were used to assess academic performance, drinking experience, and urgency. Brain regions activated by the IGT performance were identified with functional magnetic resonance imaging. Results showed that, compared to never drinkers, binge drinkers performed worse on the IGT and showed higher activity in the subcomponents of the decision-making neural circuitry implicated in the execution of emotional and incentive-related behaviors, namely, the left amygdala and insula bilaterally. Moreover, measures of the severity of drinking problems in real life, as well as high urgency scores, were associated with increased activity within the insula, combined with decreased activity within the orbitofrontal cortex. These results suggest that hyperreactivity of a neural system implicated in the execution of emotional and incentive-related behaviors can be associated with socially undesirable behaviors, such as binge drinking, among adolescents. These findings have social implications because they potentially reveal underlying neural mechanisms for making poor decisions, which may increase an individual's risk and vulnerability for alcoholism.

The Impact of Adolescent Binge Drinking and Sustained Abstinence on Affective State

While it is clear that affect is negatively impacted by heavy drinking in adulthood and that it improves with abstinence, little is known about effects of heavy drinking on mood during adolescence. This study examined negative mood states among 2 groups of 16- to 18-year-old high school students; youth with a history of recent heavy episodic drinking (HED; n = 39) and comparison youth with limited lifetime drinking experience (CON; n = 26). Affect was assessed at 3 time points during a 4- to 6-week period of monitored abstinence using the Hamilton Rating Scales for Anxiety and Depression; self-reports were obtained with the state portion of the State-Trait Anxiety Inventory, and experience sampling of current affect was assessed via daily text messages sent at randomly determined times in the morning, afternoon, and evening. Youth with a recent history of HED reported more negative affect compared with nondrinking youth during early stages of abstinence (days since last HED at assessment 1: M = 6.46; SD = 5.06); however, differences in affect were not observed after 4 to 6 weeks of abstinence. Sex differences were evident, with HED girls reporting greater depression and anxiety than HED male peers. Although not significant, response patterns indicated that boys may experience faster resolution of negative emotional states than girls with sustained abstinence. Findings suggest that high-dose drinking is associated with elevated negative affect for adolescents and that negative mood states may take longer to resolve for girls than for boys following heavy drinking episodes. Future research clarifying naturally occurring changes in affective response during early and sustained abstinence is necessary for improving programs designed to promote adolescent decision-making and to reduce risk for relapse.

Childhood Alcohol Use May Predict Adolescent Binge Drinking: A Multivariate Analysis among Adolescents in Brazil

To test the hypothesis that first alcohol use during childhood is associated with heavy drinking patterns during adolescence and with parental drinking patterns and parental rules about alcohol consumption. A national cross-sectional survey of 17,371 high-school students. Students were drawn from 789 public and private schools in all the Brazilian state capitals using a multistage probabilistic sampling method and a self-report questionnaire. Weighted data were analyzed through logistic regression testing for differences on the associated factors for first use of alcohol during childhood. Survival analysis and Cox proportional hazard models were used to confirm results. Among the 82% alcohol lifetime users, 11% had first used alcohol before age 12 years. The lack of perception of possible punishment by parents is associated with childhood alcohol use (OR 2.22, 95% CI 1.67-2.95). Adolescents who first used alcohol during childhood compared with those who only used alcohol at later ages are more likely to engage in binge drinking behaviors (OR 1.57, 95% CI 1.17-2.10), to have a pattern of heavy alcohol use (OR 1.98, 95% CI 1.26-3.09), and to have recently used illegal drugs (OR 1.74, 95% CI 1.39-2.16). According to hazard ratios, students with an earlier age of onset were more likely to have used tobacco and any illegal drug in the past year. Childhood alcohol may be a risk factor for the most dangerous patterns of alcohol use in adolescence and is associated with parental alcohol use. Parental rules about child alcohol use must be clear because perception of punishment might delay the age of first alcohol use.

Underage binge drinking adolescents: sociodemographic profile and utilization of family doctors.

