Origin of the comorbidity of anxiety disorders and alcohol dependence: findings of a general population study

Pre- and postsynaptic signatures in the prelimbic cortex associated with "alcohol use disorder" in the rat

The transition to alcohol use disorder (AUD) involves persistent neuroadaptations in executive control functions primarily regulated by the medial prefrontal cortex. However, the neurophysiological correlates to behavioral manifestations of AUD are not fully defined. The association between cortical neuroadaptations and behavioral manifestations of addiction was studied using a multi-symptomatic operant model based on the DSM-5 diagnostic criteria for AUD. This model aimed to characterize an AUD-vulnerable and AUD-resistant subpopulation of outbred male Wistar rats and was combined with electrophysiological measurements in the prelimbic cortex (PL). Mirroring clinical observations, rats exhibited individual variability in their vulnerability to develop AUD-like behavior, including motivation to seek for alcohol (crit 1), increased effort to obtain the substance (crit 2), and continued drinking despite negative consequences (crit 3). Only a small subset of rats met all the aforementioned AUD criteria (3 crit, AUD-vulnerable), while a larger fraction was considered AUD-resilient (0 crit). The development of AUD-like behavior was characterized by disruptions in glutamatergic synaptic activity, involving decreased frequency of spontaneous excitatory postsynaptic currents (sEPSCs) and heightened intrinsic excitability in layers 2/3 PL pyramidal neurons. These alterations were concomitant with a significant impairment in the ability of mGlu2/3 receptors to negatively regulate glutamate release in the PL but not in downstream regions like the basolateral amygdala or nucleus accumbens core. In conclusion alterations in PL synaptic activity were strongly associated with individual addiction scores, indicating their role as potential markers of the behavioral manifestations linked to AUD psychopathology.

AUD in perspective

Alcohol is a major cause of pre-mature death and individual suffering worldwide, and the importance of diagnosing and treating AUD cannot be overstated. Given the global burden and the high attributable factor of alcohol in a vast number of diseases, the need for additional interventions and the development of new medicines is considered a priority by the World Health Organization (WHO). As of today, AUD is severely under-treated with a treatment gap nearing 90%, strikingly higher than that for other psychiatric disorders. Patients often seek treatment late in the progress of the disease and even among those who seek treatment only a minority receive medication, mirroring the still-prevailing stigma of the disease, and a lack of access to effective treatments, as well as a reluctance to total abstinence. To increase adherence, treatment goals should focus not only on maintaining abstinence, but also on harm reduction and psychosocial functioning. A personalised approach to AUD treatment, with a holistic view, and tailored therapy has the potential to improve AUD treatment outcomes by targeting the heterogeneity in genetics and pathophysiology, as well as reason for, and reaction to drinking. Also, the psychiatric co-morbidity rates are high in AUD and dual diagnosis can worsen symptoms and influence treatment response and should be considered in the treatment strategies.

The bidirectional relationship between anxiety disorders and alcohol use disorders in adults: Findings from a longitudinal population-based study

BACKGROUND

Anxiety disorders (AD) and alcohol use disorder (AUD) frequently co-occur, but the temporal order of the association is unclear. We have determined the association between AD and the presence and first-onset of AUD, and vice versa.

METHODS

Data were used from n = 6.646 participants and four measurement waves (baseline, 3-, 6- and 9-years) of the Netherlands Mental Health Survey and Incidence Study 2 (NEMESIS-2), a cohort study of the Dutch general population aged 18-64 years. AD and AUD were assessed with the Composite International Diagnostic Interview 3.0. Multilevel logistic autoregressive models were controlled for previous-wave AD or AUD, sociodemographics (Model 1), smoking and clinical factors (Model 2).

RESULTS

People with AUD had a higher risk of present (OR = 1.65, 95 % CI 1.11-2.43; Model 2) and first-onset (OR = 2.03, 95 % CI 1.17-3.51; Model 2) AD in 3-years follow-up intervals than people without AUD. Vice versa, people with AD also had a higher sociodemographics-adjusted risk of present and first-onset AUD over 3-years follow-up intervals, but these associations attenuated into insignificance after adjustment for smoking and clinical variables. Limitations For statistical power reasons we were not able to analyze 9-year follow-up data or distinguish between AD and AUD types.

CONCLUSIONS

Our results indicate a bidirectional relationship between AD and AUD; especially those with severe AD (medication use, comorbid depression) are at risk of developing AUD. Health care professionals should focus on prevention of AD in AUD patients and prevention of AUD in patients with (more severe) AD. Further research should investigate the mechanisms underlying the observed associations.

