Onset and course of alcoholism over 25 years in middle class men

Disrupted diurnal oscillations of the gut microbiota in patients with alcohol dependence

Background

Patients with alcohol dependence (AD) can exhibit gut dysbacteria. Dysbacteria may co-occur with disruptions of circadian rhythmicity of the gut flora, which can aggravate AD. Herein, this study aimed to investigate diurnal oscillations of the gut microbiota in AD patients.

Methods

Thirty-two patients with AD, based on the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, and 20 healthy subjects were enrolled in this study. Demographic and clinical data were collected by self-report questionnaires. Fecal samples at 7:00 AM, 11:00 AM, 3:00 PM, and 7:00 PM were collected from each subject. 16S rDNA sequencing was conducted. Wilcoxon and Kruskal-Wallis tests were performed to characterize alterations and oscillations of the gut microbiota.

Results

We found that β-diversity of the gut microbiota in AD patients oscillated diurnally compared with healthy subjects (p = 0.01). Additionally, 0.66% of operational taxonomic units oscillated diurnally in AD patients versus 1.68% in healthy subjects. At different taxonomic levels, bacterial abundance oscillated diurnally in both groups, such as Pseudomonas and Prevotella pallens (all p < 0.05). β-diversity of the gut microbiota in AD patients with high daily alcohol consumption, high-level cravings, short AD durations, and mild withdrawal symptoms oscillated diurnally compared with other AD patients (all p < 0.05).

Conclusion

The gut microbiota in AD patients exhibits disruptions of diurnal oscillation, which may provide novel insights into mechanisms of AD and the development of therapeutic strategies.

Genome-wide association mapping of ethanol sensitivity in the Diversity Outbred mouse population

BACKGROUND

A strong predictor for the development of alcohol use disorder (AUD) is altered sensitivity to the intoxicating effects of alcohol. Individual differences in the initial sensitivity to alcohol are controlled in part by genetic factors. Mice offer a powerful tool to elucidate the genetic basis of behavioral and physiological traits relevant to AUD, but conventional experimental crosses have only been able to identify large chromosomal regions rather than specific genes. Genetically diverse, highly recombinant mouse populations make it possible to observe a wider range of phenotypic variation, offer greater mapping precision, and thus increase the potential for efficient gene identification.

METHODS

We have taken advantage of the Diversity Outbred (DO) mouse population to identify and precisely map quantitative trait loci (QTL) associated with ethanol sensitivity. We phenotyped 798 male J:DO mice for three measures of ethanol sensitivity: ataxia, hypothermia, and loss of the righting response. We used high-density MegaMUGA and GigaMUGA to obtain genotypes ranging from 77,808 to 143,259 SNPs. We also performed RNA sequencing in striatum to map expression QTLs and identify gene expression-trait correlations. We then applied a systems genetic strategy to identify narrow QTLs and construct the network of correlations that exists between DNA sequence, gene expression values, and ethanol-related phenotypes to prioritize our list of positional candidate genes.

RESULTS

We observed large amounts of phenotypic variation with the DO population and identified suggestive and significant QTLs associated with ethanol sensitivity on chromosomes 1, 2, and 16. The implicated regions were narrow (4.5-6.9 Mb in size) and each QTL explained ~4-5% of the variance.

CONCLUSIONS

Our results can be used to identify alleles that contribute to AUD in humans, elucidate causative biological mechanisms, or assist in the development of novel therapeutic interventions.

Late-Onset Alcohol Abuse as a Presenting Symptom of Neurodegenerative Diseases

BACKGROUND

The association between lifetime alcohol abuse and a higher risk to develop dementia is well known. However, it is unknown whether older adults who begin abusing alcohol late in life have an underlying neurodegenerative disease.

OBJECTIVE

Identify the frequency of lifelong alcohol abuse (L-AA), late-onset alcohol abuse (LO-AA), and alcohol abuse as a first symptom of dementia (AA-FS) in patients with neurodegenerative diseases.

METHODS

Cross-sectional retrospective study of patients evaluated at an academic referral center with a clinical diagnosis of behavioral variant frontotemporal dementia (bvFTD), Alzheimer-type dementia (AD), and semantic variant primary progressive aphasia (svPPA) (n = 1,518). The presence of alcohol abuse was screened with the National Alzheimer's Coordinating Center questionnaire. L-AA was defined as onset < 40 years, LO-AA as onset ≥40 years, and AA-FS was defined when the abuse started within the first three years from symptom onset.

RESULTS

The frequency of LO-AA was 2.2% (n = 33/1,518). LO-AA was significantly more frequent in patients with bvFTD than AD (7.5%, n = 13/173 versus 1.3%, n = 16/1,254, CI:1.0;11.4%), but not svPPA (4.4%, n = 4/91, CI: -4.4;10.7%). Similarly, AA-FS was more frequent in bvFTD patients than AD (5.7%, n = 10/173 versus 0.7%, n = 9/1,254, CI:0.5%;9.5%), but not svPPA (2.2%, n = 2/91, CI:-2.4;9.1%).

CONCLUSION

LO-AA can be a presenting symptom of dementia, especially bvFTD. Alcohol abuse onset later in life should prompt a clinical investigation into the possibility of an underlying neurodegenerative process because delay in diagnosis and treatment may increase patient and caregiver burden. The results need to be interpreted with caution due to the limitations of the study.

Maintaining recovery from alcohol use disorder during the COVID-19 pandemic: The importance of recovery capital

BACKGROUND

The potential impact of the COVID-19 pandemic on recovery from alcohol use disorder (AUD) has received scant attention to date. In response, we investigated the stability of recovery and identified correlates of relapse, with particular interest in differences between women and men.

METHODS

Data were obtained in a national survey of adults with resolved alcohol use disorder who were not drinking heavily (n = 1492). We calculated summary statistics and modeled odds of mild relapse (i.e., resolved at the time of data collection), overall and stratified by gender.

RESULTS

Equivalent large majorities of women and men reported that the COVID-19 pandemic had not affected their recovery at all (88.9% and 88.8%, respectively). Mild relapse events were infrequent, with only 45 participants (3.1%) reporting a resumption of drinking after being abstinent and 35 participants (2.7%) reporting an increase from previously moderated drinking, with no differences in prevalence between men and women. Recovery capital showed consistent and comparable protective effects for both women and men (adjusted odds ratio [aOR] 0.90; 95% confidence interval [95% CI] 0.84, 0.97; and aOR 0.93; 95% CI 0.88, 0.98, respectively). We did not find any effect of pandemic-related stressors; however, there were a number of distinct correlates of mild relapse for women and men.

CONCLUSIONS

Recovery capital showed a consistently protective effect and may serve as a highly suitable intervention target as it is modifiable. Given gender differences, assessments of other key factors and tailored interventions targeting women and men may be necessary to ensure stable recovery.

Alcohol and Brain Development in Adolescents and Young Adults: A Systematic Review of the Literature and Advisory Report of the Health Council of the Netherlands

Young people, whose brains are still developing, might entail a greater vulnerability to the effects of alcohol consumption on brain function and development. A committee of experts of the Health Council of the Netherlands evaluated the state of scientific knowledge regarding the question whether alcohol negatively influences brain development in young people. A systematic literature search for prospective studies was performed in PubMed and PsychINFO, for longitudinal studies of adolescents or young adults ranging between 12 and 24 y of age at baseline, investigating the relation between alcohol use and outcome measures of brain structure and activity, cognitive functioning, educational achievement, or alcohol use disorder (AUD), with measures at baseline and follow-up of the outcome of interest. Data were extracted from original articles and study quality was assessed using the Newcastle-Ottawa Scale. A total of 77 studies were included, 31 of which were of sufficient quality in relation to the study objectives. There were indications that the gray matter of the brain develops abnormally in young people who drink alcohol. In addition, the more often young people drink or the younger they start, the higher the risk of developing AUD later in life. The evidence on white matter volume or quality, brain activity, cognitive function, and educational achievement is still limited or unclear. The committee found indications that alcohol consumption can have a negative effect on brain development in adolescents and young adults and entails a risk of later AUD. The committee therefore considers it a wise choice for adolescents and young adults not to drink alcohol.

A meta-regression of methodological features that predict the effects of medications on the subjective response to alcohol

BACKGROUND

Alcohol administration paradigms have been used for early efficacy testing of novel compounds for alcohol use disorder (AUD). There has been an ongoing debate about sample characteristics and methodological features that affect the likelihood of detecting an early efficacy signal for AUD medications. We conducted a meta-regression to test whether the drinking level of the study sample and the peak breath alcohol concentration (BrAC) in the alcohol administration study predict the efficacy of AUD pharmacotherapies on the subjective responses to alcohol.