Context. Binge drinking (more than five drinks on one occasion) is a major public health problem among teenagers in the US, Canada, and Europe. Negative outcomes to binge drinking include alcohol related injuries and accidental death. Family physicians are the main point of contact between binging adolescents and the health care system. Design and Setting. This study was based on a secondary analysis of 6,607 respondents aged 15–17 from the regionally representative data acquired through the Canadian Community Health Survey 1.1. Results. According to our findings, one in every eight teens aged 15–17 binge drank monthly. The odds of binge drinking were higher among males, Whites, those living away from parents, teens who reported a decline in health status, and those experiencing back problems and depression. Smoking status was strongly associated with the binge drinking behavior. Three-quarters of binge drinking adolescents had seen their family doctor in the past year but only one in ten had spoken with any health professional about a mental health issue. Conclusions. Family physicians need to screen their adolescent patients for binge drinking in order to provide timely and effective interventions. Awareness of the profile of binge drinkers could improve the accuracy of targeting and outreaching strategies.

Changes in the Innate Immune Responses by Intermittent Ethanol Consumption May Influence Cognition in Susceptible Adolescent Binge Drinkers

Binge drinking is an increasing social problem, particularly in adolescents. Cognitive deficits may occur as a result of such drinking patterns, although the biochemical processes involved in such changes are unclear. Recent studies in a rat model of binge drinking have shown that the innate immune system is activated in both the periphery and a specific brain region, the hippocampus. It was therefore of interest to ascertain whether a) inflammatory markers were present in the blood of University students, N=24, identified as binge drinkers for at least 2 years, and b) whether cognitive function was impaired, by comparison to controls, N=24. There was a significantly increased mean plasma TNFα value in male binge drinkers by comparison to controls, P>0.007, while the female binge drinkers showed a significantly lower mean value for TNFα, A¯Â€Â P<0.05,A¯Â€Â¬ by comparison to controls. An inflammatory profile, as assessed by increased plasma values of IL-6, was evident in binge drinkers, although the values did not reach significance. Although there were significant differences between the controls and binge drinking individuals with respect to the Trail-Making test and semantic fluency, both of which were increased, (possibly indicating a compensation mechanism), no gross neuropsychological changes were identified in the binge drinking group. This may relate to the fact that such individuals were University students with high cognitive capacity. Continued activation of the innate immune system in such ‘binge drinking’ individuals may ultimately contribute to neuropsychiatric deficits.

Alcohol intoxications during adolescence increase motivation for alcohol in adult rats and induce neuroadaptations in the nucleus accumbens

Adolescent alcohol binge drinking constitutes a major vulnerability factor to develop alcoholism. However, mechanisms underlying this susceptibility remain unknown. We evaluated the effect of adolescent binge-like ethanol intoxication on vulnerability to alcohol abuse in Sprague–Dawley rats. To model binge-like ethanol intoxication, every 2 days, rats received an ethanol injection (3.0 g/kg) for 2 consecutive days across 14 days either from postnatal day 30 (PND30) to 43 (early adolescence) or from PND 45 to PND 58 (late adolescence). In young adult animals, we measured free ethanol consumption in the two-bottle choice paradigm, motivation for ethanol in the operant self-administration task and both ethanol's rewarding and aversive properties in the conditioned place preference (CPP) and taste aversion (CTA) paradigms. While intermittent ethanol intoxications (IEI) during late adolescence had no effect on free-choice 10% ethanol consumption, we found that IEI during early adolescence promoted free-choice 10% ethanol consumption, enhanced motivation for ethanol in the self-administration paradigm and induced a loss of both ethanol-induced CPP and CTA in young adults. No modification in either sucrose self-administration or amphetamine-induced CPP was observed. As the nucleus accumbens (Nac) is particularly involved in addictive behavior, we analyzed IEI-induced long-term neuroadaptations in the Nac using c-Fos immunohistochemistry and an array of neurotransmission-related genes. This vulnerability to ethanol abuse was associated with a lower c-Fos immunoreactivity in the Nac and enduring alterations of the expression of Penk and Slc6a4, 2 neurotransmission-related genes that have been shown to play critical roles in the behavioral effects of ethanol and alcoholism.

Binge drinking among adolescents in Russia: Prevalence, risk and protective factors

Despite evidence that alcohol misuse has been having an increasingly detrimental effect on adolescent wellbeing in Russia in recent years this phenomenon has been little researched. Using data from 2112 children from the Arkhangelsk Social and Health Assessment (SAHA) 2003, this study examined which factors acted as ‘risk’ or ‘protective’ factors for adolescent binge drinking within three domains we termed the ‘family environment’, the ‘alcohol environment’ and ‘deviant behaviour’. The results showed that in the presence of comparatively moderate levels of binge drinking among both boys and girls, being able to access alcohol easily, being unaware of the risks of binge drinking and having peers who consumed alcohol increased the risk of adolescent binge drinking — as did playing truant, smoking and marijuana use, while parental warmth was protective against binge drinking for girls. Our finding that risk and protective factors occur across domains suggests that any interventions targeted against adolescent binge drinking may need to simultaneously focus on risk behaviours in different domains, while at the same time, broader social policy should act to limit the availability of alcohol to adolescents in Russia more generally.

