Sports participation moderates the risk of family-specific negative life events on alcohol use among adolescents: Evidence from the longitudinal MyLife study

Negative life events (NLE) have been associated with increased alcohol use (AU) during adolescence. However, whether this risk association may be modified by leisure activities such as sports participation (SP) remains poorly understood. This study examined whether accumulated family-specific NLE in particular were associated with greater AU, and if so, whether SP moderated this association to reduce AU among high-NLE adolescents. We examined five annual assessments from a nationwide cohort of 3,422 Norwegian adolescents (13-15 year-olds; 55.3 % girls at baseline) who participated in the MyLife study. At each assessment, adolescents reported their AU on the Alcohol Use Disorders Identification Test-Concise (AUDIT-C), the number of family-specific NLE in the past 12 months, SP days in the past 30 days, and multiple sociodemographic and individual-level characteristics (covariates). Changes over time in AU as a function of NLE, SP, and their interaction (NLExSP) were examined with a set of partially nested growth curve models. AU increased non-linearly over time in all models. The fully adjusted best-fitting model showed significant NLExSP interactions (estimate = -0.013, 95% CI [-0.02, -0.006]), such that the initial AUDIT-C scores were lower for high-NLE adolescents with high SP and greater for high-NLE adolescents with low SP. Further, linear increases in AU over time were marginally steeper for high-NLE adolescents with high SP (NLExSPxTime estimate = 0.034, 95% CI [-0.0002, 0.007]). Thus, SP appeared to have a protective role in reducing AU for high-NLE youth primarily during middle school years. Prevention efforts thus may utilize organized sports for youth facing family-specific NLE as a resource early on.

Parameter Space and Potential for Biomarker Development in 25 Years of fMRI Drug Cue Reactivity: A Systematic Review

Importance

In the last 25 years, functional magnetic resonance imaging drug cue reactivity (FDCR) studies have characterized some core aspects in the neurobiology of drug addiction. However, no FDCR-derived biomarkers have been approved for treatment development or clinical adoption. Traversing this translational gap requires a systematic assessment of the FDCR literature evidence, its heterogeneity, and an evaluation of possible clinical uses of FDCR-derived biomarkers.

Objective

To summarize the state of the field of FDCR, assess their potential for biomarker development, and outline a clear process for biomarker qualification to guide future research and validation efforts.

Evidence Review

The PubMed and Medline databases were searched for every original FDCR investigation published from database inception until December 2022. Collected data covered study design, participant characteristics, FDCR task design, and whether each study provided evidence that might potentially help develop susceptibility, diagnostic, response, prognostic, predictive, or severity biomarkers for 1 or more addictive disorders.

Findings

There were 415 FDCR studies published between 1998 and 2022. Most focused on nicotine (122 [29.6%]), alcohol (120 [29.2%]), or cocaine (46 [11.1%]), and most used visual cues (354 [85.3%]). Together, these studies recruited 19 311 participants, including 13 812 individuals with past or current substance use disorders. Most studies could potentially support biomarker development, including diagnostic (143 [32.7%]), treatment response (141 [32.3%]), severity (84 [19.2%]), prognostic (30 [6.9%]), predictive (25 [5.7%]), monitoring (12 [2.7%]), and susceptibility (2 [0.5%]) biomarkers. A total of 155 interventional studies used FDCR, mostly to investigate pharmacological (67 [43.2%]) or cognitive/behavioral (51 [32.9%]) interventions; 141 studies used FDCR as a response measure, of which 125 (88.7%) reported significant interventional FDCR alterations; and 25 studies used FDCR as an intervention outcome predictor, with 24 (96%) finding significant associations between FDCR markers and treatment outcomes.

Conclusions and Relevance

Based on this systematic review and the proposed biomarker development framework, there is a pathway for the development and regulatory qualification of FDCR-based biomarkers of addiction and recovery. Further validation could support the use of FDCR-derived measures, potentially accelerating treatment development and improving diagnostic, prognostic, and predictive clinical judgments.

Does cannabis use substitute for opioids? A preliminary exploratory survey in opioid maintenance patients

Various studies showed that people with substance use disorder use cannabis to reduce withdrawal or dose of their main drug. Using a questionnaire about their cannabis use, 118 participants in an opioid maintenance treatment (OMT) in Germany were examined regarding this strategy. 60% reported to use cannabis. Of those, 72% were using cannabis in the suggested way. Cannabis was used to substitute for, e.g., heroin (44.8%) and benzodiazepines (16.4%). We also asked for an estimation of how good cannabis was able to substitute for several substances (in German school grades (1 till 6)); heroin average grade: 2.6 ± 1.49. Besides that we asked about the idea of cannabis as "self-medication", e.g., to reduce pain (47%) and about negative consequences from cannabis use. Our results suggest to consider the use of cannabis by patients in OMT rather as a harm reduction strategy to reduce the intake of more dangerous drugs.

Alcohol does not influence trust in others or oxytocin, but increases positive affect and risk-taking: a randomized, controlled, within-subject trial

BACKGROUND

Alcohol consumption to facilitate social interaction is an important drinking motive. Here, we tested whether alcohol influences trust in others via modulation of oxytocin and/or androgens. We also aimed at confirming previously shown alcohol effects on positive affect and risk-taking, because of their role in facilitating social interaction.

METHODS

This randomized, controlled, within-subject, parallel group, alcohol-challenge experiment investigated the effects of alcohol (versus water, both mixed with orange juice) on perceived trustworthiness via salivary oxytocin (primary and secondary endpoint) as well as testosterone, dihydrotestosterone, positive affect, and risk-taking (additional endpoints). We compared 56 male participants in the alcohol condition (1.07 ± 0.18 per mille blood alcohol concentration) with 20 in the control condition.

RESULTS

The group (alcohol versus control condition) × time (before [versus during] versus after drinking) interactions were not significantly associated with perceived trustworthiness (η2 < 0.001) or oxytocin (η2 = 0.003). Bayes factors provided also substantial evidence for the absence of these effects (BF01 = 3.65; BF01 = 7.53). The group × time interactions were related to dihydrotestosterone (η2 = 0.018 with an increase in the control condition) as well as positive affect and risk-taking (η2 = 0.027 and 0.007 with increases in the alcohol condition), but not significantly to testosterone.

DISCUSSION

The results do not verify alcohol effects on perceived trustworthiness or oxytocin in male individuals. However, they indicate that alcohol (versus control) might inhibit an increase in dihydrotestosterone and confirm that alcohol amplifies positive affect and risk-taking. This provides novel mechanistic insight into social facilitation as an alcohol-drinking motive.

Cue-exposure treatment influences resting-state functional connectivity-a randomized controlled fMRI study in alcohol use disorder

RATIONALE

Cue-exposure therapy (CET) consists of exposing patients to the cause of their affliction in a controlled environment and after psychological preparation. Ever since it was conceived, it has been suggested as a treatment for different types of behavioural impairments, from anxiety disorders to substance abuse. In the field of addictive behaviour, many different findings have been shown regarding the effectiveness of this therapy.

OBJECTIVES

This study aims to examine the underlying neurobiological mechanisms of the effects of CET in patients with alcohol use disorder using resting-state functional magnetic resonance imaging (rs-fMRI).

METHODS

In a randomized, controlled study, we examined patients after inpatient detoxification as well as healthy controls. Patients underwent nine sessions of CET spaced over 3 weeks. Rs-fMRI was conducted before treatment and 3 weeks after treatment onset in patients, healthy controls received only one rs-fMRI measurement. The final participant sample with complete data included 35 patients in the CET group, 17 patients in the treatment-as-usual group, and 43 HCs.

RESULTS

Our results show differences in the Salience Network when comparing the CET group to the treatment-as-usual group (TAU). Functional connectivity between the anterior cingulate Cortex (ACC) and the insula was increased after CET, whereas it was decreased from ACC to the putamen and globus pallidus. Further, increased connectivity with the precuneus was found in the dorsal attention network after cue exposure treatment.

CONCLUSIONS

These findings suggest that cue exposure therapy changes the resting-state brain connectivity with additional effects to the standard psychotherapy treatment. Hence, our study results suggest why including CET in standard therapies might improve the preparation of patients in front of daily situations.

[Diagnosis and admission center : Establishment and evaluation of an integrated translational infrastructure for clinical psychiatric research]

The routine in-depth characterization of patients with methods of clinical and scale-based examination, neuropsychology, based on biomaterials, and sensor-based information opens up transformative possibilities on the way to personalized diagnostics, treatment and prevention in psychiatry, psychotherapy, and psychosomatics. Effective integration of the additional temporal and logistical effort into everyday care as well as the acceptance by patients are critical to the success of such an approach but there is little evidence on this to date. We report here on the establishment of the Diagnosis and Admission Center (DAZ) at the Central Institute of Mental Health (ZI) in Mannheim. The DAZ is an outpatient unit upstream of other care structures for clinical and scientific phenotyping across diagnoses as a starting point for data-driven, individualized pathways to further treatment, diagnostics or research. We describe the functions, goals, and implementation of the newly created clinical scientific translational structure, provide an overview of the patient populations it has reached, and provide data on its acceptance. In this context, the close integration with downstream clinical processes enables a better coordinated and demand-oriented allocation. In addition, DAZ enables a faster start of disorder-specific diagnostics and treatment. Since its launch in April 2021 up to the end of 2022, 1021 patients underwent psychiatric evaluation at DAZ during a pilot phase. The patient sample corresponded to a representative sample from standard care and the newly established processes were regarded as helpful by patients. In summary, the DAZ uniquely combines the interests and needs of patient with the collection of scientifically relevant data.