METHODS

We computed the effects of 21 medications on alcohol-induced stimulation, sedation, negative mood, and craving during alcohol administration in 49 studies.

RESULTS

Meta-regression analyses indicated a significant and positive effect of pre-study drinks per month on alcohol-induced stimulation (β = 0.142, p < 0.0001), such that as drinking increases, the benefit of medication over placebo decreases. There was an effect of drinks per month on negative mood (β = -0.164, p = 0.0248), such that at higher levels of drinks per month, the effects of medications on negative mood are stronger. For sedation, there was an effect of peak BrAC (β = 0.119, p = 0.0002), such that at low levels of peak BrAC, the effects of medication on sedation were null. For craving, there was a peak BrAC × drinks per month interaction such that at low levels of BrAC, a heavier drinking sample is required to detect the effects of medication on craving. Sensitivity analyses comparing naltrexone studies and non-naltrexone studies suggested that naltrexone was less sensitive to drinks per month across subjective response domains.

CONCLUSIONS

These analyses show that design features are critical in studies that test the effects of medications on the subjective responses to alcohol. By specifying the significance and directionality of these effects, as well as the specific points in BrAC or drinks per month at which medication effects are detectable, the study offers recommendations for design features of alcohol administration studies that aim to inform AUD medication development.

Desformylflustrabromine (dFBr), a positive allosteric modulator of the α4β2 nicotinic receptor modulates the hypnotic response to ethanol

BACKGROUND

Binge drinking can increase an individual's risk of developing alcohol use disorder (AUD). Ethanol targets multiple neurotransmitter systems; however, not much is known about its effects on the cholinergic system. Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels, the heteromeric α₄β₂ nAChR being a commonly expressed subtype. Desformylflustrabromine (dFBr), a positive allosteric modulator (PAM), increases the efficacy of α₄β₂ nAChR in vitro and has previously been shown to have translational potential. In this study, we investigated whether dFBr modulates the hypnotic response to ethanol.

METHODS

Ethanol-induced loss of righting reflex (LORR) duration was measured in the presence and absence of dFBr. The β₂ nAChR selective antagonist dihydro-β-erythroidine (DHβE) was used to study the involvement of the β₂ subunit. Additionally, we used a crosslinking-based western blot assay to estimate changes in total versus intracellular α₄ nAChR protein in thalamic tissue of rats treated with vehicle, dFBr, ethanol, or ethanol and dFBr. Lastly, using Xenopus oocyte two-electrode voltage clamp (TEVC) studies, we determined the effects of ethanol and dFBr on α₄β₂ nAChR.

RESULTS

Pretreatment with 6 mg/kg dFBr reduced ethanol-induced LORR duration as compared to rats treated with ethanol alone. LORR studies with DHβE suggest that dFBr reduced ethanol-induced LORR duration via the β₂ nAChR subunit. Crosslinking-based western analyses revealed that ethanol caused early increases in total and presumably surface thalamic α₄ nAChR subunit protein levels. This ethanol-induced α₄ nAChR upregulation was significantly reduced in rats pretreated with 6 mg/kg dFBr. In TEVC studies, ethanol potentiated ACh-induced currents in α₄β₂ nAChR, while it slightly reduced dFBr potentiation of maximal ACh currents.

CONCLUSIONS

Our results suggest that thalamic nAChRs containing the α₄ subunit are rapidly upregulated by a single intoxicating dose of ethanol. Furthermore, dFBr, an α₄β₂ nAChR-selective PAM, significantly attenuates the hypnotic response to ethanol via actions on β₂ nAChR. Overall, these results indicate that dFBr represents an option to reverse ethanol intoxication.

Ethanol-Related Behaviors in Mouse Lines Selectively Bred for Drinking to Intoxication

Alcohol use disorder (AUD) is a devastating psychiatric disorder that has significant wide-reaching effects on individuals and society. Selectively bred mouse lines are an effective means of exploring the genetic and neuronal mechanisms underlying AUD and such studies are translationally important for identifying treatment options. Here, we report on behavioral characterization of two replicate lines of mice that drink to intoxication, the High Drinking in the Dark (HDID)-1 and -2 mice, which have been selectively bred (20+ generations) for the primary phenotype of reaching high blood alcohol levels (BALs) during the drinking in the dark (DID) task, a binge-like drinking assay. Along with their genetically heterogenous progenitor line, Hs/Npt, we tested these mice on: DID and drinking in the light (DIL); temporal drinking patterns; ethanol sensitivity, through loss of righting reflex (LORR); and operant self-administration, including fixed ratio (FR1), fixed ratio 3:1 (FR3), extinction/reinstatement, and progressive ratio (PR). All mice consumed more ethanol during the dark than the light and both HDID lines consumed more ethanol than Hs/Npt during DIL and DID. In the dark, we found that the HDID lines achieved high blood alcohol levels early into a drinking session, suggesting that they exhibit front loading like drinking behavior in the absence of the chronicity usually required for such behavior. Surprisingly, HDID-1 (female and male) and HDID-2 (male) mice were more sensitive to the intoxicating effects of ethanol during the dark (as determined by LORR), while Hs/Npt (female and male) and HDID-2 (female) mice appeared less sensitive. We observed lower HDID-1 ethanol intake compared to either HDID-2 or Hs/Npt during operant ethanol self-administration. There were no genotype differences for either progressive ratio responding, or cue-induced ethanol reinstatement, though the latter is complicated by a lack of extinguished responding behavior. Taken together, these findings suggest that genes affecting one AUD-related behavior do not necessarily affect other AUD-related behaviors. Moreover, these findings highlight that alcohol-related behaviors can also differ between lines selectively bred for the same phenotype, and even between sexes within those same line.

Alcohol Sensitivity as an Endophenotype of Alcohol Use Disorder: Exploring Its Translational Utility between Rodents and Humans

Alcohol use disorder (AUD) is a complex, chronic, relapsing disorder with multiple interacting genetic and environmental influences. Numerous studies have verified the influence of genetics on AUD, yet the underlying biological pathways remain unknown. One strategy to interrogate complex diseases is the use of endophenotypes, which deconstruct current diagnostic categories into component traits that may be more amenable to genetic research. In this review, we explore how an endophenotype such as sensitivity to alcohol can be used in conjunction with rodent models to provide mechanistic insights into AUD. We evaluate three alcohol sensitivity endophenotypes (stimulation, intoxication, and aversion) for their translatability across human and rodent research by examining the underlying neurobiology and its relationship to consumption and AUD. We show examples in which results gleaned from rodents are successfully integrated with information from human studies to gain insight in the genetic underpinnings of AUD and AUD-related endophenotypes. Finally, we identify areas for future translational research that could greatly expand our knowledge of the biological and molecular aspects of the transition to AUD with the broad hope of finding better ways to treat this devastating disorder.

The personality profile of chronic alcohol dependent patients with comorbid gambling disorder symptoms

BACKGROUND AND AIMS

The importance of personality characteristics in the diagnosis and treatment of gambling disorder (GD) and alcohol use disorder (AUD) is often highlighted in scientific literature. This study aimed to test predictions about the associations of temperament and character in chronic AUD patients with comorbid GD symptoms and without them.

METHODS

Chronic AUD patients enrolled from an inpatient clinic were divided in two groups based on cluster analysis, AUD patients with (AUD + GD group: n = 30) and without (AUD group: n = 68) GD symptoms. Severity of GD symptoms and personality dimensions (Cloninger's Temperament and Character Inventory Revised, TCI-R) were assessed. Associations of tested variables were analysed with analysis of covariance, one-sample and independent sample t-tests.

RESULTS

GD symptoms proved to be a clustering factor in terms of personality, where AUD + GD group expressed a more maladaptive personality profile. Compared to Hungarian normative TCI-R scores, both patient groups showed elevated levels of Harm Avoidance and Novelty Seeking with lower scores of Self-directedness, while the AUD + GD group scored lower on Persistence and Cooperation as well. The AUD + GD group reported significantly higher levels of Harm Avoidance, with lower scores of Reward Dependence compared to the AUD group.

DISCUSSION

Comorbid GD symptom severity is an important factor in chronic AUD, where AUD patients with comorbid GD symptoms exhibited a more maladaptive personality constellation than singular AUD patients. These emphasize the need of special attention for comorbid GD symptoms in AUD, since treatment recommendations and prognosis for them may also differ.