MUNC13-1 heterozygosity does not alter voluntary ethanol consumption or sensitivity in mice

The role of the munc13-1 presynaptic protein in alcohol-related behaviors has been little-studied, despite being a known site of action for ethanol binding. Munc13-1 is an active zone protein that plays a vital role in vesicle maturation and the release of neurotransmitters in excitatory neurons. Ethanol binds munc13-1, which decreases its functionality. In Drosophila, loss of the homologous protein Dunc13 is associated with an increase in ethanol preference, and is associated with a resistance to sedation following ethanol exposure. The current study assessed the effects of munc13-1 heterozygosity on ethanol sensitivity and consumption in mice, as well as on learning and anxiety-like behaviors, which can influence alcohol intake. Wild-type and mutant mice underwent 6 cycles of drinking-in-the-dark (DID) as well as rotarod testing following ethanol injection, to probe for differences in ethanol consumption and sensitivity, respectively. We did not detect genotype-based differences in our measures of anxiety, spatial learning, ethanol consumption, or ethanol sensitivity. However, heterozygotes showed increased use of a spatial navigation strategy in a dual-solution water maze, as opposed to a stimulus-response strategy. To summarize, although reduction of Dunc13 in flies produces clear effects on ethanol consumption and sensitivity, heterozygosity for munc13-1 does not, potentially due to compensatory adaptation by other munc-13 isoforms.

Nalmefene in Alcohol Use Disorder Subjects with Psychiatric Comorbidity: A Naturalistic Study

INTRODUCTION

Nalmefene is the first drug to be approved for reducing alcohol consumption in alcohol use disorder (AUD) patients at high drinking risk. In real-world settings, there is a high prevalence of concurrent psychiatric disorders in AUD subjects, with associated increased morbidity and worse prognosis. This study evaluated the use of nalmefene in AUD patients with stabilized psychiatric comorbidity previously treated unsuccessfully for alcohol dependence, and assessed craving reduction and safety.

METHODS

Sixty-five AUD outpatients treated with as-needed 18 mg nalmefene for 24 weeks were included. Primary outcome measures were: changes in heavy drinking days (HDDs) and total alcohol consumption (TAC, g/day). Secondary outcome measures were: changes in drinking risk level and craving (obsessive-compulsive drinking scale and visual analogue scale for craving).

RESULTS

Forty-two AUD subjects (64.6%) had one or more stabilized psychiatric comorbidity. There was a significant reduction in HDDs, TAC and craving measures (p < 0.001), with no differences between subjects with and without psychiatric comorbidity. Nalmefene was safe and well tolerated in all patients.

CONCLUSION

As-needed nalmefene reduced drinking and craving in AUD subjects with and without psychiatric comorbidity. These findings suggest that nalmefene is a valid therapeutic option in real-world clinical settings, where comorbid conditions are common, and has the potential to engage AUD patients who may otherwise not have sought help.

FUNDING

Lundbeck Italia S.P.A.

The Age of Onset of Anxiety Disorders

OBJECTIVE

The objective was to estimate the age of onset (AOO) for all anxiety disorders and for specific subtypes. Gender differences in the AOO of anxiety disorders were examined, as were the influence of study characteristics on reported AOOs.

METHODS

Seven electronic databases were searched up to October 2014, with keywords representing anxiety disorder subtypes, AOO, and study design. The inclusion criteria were studies using a general population sample that provided data on the AOO for all anxiety disorders, or specific anxiety disorders, according to DSM-III-R, DSM-IV, or ICD-10 criteria.

RESULTS

There were 1028 titles examined, which yielded 24 studies meeting the inclusion criteria. Eight studies reported the AOO and gender. Meta-analysis found a mean AOO of all anxiety disorders of 21.3 years (95% CI 17.46 to 25.07). Separation anxiety disorder, specific phobia, and social phobia had their mean onset before the age of 15 years, whereas the AOO of agoraphobia, obsessive-compulsive disorder, posttraumatic stress disorder, panic disorder, and generalized anxiety disorder began, on average, between 21.1 and 34.9 years. Meta-analysis revealed no difference in the AOO between genders. A prospective study design and higher developmental level of the study country were associated with an earlier AOO.

CONCLUSIONS

Results from this meta-analysis indicate that anxiety disorder subtypes differ in the mean AOO, with onsets ranging from early adolescence to young adulthood. These findings suggest that prevention strategies of anxiety disorders should be directed towards factors associated with the development of anxiety disorder subtypes in the age groups with the greatest vulnerability for developing those disorders.

Onset of Alcohol Use Disorders and Comorbid Psychiatric Disorders in a Military Cohort: Are there Critical Periods for Prevention of Alcohol Use Disorders?

Alcohol use disorders (AUD) are commonly comorbid with anxiety and mood disorders; however, a strategy for AUD prevention remains unclear in the presence of three competing etiological models that each recommends different high-risk groups. Therefore, the investigation of the three hypotheses in a characteristically unique cohort is critical to identifying pervasive characteristics of AUD that can inform a universal prevention strategy. The current study evaluated the temporality and onset of comorbid AUD and psychiatric disorders in a representative sample of 528 Ohio Army National Guard soldiers using structured clinical interviews from 2009 to 2012. We examined temporality both statistically and graphically to identify patterns that could inform prevention. General estimating equations with dichotomous predictor variables were used to estimate odds ratios between comorbid psychiatric disorders and AUDs. An annualized rate of 13.5 % persons per year was diagnosed with any AUD between 2010 and 2012. About an equal proportion of participants with comorbid psychiatric disorders and AUD initiated the psychiatric disorder prior to the AUD and half initiated the psychiatric disorder after the AUD. Regardless of onset, however, the majority (80 %) AUD initiated during a short interval between the ages of 16 and 23. Focused primary prevention during this narrow age range (16-23 years) may have the greatest potential to reduce population mental health burden of AUD, irrespective of the sequencing of comorbid psychiatric disorder.