Biological aging markers in blood and brain tissue indicate age acceleration in alcohol use disorder

BACKGROUND

Alcohol use disorder (AUD) is associated with increased mortality and morbidity risk. A reason for this could be accelerated biological aging, which is strongly influenced by disease processes such as inflammation. As recent studies of AUD show changes in DNA methylation and gene expression in neuroinflammation-related pathways in the brain, biological aging represents a potentially important construct for understanding the adverse effects of substance use disorders. Epigenetic clocks have shown accelerated aging in blood samples from individuals with AUD. However, no systematic evaluation of biological age measures in AUD across different tissues and brain regions has been undertaken.

METHODS

As markers of biological aging (BioAge markers), we assessed Levine's and Horvath's epigenetic clocks, DNA methylation telomere length (DNAmTL), telomere length (TL), and mitochondrial DNA copy number (mtDNAcn) in postmortem brain samples from Brodmann Area 9 (BA9), caudate nucleus, and ventral striatum (N = 63-94), and in whole blood samples (N = 179) of individuals with and without AUD. To evaluate the association between AUD status and BioAge markers, we performed linear regression analyses while adjusting for covariates.

RESULTS

The majority of BioAge markers were significantly associated with chronological age in all samples. Levine's epigenetic clock and DNAmTL were indicative of accelerated biological aging in AUD in BA9 and whole blood samples, while Horvath's showed the opposite effect in BA9. No significant association of AUD with TL and mtDNAcn was detected. Measured TL and DNAmTL showed only small correlations in blood and none in brain.

CONCLUSIONS

The present study is the first to simultaneously investigate epigenetic clocks, telomere length, and mtDNAcn in postmortem brain and whole blood samples in individuals with AUD. We found evidence for accelerated biological aging in AUD in blood and brain, as measured by Levine's epigenetic clock, and DNAmTL. Additional studies of different tissues from the same individuals are needed to draw valid conclusions about the congruence of biological aging in blood and brain.

Stress-Induced Sensitization of Insula Activation Predicts Alcohol Craving and Alcohol Use in Alcohol Use Disorder

BACKGROUND

Stress and alcohol cues trigger alcohol consumption and relapse in alcohol use disorder. However, the neurobiological processes underlying their interaction are not well understood. Thus, we conducted a randomized, controlled neuroimaging study to investigate the effects of psychosocial stress on neural cue reactivity and addictive behaviors.

METHODS

Neural alcohol cue reactivity was assessed in 91 individuals with alcohol use disorder using a validated functional magnetic resonance imaging (fMRI) task. Activation patterns were measured twice, at baseline and during a second fMRI session, prior to which participants were assigned to psychosocial stress (experimental condition) or a matched control condition or physical exercise (control conditions). Together with fMRI data, alcohol craving and cortisol levels were assessed, and alcohol use data were collected during a 12-month follow-up. Analyses tested the effects of psychosocial stress on neural cue reactivity and associations with cortisol levels, craving, and alcohol use.

RESULTS

Compared with both control conditions, psychosocial stress elicited higher alcohol cue-induced activation in the left anterior insula (familywise error-corrected p < .05) and a stress- and cue-specific dynamic increase in insula activation over time (F22,968 = 2.143, p = .007), which was predicted by higher cortisol levels during the experimental intervention (r = 0.310, false discovery rate-corrected p = .016). Cue-induced insula activation was positively correlated with alcohol craving during fMRI (r = 0.262, false discovery rate-corrected p = .032) and alcohol use during follow-up (r = 0.218, false discovery rate-corrected p = .046).

CONCLUSIONS

Results indicate a stress-induced sensitization of cue-induced activation in the left insula as a neurobiological correlate of the effects of psychosocial stress on alcohol craving and alcohol use in alcohol use disorder, which likely reflects changes in salience attribution and goal-directed behavior.

Associations of Menstrual Cycle and Progesterone-to-Estradiol Ratio With Alcohol Consumption in Alcohol Use Disorder: A Sex-Separated Multicenter Longitudinal Study

OBJECTIVE

Alcohol use disorder (AUD) constitutes a critical public health issue and has sex-specific characteristics. Initial evidence suggests that progesterone and estradiol might reduce or increase alcohol intake, respectively. However, there is a need for a better understanding of how the menstrual cycle in females and the ratio of progesterone to estradiol in females and males influence alcohol use patterns in individuals with AUD.

METHODS

In this sex-separated multicenter longitudinal study, the authors analyzed 12-month data on real-life alcohol use (from 21,460 smartphone entries), menstrual cycle, and serum progesterone-to-estradiol ratios (from 667 blood samples at four individual study visits) in 74 naturally cycling females and 278 males with AUD between 2020 and 2022, using generalized and general linear mixed modeling.

RESULTS

Menstrual cycle phases were significantly associated with binge drinking and progesterone-to-estradiol ratio. During the late luteal phase, females showed a lower predicted binge drinking probability of 13% and a higher predicted marginal mean of progesterone-to-estradiol ratio of 95 compared with during the menstrual, follicular, and ovulatory phases (binge drinking probability and odds ratios vs. late luteal phase, respectively: 17%, odds ratio=1.340, 95% CI=1.031, 1.742; 19%, odds ratio=1.523, 95% CI=1.190, 1.949; and 20%, odds ratio=1.683, 95% CI=1.285, 2.206; difference in progesterone-to-estradiol ratios, respectively: -61, 95% CI=-105.492, -16.095; -78, 95% CI=-119.322, -37.039; and -71, 95% CI=-114.568, -27.534). In males, a higher progesterone-to-estradiol ratio was related to lower probabilities of binge drinking and of any alcohol use, with a 10-unit increase in the hormone ratio resulting in odds ratios of 0.918 (95% CI=0.843, 0.999) and 0.914 (95% CI=0.845, 0.988), respectively.

CONCLUSIONS

These ecologically valid findings suggest that high progesterone-to-estradiol ratios can have a protective effect against problematic alcohol use in females and males with AUD, highlighting the progesterone-to-estradiol ratio as a promising treatment target. Moreover, the results indicate that females with AUD may benefit from menstrual cycle phase-tailored treatments.

Psychometric properties of the German Penn Alcohol Craving Scale

Craving for alcohol is an important diagnostic criterion in alcohol use disorder (AUD) and an established predictor of future relapse. The 5-item Penn Alcohol Craving Scale (PACS) is one of the most widely used questionnaires to quantify craving and has been translated into different languages. It is assumed that the PACS constitutes one factor, although theoretical considerations suggest an additional second factor. We conducted stability and factor analyses (principal component and confirmatory factor analyses) of the German PACS (PACS-G) in samples of patients with AUD from the following three German study sites: Erlangen, N = 188 (mean age: 47.1 years, 43.5% female); Mannheim, N = 440 (45.5 years, 28.6% female); Hannover, N = 107 (48.1 years, 48.6% female). In our samples, the 2-factor solution of the PACS-G version is more stable than the internationally assumed 1-factor solution. The resulting two PACS-G subscores 'difficulty to resist' (items 4 and 5) and 'thoughts about alcohol' (items 1, 2, and 3) have an internal consistency (Cronbach's alpha) of 0.80 ≤ α ≤ 0.90, m = 0.86 and 0.86 ≤ α ≤ 0.91, m = 0.89 with an overlap of R2 = 62%. We found good convergent validity assessed via the Craving Automatized Scale-Alcohol and the Obsessive-Compulsive Drinking Scale, but also correlations with depression and anxiety assessed via the Beck's Depression and Anxiety Inventories. This study is the first to provide evidence for a 2-factor solution ('difficulty to resist' and 'thoughts about alcohol') underlying the PACS-G version.

Effectiveness of Reducing Craving in Alcohol Use Disorder Using a Serious Game (SALIENCE): Randomized Controlled Trial

BACKGROUND

Alcohol use disorder (AUD) has become a major global health problem. Therapy for this condition is still a great challenge. Recently, it has become increasingly evident that computer-based training is a valuable addition to the treatment of addictive disorders.

OBJECTIVE

This study aims to evaluate the web-based serious game SALIENCE (Stop Alcohol in Everyday Life-New Choices and Evaluations) as an add-on therapy for AUD. It combines the cue-exposure therapy approach with elements of decision-making training, enhanced by interactive panoramic images. The effects of SALIENCE training on levels of craving, attention, and cognitive bias are investigated.

METHODS

In a randomized controlled trial, 62 participants with AUD undergoing 3 weeks of an extended alcohol detoxification program were randomly allocated to an intervention and a control group. A total of 49 individuals (mean age 44.04 y; 17/49, 35% female) completed all sessions and were included in the analysis. Only pretreatment data were available from the other 13 patients. Participants answered questionnaires related to alcohol consumption and craving and completed neuropsychological tasks at the beginning of the study and 2 weeks later to evaluate levels of attention and cognitive biases. During the 2-week period, 27 of the participants additionally performed the SALIENCE training for 30 minutes 3 times a week, for a total of 6 sessions.