Alcohol use disorder relapse factors: A systematic review

A relapsing-remitting course is very common in patients with an Alcohol Use Disorder (AUD). Understanding the determinants associated with alcohol resumption remains a formidable task. This paper examines relapse determinants based on a systematic review of recent alcohol literature (2000-2019). Relevant databases were consulted for articles that contained information about specific relapse determinants and reported statistical significance of each relapse determinant in predicting relapse. Relapse was broadly defined based on the characterization in the included articles. From the initial identified 4613 papers, a total of 321 articles were included. Results encompass multiple relapse determinants, which were ordered according to biopsychosocial and spiritual categories, and presented, using a descriptive methodology. Psychiatric co-morbidity, AUD severity, craving, use of other substances, health and social factors were consistently significantly associated with AUD relapse. Conversely, supportive social network factors, self efficacy, and factors related to purpose and meaning in life, were protective against AUD relapse. Despite heterogeneity in different methods, measures, and sample characteristics, these findings may contribute to a better therapeutic understanding in which specific factors are associated with relapse and those that prevent relapse. Such factors may have a role in a personalized medicine framework to improve patient outcomes.

Remission from Alcohol Use Disorder among Males in the Lundby Cohort during 1947-1997

Background

Alcohol use disorders are a major health problem, often with a chronic course. Studies on remission from alcohol use disorders are sparse.

Objective

The aim of this study was to analyse the rate of remission from AUD and the possible influence of other mental disorders and sociodemographic factors on the remission in the Lundby Cohort.

Method

Remission from AUD was studied for 312 male subjects in the Lundby Cohort, which was followed for 50 years. Cox regression analyses were used to study the possible influence of sociodemographic variables and other mental disorders on AUD remission.

Results

In all, 64/312 (21%) subjects achieved remission during the study period. The presence of a severe mental disorder, such as delirium tremens and organic disorders, was related to remission. Blue-collar workers had higher rates of remission than white-collar workers. There was indication that treatment improved the prognosis.

Conclusions

The overall remission rate was low, but treatment may improve the prognosis. Severe mental disorders, such as delirium tremens and organic disorders as well as being blue-collar rather than white-collar worker, were related to remission.

Dynamic changes in gene expression and alternative splicing mediate the response to acute alcohol exposure in Drosophila melanogaster

Environmental changes typically cause rapid gene expression responses in the exposed organisms, including changes in the representation of gene isoforms with different functions or properties. Identifying the genes that respond to environmental change, including in genotype-specific ways, is an important step in treating the undesirable physiological effects of stress, such as exposure to toxins or ethanol. Ethanol is a unique environmental stress in that chronic exposure results in permanent physiological changes and the development of alcohol use disorders. Drosophila is a classic model for deciphering the mechanisms of the response to alcohol exposure, as it meets the criteria for the development of alcohol use disorders, and has similar physiological underpinnings with vertebrates. Because many studies on the response to ethanol have relied on a priori candidate genes, broad surveys of gene expression and splicing are required and have been investigated here. Further, we expose Drosophila to ethanol in an environment that is genetically, socially, and ecologically relevant. Both expression and splicing differences, inasmuch as they can be decomposed, contribute to the response to ethanol in Drosophila melanogaster. However, we find that while D. melanogaster responds to ethanol, there is very little genetic variation in how it responds to ethanol. In addition, the response to alcohol over time is dynamic, suggesting that incorporating time into studies on the response to the environment is important.

Cloninger's Temperament Dimensions and Longitudinal Alcohol Use in Early Midlife: A Northern Finland Birth Cohort 1966 Study

BACKGROUND

Temperament is theorized to be an important factor contributing to the development of alcohol use disorder, but longitudinal studies on how temperament is related to alcohol use among general population in midlife are scarce. Our aims were to investigate potentially reciprocal associations between temperament and changes in alcohol use from age 31 to 46 using prospective birth cohort data.

METHOD

Within the Northern Finland Birth Cohort 1966, alcohol use and temperament were studied at ages 31 and 46. Participants (N = 5,274) were classified into moderate users, abstainers and heavy users based on their mean alcohol use (g/d). Additionally, participants were categorized as steady users, reducers, or increasers. Multinomial regression analyses were conducted with Cloninger's Temperament and Character Inventory (TCI) scores as factors influencing alcohol use using moderate and stable users as reference groups. Reciprocity of relations was assessed with cross-lagged structural equation modeling.

RESULTS

Temperament and alcohol use are rather stable in midlife. Novelty seeking (NS) predicted heavy use (OR = 1.4; CI: 1.3 to 1.6 for men, OR = 1.3; CI: 1.1 to 1.5 for women) and increasing use (OR = 1.2; CI: 1.1 to 1.4 for men, OR = 1.1; CI: 1.0 to 1.3 for women), whereas low NS predicted abstaining among women (OR = 0.7; CI: 0.6 to 0.8). High harm avoidance (HA) predicted abstaining (OR = 1.3; CI: 1.1 to 1.5) for men. Low persistence (P) among men predicted both abstaining (OR = 0.9; CI: 0.7 to 0.98) and heavy use (OR = 0.9; CI: 0.8 to 0.98). Among women, low reward dependence (RD) predicted heavy use (OR = 0.8; CI: 0.7 to 0.9). Among TCI scores, only NS predicted increasing use in the cross-lagged models.

CONCLUSIONS

Temperament has an impact on alcohol use in midlife. Of the TCI dimensions, only NS seems to predispose to increased alcohol use and problem use throughout life. Additionally, RD among women and P among men are significant factors from a life-course perspective. Our results did not support Cloninger's theory on type I alcoholism, as HA showed no relation to problematic alcohol use in midlife.

Drinking Status Between Ages 50 and 55 for Men From the San Diego Prospective Study Who Developed DSM-IV Alcohol Abuse or Dependence in Prior Follow-Ups

OBJECTIVE

Although alcohol use disorders (AUDs) are prevalent among older individuals, few studies have examined the course and predictors of AUDs from their onset into the person's 50s. This study describes the AUD course from ages 50 to 55 in participants who developed AUDs according to criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), during the San Diego Prospective Study (SDPS).

METHOD

Among the 397 university students in the SDPS who were followed about every 5 years from age 20 (before AUD onset), 165 developed AUDs, 156 of whom were interviewed at age 55. Age 50-55 outcomes were compared regarding age 20-50 characteristics. Variables that differed significantly across outcome groups were evaluated using binary logistic regression analyses predicting each outcome type.

RESULTS

Between ages 50 and 55, 16% had low-risk drinking, 36% had high-risk drinking, 38% met DSM-5 AUD criteria, and 10% were abstinent. Baseline predictors of outcome at ages 50-55 included earlier low levels of response to alcohol predicting DSM-5 AUDs and abstinence, higher drinking frequency predicting DSM-5 diagnoses and lower predicting low-risk drinking, higher participation in treatment and/or self-help groups predicting abstinence and lower predicting DSM-5 AUDs, later ages of AUD onset predicting high-risk drinking, and cannabis use disorders predicting abstinent outcomes.

CONCLUSIONS

Despite the high functioning of these men, few were abstinent or maintained low-risk drinking during the recent 5 years, and 38% met DSM-5 AUD criteria. The data may be helpful to both clinicians and researchers predicting the future course of AUDs in their older patients and research participants.

Residual Effects: Young Adult Diagnostic Drinking Predicts Late-Life Health Outcomes

OBJECTIVE

This study examined the residual effects of young adult diagnostic drinking on health outcomes four decades later in late life. Results were differentiated by drinking status during midlife.

METHOD

A subsample of Vietnam Era Twin Registry members, all of whom had a lifetime diagnosis of alcohol dependence, was grouped according to life span drinking patterns as assessed by the Lifetime Drinking History interview in 2001. Those drinking at diagnostic levels (endorsing three or more alcohol dependence symptoms) before age 30 were then grouped based on their midlife drinking status (i.e., drinking at diagnostic levels vs. at minimal [nonsymptomatic] levels throughout midlife). Linear (or logistic) regression models were used to examine the association between life span drinking patterns and health outcomes in late life (about age 64).

RESULTS

Those who drank at diagnostic levels in young adulthood and in midlife exhibited significant health liabilities on every late-life health measure; those who drank at diagnostic levels for 5 or more years in young adulthood but drank only at minimal levels or not at all in midlife still exhibited similar liabilities on most late-life health measures. Only those individuals who drank diagnostically for less than 5 years in young adulthood displayed normal levels of late-life health.

CONCLUSIONS

This study identified residual effects resulting from persistent young adult diagnostic drinking (5 or more years) that resulted in negative health outcomes in late life even after decades of remission. There is a distal but surprisingly strong association between persistent early life diagnostic drinking and late-life morbidity.