Prevalence of comorbid substance use, anxiety and mood disorders in epidemiological surveys, 1990-2014: A systematic review and meta-analysis

BACKGROUND

Comorbidity is highly prevalent between substance use disorders (SUDs), mood and anxiety disorders. We conducted a systematic review and meta-analysis to determine the strength of association between SUDs, mood and anxiety disorders in population-based epidemiological surveys.

METHODS

A comprehensive literature search of Medline, EMBASE, CINAHL, PsychINFO, Web of Science, and Scopus was conducted from 1990 to 2014. Sources were chosen on the basis that they contained original research in non-clinical populations conducted in randomly selected adults living within defined boundaries. Prevalence of comorbid SUDs, mood and anxiety disorders and odds ratios (ORs) were extracted.

RESULTS

There were 115 articles identified by electronic searches that were reviewed in full text which yielded 22 unique epidemiological surveys to extract lifetime and 12-month prevalence data for psychiatric illness in respondents with an SUD. Meta-analysis indicated the strongest associations were between illicit drug use disorder and major depression (pooled OR 3.80, 95% CI 3.02-4.78), followed by illicit drug use and any anxiety disorder (OR 2.91, 95% CI 2.58-3.28), alcohol use disorders and major depression (OR 2.42, 95% CI 2.22-2.64) and alcohol use disorders and any anxiety disorder (OR 2.11, 95% CI 2.03-2.19). ORs for dependence were higher than those for abuse irrespective to diagnoses based on lifetime or 12-month prevalence.

CONCLUSIONS

This review confirms the strong association between SUDs, mood and anxiety disorders. The issue has now been recognised worldwide as a factor that affects the profile, course, patterns, severity and outcomes of these disorders.

Differential involvement of anxiety and novelty preference levels on oral ethanol consumption in rats

RATIONALE

Drug addiction is defined as a recurring cycle of intoxication, abstinence and relapse. The behavioural trait of novelty seeking is frequently observed in alcohol abusers. Moreover, converging evidence indicates that anxious individuals are also predisposed to alcohol abuse.

OBJECTIVES

We have analyzed the respective implication of those two behavioural factors on vulnerability to ethanol intake on rats in situations designed to reflect drug intoxication and relapse phases in humans.

METHODS

In a general population of Wistar rats, animals were tested in both the light/dark box and the novelty preference tests. Ethanol consumption was measured in a two-bottle free-choice procedure across three successive procedures. Animals were first exposed to increasing concentrations of ethanol (2, 4, 6, 8, 10, 12 % for 8 days at each concentration). Then, the concentration of the solution was diminished from 12 to 6 %. Finally, all rats were re-exposed to 6 % ethanol after 12 days of ethanol deprivation.

RESULTS

Novelty preference predicted the amount of ethanol consumed across all phases. In contrast, anxiety was associated with a quicker recovery of ethanol consumption after the concentration drop and a greater increase in ethanol consumption after deprivation.

CONCLUSIONS

Novelty seeking and anxiety are both but differentially implicated in predisposition to ethanol abuse. Whereas novelty seeking is related to the amount of ethanol consumed, anxiety is associated to higher ethanol consumption when ethanol concentration is decreased or after ethanol deprivation.

Familial factors associated with development of alcohol and mental health comorbidity

BACKGROUND AND AIMS

Co-occurring mental health and alcohol problems appear to be associated with greater health burdens than either single disorder. This study compares familial and individual contributions to development of comorbid alcohol/mental problems and tests whether these differ from single disorders.

DESIGN

Women (n = 6703) were recruited during pregnancy to the longitudinal Mater-University of Queensland Study of Pregnancy (MUSP). Mother/offspring dyads were followed over 21 years.

SETTING

Mater-Misericordiae Public Hospital, Brisbane, Australia.

PARTICIPANTS

Primary offspring from the MUSP with full psychiatric information at 21 years and maternal information at age 14 (n = 1755).

MEASUREMENTS

Structured interviews at age 21 yielded a four-category outcome using mental health and alcohol modules of the Composite International Diagnostic Interview (no disorder, alcohol only, mental health only and comorbid alcohol/mental health). Multinomial logistic regression models were adjusted for gender, maternal mental health and substance use, family environment and adolescent behaviour.

FINDINGS

Maternal smoking [odds ratio (OR) = 1.56; 95% confidence interval (CI) = 1.09-2.22 versus no-disorder] and low mother-offspring warmth (OR = 3.19; 95% CI = 1.99-5.13) were associated with mental health/alcohol comorbidity in young adults, as were adolescent drinking (OR = 2.22; 95% CI = 1.25-3.96), smoking (OR = 2.24; 95% CI = 1.33-3.77) and attention/thought problems (OR = 2.04; 95% CI = 1.18-3.52). Some differences were seen from single disorders. In a subsample with paternal data, fathers' drinking problems (OR = 2.41; 95% CI = 1.10-5.29) were more associated strongly with offspring mental health/alcohol comorbidity than both single disorders (P < 0.05).