RESULTS

We observed a significant decrease in craving in both groups: the control group (mean 15.59, SD 8.02 on the first examination day vs mean 13.18, SD 8.38 on the second examination day) and the intervention group (mean 15.19, SD 6.71 on the first examination day vs mean 13.30, SD 8.47 on the second examination day; F1,47=4.31; P=.04), whereas the interaction effect was not statistically significant (F1,47=0.06; P=.80). Results of the multiple linear regression controlling for individual differences between participants indicated a significantly greater decrease in craving (β=4.12; t36=2.34; P=.03) with the SALIENCE intervention. Participants with lower drinking in negative situations reduced their craving (β=.38; t36=3.01; P=.005) more than people with higher drinking in negative situations.

CONCLUSIONS

The general effectiveness of SALIENCE training as an add-on therapy in reducing alcohol craving was not confirmed. Nevertheless, taking into account individual differences (gender, duration of dependence, stress, anxiety, and drinking behavior in different situations), it was shown that SALIENCE training resulted in a larger reduction in craving than without. Notably, individuals who rarely consume alcohol due to negative affect profited the most from SALIENCE training. In addition to the beneficial effect of SALIENCE training, these findings highlight the relevance of individualized therapy for AUD, adapted to personal circumstances such as drinking motivation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03765476; https://clinicaltrials.gov/show/NCT03765476.

Alcohol-induced damage to the fimbria/fornix reduces hippocampal-prefrontal cortex connection during early abstinence

INTRODUCTION

Alcohol dependence is characterized by a gradual reduction in cognitive control and inflexibility to contingency changes. The neuroadaptations underlying this aberrant behavior are poorly understood. Using an animal model of alcohol use disorders (AUD) and complementing diffusion-weighted (dw)-MRI with quantitative immunohistochemistry and electrophysiological recordings, we provide causal evidence that chronic intermittent alcohol exposure affects the microstructural integrity of the fimbria/fornix, decreasing myelin basic protein content, and reducing the effective communication from the hippocampus (HC) to the prefrontal cortex (PFC). Using a simple quantitative neural network model, we show how disturbed HC-PFC communication may impede the extinction of maladaptive memories, decreasing flexibility. Finally, combining dw-MRI and psychometric data in AUD patients, we discovered an association between the magnitude of microstructural alteration in the fimbria/fornix and the reduction in cognitive flexibility. Overall, these findings highlight the vulnerability of the fimbria/fornix microstructure in AUD and its potential contribution to alcohol pathophysiology. Fimbria vulnerability to alcohol underlies hippocampal-prefrontal cortex dysfunction and correlates with cognitive impairment.

The impact of COVID-19 pandemic on mental burden and quality of life in medical students - results of an online survey

Objectives

Changes in academic conditions due to the COVID-19 pandemic are potential stressors for medical students and can make them vulnerable for the development of psychiatric disorders.Previous pandemics had a negative impairment on well-being due to social isolation and the perceived threat, an increase in fear, anger and frustration and an increase in post-traumatic stress disorder among health professionals. Therefore, this study examines the impact of the COVID-19 pandemic on medical students' mental health and possible psychological consequences.

Methods

In this anonymous online survey (online 12/01/2021-03/31/2022), we examined the impact of COVID-19 pandemic on mental health of 561 German medical students aged between 18 und 45 years. Perceived anxiety and burden were assessed retrospectively from spring 2020 to autumn 2021. Changes in symptoms of anxiety and depression were assessed using the Hospital Anxiety and Depression Scale (HADS), quality of life was assessed using the WHO Quality of Life Questionnaire (WHOQOL BREF).

Results

Anxiety and burden showed wavelike courses with higher scores in autumn, winter and spring. The scores for depression and anxiety increased after the outbreak of the COVID-19 pandemic compared to the time before (p<.001). Results of a multifactorial ANOVA showed, that previous psychiatric illness (p<.001), being in the first two years of studies (p=.006), higher burden (p=.013) and greater differences in symptoms of depression (p<.001) were associated with a decreased quality of life in medical students.

Conclusion

The COVID-19 pandemic has a negative impact on mental health of medical students and their actual quality of life. Therefore, medical faculties should establish specific support to prevent the development of psychiatric sequelae probably resulting in long-term medical leaves.

Reward Processing in Alcohol-Dependent Patients and First-Degree Relatives: Functional Brain Activity During Anticipation of Monetary Gains and Losses

BACKGROUND

According to the reward deficiency syndrome and allostatic hypotheses, hyposensitivity of mesocorticolimbic regions to non-alcohol-related stimuli predisposes to dependence or is long-lastingly enhanced by chronic substance use. To date, no study has directly compared mesocorticolimbic brain activity during non-drug reward anticipation between alcohol-dependent, at risk, and healthy subjects.

METHODS

Seventy-five abstinent alcohol-dependent human subjects (mean abstinence duration 957.66 days), 62 healthy first-degree relatives of alcohol-dependent individuals, and 76 healthy control subjects without family history of alcohol dependence performed a monetary incentive delay task. Functional magnetic resonance imaging data of the anticipation phase were analyzed, during which visual cues predicted that fast response to a target would result in monetary gain, avoidance of monetary loss, or a neutral outcome.

RESULTS

During gain anticipation, there were no significant group differences. During loss anticipation, abstinent alcohol-dependent subjects showed lower activity in the left anterior insula compared with healthy control subjects without family history of alcohol dependence only (Montreal Neurological Institute [MNI] -25 19 -5; t₂₀₆ = 4.17, familywise error corrected p = .009). However, this effect was no longer significant when age was included as a covariate. There were no group differences between abstinent alcohol-dependent subjects and healthy first-degree relatives or between healthy first-degree relatives and healthy control subjects during loss anticipation, respectively.

CONCLUSIONS

Neither the neural reward deficiency syndrome nor the allostatic hypotheses are supported by the results. Future studies should investigate whether the incentive salience hypothesis allows for more accurate predictions regarding mesocorticolimbic brain activity of subjects with alcohol dependence and healthy individuals during reward and loss anticipation and further examine the neural substrates underlying a predisposition to dependence.

MRI texture-based radiomics analysis for the identification of altered functional networks in alcoholic patients and animal models

Alcohol use disorder (AUD) is a complex condition representing a leading risk factor for death, disease and disability. Its high prevalence and severe health consequences make necessary a better understanding of the brain network alterations to improve diagnosis and treatment. The purpose of this study was to evaluate the potential of resting-state fMRI 3D texture features as a novel source of biomarkers to identify AUD brain network alterations following a radiomics approach. A longitudinal study was conducted in Marchigian Sardinian alcohol-preferring msP rats (N = 36) who underwent resting-state functional and structural MRI before and after 30 days of alcohol or water consumption. A cross-sectional human study was also conducted among 33 healthy controls and 35 AUD patients. The preprocessed functional data corresponding to control and alcohol conditions were used to perform a probabilistic independent component analysis, identifying seven independent components as resting-state networks. Forty-three radiomic features extracted from each network were compared using a Wilcoxon signed-rank test with Holm correction to identify the network most affected by alcohol consumption. Features extracted from this network were then used in the machine learning process, evaluating two feature selection methods and six predictive models within a nested cross-validation structure. The classification was evaluated by computing the area under the ROC curve. Images were quantized using different numbers of gray-levels to test their influence on the results. The influence of ageing, data preprocessing, and brain iron accumulation were also analyzed. The methodology was validated using structural scans. The striatal network in alcohol-exposed msP rats presented the most significant number of altered features. The radiomics approach supported this result achieving good classification performance in animals (AUC = 0.915 ± 0.100, with 12 features) and humans (AUC = 0.724 ± 0.117, with 9 features) using a random forest model. Using the structural scans, high accuracy was achieved with a multilayer perceptron in both species (animals: AUC > 0.95 with 2 features, humans: AUC > 0.82 with 18 features). The best results were obtained using a feature selection method based on the p-value. The proposed radiomics approach is able to identify AUD patients and alcohol-exposed rats with good accuracy, employing a subset of 3D features extracted from fMRI. Furthermore, it can help identify relevant networks in drug addiction.

Decoding fMRI alcohol cue reactivity and its association with drinking behaviour

BACKGROUND

Cue reactivity, the enhanced sensitivity to conditioned cues, is associated with habitual and compulsive alcohol consumption. However, most previous studies in alcohol use disorder (AUD) compared brain activity between alcohol and neutral conditions, solely as cue-triggered neural reactivity.

OBJECTIVE

This study aims to find the neural subprocesses during the processing of visual alcohol cues in AUD individuals, and how these neural patterns are predictive for relapse.

METHODS

Using cue reactivity and rating tasks, we separately modelled the patterns decoding the processes of visual object recognition and reward appraisal of alcohol cues with representational similarity analysis, and compared the decoding involvements (ie, distance between neural responses and hypothesised decoding models) between AUD and healthy individuals. We further explored connectivity between the identified neural systems and the whole brain and predicted relapse within 6 months using decoding involvements of the neural patterns.