Craving and acute effects of alcohol in youths' daily lives: Associations with alcohol use disorder severity

Identifying factors associated with the progression from recreational to pathological drinking in youth holds high clinical and theoretical importance. The present study tested cross-sectional associations of alcohol use disorder (AUD) severity with putative mechanisms of AUD progression among youth ages 15-24 years, namely acute subjective effects of alcohol and craving. Male (n = 44) and female (n = 42) youth completed ecological momentary assessments when not drinking, just before drinking, and while drinking in the natural environment via handheld wireless devices. Youth were recruited from the community and were frequent and heavy drinkers, the majority (93%) with at least 1 AUD symptom (M = 3.4, SD = 2.4). Findings from youths' daily lives suggested that how youth feel while they drink depends, in part, on their severity of AUD pathology. In support of hypotheses, youths with more progressed drinking pathology (i.e., those with more symptoms of AUD) reported greater reductions in craving and tension while drinking, relative to nondrinking times. In partial support of hypotheses, males with greater AUD symptomatology reported marginally attenuated increases in stimulatory states while drinking; however, contrary to hypotheses, females with greater AUD symptomatology reported enhanced increases in stimulation while drinking. This research leveraged ecological momentary assessment methods to study subjective responses to alcohol and craving in youths' daily lives and to cross-sectionally test putative associations with AUD etiology. This work adds to literature supporting subjective responses to alcohol in the pathogenesis of alcoholism, specifically by highlighting their importance during the period in life when alcohol problems typically first emerge. (PsycINFO Database Record

Are Alcohol Trajectories a Useful Way of Identifying At-Risk Youth? A Multiwave Longitudinal-Epidemiologic Study

OBJECTIVE

Trajectory approaches are a popular way of identifying subgroups of children and adolescents at high risk for developing alcohol use problems. However, mounting evidence challenges the meaning and utility of these putatively discrete alcohol trajectories, which can be analytically derived even in the absence of real subgroups. This study tests the hypothesis that alcohol trajectories may not reflect discrete groups-that the development of alcohol use is continuous rather than categorical.

METHOD

A multiwave longitudinal-epidemiologic twin study was conducted using 3,762 twins (1,808 male and 1,954 female) aged 11 to 29 years from the Minnesota Center for Twin and Family Research (MCTFR). The main outcome measures included various assessments of substance use, psychopathology, personality, and cognitive ability.

RESULTS

Although multiple trajectories are derived from growth mixture modeling techniques, these trajectories are arrayed in a tiered spectrum of severity, from lower levels of use to higher levels of use. Trajectories show perfect rank-order stability throughout development, monotonic increases in heritability, and perfect rank-order correlations with established correlates of alcohol use, including other substance use behaviors, psychiatric disorders, personality traits, intelligence, and achievement.

CONCLUSION

Alcohol trajectories may represent continuous gradations rather than qualitatively distinct subgroups. If so, early detection and interventions for youth based on trajectory subtyping will be less useful than continuous liability assessments. Furthermore, a continuous account of development counters the notion that individuals are predestined to follow one of a few categorically distinct pathways and promotes the opposite idea-that development is mutable, and its continuous terrain can be traversed in many directions.

Treatment with the Self-Discovery Camp (SDiC) improves Internet gaming disorder

INTRODUCTION

Internet gaming disorder (IGD) is a novel behavioral addiction that influences the physical, mental, and social aspects of health due to excessive Internet gaming. One type of intensive treatment for IGD is the therapeutic residential camp (TRC), which comprises many types of therapies, including psychotherapy, psychoeducational therapy, and cognitive behavioral therapy. The TRC was developed in South Korea and has been administered to many patients with IGD; however, its efficacy in other countries remains unknown. We investigated the efficacy of the Self-Discovery Camp (SDiC), a Japanese version of a TRC, and the correlations between individual characteristics and outcome measures.

METHODS

We recruited 10 patients with IGD (all male, mean age=16.2years, diagnosed using the DSM-5) to spend 8 nights and 9days at the SDiC. We measured gaming time as well as self-efficacy (using the Stages of Change Readiness and Treatment Eagerness Scale, a measure of therapeutic motivation and problem recognition).

RESULTS

Total gaming time was significantly lower 3months after the SDiC. Problem recognition and self-efficacy towards positive change also improved. Furthermore, there was a correlation between age of onset and problem recognition score.

CONCLUSIONS

Our results demonstrate the effectiveness of the SDiC for IGD, especially regarding gaming time and self-efficacy. Additionally, age of onset may be a useful predictor of IGD prognosis. Further studies with larger sample sizes and control groups, and that target long-term outcomes, are needed to extend our understanding of SDiC efficacy.

Subjective alcohol responses in a cross-sectional, field-based study of adolescents and young adults: Effects of age, drinking level, and dependence/consequences

BACKGROUND

Adolescents are physically, cognitively, socially, and emotionally different than adults in ways that may partially explain why alcohol misuse typically develops during this period. Ample animal-science evidence and nascent ecological evidence points toward developmentally limited differences in sensitivity to alcohol's stimulatory and sedative effects. Field-based research methods were used to test for such age-related differences in a sample of adolescents through young adults. Potential moderating influences of estimated blood alcohol content (eBAC), as well as typical consumption and level of dependence/consequences were explored.

METHODS

Subjective alcohol responses were collected from 1,364 participants, aged 17 to 32 years, recruited outside of venues where drinking takes place in a small metropolitan bar district.

RESULTS

Self-reports of stimulatory response to alcohol were age-related, such that younger participants reported increased subjective stimulation at the time of data collection relative to older participants. Age-related differences in stimulatory responses were more pronounced at lower eBACs and among younger participants who typically drank more heavily. Stimulatory responses generally diminished among older than younger participants, although individuals with greater dependence/consequences consistently reported greater stimulation from drinking. Contrastingly, age, typical consumption, and dependence/consequences were not related to sedation in this sample.

CONCLUSIONS

This research provides cross-sectional evidence to support age-, consumption-, and dependence/consequences-related differences in stimulatory alcohol responses among adolescents and young adults assessed within a bar-area context. While cross-sectional, the results of this field-based study provide support for the theory that addiction liability is developmentally linked and associated, in part, with age-related differences in subjective alcohol responses.

Remission from substance use disorders: A systematic review and meta-analysis

OBJECTIVE

This paper presents a systematic review and meta-analysis of available evidence on remission rates for substance use disorders (SUDs), providing weighted mean estimates of SUD remission rates. The review also explores study-level characteristics that may explain variations in remission rates across studies.

METHODS

A comprehensive search strategy identified studies published between 2000 and 2015 with follow-up periods of at least three years or reported lifetime remission outcomes for potential inclusion in the review. Remission was defined as not meeting diagnostic criteria for abuse or dependence for a minimum period of six months, as of final follow-up. A single-group summary meta-analysis was performed. Pooled estimated annual remission rates (PEARRs) were calculated. Meta-regression techniques and subgroup analyses were used to explore the association between study remission rates and key selected variables.

RESULTS

Of 8855 studies identified, 21 met the eligibility criteria. The results suggested that 35.0% to 54.4% of individuals with SUDs achieved remission, and this occurred after a mean follow-up period of 17 years. The PEARRs projected few cases of SUD remission, between 6.8% and 9.1% in any given year. Studies that reported higher remission rates had longer follow-up periods, and lower sample retention rates.

CONCLUSIONS

Results support the contention that SUDs are more likely to be "chronic" or long term disorders than acute disorders for a substantial number of individuals. However, more longitudinal research is required. Treatment geared to chronicity, such as assertive community treatment and intensive case management, needs to be more readily available for SUD populations.

Acute subjective response to alcohol as a function of reward and punishment sensitivity

Individual differences in subjective response to alcohol play a crucial role in the development of heavy drinking and related problems. In light of this, a growing focus of research has been identifying factors that contribute to differences in response. The aim of the present study was to determine whether individual differences in the subjective experience of rewarding and aversive effects of alcohol are a specific manifestation of general differences in reward and punishment sensitivity. Eighty-nine participants (M age=22.4, SD=1.9; 47.2% women) consumed a moderate dose of alcohol, i.e., peak breath alcohol concentration (BrAC)≈0.080g%, and rated their level of stimulation and sedation at seven timepoints over the BrAC curve. Sensitivity to reward and punishment were assessed by a self-report questionnaire prior to consumption. Multilevel growth models showed that post-consumption changes in stimulation ratings varied as a function of participants' level of reward and punishment sensitivity. Drinkers more sensitive to reward reported feeling more stimulated shortly after drinking and exhibited an attenuated rate of decline in stimulation over the blood alcohol curve, relative to drinkers with less strong reward sensitivity. Reward sensitivity was not related to subjective ratings of sedation, and punishment sensitivity was not related to either stimulation or sedation ratings. Findings suggest that reward sensitivity may increase risk for alcohol misuse among young adult social drinkers by increasing their subjective feelings of stimulation while drinking.