CONCLUSIONS

Maternal smoking and low mother-child warmth appear to be related to alcohol, mental health and comorbid disorders at age 21, possibly via constituent alcohol and mental health disorders. Adolescent drinking and attention/thought problems appear to be associated with comorbid disorders but not with individual alcohol and mental health disorders.

Functional alterations in the dorsal raphe nucleus following acute and chronic ethanol exposure

Alcoholism is a pervasive disorder perpetuated in part to relieve negative mood states like anxiety experienced during alcohol withdrawal. Emerging evidence demonstrates a role for the serotonin-rich dorsal raphe (DR) in anxiety following ethanol withdrawal. The current study examined the effects of chronic ethanol vapor exposure on the DR using slice electrophysiology in male DBA2/J mice. We found that chronic ethanol exposure resulted in deficits in social approach indicative of increased anxiety-like behavior at both 24 h and 7 days post-ethanol exposure. At 24 h post-ethanol exposure, we observed increased excitability and decreased spontaneous inhibitory transmission (inhibitory postsynaptic currents, IPSCs) in the DR. At 7 days post-ethanol exposure, we observed increased spontaneous and miniature excitatory transmission (excitatory postsynaptic currents, EPSCs). Because acute ethanol alters GABA transmission in other brain regions, we assessed the effects of ex vivo ethanol (50 mM) on miniature IPSCs (mIPSCs) in the DR 24-h post-ethanol exposure. Bath application of ethanol enhanced the amplitude of mIPSCs in cells from ethanol-naive and chronic intermittent ethanol-exposed (CIE) mice, but significantly enhanced the frequency of mIPSCs only in cells from CIE mice, suggesting that DR neurons are more sensitive to the inhibitory effects of acute ethanol following CIE. On the basis of these findings, we hypothesize that net excitation of DR neurons following chronic ethanol exposure contributes to enhanced anxiety during ethanol withdrawal, and that increased sensitivity of DR neurons to subsequent ethanol exposure may mediate acute ethanol's ability to relieve anxiety during ethanol withdrawal.

Clustering of health risk behaviours and the relationship with mental disorders

BACKGROUND

Health risk behaviours tend to co-occur and are found to be related to mental health symptoms. This is the first study to identify health behaviour clusters in relation to mental disorders.

METHODS

Data were used from the second wave of the Netherlands Mental Health Survey and Incidence Study (NEMESIS-2), a nationally representative sample of adults (n=5303). Latent class analysis was performed to identify clusters based on four health risk behaviours (smoking, heavy drinking, physical inactivity, and unhealthy diet). Concurrently, we examined the relationship between the identified clusters and a range of DSM-IV diagnoses, assessed with the Composite International Diagnostic Interview 3.0.

RESULTS

Four distinct health behaviour clusters were identified: most healthy (mainly non-smokers, moderate drinkers, active, healthy diet; class 1: 79.3%); smokers, moderate drinkers, inactive, unhealthy diet (class 2: 13.2%); smokers, heavy episodic drinkers, active, unhealthy diet (class 3: 3.8%); Smokers, frequent heavy drinkers, active, low fruit (class 4: 3.6%). Despite their different lifestyles, individuals in all three unhealthy clusters had double the risk of depression. Unhealthy behaviour clusters were strongly associated with drug dependence (classes 2 and 3), alcohol abuse and dependence (classes 3 and 4), and social phobia (class 4).

LIMITATIONS

Due to the cross-sectional design, no conclusions about the causality of the relationship between HRB clusters and mental disorders can be drawn from the current study.

CONCLUSIONS

Health behaviour clusters are strongly associated with mental disorders. This co-existence of behaviours and disorders emphasises the importance of an integrative approach in the prevention of mental illnesses.

Do young people with comorbid mental and alcohol disorders experience worse behavioural problems?

This article examines whether young individuals in the general population with comorbid alcohol use and mental health disorders experience worse internalizing and externalizing behaviour problems than those with single disorders. A large cohort of women at the Mater Misericordiae Hospital in Brisbane, Australia, was enroled during pregnancy in a longitudinal study. Mother/offspring dyads were followed over 21 years. At age 21, offspring behaviour problems were examined using the Young Adult Self Report, alcohol and mental health disorders with the Composite International Diagnostic Interview. Associations between comorbidity and behaviour problems were assessed using multinomial logistic regression, accounting for life-course factors. Twelve per cent of young adults had alcohol/mental health DSM-IV disorders with significant temporal overlap. A further 16% had alcohol disorders only and 23% mental health disorders only. The comorbid group scored significantly higher on total and externalizing behaviour problems but not internalizing behaviour problems. Stronger associations of aggression/delinquency with comorbidity were not fully accounted for by factors known to influence separate development of mental health and alcohol disorders. Young adults with comorbid alcohol/mental health disorders experience more, and more severe, behavioural problems than those with single disorder types, indicating an increased burden from comorbidity, with implications for treatment and public order.