Recent binge drinking predicts smaller cerebellar volumes in adolescents

The current study examined the effects of recent binge drinking on cerebellar morphometry in a sample of healthy adolescents. Participants were 106 teenagers (46 bingers and 60 controls) aged 16–19 who received a high-resolution magnetic resonance imaging (MRI) scan. FreeSurfer segmented and quantified the volume of each cerebellum. Maximum drinks during a binge in the past 3 months and duration since last binge were examined as predictors of cerebellar volume, after controlling for potentially confounding variables. In the 106 teens, higher peak drinks predicted smaller left hemisphere cerebellar gray and whitematter, and right hemisphere cerebellar gray matter, and marginally predicted smaller right hemisphere cerebellar white matter. Gender did not moderate these effects. More intense adolescent binge drinking is linked to smaller cerebellar volumes even in healthy teens, above and beyond variability attributable to risk factors for binge drinking. Longitudinal research is needed to see if cerebellar volumes worsen with protracted drinking and recover with abstinence. Interventions aimed at improving brain structure in adolescent binge drinkers are necessary given the high prevalence of risky drinking in youth.

Adolescent binge drinking increases expression of the danger signal receptor agonist HMGB1 and toll-like receptors in the adult prefrontal cortex

Adolescence is a critical developmental stage of life during which the prefrontal cortex (PFC) matures, and binge drinking and alcohol abuse are common. Recent studies have found that ethanol increases neuroinflammation via upregulated high-mobility group box 1 (HMGB1) signaling through Toll-like receptors (TLRs). HMGB1/TLR ‘danger signaling’ induces multiple brain innate immune genes that could alter brain function. To determine whether adolescent binge drinking persistently increases innate immune gene expression in the PFC, rats (P25–P55) were exposed to adolescent intermittent ethanol (AIE [5.0g/kg, 2-day on/2-day off schedule]). On P56, HMGB1/TLR danger signaling was assessed using immunohistochemistry (i.e., +immunoreactivity [+IR]). In a separate group of subjects, spatial and reversal learning on the Barnes maze was assessed in early adulthood (P64–P75), and HMGB1/TLR danger signaling was measured using immunohistochemistry for +IR and RT-PCR for mRNA in adulthood (P80). Immunohistochemical assessment at P56 and 24days later at P80 revealed increased frontal cortical HMGB1, TLR4, and TLR3 in the AIE-treated rats. Adolescent intermittent ethanol treatment did not alter adult spatial learning on the Barnes maze, but did cause reversal learning deficits and increased perseverative behavior. Barnes maze deficits correlated with the expression of danger signal receptors in the PFC. Taken together, these findings provide evidence that adolescent binge drinking leads to persistent upregulation of innate immune danger signaling in the adult PFC that correlates with adult neurocognitive dysfunction.

Substance use and sexual behavior among recent Hispanic immigrant adolescents: Effects of parent–adolescent differential acculturation and communication

ObjectivesTo ascertain the effects of parent–adolescent acculturation gaps, perceived discrimination, and perceived negative context of reception on adolescent cigarette smoking, alcohol use, sexual activity, and sexual risk taking. We used an expanded, multidimensional model of acculturation. MethodA sample of 302 recently immigrated parent–adolescent dyads (152 from Miami and 150 from Los Angeles) completed measures of acculturation (Hispanic and American practices and identifications, and individualist and collectivist values) and parent–adolescent communication. Adolescents completed measures of recent cigarette smoking, alcohol use, sexual behavior, and sexual risk taking. ResultsParent–adolescent gaps in American practices and ethnic identity, and perceptions of a negative context of reception, predicted compromised parent–adolescent communication. In Miami only, adolescent-reported communication negatively predicted odds of cigarette smoking, occasions of drunkenness, and number of sexual partners. Also in Miami only, parent-reported communication positively predicted these outcomes, as well as occasions of adolescent binge drinking, drunkenness, number of sexual partners, and odds of unprotected sex. The only significant findings in Los Angeles were protective effects of parent-reported communication on frequency of alcohol use and of binge drinking. Mediational effects emerged only in the Miami sample. ConclusionsEffects of parent–adolescent acculturation gaps vary across Hispanic groups and receiving contexts. The especially strong parental control in many Mexican families may account for these differences. However, other important differences between Hispanic subgroups and communities of reception could also account for these differences. Prevention efforts might encourage Hispanic youth both to retain their culture of origin and to acquire American culture.