The natural history of substance use disorders

PURPOSE OF REVIEW

Illicit drugs, alcohol, and tobacco use disorders contribute substantially to the global burden of disease. Knowledge about the major elements of the natural history of substance use disorders (incidence, remission, persistence, and relapse) is crucial to a broader understanding of the course and outcomes of substance use disorders.

RECENT FINDINGS

Prospective cohort studies in nonclinical samples indicate that externalizing psychopathology in earlier life, including early disordered substance use, delinquency, and personality disorders, are related to substance use disorders later in life and chronic course. Externalizing psychopathology may be initiated by early adverse experiences, for example, childhood maltreatment and stressful life events. After controlling for confounders, 'age at first use' as a causal factor for alcohol use disorder later in life and the 'drug substitution' hypothesis are not supported in general population data.

SUMMARY

Future research should focus on elaborating the causal framework that leads to the development and persistence of severe substance use disorders, with an emphasis on identifying modifiable factors for intervention by policy makers or health professionals. More research is needed on the natural history of substance use disorders in low-income and middle-income countries.

Alcohol resistance in Drosophila is modulated by the Toll innate immune pathway

A growing body of evidence has shown that alcohol alters the activity of the innate immune system and that changes in innate immune system activity can influence alcohol-related behaviors. Here, we show that the Toll innate immune signaling pathway modulates the level of alcohol resistance in Drosophila. In humans, a low level of response to alcohol is correlated with increased risk of developing an alcohol use disorder. The Toll signaling pathway was originally discovered in, and has been extensively studied in Drosophila. The Toll pathway is a major regulator of innate immunity in Drosophila, and mammalian Toll-like receptor signaling has been implicated in alcohol responses. Here, we use Drosophila-specific genetic tools to test eight genes in the Toll signaling pathway for effects on the level of response to ethanol. We show that increasing the activity of the pathway increases ethanol resistance whereas decreasing the pathway activity reduces ethanol resistance. Furthermore, we show that gene products known to be outputs of innate immune signaling are rapidly induced following ethanol exposure. The interaction between the Toll signaling pathway and ethanol is rooted in the natural history of Drosophila melanogaster.

Subjective response as a consideration in the pharmacogenetics of alcoholism treatment

Currently available pharmacological treatments for alcoholism have modest efficacy and high individual variability in treatment outcomes, both of which have been partially attributed to genetic factors. One path to reducing the variability and improving the efficacy associated with these pharmacotherapies may be to identify overlapping genetic contributions to individual differences in both subjective responses to alcohol and alcoholism pharmacotherapy outcomes. As acute subjective response to alcohol is highly predictive of future alcohol related problems, identifying such shared genetic mechanisms may inform the development of personalized treatments that can effectively target converging pathophysiological mechanisms that convey risk for alcoholism. The focus of this review is to revisit the association between subjective response to alcohol and the etiology of alcoholism while also describing genetic contributions to this relationship, discuss potential pharmacogenetic approaches to target subjective response to alcohol in order to improve the treatment of alcoholism and examine conceptual and methodological issues associated with these topics, and outline future approaches to overcome these challenges.

No differences in ventral striatum responsivity between adolescents with a positive family history of alcoholism and controls

Individuals with alcohol-dependent parents show an elevated risk of developing alcohol-related problems themselves. Modulations of the mesolimbic reward circuit have been postulated as a pre-existing marker of alcoholism. We tested whether a positive family history of alcoholism is correlated with ventral striatum functionality during a reward task. All participants performed a modified version of the monetary incentive delay task while their brain responses were measured with functional magnetic resonance imaging. We compared 206 healthy adolescents (aged 13-15) who had any first- or second-degree relative with alcoholism to 206 matched controls with no biological relative with alcoholism. Reward anticipation as well as feedback of win recruited the ventral striatum in all participants, but adolescents with a positive family history of alcoholism did not differ from their matched peers. Also we did not find any correlation between family history density and reward anticipation or feedback of win. This finding of no differences did not change when we analyzed a subsample of 77 adolescents with at least one parent with alcohol use disorder and their matched controls. Because this result is in line with another study reporting no differences between children with alcohol-dependent parents and controls at young age, but contrasts with studies of older individuals, one might conclude that at younger age the effect of family history has not yet exerted its influence on the still developing mesolimbic reward circuit.

Socio-contextual factors are linked to differences in the course of problem drinking in midlife: A discordant-twin study

BACKGROUND

Course of alcohol use disorders (AUD) during midlife is understudied, and most research designs are unable to attribute an unambiguous environmental explanation to observed findings.

OBJECTIVES & METHODS

Test whether socio-contextual factors are linked to differences in the course of problem drinking during midlife. Participants were 163 monozygotic and dizygotic twin pairs concordant for a history of AUD but discordant on problem drinking in the past 10 years.

RESULTS

Frequency of drinking with spouse, and peer and emotional problems were associated with discordance.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

Socio-contextual factors are linked to differences in course of problem drinking in midlife and are not confounded by genetic effects. (Am J Addict 2015;24:193-196).

The evidence for the contribution of the autism susceptibility candidate 2 (AUTS2) gene in heroin dependence susceptibility

The single-nucleotide polymorphisms (SNP) rs6943555 in autism susceptibility candidate 2 (AUTS2) has been reported to be significantly associated with alcohol consumption in Europeans. In this study, we identified the SNP in AUTS2 contributing to the genetic susceptibility to heroin dependence. The potential association between heroin dependence and 21 SNPs (rs2270162, rs2851510, rs513150, rs595681, rs210606, rs10237984, rs13228123, rs10235781, rs6969375, rs6943555, rs10251416, rs17141963, rs12669427, rs723340, rs2293507, rs2293508, rs6960426, rs9886351, rs2293501, rs10277450, rs1918425) of AUTS2 was examined in a Chinese Han population using the MassARRAY system. The participants included 426 patients with heroin dependence and 416 healthy controls. Single SNP association, haplotype association, and clinical phenotype association were analyzed. Single SNP association revealed that AA homozygotes of rs6943555 were significantly over-represented in the patients with heroin dependence compared with the control subjects (P=0.0019). The patients with heroin dependence had a significantly higher frequency of the A allele (P=0.0003, odd ratio (OR)=1.429, 95% confidence interval (CI)=1.175-1.738). Strong linkage disequilibrium (LD) was observed in five blocks (D'>0.9). In block 2, significantly more A-A haplotypes (P=0.006 after Bonferroni corrections) and significantly fewer T-A haplotypes (P=0.040) were found in the patients with heroin dependence. The genotype and clinical phenotype correlation study of the rs6943555 carriers showed that the amount of heroin self-injection was lower in the patients with the AA genotype relative to AT+TT genotypes (P<0.01). Our results confirmed that, in addition to heroin consumption, the SNP rs6943555 of AUTS2 may also play an important role in the etiology of heroin dependence.

Predictors of subgroups based on maximum drinks per occasion over six years for 833 adolescents and young adults in COGA

OBJECTIVE

A person's pattern of heavier drinking often changes over time, especially during the early drinking years, and reflects complex relationships among a wide range of characteristics. Optimal understanding of the predictors of drinking during times of change might come from studies of trajectories of alcohol intake rather than cross-sectional evaluations.

METHOD

The patterns of maximum drinks per occasion were evaluated every 2 years between the average ages of 18 and 24 years for 833 subjects from the Collaborative Study on the Genetics of Alcoholism. Latent class growth analysis identified latent classes for the trajectories of maximum drinks, and then logistic regression analyses highlighted variables that best predicted class membership.

RESULTS

Four latent classes were found, including Class 1 (69%), with about 5 maximum drinks per occasion across time; Class 2 (15%), with about 9 drinks at baseline that increased to 18 across time; Class 3 (10%), who began with a maximum of 18 drinks per occasion but decreased to 9 over time; and Class 4 (6%), with a maximum of about 22 drinks across time. The most consistent predictors of higher drinking classes were female sex, a low baseline level of response to alcohol, externalizing characteristics, prior alcohol and tobacco use, and heavier drinking peers.

CONCLUSIONS

Four trajectory classes were observed and were best predicted by a combination of items that reflected demography, substance use, level of response and externalizing phenotypes, and baseline environment and attitudes.

The patterns of drug and alcohol use and associated problems over 30 years in 397 men

BACKGROUND

Alcohol and drug use disorders (AUDs and SUDs) and their combination are relatively common and often occur together. However, the relationships of potential early life correlates of alcohol and drug disorders to the combined diagnoses have rarely been evaluated in long-term prospective studies or in populations at high risk of one of these diagnoses but not the other.