Increased risk of alcohol dependency in a cohort of National Guard troops with PTSD: a longitudinal study

Studies show high rates of co-morbid post-traumatic stress disorder (PTSD) and alcohol use disorder (AUD) but there is no consensus on the causal direction of the relationship. Some theories suggest AUD develops as a coping mechanism to manage PTSD symptoms and others that AUD is a vulnerability factor for PTSD. A third hypothesis posits independent developmental pathways stemming from a shared etiology, such as the trauma exposure itself. We examined these hypotheses using longitudinal data on 922 National Guard soldiers, representing a subsample (56%) of a larger pre- and post-deployment cross-sectional study of New Jersey National Guard soldiers deployed to Iraq. Measures included the PTSD Checklist (PCL), DSM-IV-based measures of alcohol use/misuse from the National Household Survey of Drug Use and Health and other concurrent mental health, military and demographic measures. Results showed no effect of pre-deployment alcohol status on subsequent positive screens for new onset PTSD. However, in multivariate models, baseline PTSD symptoms significantly increased the risk of screening positive for new onset alcohol dependence (AD), which rose 5% with each unit increase in PCL score (AOR = 1.05; 95% CI = 1.02-1.07). Results also supported the shared etiology hypothesis, with the risk of a positive screen for AD increasing by 9% for every unit increase in combat exposure after controlling for baseline PTSD status (AOR = 1.09; 95% CI = 1.03-1.15) and, in a subsample with PCL scores <34, by 17% for each unit increase in exposure (AOR = 1.17; 95% CI = 1.05-1.31). These findings have implications for prevention, treatment and compensation policies governing co-morbidity in military veterans.

The role of negative emotionality and impulsivity in depressive/anxiety disorders and alcohol dependence

BACKGROUND

Much is still unclear about the role of personality in the structure of common psychiatric disorders such as depressive/anxiety disorders and alcohol dependence. This study will therefore examine whether various traits of negative emotionality and impulsivity showed shared or specific associations with these disorders. Method Cross-sectional data were used from the Netherlands Study of Depression and Anxiety (NESDA), including individuals with no DSM-IV psychiatric disorder (n = 460), depressive/anxiety disorder only (i.e. depressive and/or anxiety disorder; n = 1398), alcohol dependence only (n = 32) and co-morbid depressive/anxiety disorder plus alcohol dependence (n = 358). Aspects of negative emotionality were neuroticism, hopelessness, rumination, worry and anxiety sensitivity, whereas aspects of impulsivity included disinhibition, thrill/adventure seeking, experience seeking and boredom susceptibility.

RESULTS

Aspects of negative emotionality formed a homogeneous dimension, which was unrelated to the more heterogeneous construct of impulsivity. Although all aspects of negative emotionality were associated with alcohol dependence only, associations were much stronger for depressive/anxiety disorder only and co-morbid depressive/anxiety disorder with alcohol dependence. The results for impulsivity traits were less profound and more variable, with disinhibition and boredom susceptibility showing modest associations with both depressive/anxiety disorder and alcohol dependence, whereas low thrill/adventure seeking and high disinhibition were more strongly related with the first and the latter, respectively.

CONCLUSIONS

Our results suggest that depressive/anxiety disorder and alcohol dependence result from shared as well as specific aetiological pathways as they showed the same associations with all aspects of negative emotionality, disinhibition and boredom susceptibility as well as specific associations with thrill/adventure seeking and disinhibition.

Do co-morbid anxiety disorders predict drinking outcomes in women with alcohol use disorders?

AIMS

It is unclear whether co-morbid anxiety disorders predict worse drinking outcomes during attempts to change drinking behavior. Studies have yielded mixed results, and have rarely examined drinking outcomes based on a specific type of anxiety disorder. Women with alcohol use disorders (AUDs) are of particular interest as they are at risk for co-morbid anxiety [Kessler et al. (1997) Lifetime co-occurrence of DSM-III-R alcohol abuse and dependence with other psychiatric disorders in the national co-morbidity survey. Arch Gen Psychiat 54:313-21].

METHODS

Participants were 260 women with AUDs participating in an alcohol-treatment outcome studies. The Timeline Follow-Back was used to assess drinking frequency (percent days drinking) prior, within and 6 months post-treatment. The current study tested the hypothesis that having at least one lifetime anxiety disorder diagnosed at baseline using the Structured Clinical Interview for DSM Disorders would be associated with more drinking at all study time points. Exploratory analyses examined patterns of drinking outcomes by specific anxiety diagnoses.

RESULTS

Lifetime anxiety diagnosis was linked to poorer drinking outcomes post-treatment (β = 0.15, P = 0.020), despite less frequent drinking prior to treatment. Analyses by specific anxiety diagnosis indicated that generalized anxiety disorder predicted poorer drinking outcomes within treatment (β = 0.14, P = 0.018) and during follow-up (β = 0.16, P = 0.014).

CONCLUSION

Co-morbid anxiety problems complicate treatment for AUDs among women. Further, specific anxiety disorders should be evaluated as distinct constructs as evidenced by the differential outcomes related to generalized anxiety disorder. Implications for treatment development for women with AUDs are discussed.