FINDINGS

AUD individuals, compared with healthy individuals, showed higher involvement of motor-related brain regions in decoding visual features, and their reward, habit and executive networks were more engaged in appraising reward values. Connectivity analyses showed the involved neural systems were widely connected with higher cognitive networks during alcohol cue processing in AUD individuals, and decoding involvements of frontal eye fields and dorsolateral prefrontal cortex could contribute to relapse prediction.

CONCLUSIONS

These findings provide insight into how AUD individuals differently decode alcohol cues compared with healthy participants, from the componential processes of visual object recognition and reward appraisal.

CLINICAL IMPLICATIONS

The identified patterns are suggested as biomarkers and potential therapeutic targets in AUD.

Body mass index interacts with sex to predict readmission in in-patients with alcohol use disorder

A previous highly controlled pilot study revealed that body mass index (BMI) predicts outcome of in-patients with alcohol use disorder (AUD) in a sex-specific manner. We here provide translational evidence from a daily clinical routine setting and investigated whether BMI and sex interact to predict 24-month readmission risk in four naturalistic cohorts of a specialized addiction clinic (i.e., all patients admitted to the clinic from 2016 to 2020): (i) in-patients (443 males and 197 females) and (ii) day clinic patients (241 males and 103 females) with a primary diagnosis of AUD; (iii) in-patients (175 males and 98 females) and (iv) day clinic patients (174 males and 64 females) with a primary substance use disorder (SUD) other than alcohol. In the in-patients with AUD, BMI interacted with sex to predict the 24-month readmission risks (p = 0.008; after adjustment for age and liver enzyme activities: p = 0.012); with higher BMI, the risk increases significantly in males, whereas for females, the risk tends to decrease. In the group of overweight in-patients, we found higher readmission rates in males relative to females with an odds ratio of 1.8 (p = 0.038). No such significant effects were found in the other cohorts. This study's findings support previous results, suggesting that the easily accessible BMI may serve as a predictive and sex-sensitive biomarker for outcome in in-patients with AUD. Future studies are necessary to elucidate the underlying aetiopathological mechanisms.

Lack of amygdala habituation to negative emotional faces in alcohol use disorder and the relation to adverse childhood experiences

Aberrant limbic circuit reactivity to negative stimuli might be related to alterations in emotion processing and regulation in alcohol use disorder (AUD). The current study tested for the first time in AUD the hypothesis of aberrant amygdala habituation to repeated aversive stimuli-a robust and reliable neuroimaging marker for emotion processing. We explored the link between deficits in habituation to adverse childhood experience (ACE), a common risk factor for impaired emotion regulation and AUD. AUD individuals (N = 36) and healthy controls (HC; N = 26) participated in an observational case-control functional magnetic resonance imaging (fMRI) study. An established habituation index was used to investigate processing of aversive emotional faces of the amygdala. AUD individuals showed an overall deficit in amygdala habituation (right: t = 4.26, pFWE = 0.004; left: t = 4.79, pFWE ≤ 0.001). Amygdala habituation was significantly related to increased exposure to ACE in HC (t = 3.88, pFWE = 0.012), whereas this association was not observed in AUD individuals (T = 1.80, pFWE = 0.662). Further, a significant association between higher alcohol consumption and reduced amygdala habituation (right: R²  = -0.356, F = 8.736, p = 0.004; left: R²  = -0.309, F = 6.332, p = 0.015) was observed. We found novel evidence for neural alterations in emotion processing in AUD individuals, indexed by deficient amygdala habituation to negative emotional content. We replicated a prior report on a link between ACE and amygdala habituation, a well-established environmental risk factor for mental disorders and emotion dysregulation, in our control sample. Additionally, deficient amygdala habituation related to the amount of alcohol consumption in the overall sample might indicate a short-term substance effect.

Association between iron accumulation in the dorsal striatum and compulsive drinking in alcohol use disorder

RATIONALE

Brain iron accumulation has been observed in neuropsychiatric disorders and shown to be related to neurodegeneration.

OBJECTIVES

In this study, we used quantitative susceptibility mapping (QSM), an emerging MRI technique developed for quantifying tissue magnetic susceptibility, to examine brain iron accumulation in individuals with alcohol use disorder (AUD) and its relation to compulsive drinking.

METHODS

Based on our previous projects, QSM was performed as a secondary analysis with gradient echo sequence images, in 186 individuals with AUD and 274 healthy participants. Whole-brain susceptibility values were calculated with morphology-enabled dipole inversion and referenced to the cerebrospinal fluid. Then, the susceptibility maps were compared between AUD individuals and healthy participants. The relationship between drinking patterns and susceptibility was explored.

RESULTS

Whole-brain analyses showed that the susceptibility in the dorsal striatum (putamen and caudate) among AUD individuals was higher than healthy participants and was positively related to the Obsessive Compulsive Drinking Scale (OCDS) scores and the amount of drinking in the past three months.

CONCLUSIONS

Increased susceptibility suggests higher iron accumulation in the dorsal striatum in AUD. This surrogate for the brain iron level was linearly associated with the compulsive drinking pattern and the recent amount of drinking, which provides us a new clinical perspective in relation to brain iron accumulation, and also might indicate an association of AUD with neuroinflammation as a consequence of brain iron accumulation. The iron accumulation in the striatum is further relevant for functional imaging studies in AUD by potentially producing signal dropout and artefacts in fMRI images.

The impact of COVID-19 pandemic on mental burden and quality of life in physicians: Results of an online survey

Background

In previous pan-/epidemics such as the SARS epidemic of 2002/2003, negative effects on the wellbeing and an increase in symptoms of depression and anxiety were observed in doctors due to social isolation and the threat they experienced. Therefore, it is feared that the COVID-19 pandemic will also have a negative impact on the mental health and quality of life of doctors.

Objective

The impact of the COVID-19 pandemic on the mental health of physicians. In particular, on the subjective anxiety and burden, depression and quality of life for the total sample and subsamples (work in COVID-19 units vs. no work in COVID-19 units).

Materials and methods

In an online survey, 107 physicians (23-42 years) were asked about their mental health during the COVID-19 pandemic. In addition to socio-demographic data, pandemic- and work-related data were also included. For example, infection control measures, deployment on COVID-19 wards and the subjective perceived threat posed by the pandemic. The physicians were asked to rate their perceived anxiety and stress, retrospectively, at 7 different points in time during the pandemic. The Hospital Anxiety and Depression Scale (HADS) was used to retrospectively assess symptoms of anxiety and depression before and after the onset of the pandemic. The quality of life of the participants after 2 years of the pandemic was assessed using the WHO Quality of Life (WHOQOL-BREF).

Results

Both subjective anxiety and burden showed wave-like patterns with higher scores in autumn, winter and spring. We observed significant differences between the seven measurement time points for anxiety [Chi²(6) = 197.05, p < 0.001] as well as for burden [Chi²(6) = 106.33, p < 0.001]. Symptoms of depression and anxiety increased significantly during the COVID-19 pandemic (M = 14.16, SD = 7.83) compared to the pre-pandemic time [M = 7.31, SD = 5.14, t ₍₁₀₆₎ = -10.67, p < 0.001]. Physicians who worked at COVID-19 units showed higher scores in quality of life related to social relationships (M = 70.39, SD = 17.69) than physicians not working at COVID-19 units [M = 61.44, SD = 24.55, t _(90.14) = -2.145, p = 0.035]. The multi-factorial ANOVA showed that previous psychiatric illness (p < 0.001), greater difference in depression scores (p = 0.014), higher anxiety scores (p = 0.048) and less work experience (p = 0.032) led to lower quality of life.

Conclusion

Hospitals should offer specific support, such as supervision, to prevent the development of longer-term psychiatric sequelae likely to lead to sick leave and high costs for the healthcare system.

Trial registration

The study has been registered at the German Clinical Trials Registry (DRKS-ID: DRKS00028984).

Does the Augmentation of Trauma Informed Hatha Yoga Increase the Effect of Dialectical Behavior Therapy for Substance Use Disorders on Psychopathological Strain of Patients with Borderline Personality Disorder and Comorbid Substance Use Disorder? Results of a Quasi-Experimental Study

BACKGROUND

Borderline personality disorder (BPD) is one of the most common personality disorders among persons with substance use disorders (SUDs) and is characterized by severe clinical symptoms. The aim of this study was to investigate if the effect of dialectical behavior therapy for substance use disorders (DBT-S) inpatient treatment on psychopathological symptom load in patients suffering from both BPD and SUD can be augmented by weekly 60-min "Trauma Informed Hatha Yoga" sessions.

MATERIALS AND METHODS

Thirty-nine patients suffering from comorbid BPD and SUD were consecutively in time included in this quasi-experimental pilot study (first intervention then control group). In the intervention group, weekly Trauma Informed Hatha Yoga sessions were added to standard DBT-S for 8 weeks. The participants of the control group received standard DBT-S. All participants completed several self-report questionnaires to assess symptoms of depression, anxiety, symptoms of BPD, and their subjective stress perception at three points in time during the study course.