METHODS

Data were analyzed from 397 males (half with an alcohol-dependent father) who had no AUDs or SUDs at age 20 and who were followed approximately every 5 years for 3 decades. Early life correlates and the course of AUDs, SUDs, and combined disorders were evaluated for 4 groups of subjects based on subsequent alcohol and/or drug diagnoses.

RESULTS

While the overall rates of the development of AUDs and SUDs were 41 and 21%, respectively, the rates of the second substance-related diagnosis were almost 2-fold higher for individuals who had the first condition. Among potential risk factors, scores for externalizing traits were elevated for men with AUDs, SUDs, and their combination, but a low level of response (low LR) to alcohol was associated only with the risk of AUDs, even when observed in the context of SUDs. The same earlier life characteristics that related to AUDs and to SUDs also related to the combination of these diagnoses in the same person. Finally, in this prospective study, subjects with both AUDs and SUDs had a more severe course than subjects with either condition alone.

CONCLUSIONS

This prospective evaluation of a group at high risk of AUDs confirmed the selective impact of the low LR on the risk of AUDs, the relationship of externalizing characteristics to both AUDs and SUDs and confirmed the more severe clinical course for both conditions when seen together.

A 26-year follow-up study of heavy drinking trajectories from adolescence to mid-adulthood and adult disadvantage

AIMS

The aim of the study was to identify heavy drinking trajectories from age 16 to 42 years and to examine their associations with health, social, employment and economic disadvantage in mid-adulthood.

METHODS

Finnish cohort study's participants who were 16 years old in 1983 were followed up at age 22, 32 and 42 (n = 1334). Heavy drinking was assessed at every study phase and based on these measurements trajectories of heavy drinking were identified. The trajectory groups were then examined as predictors of disadvantage at age 42.

RESULTS

Five distinct heavy drinking trajectories were identified: moderate (35%), steady low (22%), decreasing (9%), increasing (11%) and steady high (23%). Frequencies of the trajectory groups differed by gender. Using the moderate trajectory as a reference category, women in the steady high trajectory had an increased risk of experiencing almost all disadvantages at age 42. In men, increasing and steady high groups had an increased risk for experiencing health and economic disadvantage.

CONCLUSION

Steady high female drinkers and steady high and increasing male drinkers had the highest risk for disadvantage in mid-adulthood. By identifying heavy drinking trajectories from adolescence to mid-adulthood we can better predict long-term consequences of heavy alcohol use and plan prevention and intervention programmes.

Examination of rare missense variants in the CHRNA5-A3-B4 gene cluster to level of response to alcohol in the San Diego Sibling Pair study

BACKGROUND

Common variants in the CHRNA5-A3-B4 gene cluster have been shown to be associated with nicotine dependence and alcohol use disorders (AUDs) and related traits, including the level of response (LR) to alcohol. Recently, rare variants (MAF < 0.05) in CHRNB4 have been reported to be associated with a decreased risk of developing nicotine dependence. However, the role of rare variants in the CHRNA5-A3-B4 gene cluster to the LR to alcohol has not yet been established.

METHODS

To determine whether rare variants in the CHRNA5-A3-B4 gene cluster contribute to the LR to alcohol, the coding regions of these 3 genes were sequenced in 538 subjects from the San Diego Sibling Pair study.

RESULTS

The analyses identified 16 rare missense variants, 9 of which were predicted to be damaging using in silico analysis tools. Carriers of these variants were compared to noncarriers using a family-based design for each gene and for the gene cluster as a whole. In these analyses, a CHRNA5 carrier status was significantly associated with the phenotype related to the feeling of intoxication experienced during the alcohol challenge (p = 0.039).

CONCLUSIONS

These results indicate that rare genetic variation in the CHRNA5-A3-B4 gene cluster contributes modestly to the LR to alcohol in the San Diego Sibling Pair study and may protect against AUDs. However, replication studies are needed to confirm our findings.

Predictors of initial and sustained remission from alcohol use disorders: findings from the 30-year follow-up of the San Diego Prospective Study

BACKGROUND

Individuals who report problematic drinking early in life often recover from alcohol-related disorders, with or without formal treatment. While risk factors associated with developing alcohol use disorders (AUDs), such as a family history of alcoholism and the genetically influenced low level of response (LR) to alcohol, have been identified, less is known about characteristics that relate to remission from AUDs.

METHODS

The male subjects (98% Caucasian) for this study were 129 probands from the San Diego Prospective Study who were first evaluated at age 20 as drinking but not alcohol-dependent young men, most of whom were college graduates by follow-up. The individuals evaluated here met criteria for an AUD at their first follow-up at ages 28 to 33 and were followed every 5 years for the next 2 decades. Discrete-time survival analysis was used to examine rates of initial and sustained AUD remission and to evaluate the relationships of premorbid characteristics and other risk factors to these outcomes.

RESULTS

Sixty percent of the sample met criteria for an initial AUD remission of 5 or more years, including 45% with sustained remission (i.e., no subsequent AUD diagnosis). Higher education, lower drinking frequency, and having a diagnosis of alcohol abuse (rather than dependence) were associated with higher rates of initial AUD remission. A lower LR to alcohol at age 20, as well as lower drinking frequency, having received formal alcohol treatment, and older age at the first follow-up all predicted a greater likelihood of sustained AUD remission.

CONCLUSIONS

This study identified key factors associated with initial and sustained AUD remission in subjects diagnosed with AUD in young adulthood. Characteristics associated with better outcomes early in the life span, such as lower drinking frequency and early treatment, appear to have a lasting impact on remission from AUD across adulthood.

The β2 nicotinic acetylcholine receptor subunit differentially influences ethanol behavioral effects in the mouse

The high co-morbidity between alcohol (ethanol) and nicotine abuse suggests that nicotinic acetylcholine receptors (nAChRs), thought to underlie nicotine dependence, may also be involved in alcohol dependence. The β2* nAChR subtype serves as a potential interface for these interactions since they are the principle mediators of nicotine dependence and have recently been shown to modulate some acute responses to ethanol. Therefore, the aim of this study was to more fully characterize the role of β2* nAChRs in ethanol-responsive behaviors in mice after acute exposure to the drug. We conducted a battery of tests in mice lacking the β2* coding gene (Chrnb2) or pretreated with a selective β2* nAChR antagonist for a range of ethanol-induced behaviors including locomotor depression, hypothermia, hypnosis, and anxiolysis. We also tested the effect of deletion on voluntary escalated ethanol consumption in an intermittent access two-bottle choice paradigm to determine the extent of these effects on drinking behavior. Our results showed that antagonism of β2* nAChRs modulated some acute behaviors, namely by reducing recovery time from hypnosis and enhancing the anxiolytic-like response produced by acute ethanol in mice. Chrnb2 deletion had no effect on ethanol drinking behavior, however. We provide further evidence that β2* nAChRs have a measurable role in mediating specific behavioral effects induced by acute ethanol exposure without affecting drinking behavior directly. We conclude that these receptors, along with being key components in nicotine dependence, may also present viable candidates in the discovery of the molecular underpinnings of alcohol dependence.

Genetic analysis of AUTS2 as a susceptibility gene of heroin dependence

BACKGROUND

Both alcoholism and heroin dependence are common substance use disorders with a high genetic basis. A recent genetic study reported that the autism susceptibility candidate 2 gene (AUTS2) was involved in regulating the alcohol drinking behavior. In our previous total gene expression profiling study, we found that the AUTS2 transcript was significantly down-regulated in lymphoblastoid cell lines (LCL) in heroin dependent individuals compared with control subjects, which prompted us to investigate whether AUTS2 is associated with heroin dependence.

METHODS

We compared the AUTS2 transcript level of LCL between 124 heroin dependent males and 116 control males using real-time quantitative PCR, and conducted a genetic association study of the rs6943555 of AUTS2 with heroin dependence using a sample of 546 heroin dependent males and 373 control males.

RESULTS

We first verified that the average transcript level of AUTS2 in the heroin dependent group was significantly lower than that in the control group (p=0.017). In the genetic association analysis, we found that AA homozygotes of rs6943555 were significantly over-represented in the heroin dependent subjects compared with the control subjects (odds ratio=1.7, 95% confidence interval: 1.08-2.74, p=0.017). Analyzing the sample from the AUTS2 transcript experiment, we found that AA carriers (n=19) had significantly lower AUTS2 mRNA levels in their LCL compared to TT carriers (n=97, p=0.002) and AT carriers (n=91, p=0.005).