Bidirectional interactions between acute psychosocial stress and acute intravenous alcohol in healthy men

BACKGROUND

The biological mechanisms by which acute stress increases alcohol consumption are unclear. One potential mechanism is that stress acts by altering the pharmacological and subjective effects of alcohol. Acute stress produces a cascade of physiological and psychological effects, each with a distinctive time course. In this study, we investigated whether different phases of response to an acute stress alter the subjective effects of intravenous alcohol, by administering the drug at 2 different times after the stress.

METHODS

Healthy men (n = 25) participated in 2 sessions: 1 with the Trier Social Stress Test and the other with a nonstressful control task, each followed by infusions of intravenous alcohol (targeting 40 mg% in 5 minutes) and placebo. One group of participants received alcohol within 1 minute of completing the tasks (Alc0, n = 11), followed by placebo 30 minutes later. In the other group (Alc30, n = 14), the order of alcohol and placebo infusions was reversed. Subjective effects (i.e., anxiety, stimulation, want more) and physiological measures (heart rate, blood pressure, salivary cortisol) were measured before and at repeated intervals after the tasks and infusions.

RESULTS

Stress did not change the subjective effects of alcohol in either group. However, when individual differences in alcohol responses were considered, stress differentially altered the stimulant-like and sedative effects of alcohol. Among individuals who exhibited predominantly stimulant responses to alcohol in the nonstressful condition, stress decreased the stimulant-like effects of alcohol and "wanting more." By contrast, among participants who did not report stimulation after alcohol in the control session, stress decreased the sedative effects and increased "want more." In addition, alcohol administered immediately after the Trier Social Stress Test dampened cortisol responses yet prolonged negative subjective responses to the stress.

CONCLUSIONS

These findings demonstrate that there are bidirectional relationships between alcohol and stress. Alcohol influences responses to stress, and stress changes reactions to alcohol, depending on an individual's pattern of response to alcohol. This study highlights the fact that stress-alcohol interactions vary among individual drinkers, suggesting that the effects of stress on motivation to drink alcohol may also differ between individuals.

Comorbidity and risk indicators for alcohol use disorders among persons with anxiety and/or depressive disorders: findings from the Netherlands Study of Depression and Anxiety (NESDA)

INTRODUCTION

This study examines comorbidity of alcohol abuse and alcohol dependence as well as its risk indicators among anxious and/or depressed persons, also considering temporal sequencing of disorders.

METHODS

Baseline data from the Netherlands Study of Depression and Anxiety (NESDA) were used, including 2329 persons with lifetime DSM-IV anxiety (social phobia, generalized anxiety disorder, panic disorder, and agoraphobia) and/or depressive (major depressive disorder and dysthymia) disorders and 652 controls. Lifetime diagnoses of DSM-IV alcohol abuse and dependence were established, as well as information about socio-demographic, vulnerability, addiction-related and anxiety/depression-related characteristics. Temporal sequencing of disorders was established retrospectively, using age of onset.

RESULTS

Of persons with combined anxiety/depression 20.3% showed alcohol dependence versus 5.5% of controls. Prevalence of alcohol abuse was similar across groups (± 12%). Independent risk indicators for alcohol dependence among anxious and/or depressed persons were male gender, vulnerability factors (family history of alcohol dependence, family history of anxiety/depression, openness to experience, low conscientiousness, being single, and childhood trauma), addiction-related factors (smoking and illicit drug use) and early anxiety/depression onset. Persons with secondary alcohol dependence were more neurotic, more often single and lonelier, while persons with primary alcohol dependence were more often male and more extravert.

DISCUSSION

Alcohol dependence, but not abuse, is more prevalent in anxious and/or depressed persons. Persons with comorbid alcohol dependence constitute a distinct subgroup of anxious and/or depressed persons, characterized by addiction-related habits and vulnerability. However, considerable variation in characteristics exists depending on temporal sequencing of disorders. This knowledge may improve identification and treatment of those anxious and/or depressed patients who are additionally suffering from alcohol dependence.

Assessment and treatment of anxiety disorders in children and adolescents

This article reviews the current screening and assessment tools for anxiety disorders in children and adolescents, as well as evidence-based treatment interventions for these disorders. The following anxiety disorders are discussed: separation anxiety disorder, generalized anxiety disorder, specific phobia, panic disorder, social anxiety disorder (social phobia), and selective mutism. There are several well-studied screening and assessment tools to identify childhood anxiety disorders early and differentiate the various anxiety disorders. Evaluations of baseline somatic symptoms, severity, and impairment ratings of the anxiety disorders, and collecting ratings from several sources is clinically helpful in assessment and treatment follow-up. Cognitive-behavioral therapy (CBT) has been extensively studied and has shown good efficacy in treatment of childhood anxiety disorders. A combination of CBT and medication may be required for moderate to severely impairing anxiety disorders and may improve functioning better than either intervention alone. Selective serotonin reuptake inhibitors are currently the only medications that have consistently shown efficacy in treatment of anxiety disorders in children and adolescents. Despite proven efficacy, the availability of CBT in the community is limited. Current research is focusing on early identification of anxiety disorders in community settings, increasing the availability of evidence-based interventions, and modification of interventions for specific populations.