RESULTS

A repeated measures analysis of variance with patients' psychopharmacological medication as covariate revealed a significant main effect of time for each of the psychometric scales (State and Trait Anxiety Inventory subscale for state anxiety [STAI-S] p = 0.001, Beck Depression Inventory [BDI] p < 0.001; Borderline Symptom List 23 [BSL] p = 0.036) indicating that the psychopathological symptom load of the patients was significantly lower at the end of the DBT-S therapy compared to the beginning in both study groups. Moreover, there was a significant interaction effect of group*time on the psychometric scales STAI-T (subscale for trait anxiety) sum score (p = 0.010) and the sum score of the Perceived Stress Scale (PSS) (p = 0.043). This was expressed by the fact that the participants of the intervention group showed a significant reduction of the STAI-T sum score as well as the sum score of the Perceived Stress Scale (PSS), while the control group did not. Due to the exploratory nature of this study, correction for multiple testing was omitted.

CONCLUSION

Although they are very preliminary, our results suggest that practicing Trauma Informed Hatha Yoga on a regular basis in addition to DBT-S inpatient treatment seems to reduce the level of trait anxiety and perceived stress significantly more than DBT-S inpatient treatment alone. Nevertheless, the effectiveness of Trauma Informed Hatha Yoga in reducing trait anxiety and perceived stress in patients suffering from SUD und BPD must be tested in large randomized controlled trials.

The Role of Unawareness, Volition, and Neural Hyperconnectivity in Alcohol Use Disorder: A Functional Magnetic Resonance Imaging Study

BACKGROUND

Automated alcohol craving and habitual alcohol consumption characterize the later stages of alcohol use disorder (AUD). This study reanalyzed previously collected functional neuroimaging data in combination with the Craving Automated Scale for Alcohol (CAS-A) questionnaire to investigate the neural correlates and brain networks underlying automated drinking characterized by unawareness and nonvolition.

METHODS

We assessed 49 abstinent male patients with AUD and 36 male healthy control participants during a functional magnetic resonance imaging-based alcohol cue-reactivity task. We performed whole-brain analyses examining the associations between CAS-A scores and other clinical instruments and neural activation patterns in the alcohol versus neutral contrast. Furthermore, we performed psychophysiological interaction analyses to assess the functional connectivity between predefined seed regions and other brain areas.

RESULTS

In patients with AUD, higher CAS-A scores correlated with greater activation in dorsal striatal, pallidal, and prefrontal regions, including frontal white matter, and with lower activation in visual and motor processing regions. Between-group psychophysiological interaction analyses showed extensive connectivity between the seed regions inferior frontal gyrus and angular gyrus and several frontal, parietal, and temporal brain regions in AUD versus healthy control participants.

CONCLUSIONS

The present study applied a new lens to previously acquired alcohol cue-reactivity functional magnetic resonance imaging data by correlating neural activation patterns with clinical CAS-A scores to elucidate potential neural correlates of automated alcohol craving and habitual alcohol consumption. Our results support previous findings showing that alcohol addiction is associated with hyperactivation in habit-processing regions, with hypoactivation in areas mediating motor and attention processing, and with general hyperconnectivity.

Neural cue reactivity is not stronger in male than in female patients with alcohol use disorder

Background

Males consume more alcohol than females, and alcohol use disorder (AUD) is more prevalent in males than females. However, females progress faster to AUD. Sex differences in neural alcohol cue reactivity were previously observed in young social drinkers, indicating a role of hypersensitivity to alcohol-related cues in very early stages of addiction. To our knowledge, this is the first study on patients diagnosed with AUD to test sex differences in neural reactivity to alcohol cues in order to widen previous findings.

Methods

We analyzed data from previous studies, using a well-established functional magnetic resonance imaging (fMRI) paradigm to compare neural reactivity to alcohol cues between 42 female and 124 male patients with AUD (mean age 45 and 46 years) in predefined regions of interest that were implicated by previous studies (ventral and dorsal striatum as well as caudate, putamen, amygdala, hippocampus, insula, anterior cingulate cortex, and medial prefrontal cortex) using independent samples t-tests. Post-hoc, effect size calculations were performed.

Results

Throughout all nine regions of interest, we found no statistically significant sex differences in neural reactivity toward alcoholic pictures alone or in comparison to neutral pictures (p &gt; 0.05, FDR-corrected). Post-hoc effect size estimates indicated a magnitude between 0.137 and 0.418 (Hedge’s g) on alcohol reactivity to alcohol cues compared to neutral cues and indicate very small to less than medium effect sizes in the direction of higher cue reactivity in female patients.

Conclusion

Previous studies showed sex differences in neural alcohol cue reactivity in younger social and problematic alcohol drinkers, i.e., stronger striatal cue-reactivity in males. After correction for multiple comparisons, we did not observe significant sex differences in a cohort of middle-aged females and males with AUD. Sex differences that are present during early phases of addiction development might disappear at later stages of AUD and might thus be considered as clinically less relevant in patients with more severe AUD.

The clinical course of comorbid substance use disorder and attention deficit/hyperactivity disorder: protocol and clinical characteristics of the INCAS study

BACKGROUND

Substance use disorders (SUD) often co-occur with attention deficit hyperactivity disorder (ADHD). Although the short-term effects of some specific interventions have been investigated in randomized clinical trials, little is known about the long-term clinical course of treatment-seeking SUD patients with comorbid ADHD.

AIMS

This paper presents the protocol and baseline clinical characteristics of the International Naturalistic Cohort Study of ADHD and SUD (INCAS) designed and conducted by the International Collaboration on ADHD and Substance Abuse (ICASA) foundation. The overall aim of INCAS is to investigate the treatment modalities provided to treatment-seeking SUD patients with comorbid ADHD, and to describe the clinical course and identify predictors for treatment outcomes. This ongoing study employs a multicentre observational prospective cohort design. Treatment-seeking adult SUD patients with comorbid ADHD are recruited, at 12 study sites in nine different countries. During the follow-up period of nine months, data is collected through patient files, interviews, and self-rating scales, targeting a broad range of cognitive and clinical symptom domains, at baseline, four weeks, three months and nine months.

RESULTS

A clinically representative sample of 578 patients (137 females, 441 males) was enrolled during the recruitment period (June 2017-May 2021). At baseline, the sample had a mean age (SD) of 36.7 years (11.0); 47.5% were inpatients and 52.5% outpatients; The most prevalent SUDs were with alcohol 54.2%, stimulants 43.6%, cannabis 33.1%, and opioids 14.5%. Patients reported previous treatments for SUD in 71.1% and for ADHD in 56.9%. Other comorbid mental disorders were present in 61.4% of the sample: major depression 31.5%, post-traumatic stress disorder 12.1%, borderline personality disorder 10.2%.

CONCLUSIONS

The first baseline results of this international cohort study speak to its feasibility. Data show that many SUD patients with comorbid ADHD had never received treatment for their ADHD prior to enrolment in the study. Future reports on this study will identify the course and potential predictors for successful pharmaceutical and psychological treatment outcomes.

TRIAL REGISTRATION

ISRCTN15998989 20/12/2019.

Elevated Oxytocin Receptor Blood Concentrations Predict Higher Risk for, More, and Earlier 24-Month Hospital Readmissions after In-Patient Detoxification in Males with Alcohol Use Disorder

Alcohol use disorder (AUD) is a major global mental health challenge. Knowledge concerning mechanisms underlying AUD and predictive biomarkers of AUD progression and relapse are insufficient. Recently, addiction research is focusing attention on the oxytocin system. However, to our knowledge, blood concentrations of the oxytocin receptor (OXTR) have not yet been studied in AUD. Here, in sex-separated analyses, OXTR serum concentrations were compared between early-abstinent in-patients with AUD (113 men, 87 women) and age-matched healthy controls (133 men, 107 women). The OXTR concentrations were correlated with sex hormone and oxytocin concentrations and alcohol-related hospital readmissions during a 24-month follow-up. In male patients with AUD, higher OXTR concentrations were found in those with an alcohol-related readmission than in those without (143%; p = 0.004), and they correlated with more prospective readmissions (ρ = 0.249; p = 0.008) and fewer days to the first readmission (ρ = −0.268; p = 0.004). In men and women, OXTR concentrations did not significantly differ between patients with AUD and controls. We found lower OXTR concentrations in smokers versus non-smokers in female patients (61%; p = 0.001) and controls (51%; p = 0.003). In controls, OXTR concentrations correlated with dihydrotestosterone (men, ρ = 0.189; p = 0.030) and testosterone concentrations (women, ρ = 0.281; p = 0.003). This clinical study provides novel insight into the role of serum OXTR levels in AUD. Future studies are encouraged to add to the available knowledge and investigate clinical implications of OXTR blood concentrations.

G-CuP: the effect of a forced oral glucose intake on alcohol craving and mesolimbic cue reactivity in alcohol dependence-study protocol of a randomized, double-blind, placebo-controlled crossover study

BACKGROUND

Multiple studies indicate that a lower plasma level of the acetylated form of the appetite-regulating hormone ghrelin and higher plasma levels of insulin lead to a reduction in subjective alcohol craving and a reduced mesolimbic cue reactivity in functional magnetic resonance imaging (fMRI) when being exposed to alcohol-associated stimuli. The ghrelin level can physiologically be reduced by the induction of stomach distension and the ingestion of glucose or lipids.