CONCLUSIONS

Our data indicate that the AUTS2 gene might be associated with heroin dependence, and reduced AUTS2 gene expression might confer increased susceptibility to heroin dependence.

Stability of scores and correlations with drinking behaviors over 15 years for the Self-Report of the Effects of Alcohol Questionnaire

BACKGROUND

The low level of response (LR) to alcohol is an endophenotype that predicts future heavy drinking and alcohol use disorders (AUDs). LR can be measured by laboratory-based alcohol challenges or by the retrospective Self-Report of the Effects of Alcohol (SRE) questionnaire. This paper reports the relationships among these two measures and how each related to both recent and future drinking quantities and problems across 15 years in 235 men.

METHODS

Probands from the San Diego Prospective Study (SDPS) participated in alcohol challenges to determine their LR at age 20, and subsequently at ages 35, 40, 45 and 50 filled out an SRE regarding the number of standard drinks needed for up to four effects early in life (SRE5) and across early, recent, and heaviest drinking life epochs (SRET). Changes in SRE scores across time were evaluated with ANOVAs and Pearson correlations were used to evaluate how SRE5, SRET and earlier alcohol challenge-based LRs related to prior five-year drinking histories and future alcohol involvement.

RESULTS

While SRE scores decreased 9% over the 15 years, the relationships between SRE values with prior five-year drinking parameters and with future alcohol intake and problems remained robust, and even improved with advancing age. A similar pattern was seen for correlations between SRE and alcohol challenge-based LRs 15-30 years previously.

CONCLUSIONS

Alcohol challenge and SRE-based LRs related to each other, to alcohol use patterns, and to future alcohol problems across age 35-50 in the men studied here.

Alcohol increases impulsivity and abuse liability in heavy drinking women

Heavy drinking has increased in recent years and has been linked to numerous health-related risks, particularly in women. A number of factors may play a role in exacerbating the risks linked to heavy drinking, such as impulsivity, which itself is related to a number of risky behaviors. The present study investigated the effects of alcohol (0, 0.5, 0.75 g/kg) on impulsivity in female heavy drinkers (n = 23) and female light drinkers (n = 23) using a double-blind, placebo-controlled outpatient design; all women were tested during follicular phase of the menstrual cycle. Each session, participants completed a range of tasks including subjective measures of abuse liability, cognitive performance tasks, three behavioral impulsivity tasks, and a risk-taking task. Alcohol increased impulsivity on the Immediate and Delayed Memory Task (IMT and DMT) and Delay Discounting task. Heavy drinkers scored higher on impulsivity self-reports and were more impulsive on the IMT and the GoStop task than light drinkers. The high dose of alcohol further increased impulsive performance on the IMT and DMT in heavy drinkers. There were no group differences or alcohol effects on the Balloon Analogue Risk Task. Alcohol increased sedative-like effects more in light drinkers and increased stimulant-like effects and alcohol liking more in heavy drinkers. In summary, female heavy drinkers are less sensitive to the negative effects of alcohol, report more positive effects of alcohol, and are more impulsive than female light drinkers. Moreover, impulsive responding was exacerbated by alcohol drinking among female heavy drinkers, indicating that women who drink at this level are at increased risk for developing alcohol use disorders and engaging in other risky behaviors, particularly after drinking.

Associations between behavioral disinhibition and cocaine use history in individuals with cocaine dependence

BACKGROUND

Behavioral disinhibition has been suggested as both a cause and consequence of substance use disorders. Many studies examining associations between behavioral disinhibition and substance use history have focused on individuals with alcohol dependence or non-dependent college students. In the present study, the relationship between behavioral disinhibition and cocaine use history in individuals with cocaine dependence is examined.

METHODS

Forty-six non-treatment-seeking cocaine-dependent men and women completed impulsivity (Barratt impulsiveness scale; BIS) and novelty seeking (temperament and character inventory; TCI) questionnaires at the baseline visit of an ongoing study. Unadjusted, and adjusted for gender and age, Pearson correlations were calculated between BIS, TCI, and cocaine use variables from the structured clinical interview for DSM-IV and timeline follow-back (age of onset, quantity/frequency of past 30 day cocaine use).

RESULTS

As expected, elevated motor impulsivity and novelty seeking were each associated with younger age of dependence onset. Also, individuals with lower levels of persistence on the TCI reported more days of cocaine use over the previous month. Unexpectedly, increased novelty seeking and attentional impulsivity were associated with fewer days of cocaine use and less money spent on cocaine, respectively. Controlling for age and gender did not substantially change the pattern of observed associations.

CONCLUSIONS

The present study provides preliminary evidence for associations between behavioral disinhibition and cocaine use history in cocaine-dependent individuals. Given our relatively small sample size and the correlational nature of our findings, further research is needed to replicate and extend our results.

Nicotine dependence among clients receiving publicly funded substance abuse treatment

BACKGROUND

Smoking and nicotine dependence (ND) are prevalent among substance abusers but little is known about characteristics of ND in this population. This information would help identify those most in need of smoking cessation programs. This study evaluated the associations of socio-demographic, tobacco- and substance use-related, and health/mental health factors to ND in adults receiving publicly funded substance abuse treatment in Tennessee.

METHODS

All Tennessee residents who received federal block grant-funded substance abuse treatment during July-December, 2004 were invited to participate in a 6 month post-intake telephone follow-up interview. Socio-demographic characteristics, perceived health and mental health, tobacco use history and patterns, and ND, assessed by the Fagerstrom Test of Nicotine Dependence (FTND), were obtained at follow-up. Alcohol and illicit drug use and smoking status prior to treatment were assessed at intake. This paper analyzes data for 855 clients who were current cigarette smokers at both intake and follow-up.

RESULTS

Sixty three percent of smokers were ND (FTND score ≥ 4). Correlates of ND included older age, poorer self-rated overall health, earlier age of onset of cigarette smoking and substance abuse, fewer smoking quit attempts in past year, single substance use (alcohol or illicit drug, vs. multiple substances) at intake, use of opiates/narcotics and sedatives, and past month self-reported depression.

CONCLUSION

ND was highly prevalent and correlated with specific types and patterns of substance abuse and depression. These results suggest that intensive smoking cessation interventions, involving behavioral support, pharmacotherapy, and mood management, are needed to effectively assist this population.

Reduced subjective response to acute ethanol administration among young men with a broad bipolar phenotype

Elevated lifetime prevalence rates of alcohol use disorders (AUDs) are a feature of bipolar disorder (BD). Individuals at-risk for AUDs exhibit blunted subjective responses to alcohol (low levels of response), which may represent a biomarker for AUDs. Thus, individuals at-risk for BD may exhibit low responses to alcohol. Participants were 20 unmedicated adult males who reported high rates of hypomanic experiences (bipolar phenotype participants; BPPs), aged 18 to 21 years, and 20 healthy controls matched on age, gender, IQ, BMI, and weekly alcohol intake. Subjective and pharmacokinetic responses to acute alcohol (0.8 g/kg) vs placebo administration were collected in a randomized, double-blind, cross-over, placebo-controlled, within-subjects design. BPP participants reported significantly lower subjective intoxication effects ('feel high': F=14.2, p=0.001; 'feel effects': F=8.1, p=0.008) across time, but did not differ in their pharmacokinetic, stimulant, or sedative responses. Paradoxically, however, the BPP participants reported significantly higher expectations of the positive effects of alcohol than controls. Our results suggest that unmedicated young males with previous hypomanic experiences exhibit diminished subjective responses to alcohol. These blunted alcohol responses are not attributable to differences in weekly alcohol intake, pharmacokinetic effects (eg, absorption rates), or familial risk of AUDs. These observations suggest that the dampened intoxication may contribute to the increased rates of alcohol misuse in young people at-risk for BD, and suggest possible shared etiological factors in the development of AUDs and BD.

Comparison across two generations of prospective models of how the low level of response to alcohol affects alcohol outcomes

OBJECTIVE

This article presents the first direct comparison of level of response (LR)-based prospective models in two generations of the same families. To accomplish this, we describe results from the first prospective evaluation of potential mediators of how an earlier low LR to alcohol relates to adverse alcohol outcomes in offspring from the San Diego Prospective Study (SDPS).

METHOD

To compare with data from probands in the SDPS, new data were gathered from 86 drinking offspring (age ~20 years) during the 25-year follow-up of these families. Consistent with the usual effect of a low LR, outcomes 5 years later for both generations focused on drinking quantities as well as alcohol problems during the follow-up. A structural equation model (SEM) was used to analyze the relationships among variables, and the models in proband and offspring generations were compared using direct observations of the model results and through invariance procedures.