Sub-clinical anxiety and the onset of alcohol use disorders: longitudinal associations from the Baltimore ECA follow-up, 1981-2004

The current study examines the longitudinal relationship between anxiety disorders in general, specific phobia in particular, and subsequent-onset alcohol use disorders in an adult population-based sample. In addition, the authors explore whether the hypothesized associations vary by gender. Approximately 23 years of data from the Baltimore Epidemiological Catchment Area Follow-up (N = 587) allow for the estimation of the development of incident alcohol use disorders in later life among those with anxiety disorders at the time of the baseline interview in 1981. Although baseline specific phobias were common, neither the number of fears nor any specific fear was statistically associated with the onset of alcohol use disorders. Rather, the findings suggested a modest association between adult sub-clinical specific phobia (without substantial distress or interference) and later-onset alcohol use disorders (odds ratio = 3.2). Moreover, the authors found that this association might be stronger for women than for men.

Comorbidity of generalized anxiety disorder and substance use disorders: results from the National Epidemiologic Survey on Alcohol and Related Conditions

OBJECTIVE

Prior research has consistently documented a strong association between generalized anxiety disorder (GAD) and substance use disorder (SUD). Comorbidity of GAD and SUD (GAD-SUD) represents clinical challenges, as the patients' symptoms are often more severe and are frequently prolonged, making their management more complex when compared with individuals with GAD only. The purpose of this study was to examine whether individuals with GAD-SUD differ meaningfully from individuals with GAD and no SUD comorbidity (GAD-NSUD) in terms of demographic characteristics, risk factors, psychiatric comorbidity, and clinical correlates.

METHOD

Data were derived from the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (N = 43,093). Diagnoses were made using the Alcohol Use Disorder and Associated Disabilities Interview Schedule-DSM-IV Version.

RESULTS

We found that the lifetime prevalence rate of GAD-SUD is about 2.04%, while that of GAD-NSUD is 2.10%. Individuals with GAD-SUD showed higher psychiatric comorbidity rates than those with GAD-NSUD. Treatment-seeking rates for GAD are equally low in individuals with GAD-SUD and GAD-NSUD. Both groups were as likely to receive pharmacologic treatment for anxiety.

CONCLUSIONS

The findings of our study indicate that individuals with GAD-SUD constitute half of the lifetime prevalence of GAD and that GAD-SUD is associated with high overall vulnerability for additional psychopathology, particularly in the externalizing spectrum; higher disability; and higher use of alcohol and drugs to relieve anxiety symptoms.

Predictors of ethanol consumption in adult Sprague-Dawley rats: relation to hypothalamic peptides that stimulate ethanol intake

To investigate mechanisms in outbred animals that increase the propensity to consume ethanol, it is important to identify and characterize these animals before or at early stages in their exposure to ethanol. In the present study, different measures were examined in adult Sprague-Dawley rats to determine whether they can predict long-term propensity to overconsume ethanol. Before consuming 9% ethanol with a two-bottle choice paradigm, rats were examined with the commonly used behavioral measures of novelty-induced locomotor activity and anxiety, as assessed during 15 min in an open-field activity chamber. Two additional measures, intake of a low 2% ethanol concentration or circulating triglyceride (TG) levels after a meal, were also examined with respect to their ability to predict chronic 9% ethanol consumption. The results revealed significant positive correlations across individual rats between the amount of 9% ethanol ultimately consumed and three of these different measures, with high scores for activity, 2% ethanol intake, and TGs identifying rats that consume 150% more ethanol than rats with low scores. Measurements of hypothalamic peptides that stimulate ethanol intake suggest that they contribute early to the greater ethanol consumption predicted by these high scores. Rats with high 2% ethanol intake or high TGs, two measures found to be closely related, had significantly elevated expression of enkephalin (ENK) and galanin (GAL) in the hypothalamic paraventricular nucleus (PVN) but no change in neuropeptide Y (NPY) in the arcuate nucleus (ARC). This is in contrast to rats with high activity scores, which in addition to elevated PVN ENK expression showed enhanced NPY in the ARC but no change in GAL. Elevated ENK is a common characteristic related to all three predictors of chronic ethanol intake, whereas the other peptides differentiate these predictors, with GAL enhanced with high 2% ethanol intake and TG measures but NPY related to activity.

Relationship of combat experiences to alcohol misuse among U.S. soldiers returning from the Iraq war

OBJECTIVE

Studies have shown a relationship between combat experiences and alcohol misuse in military personnel; it is not known if there are specific combat experiences that confer a greater risk. The current study examined the association of specific types of combat experiences with a positive screen for alcohol misuse.

METHODS

1120 U.S. soldiers who were members of brigade combat infantry teams were surveyed anonymously 3-4 months after returning from deployment to Iraq regarding their experiences in combat and their physical and mental health. Combat items were independently rated and placed into the following categories: (1) Fighting; (2) Killing; (3) Threat to oneself; (4) Death/injury of others; (5) Atrocities; and, (6) Positive experiences. Alcohol misuse was measured using a 2-item alcohol screen combined with alcohol-related behavioral items.