METHODS

A total of 108 alcohol-dependent patients aged between 18 and 65 years are examined in the randomized, double-blind, placebo-controlled crossover study. After collecting demographic and psychometric data, participants take part in an alcohol exposure session. Afterwards, the participants go through the intervention condition (oral glucose intake) and the control condition (placebo intake) in a randomized order on two examination days. Blood samples are taken repeatedly (every 10 min) during the study course on both measuring days to determine changes in acetylated and total ghrelin and insulin plasma levels. In parallel, subjective alcohol craving after the glucose or placebo intake as the primary outcome is assessed using the Alcohol Urge Questionnaire (AUQ) and a visual analog scale (VAS). To examine the mesolimbic cue reactivity as the secondary outcome, a fMRI measurement is conducted while being exposed to alcohol-related stimuli. Appropriate statistical analysis will be used for the evaluation of the outcomes.

DISCUSSION

If successful, the results of this study could offer alcohol-dependent patients a new potential option for acute short-term reduction of alcohol craving and thus prevent relapses and prolong periods of abstinence in the long term.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00022419 (UTN: U1111-1278-9428). Retrospectively registered on September 15, 2020.

Vulnerability for alcohol use disorder after adverse childhood experiences (AUDACE): protocol for a longitudinal fMRI study assessing neuropsychobiological risk factors for relapse

BACKGROUND

Adverse childhood experiences (ACE) are common and may predispose affected individuals to various health problems, including alcohol use disorder (AUD). Although a relationship between ACE and AUD has been well-established, potential mechanisms that may underlie this relationship remain to be elucidated. The importance of these mechanisms with respect to relapse risk is of particular interest, given the clinical relevance of relapse in addictions. Thus, the aim of this study is to longitudinally assess the role of clinically relevant variables in the relationship between ACE and AUD, namely stress sensitivity, emotion processing, cue reactivity and cognitive functioning (response inhibition and working memory), in relation to relapse risk.

METHODS AND ANALYSIS

In this observational, longitudinal case-control study, 36 patients with AUD and heavy drinkers with varying degrees of ACE from a previous project (NCT03758053) as well as newly recruited participants from the same study population will be assessed. Besides measuring long-term relapse in AUD by re-examining these 36 previous participants after 2-2.5 years, factors contributing to short-term relapse will be examined by reassessing all participants on a 3-month follow-up. Furthermore, participants with no or mild ACE will be compared with participants with moderate to severe ACE to assess between-subject differences in risk factors for AUD. Questionnaires and interviews will thus be used to cover individuals' drinking behaviour and ACE. Emotion processing, stress sensitivity, cue reactivity and cognitive functioning will be assessed using task-based functional MRI (fMRI). Additionally, saliva cortisol and blood samples will be taken to measure hormonal stress response and to perform genome wide association analyses, respectively. The general linear model will be applied on the first level fMRI analyses, whereas for the second level analyses and analyses of behavioural data, t-tests, regression analyses, repeated-measures and one-way analysis of variances will be used.

ETHICS AND DISSEMINATION

This study has been approved by the ethics committee of the Medical Faculty Mannheim of Heidelberg University (ethics approval number: 2018-560N-MA with amendment from 29 June 2021). The findings of this study will be presented at conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05048758; Pre-results, clinicaltrials.gov.

Alcohol dependence decreases functional activation of the caudate nucleus during model-based decision processes

BACKGROUND

Impaired decision making, a key characteristic of alcohol dependence (AD), manifests in continuous alcohol consumption despite severe negative consequences. The neural basis of this impairment in individuals with AD and differences with known neural decision mechanisms among healthy subjects are not fully understood. In particular, it is unclear whether the choice behavior among individuals with AD is based on a general impairment of decision mechanisms or is mainly explained by altered value attribution, with an overly high subjective value attributed to alcohol-related stimuli.

METHODS

Here, we use a functional magnetic resonance imaging (fMRI) monetary reward task to compare the neural processes of model-based decision making and value computation between AD individuals (n = 32) and healthy controls (n = 32). During fMRI, participants evaluated monetary offers with respect to dynamically changing constraints and different levels of uncertainty.

RESULTS

Individuals with AD showed lower activation associated with model-based decision processes in the caudate nucleus than controls, but there were no group differences in value-related neural activity or task performance.

CONCLUSIONS

Our findings highlight the role of the caudate nucleus in impaired model-based decisions of alcohol-dependent individuals.

German Guidelines on Screening, Diagnosis, and Treatment of Alcohol Use Disorders: Update 2021

INTRODUCTION

Alcohol consumption in Germany is associated with considerable health and economic consequences. In addition to prevention, the early detection and differential treatment of those affected play an important role. The guideline "Screening, Diagnosis, and Treatment of Alcohol Use Disorders" forms the basis of this care for people suffering from alcohol use disorders. Regular updates integrate the current state of research evidence and clinical expertise.

METHODS

Under the auspices of the German Society for Psychiatry, Psychotherapy, Psychosomatics, and Neurology and the German Society for Addiction Research and Addiction Therapy e.V. (DG-Sucht), the 2019-2020 S3 guideline on alcohol was revised by eight working groups. Thirty-five professional societies participated in a structured consensus process to deliberate the recommendations. Potential conflicts of interest were examined in advance, documented, and taken into account during the voting on the recommendations.

RESULTS

The guideline provides recommendations on screening and brief interventions for different groups of people, as well as on treatment of individuals in the acute and post-acute phases of withdrawal. Special emphasis was placed on the treatment of comorbid somatic and psychological disorders. In addition, recommendations for specific groups of people (e.g., children and adolescents, pregnant women) have been made and adapted to the German care landscape.

ON-ICE trial: Investigation of the combined effects of oxytocin and naltrexone on stress-induced and alcohol cue-induced craving in alcohol use disorder-Study protocol of a phase II randomised double-blind placebo-controlled parallel-group trial

INTRODUCTION

Although alcohol dependence (AD) is highly prevalent, only few medications are approved for its treatment. While currently approved medications, such as naltrexone (NTX), reduce craving and relapse risk to a certain extent, new approaches are needed to complement these pharmaca. One potential compound is oxytocin (OXY), which proved beneficial effects on alcohol craving and stress reactivity in preliminary clinical studies and synergism with NTX effects.

METHODS AND ANALYSIS

This clinical phase II trial is a monocentre two-armed, placebo (PLC)-controlled, 1:1 randomised, double-blind, parallel-group study. 62 participants with AD will be randomised to receive either intranasal OXY spray (24 IU) or PLC spray plus oral NTX (50 mg) for 2 days, and alcohol craving will be assessed using a validated combined stress-exposure and cue-exposure experiments and MRI. The primary outcome will be the intensity of alcohol craving, assessed using the Alcohol Urge Questionnaire (AUQ), 60 min after OXY/PLC application, directly after the stress and cue exposures. Secondary outcomes include subjective stress, negative affect, cortisol and OXY plasma levels, and neural response to alcohol and emotional cues and natural rewards. Follow-up drinking data were collected over 90 days. The primary efficacy analysis will test the difference between the verum and the PLC group in the distribution of AUQ craving scores. Appropriate statistical analysis will be used for the evaluation of the secondary outcomes.

ETHICS AND DISSEMINATION

This trial has been approved by the ethics committee of Heidelberg University and competent authority. All participants in the trial will provide written informed consent. The study will be conducted according to the principles of the Declaration of Helsinki and in accordance to the German Medicinal Products act. Results of this study will be disseminated in peer-reviewed scientific journals and deidentified data, and the statistical analysis plan will be made available via open-access online repositories.

TRIAL REGISTRATION NUMBERS

EudraCT 2021-003610-40 and NCT05093296.

A methodological checklist for fMRI drug cue reactivity studies: development and expert consensus

Cue reactivity is one of the most frequently used paradigms in functional magnetic resonance imaging (fMRI) studies of substance use disorders (SUDs). Although there have been promising results elucidating the neurocognitive mechanisms of SUDs and SUD treatments, the interpretability and reproducibility of these studies is limited by incomplete reporting of participants' characteristics, task design, craving assessment, scanning preparation and analysis decisions in fMRI drug cue reactivity (FDCR) experiments. This hampers clinical translation, not least because systematic review and meta-analysis of published work are difficult. This consensus paper and Delphi study aims to outline the important methodological aspects of FDCR research, present structured recommendations for more comprehensive methods reporting and review the FDCR literature to assess the reporting of items that are deemed important. Forty-five FDCR scientists from around the world participated in this study. First, an initial checklist of items deemed important in FDCR studies was developed by several members of the Enhanced NeuroImaging Genetics through Meta-Analyses (ENIGMA) Addiction working group on the basis of a systematic review. Using a modified Delphi consensus method, all experts were asked to comment on, revise or add items to the initial checklist, and then to rate the importance of each item in subsequent rounds. The reporting status of the items in the final checklist was investigated in 108 recently published FDCR studies identified through a systematic review. By the final round, 38 items reached the consensus threshold and were classified under seven major categories: 'Participants' Characteristics', 'General fMRI Information', 'General Task Information', 'Cue Information', 'Craving Assessment Inside Scanner', 'Craving Assessment Outside Scanner' and 'Pre- and Post-Scanning Considerations'. The review of the 108 FDCR papers revealed significant gaps in the reporting of the items considered important by the experts. For instance, whereas items in the 'General fMRI Information' category were reported in 90.5% of the reviewed papers, items in the 'Pre- and Post-Scanning Considerations' category were reported by only 44.7% of reviewed FDCR studies. Considering the notable and sometimes unexpected gaps in the reporting of items deemed to be important by experts in any FDCR study, the protocols could benefit from the adoption of reporting standards. This checklist, a living document to be updated as the field and its methods advance, can help improve experimental design, reporting and the widespread understanding of the FDCR protocols. This checklist can also provide a sample for developing consensus statements for protocols in other areas of task-based fMRI.