RESULTS

In these drinking offspring, LR correlated with 5-year outcomes (r = .48, p < .001) and the SEM R² was .48, with good fit statistics. As predicted, the LR relationship to alcohol-related outcomes was both direct and partially mediated by heavier peer drinking, positive alcohol expectancies, and using alcohol to cope with stress. These results were similar to a previously published prospective model in SDPS probands, although path coefficients were generally higher in the younger group.

CONCLUSIONS

The LR-based model of heavier drinking operated similarly across generations, with some modest differences. These results indicate that the model may be meaningful in both younger and middle-age groups.

Correlates of recovery from alcohol dependence: a prospective study over a 3-year follow-up interval

BACKGROUND

Correlates of recovery from alcohol dependence have been identified through a variety of study designs characterized by different strengths and limitations. The goal of this study was to compare correlates of recovery based on a 3-year prospective design with those based on cross-sectional analyses of data from the same source.

METHODS

Data from the 2001 to 2002 Wave 1 and 2004 to 2005 Wave 2 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were used to examine baseline characteristics associated with Wave 2 recovery from alcohol dependence, among those who classified with past-year DSM-IV alcohol dependence at Wave 1 (n = 1,172).

RESULTS

Abstinent recovery was significantly associated with Black/Asian/Hispanic race/ethnicity, children <1 year of age in the household at baseline, attending religious services greater than or equal to weekly at follow-up, and having initiated help-seeking that comprised/included 12-step participation within <3 years prior to baseline. Nonabstinent recovery was positively associated with being never married at baseline, having job problems or being unemployed in the year preceding baseline, attending religious services less than weekly at follow-up, baseline smoking and volume of ethanol intake, and having terminated a first marriage within <3 years prior to baseline. Findings, including others of marginal significance (0.05 < p < 0.10), generally supported results from prior pseudo-prospective survival analyses with time-dependent covariates but differed in many ways from cross-sectional analyses of Wave 1 NESARC data.

CONCLUSIONS

Various aspects of study design must be considered when interpreting correlates of recovery. Cross-sectional analyses of lifetime correlates of recovery are highly subject to misinterpretation, but pseudo-prospective survival analyses with time-dependent covariates may yield results as valid as those from prospective studies.

Genome-wide association for methamphetamine sensitivity in an advanced intercross mouse line

Sensitivity to the locomotor stimulant effects of methamphetamine (MA) is a heritable trait that utilizes neurocircuitry also associated with the rewarding effects of drugs. We used the power of a C57BL/6J × DBA/2J F(2) intercross (n = 676) and the precision of a C57BL/6J × DBA/2J F(8) advanced intercross line (Aap: B6, D2-G8; or F(8) AIL; n = 552) to identify and narrow quantitative trait loci (QTLs) associated with sensitivity to the locomotor stimulant effects of MA. We used the program QTLRel to simultaneously map QTL in the F(2) and F(8) AIL mice. We identified six genome-wide significant QTLs associated with locomotor activity at baseline and seven genome-wide significant QTLs associated with MA-induced locomotor activation. The average per cent decrease in QTL width between the F(2) and the integrated analysis was 65%. Additionally, these QTLs showed a distinct temporal specificity within each session that allowed us to further refine their locations, and identify one QTL with a 1.8-LOD support interval of 1.47 Mb. Next, we utilized publicly available bioinformatics resources to exploit strain-specific sequence data and strain- and region-specific expression data to identify candidate genes. These results illustrate the power of AILs in conjunction with sequence and gene expression data to investigate the genetic underpinnings of behavioral and other traits.

Continuing care and long-term substance use outcomes in managed care: early evidence for a primary care-based model

OBJECTIVES

How best to provide ongoing services to patients with substance use disorders to sustain long-term recovery is a significant clinical and policy question that has not been adequately addressed. Analyzing nine years of prospective data for 991 adults who entered substance abuse treatment in a private, nonprofit managed care health plan, this study aimed to examine the components of a continuing care model (primary care, specialty substance abuse treatment, and psychiatric services) and their combined effect on outcomes over nine years after treatment entry.

METHODS

In a longitudinal observational study, follow-up measures included self-reported alcohol and drug use, Addiction Severity Index scores, and service utilization data extracted from the health plan databases. Remission, defined as abstinence or nonproblematic use, was the outcome measure.

RESULTS

A mixed-effects logistic random intercept model controlling for time and other covariates found that yearly primary care, and specialty care based on need as measured at the prior time point, were positively associated with remission over time. Persons receiving continuing care (defined as having yearly primary care and specialty substance abuse treatment and psychiatric services when needed) had twice the odds of achieving remission at follow-ups (p<.001) as those without.

CONCLUSIONS

Continuing care that included both primary care and specialty care management to support ongoing monitoring, self-care, and treatment as needed was important for long-term recovery of patients with substance use disorders.

Is alcohol dependence best viewed as a chronic relapsing disorder?

This 'For Debate' paper starts by recognizing the growing trend towards considering alcohol dependence as a chronic relapsing disorder. We argue that the adoption of this model results from focusing on those in treatment for alcohol dependence rather than considering the larger number of people in the general population who meet criteria for alcohol dependence at some point in their lives. The majority of the general population who ever experience alcohol dependence do not behave as though they have a chronic relapsing disorder: they do not seek treatment, resolve their dependence themselves and do not relapse repeatedly. We suggest that caution is therefore needed in using the chronic relapsing disorder label. Our primary concerns are that this formulation privileges biological aspects of dependence to the detriment of psychological and social contributions, it inhibits much-needed developments in understanding alcohol dependence and leads to inefficient distributions of public health and clinical care resources for alcohol dependence. We invite debate on this issue.

Continuing care and long-term substance use outcomes in managed care: early evidence for a primary care-based model

OBJECTIVES

How best to provide ongoing services to patients with substance use disorders to sustain long-term recovery is a significant clinical and policy question that has not been adequately addressed. Analyzing nine years of prospective data for 991 adults who entered substance abuse treatment in a private, nonprofit managed care health plan, this study aimed to examine the components of a continuing care model (primary care, specialty substance abuse treatment, and psychiatric services) and their combined effect on outcomes over nine years after treatment entry.

METHODS

In a longitudinal observational study, follow-up measures included self-reported alcohol and drug use, Addiction Severity Index scores, and service utilization data extracted from the health plan databases. Remission, defined as abstinence or nonproblematic use, was the outcome measure.

RESULTS

A mixed-effects logistic random intercept model controlling for time and other covariates found that yearly primary care, and specialty care based on need as measured at the prior time point, were positively associated with remission over time. Persons receiving continuing care (defined as having yearly primary care and specialty substance abuse treatment and psychiatric services when needed) had twice the odds of achieving remission at follow-ups (p<.001) as those without.

CONCLUSIONS

Continuing care that included both primary care and specialty care management to support ongoing monitoring, self-care, and treatment as needed was important for long-term recovery of patients with substance use disorders.

Comment on the paper by Quinn and Fromme entitled subjective response to alcohol challenge: a quantitative review

BACKGROUND

This commentary discusses the recent paper by Quinn and Fromme (2011), placing their results into perspective.

RESULTS

Quinn and Fromme's meta-analysis is an important and useful synthesis of a complex literature. It is clear, well written, and well reasoned, with conclusions that are relevant to both the Low Level of Response Model and the Differentiator Model.

CONCLUSIONS

Drs. Quinn and Fromme use a thorough and thoughtful approach, and I encourage researchers to address the important questions raised by their meta-analysis.

Genome-wide association and genetic functional studies identify autism susceptibility candidate 2 gene (AUTS2) in the regulation of alcohol consumption

Alcohol consumption is a moderately heritable trait, but the genetic basis in humans is largely unknown, despite its clinical and societal importance. We report a genome-wide association study meta-analysis of ∼2.5 million directly genotyped or imputed SNPs with alcohol consumption (gram per day per kilogram body weight) among 12 population-based samples of European ancestry, comprising 26,316 individuals, with replication genotyping in an additional 21,185 individuals. SNP rs6943555 in autism susceptibility candidate 2 gene (AUTS2) was associated with alcohol consumption at genome-wide significance (P = 4 × 10(-8) to P = 4 × 10(-9)). We found a genotype-specific expression of AUTS2 in 96 human prefrontal cortex samples (P = 0.026) and significant (P < 0.017) differences in expression of AUTS2 in whole-brain extracts of mice selected for differences in voluntary alcohol consumption. Down-regulation of an AUTS2 homolog caused reduced alcohol sensitivity in Drosophila (P < 0.001). Our finding of a regulator of alcohol consumption adds knowledge to our understanding of genetic mechanisms influencing alcohol drinking behavior.