RESULTS

Of the soldiers sampled, 25% (N=275) screened positive for alcohol misuse 3-4 months post-deployment; 12% (N=125) screened positive and exhibited alcohol-related behavioral problems. Most combat exposure factors were significantly related to alcohol misuse individually. When factors were analyzed simultaneously, soldiers who had higher rates of exposure to the threat of death/injury were significantly more likely to screen positive for alcohol misuse; exposure to atrocities predicted misuse of alcohol with alcohol-related behavioral problems.

CONCLUSIONS

High exposure to threatening situations and atrocities was associated with a positive screen for alcohol misuse. Clinicians treating combat veterans should be aware of the potential association of alcohol misuse with specific types of experiences and closely follow those soldiers upon their return home.

Trait anxiety and ethanol: anxiolysis in high-anxiety mice and no relation to intake behavior in an addiction model

Anxiety has been proposed to play a role in the development of alcohol addiction, but the exact mechanisms by which this occurs remain unclear. The present study aimed to verify the relationship between basal anxiety levels, the anxiolytic-like effect of ethanol, and ethanol intake in mice exposed to an addiction model. In one experiment Swiss mice were characterized as high-anxiety (HA), medium-anxiety (MA), or non-anxiety (NA) in the elevated plus maze and then received saline or ethanol 2 g/kg acutely and chronically and were again exposed to the same test. NA mice decreased while MA mice maintained anxiety indices over the test days, regardless of treatment. HA ethanol-treated mice showed an anxiolytic-like effect, both acutely and chronically, while the saline-treated ones maintained their basal anxiety levels. In another experiment HA and MA mice were exposed to an addiction model based on a 3-bottle free-choice paradigm (ethanol 5% and 10%, and water) consisting of four phases: acquisition (10 weeks), withdrawal (W, 2 weeks), reexposure (2 weeks), and quinine-adulteration (2 weeks). HA and MA control mice had access only to water. Mice were characterized as addicted, heavy-drinker and light-drinker [Fachin-Scheit DJ, Ribeiro AF, Pigatto G, Goeldner FO, Boerngen-Lacerda R. Development of a mouse model of ethanol addiction: naltrexone efficacy in reducing consumption but not craving. J Neural Transm 2006;113:1305-21.]. No difference was observed between HA and MA mice in their preference for and intake of ethanol. No correlation was observed between ethanol intake, during any phase, and anxiety indices measured in the basal tests and during the W phase. The differences in anxiety indices between HA and MA groups persisted in the test performed during ethanol withdrawal, suggesting a "trait" anxiety profile. The data suggest that despite the fact that high anxiety trait levels are important for the anxiolytic-like effects of ethanol, they are not a determining factor for high ethanol intake, at least not under these experimental conditions.

Interpersonal factors in understanding and treating posttraumatic stress disorder

Exposure to reminders of trauma underlies the theory and practice of most treatments for post-traumatic stress disorder (PTSD), yet exposure may not be the sole important treatment mechanism. Interpersonal features of PTSD influence its onset, chronicity, and possibly its treatment. The authors review interpersonal factors in PTSD, including the critical but underrecognized role of social support as both protective posttrauma and as a mechanism of recovery. They discuss interpersonal psychotherapy (IPT) as an alternative treatment for PTSD and present encouraging findings from two initial studies. Highlighting the potential importance of attachment and interpersonal relationships, the authors propose a mechanism to explain why improving relationships may ameliorate PTSD symptoms.

Stress, alcohol and drug interaction: an update of human research

A challenging question that continues unanswered in the field of addiction is why some individuals are more vulnerable to substance use disorders than others. Numerous risk factors for alcohol and other drugs of abuse, including exposure to various forms of stress, have been identified in clinical studies. However, the neurobiological mechanisms that underlie this relationship remain unclear. Critical neurotransmitters, hormones and neurobiological sites have been recognized, which may provide the substrates that convey individual differences in vulnerability to addiction. With the advent of more sophisticated measures of brain function in humans, such as functional imaging technology, the mechanisms and neural pathways involved in the interactions between drugs of abuse, the mesocorticolimbic dopamine system and stress systems are beginning to be characterized. This review provides a neuroadaptive perspective regarding the role of the hormonal and brain stress systems in drug addiction with a focus on the changes that occur during the transition from occasional drug use to drug dependence. We also review factors that contribute to different levels of hormonal/brain stress activation, which has implications for understanding individual vulnerability to drug dependence. Ultimately, these efforts may improve our chances of designing treatment strategies that target addiction at the core of the disorder.

Neurobiology of addiction. An integrative review

Evidence that psychoactive substance use disorders, bulimia nervosa, pathological gambling, and sexual addiction share an underlying biopsychological process is summarized. Definitions are offered for addiction and addictive process, the latter being the proposed designation for the underlying biopsychological process that addictive disorders are hypothesized to share. The addictive process is introduced as an interaction of impairments in three functional systems: motivation-reward, affect regulation, and behavioral inhibition. An integrative review of the literature that addresses the neurobiology of addiction is then presented, organized according to the three functional systems that constitute the addictive process. The review is directed toward identifying candidate neurochemical substrates for the impairments in motivation-reward, affect regulation, and behavioral inhibition that could contribute to an addictive process.