ADOLESCENT ESTIMATION OF PEER SUBSTANCE USE: WHY IT MATTERS

ADOLESCENT ESTIMATION OF PEER SUBSTANCE USE: WHY IT MATTERS

Predictors of binge drinking in adolescents: ultimate and distal factors - a representative study

BackgroundAs epidemiological surveys have shown, binge drinking is a constant and wide-spread problem behavior in adolescents. It is not rare to find that more than half of all adolescents engage in this behavior when assessing only the last 4 weeks of time independent of the urbanity of the region they live in. There have been several reviews on predictors of substance consumption in adolescents in general, but there has been less high quality research on predictors of binge drinking, and most studies have not been theoretically based. The current study aimed to analyze the ultimate and distal factors predicting substance consumption according to Petraitis' theory of triadic influence. We assessed the predictive value of these factors with respect to binge drinking in German adolescents, including the identification of influence direction.MethodsIn the years 2007/2008, a representative written survey of N = 44,610 students in the 9th grade of different school types in Germany was carried out (net sample). The return rate of questionnaires was 88% regarding all students whose teachers or school directors had agreed to participate in the study. In this survey, prevalence of binge drinking was investigated as well as potential predictors from the social/interpersonal, the attitudinal/environmental, and the intrapersonal fields (3 factors of Petraitis). In a multivariate logistic regression analysis, these variables were included after testing for multicollinearity in order to assess their ability to predict binge drinking.ResultsPrevalence of binge drinking in the last 30 days was 52.3% for the surveyed adolescents with a higher prevalence for boys (56.9%) than for girls (47.5%). The two most influential factors found to protect against binge drinking with p < .001 were low economic status and importance of religion. The four most relevant risk factors for binge drinking (p < .001) were life-time prevalence of school absenteeism/truancy, academic failure, suicidal thoughts, and violence at school in the form of aggressive behavior of teachers. The model of Petraitis was partly confirmed for Binge Drinking in German adolescents and the direction of influence factors was clarified.ConclusionsWhereas some of the risk and protective factors for binge drinking are not surprising since they are known for substance abuse in general, there are two points that could be targeted in interventions that do not focus on adolescents alone: (a) training teachers in positive, reassuring behavior and constructive criticism and (b) a focus on high risk adolescents either because they have a lack of coping strategies when in a negative mood or because of their low academic achievement in combination with absenteeism from school.

Alcohol Consumption in Movies and Adolescent Binge Drinking in 6 European Countries

The goal of this study was to investigate whether the association between exposure to images of alcohol use in movies and binge drinking among adolescents is independent of cultural context. A cross-sectional survey study in 6 European countries (Germany, Iceland, Italy, Netherlands, Poland, and Scotland) was conducted. A total of 16 551 pupils from 114 public schools with a mean (± SD) age of 13.4 (± 1.18) years participated. By using previously validated methods, exposure to alcohol use in movies was estimated from the 250 top-grossing movies of each country (years 2004-2009). Lifetime binge drinking was the main outcome measure. Overall, 27% of the sample had consumed >5 drinks on at least 1 occasion in their life. After controlling for age, gender, family affluence, school performance, television screen time, sensation seeking and rebelliousness, and frequency of drinking of peers, parents, and siblings, the adjusted β-coefficient for lifetime binge drinking in the entire sample was 0.12 (95% confidence interval: 0.10-0.14; P < .001). The crude relationship between movie alcohol use exposure and lifetime binge drinking was significant in all countries; after covariate adjustment, the relationship was still significant in 5 of 6 countries. A sensitivity analysis revealed that the association is content specific, as there was no significant association between lifetime binge drinking and exposure to smoking in movies. The link between alcohol use in movies and adolescent binge drinking was robust and seems relatively unaffected by cultural contexts.