The effects of nalmefene on the impulsive and reflective system in alcohol use disorder: A resting-state fMRI study

RATIONALE

Central aspects of alcohol use disorder (AUD) are the irresistible desire for alcohol and impaired control over its intake. According to the triadic neurocognitive model of addiction, this arises from aberrant functioning of different neural and cognitive systems: an impulsive system, a reflective system, and the abnormal dynamics between both systems based on an insular-dependent system.

OBJECTIVES

In this study, we examined the effects of a single dose of nalmefene on resting-state functional connectivity (rsFC) patterns within and between these addiction-related neural systems in AUD.

METHODS

Non-treatment seeking participants with AUD (N = 17; 19-66 years, 6 female) took part in a randomized, placebo-controlled, double-blind, crossover study and received either a single dose of 18 mg nalmefene or a placebo. Using seed-based correlation analyses on resting-state functional magnetic resonance imaging data, we examined the effects of nalmefene on key nodes related to the (1) impulsive system; (2) reflective system; (3) salience network; and (4) default mode network.

RESULTS

Under nalmefene, participants showed reduced rsFC between components of the impulsive system (Nucleus accumbens-putamen/pallidum/insula). Reduced rsFC was found between elements of the reflective system and impulsive system (orbitofrontal cortex-insula/putamen/pallidum), salience network (orbitofrontal cortex-insula/inferior frontal gyrus), and default mode network (lateral prefrontal cortex-precuneus/cuneus). Components of the salience network showed both increased (anterior cingulate cortex) and decreased (insular cortex) rsFC to elements of the reflective system.

CONCLUSION

A single dose of nalmefene impacts rsFC and alters the interaction between key nodes of addiction-related neural systems in non-treatment seeking participants with AUD. Nalmefene may normalize rsFC patterns by weakening the impulsive system while strengthening the reflective system.

TRIAL REGISTRATION

clinicaltrials.gov: NCT02372318.

A History of Childhood Maltreatment Has Substance- and Sex-Specific Effects on Craving During Treatment for Substance Use Disorders

RATIONALE

Childhood maltreatment (CM) leads to detrimental mental health outcomes, such as substance use disorders (SUD). This study examined prevalence and severity of all five types of CM with respect to specific substances and sex in treatment-seeking individuals with SUD. The influences of type of CM and symptoms of depressiveness, anxiety, and perceived stress on substance craving at admission as well as craving reduction during SUD treatment were examined.

METHODS

N = 546 patients in treatment for SUD and N = 109 individuals in opioid maintenance treatment filled out questionnaires regarding CM (Childhood Trauma Questionnaire) and psychopathologies. Substance craving was assessed throughout treatment using the Mannheim Craving Scale. Group differences in CM, type of substance and sex were examined. General linear models were applied to examine influences on substance craving.

RESULTS

Higher prevalence and severity of all five subtypes of CM were observed in individuals with SUD compared to the general population. Women were more severely affected by emotional and sexual abuse than men. Patients with cannabis use disorder reported more severe experiences of emotional abuse compared to all other substances. Craving at admission to treatment was influenced by emotional abuse, however, symptoms of depressiveness, anxiety, and perceived stress contributed to craving at admission or craving reduction during treatment.

CONCLUSION

CM relates to SUD and should be incorporated in prevention and treatment of SUD. Underlying mechanisms of the association might relate to impairments in processing and regulation of stress, emotions, and interpersonal relations following a history of CM.

Plasma calcium concentration during detoxification predicts neural cue-reactivity and craving during early abstinence in alcohol-dependent patients

Recent studies on the pathophysiology of alcohol dependence suggest a link between peripheral calcium concentrations and alcohol craving. Here, we investigated the association between plasma calcium concentration, cue-induced brain activation, and alcohol craving. Plasma calcium concentrations were measured at the onset of inpatient detoxification in a sample of N = 115 alcohol-dependent patients. Alcohol cue-reactivity was assessed during early abstinence (mean 11.1 days) using a functional magnetic resonance imaging (fMRI) alcohol cue-reactivity task. Multiple regression analyses and bivariate correlations between plasma calcium concentrations, clinical craving measures and neural alcohol cue-reactivity (CR) were tested. Results show a significant negative correlation between plasma calcium concentrations and compulsive alcohol craving. Higher calcium levels predicted higher alcohol cue-induced brain response in a cluster of frontal brain areas, including the dorsolateral prefrontal cortex (dlPFC), the anterior prefrontal cortex (alPFC), and the inferior (IFG) and middle frontal gyri (MFG). In addition, functional brain activation in those areas correlated negatively with craving for alcohol during fMRI. Higher peripheral calcium concentrations during withdrawal predicted increased alcohol cue-induced brain activation in frontal brain areas, which are associated with craving inhibition and cognitive control functions. This might indicate that higher plasma calcium concentrations at onset of detoxification could modulate craving inhibition during early abstinence.Trial registration number: DRKS00003388; date of registration: 14.12.2011.

S3 Guideline "Smoking and Tobacco Dependence: Screening, Diagnosis, and Treatment" - Short Version

INTRODUCTION

In addition to the prevention of tobacco consumption, the establishment and assurance of high-quality treatment for harmful use and dependence on tobacco products remains an important health-related task in Germany. Regular updating of the Association of the Scientific Medical Societies (AWMF) S3 guideline "Smoking and Tobacco Dependence: Screening, Diagnosis, and Treatment" (Tobacco Guideline) offers a sustainable and reputable source of knowledge on smoking cessation.

METHODS

Under the auspices of the German Society for Psychiatry, Psychotherapy, Psychosomatics, and Neurology (DGPPN) and the German Society for Addiction Research and Addiction Therapy (DG-Sucht), the Tobacco Guideline was revised in 2019-2020 by 63 experts, who were involved in the development process of the text, in 11 working groups. Undue influence of conflicts of interest on the guideline could be minimized through careful conflict of interest management. Delegates from 50 professional societies discussed the 80 guideline recommendations and voted online.

RESULTS

In addition to recommendations for screening and diagnostics, the Tobacco Guideline takes a positive stance towards the use of low-threshold counseling and support services. If, due to the severity of the tobacco-related disorder, brief counseling, telephone counseling, or internet- or smartphone-based methods are not sufficiently effective, individual or group behavioral therapy, possibly in combination with medication, is indicated. If nicotine replacement therapy is not effective, varenicline or bupropion should be offered. Alternative strategies with a lower level of recommendation are hypnotherapy, mindfulness-based treatments, or medication with cytisine. In adolescents and pregnant women, the use of medication should be limited to well-specified exceptions and nicotine replacement. The mean agreement with the recommendations reached a value of 98%. A general overview of the treatment recommendations of the Tobacco Guideline is provided by three clinical algorithms.

A Smarter Way to Use Your Smartphone: An Intervention to Limit Smartphone-Related Distractions Reduces Hyperactivity but Not Inattention Symptoms

INTRODUCTION

Smartphones are often helpful in our everyday lives. Yet, they also tend to interrupt us during other activities. It has been argued that such distractions contribute to attention-deficit/hyperactivity disorder-like symptoms. However, since there are mostly correlational studies, the causal nature of this relationship is unclear. Our aim was to test whether reducing smartphone-related distractions might have a beneficial effect on inattention and hyperactive symptoms.

METHODS

We conducted a 1-week field experiment with 37 healthy undergraduates and quasi-randomly assigned them to an intervention or control group (CG). The intervention group was given theory-based specific instructions that aimed at reducing smartphone-related distractions, whereas the CG received no intervention. The outcomes of interest were inattention level, hyperactive symptoms, and working memory accuracy.

RESULTS

Compared to those in the control condition, participants who limited their smartphone use showed considerable reductions in hyperactive symptoms after 1 week - particularly those who displayed high problematic smartphone use. However, there were no group differences regarding inattention symptoms and working memory accuracy.

DISCUSSION

The results give a first hint that strategically reducing smartphone-related distractions via specific but simple use modifications can mitigate hyperactive symptoms. Especially people with problematic smartphone use seem to profit from such an intervention. Remaining questions and directions are discussed.