An Examination of Pathways from Childhood Maltreatment to Adolescent Binge Drinking

Considerable clinical and empirical evidence has accumulated over the past decades indicating that there is a strong association between childhood maltreatment and heavy episodic drinking in adolescence, but there is a paucity of empirically based knowledge about the processes linking the association. The aim of this paper is to examine mechanisms that might account for the association between childhood maltreatment and heavy episodic drinking in adolescence. Using a nationally representative sample of adolescents (ages ranging 12-21; N = 6,337), this study examined the role of individual self-regulatory processes in the associations, controlling for age, gender, race/ethnicity, peer substance use, parental alcoholism, and parent-child conflict. Factor analyses were used to test the measurement structure of self-regulatory processes. Findings confirmed the association between childhood maltreatment and heavy episodic drinking in adolescence. Structural modeling analyses indicated indirect effects for childhood maltreatment primarily through poor self-regulatory processes and peer substance use. Implications for future research are discussed.

Alcohol Consumption in Movies and Adolescent Binge Drinking in 6 European Countries

Alcohol Consumption in Movies and Adolescent Binge Drinking in 6 European Countries

High-Risk Driving Behaviors among Adolescent Binge Drinkers

Background: Binge drinking is common among adolescents. Alcohol use, particularly binge drinking, has been associated with neurocognitive deficits and increased risk-taking behaviors, which may contribute to negative driving outcomes among adolescents even while sober. Objectives: To examine potential differences in self-reported risky driving behaviors between adolescent binge drinkers and a matched sample of controls on measures of (1) compliance with graduated licensing laws, (2) high-risk driving behaviors, and (3) driving outcomes (i.e., crashes, traffic tickets). Methods: This study examined driving behaviors and outcomes in adolescent recent binge drinkers (n = 21) and demographically and driving history matched controls (n = 17) between the ages of 16–18 years. Results: Binge drinkers more frequently violated graduated licensing laws (e.g., driving late at night) and engaged in more “high-risk” driving behaviors, such as speeding and using a cell phone while driving. Binge drinkers had more traffic tickets, crashes, and “near crashes” than the control group. Speeding was the behavior most associated with crashes within the binge drinkers. Conclusion: In this study, binge-drinking teens consistently engage in more dangerous driving behaviors and experience more frequent crashes and traffic tickets. They are also less compliant with preventative restrictions placed on youth while they are learning critical safe driving skills. Scientific Significance: These findings highlight a need to examine the contribution of underlying traits (such as sensation seeking) and binge-related cognitive changes to these high-risk driving behaviors, which may assist researchers in establishing alternative prevention and policy efforts targeting this population.

Adolescent Binge Drinking Leads to Changes in Alcohol Drinking, Anxiety, and Amygdalar Corticotropin Releasing Factor Cells in Adulthood in Male Rats

Heavy episodic drinking early in adolescence is associated with increased risk of addiction and other stress-related disorders later in life. This suggests that adolescent alcohol abuse is an early marker of innate vulnerability and/or binge exposure impacts the developing brain to increase vulnerability to these disorders in adulthood. Animal models are ideal for clarifying the relationship between adolescent and adult alcohol abuse, but we show that methods of involuntary alcohol exposure are not effective. We describe an operant model that uses multiple bouts of intermittent access to sweetened alcohol to elicit voluntary binge alcohol drinking early in adolescence (∼postnatal days 28–42) in genetically heterogeneous male Wistar rats. We next examined the effects of adolescent binge drinking on alcohol drinking and anxiety-like behavior in dependent and non-dependent adult rats, and counted corticotropin-releasing factor (CRF) cell in the lateral portion of the central amygdala (CeA), a region that contributes to regulation of anxiety- and alcohol-related behaviors. Adolescent binge drinking did not alter alcohol drinking under baseline drinking conditions in adulthood. However, alcohol-dependent and non-dependent adult rats with a history of adolescent alcohol binge drinking did exhibit increased alcohol drinking when access to alcohol was intermittent. Adult rats that binged alcohol during adolescence exhibited increased exploration on the open arms of the elevated plus maze (possibly indicating either decreased anxiety or increased impulsivity), an effect that was reversed by a history of alcohol dependence during adulthood. Finally, CRF cell counts were reduced in the lateral CeA of rats with adolescent alcohol binge history, suggesting semi-permanent changes in the limbic stress peptide system with this treatment. These data suggest that voluntary binge drinking during early adolescence produces long-lasting neural and behavioral effects with implications for anxiety and alcohol use disorders.