Reliability of the fMRI-based assessment of self-evaluation in individuals with internet gaming disorder

The self-concept-defined as the cognitive representation of beliefs about oneself-determines how individuals view themselves, others, and their actions. A negative self-concept can drive gaming use and internet gaming disorder (IGD). The assessment of the neural correlates of self-evaluation gained popularity to assess the self-concept in individuals with IGD. This attempt, however, seems to critically depend on the reliability of the investigated task-fMRI brain activation. As first study to date, we assessed test-retest reliability of an fMRI self-evaluation task. Test-retest reliability of neural brain activation between two separate fMRI sessions (approximately 12 months apart) was investigated in N = 29 healthy participants and N = 11 individuals with pathological internet gaming. We computed reliability estimates for the different task contrasts (self, a familiar, and an unknown person) and the contrast (self > familiar and unknown person). Data indicated good test-retest reliability of brain activation, captured by the "self", "familiar person", and "unknown person" contrasts, in a large network of brain regions in the whole sample (N = 40) and when considering both experimental groups separately. In contrast to that, only a small set of brain regions showed moderate to good reliability, when investigating the contrasts ("self > familiar and unknown person"). The lower reliability of the contrast can be attributed to the fact that the constituting contrast conditions were highly correlated. Future research on self-evaluation should be cautioned by the findings of substantial local reliability differences across the brain and employ methods to overcome these limitations.

Test-retest reliability of neural alcohol cue-reactivity: Is there light at the end of the magnetic resonance imaging tube?

Over the last decades, the assessment of alcohol cue-reactivity gained popularity in addiction research, and efforts were undertaken to establish neural biomarkers. This attempt however depends on the reliability of cue-induced brain activation. Thus, we assessed test-retest reliability of alcohol cue-reactivity and its implications for imaging studies in addiction. We investigated test-retest reliability of alcohol cue-induced brain activation in 144 alcohol-dependent patients over 2 weeks. We computed established reliability estimates, such as intraclass correlation (ICC), Dice and Jaccard coefficients, for the three contrast conditions of interest: 'alcohol', 'neutral' and the 'alcohol versus neutral' difference contrast. We also investigated how test-retest reliability of the different contrasts affected the capacity to establishing associations with clinical data and determining effect size estimates. Whereas brain activation, indexed by the constituting contrast conditions 'alcohol' and 'neutral' separately, displayed overall moderate (ICC > 0.4) to good (ICC > 0.75) test-retest reliability in areas of the mesocorticolimbic system, the difference contrast 'alcohol versus neutral' showed poor overall reliability (ICC < 0.40), which was related to the intercorrelation between the constituting conditions. Data simulations and analyses of craving data confirmed that the low reliability of the difference contrast substantially limited the capacity to establish associations with clinical data and precisely estimate effect sizes. Future research on alcohol cue-reactivity should be cautioned by the low reliability of the common 'alcohol versus neutral' difference contrast. We propose that this limitation can be overcome by using the constituent task conditions as an individual difference measure, when intending to longitudinally monitor brain responses.

Increased network centrality of the anterior insula in early abstinence from alcohol

Abnormal resting‐state functional connectivity, as measured by functional magnetic resonance imaging (MRI), has been reported in alcohol use disorders (AUD), but findings are so far inconsistent. Here, we exploited recent developments in graph‐theoretical analyses, enabling improved resolution and fine‐grained representation of brain networks, to investigate functional connectivity in 35 recently detoxified alcohol dependent patients versus 34 healthy controls. Specifically, we focused on the modular organization, that is, the presence of tightly connected substructures within a network, and on the identification of brain regions responsible for network integration using an unbiased approach based on a large‐scale network composed of more than 600 a priori defined nodes. We found significant reductions in global connectivity and region‐specific disruption in the network topology in patients compared with controls. Specifically, the basal brain and the insular–supramarginal cortices, which form tightly coupled modules in healthy subjects, were fragmented in patients. Further, patients showed a strong increase in the centrality of the anterior insula, which exhibited stronger connectivity to distal cortical regions and weaker connectivity to the posterior insula. Anterior insula centrality, a measure of the integrative role of a region, was significantly associated with increased risk of relapse. Exploratory analysis suggests partial recovery of modular structure and insular connectivity in patients after 2 weeks. These findings support the hypothesis that, at least during the early stages of abstinence, the anterior insula may drive exaggerated integration of interoceptive states in AUD patients with possible consequences for decision making and emotional states and that functional connectivity is dynamically changing during treatment.

Assessment of automated craving across substances and across cultures: stability-analysis of the Craving Automated Scale (CAS)

BACKGROUND

The transition from hedonic to compulsive use in Substance Use Disorders (SUD) is a critical point in SUD progression and hence relevant for assessment and treatment. To measure the habitual patterns of substance consumption, the Craving Automated Scales (CAS) for alcohol (CAS-A), substances (CAS-S) and cigarette smoking (CAS-CS) were developed and introduced to different countries. In this study, we aimed to investigate the structural stability of CAS across substances and cultures.

METHODS

This study analyzed the CAS-scores of a sample of 370 participants in Germany, China and the UK, including 262 opioid-users, 65 smokers and 43 alcohol-users. We performed stability analyses to check the stability (i. e. factorial invariance) of factor solutions. Based on confirmed stability of the general factor (gfactor) solution and the calculations rule obtained in the previous validation of CAS-alcohol (CAS-A), the factor structures of CAS-A, CAS-S and CAS-CS were compared.

RESULTS

The gfactor solutions based on calculations rule shows good stability, with the mean stability coefficients of 0.990 and 0.977 for CAS-S and CAS-CS respectively. The gfactor patterns were similar for CAS-A, CAS-S and CAS-CS, as well as across samples (Germany, China and the UK), with most factor-loadings larger than 0.7. Based on these findings, CAS-S and CAS-CS were also associated with established clinical measures of SUD.

CONCLUSIONS

Our findings suggest the two-gfactor solution based on a proposed calculation rule has a high stability across substances and cultures. This could be in line with common neurobiological mechanisms underlying habitual substance use. Moreover, comparing CAS with established clinical tools suggests that CAS might assess the automated behavior in substance consumption in a more sophisticated way.

Association Between Functional and Structural Brain Connectivity of the Default Mode Network in Non-treatment Seeking Individuals With Alcohol Use Disorder

AIMS

Alcohol use disorder (AUD) is associated with alterations within the default mode network (DMN) at rest. Also, impaired white matter structures have been observed in individuals with AUD. This study developed a workflow for examining the relation between functional and structural connectivity, exemplary for nodes of the DMN within a sample of non-treatment seeking individuals with AUD. Furthermore, AUD severity was correlated with both measures independently.

METHODS

The functional magnetic resonance imaging (fMRI) protocol included anatomical, resting state and diffusion weighted imaging measurements. Independent component analyses and deterministic fiber tracking as well as correlation analyses, including the severity of AUD, were performed. N = 18 out of 23 adult study participants took part in the fMRI examination, and N = 15 were included in the final analyses.

RESULTS

Established resting-state networks were reliably identified in our sample. Structural connections were found between several nodes of the DMN, whereas only fibers between the medial prefrontal cortex and the posterior cingulate cortex were reliably detected in all individuals. A negative correlation was observed between brain activation during rest and AUD severity in left parietal and temporal regions and the putamen. A more severe AUD predicted impairments in white matter integrity of the cingulum.

CONCLUSION

In AUD, information obtained from a combination of resting-state, diffusion weighted data and clinical information has great potential to provide a more profound understanding of the disorder since alterations may already become apparent at earlier stages of the disorder, e.g. in non-treatment seeking individuals.

SUMMARY

Alcohol use disorder leads to alterations in the default mode network of the resting brain that is associated with the severity of the disorder. Following our workflow, white matter impairments can be observed between some of the nodes of the default mode network using diffusion tensor imaging. Both, resting-state functional and structural connectivity relate to the severity of alcohol use disorder.

Genetic contributions to alcohol use disorder treatment outcomes: a genome-wide pharmacogenomics study

Naltrexone can aid in reducing alcohol consumption, while acamprosate supports abstinence; however, not all patients with alcohol use disorder (AUD) benefit from these treatments. Here we present the first genome-wide association study of AUD treatment outcomes based on data from the COMBINE and PREDICT studies of acamprosate and naltrexone, and the Mayo Clinic CITA study of acamprosate. Primary analyses focused on treatment outcomes regardless of pharmacological intervention and were followed by drug-stratified analyses to identify treatment-specific pharmacogenomic predictors of acamprosate and naltrexone response. Treatment outcomes were defined as: (1) time until relapse to any drinking (TR) and (2) time until relapse to heavy drinking (THR; ≥ 5 drinks for men, ≥4 drinks for women in a day), during the first 3 months of treatment. Analyses were performed within each dataset, followed by meta-analysis across the studies (N = 1083 European ancestry participants). Single nucleotide polymorphisms (SNPs) in the BRE gene were associated with THR (min p = 1.6E-8) in the entire sample, while two intergenic SNPs were associated with medication-specific outcomes (naltrexone THR: rs12749274, p = 3.9E-8; acamprosate TR: rs77583603, p = 3.1E-9). The top association signal for TR (p = 7.7E-8) and second strongest signal in the THR (p = 6.1E-8) analysis of naltrexone-treated patients maps to PTPRD, a gene previously implicated in addiction phenotypes in human and animal studies. Leave-one-out polygenic risk score analyses showed significant associations with TR (p = 3.7E-4) and THR (p = 2.6E-4). This study provides the first evidence of a polygenic effect on AUD treatment response, and identifies genetic variants associated with potentially medication-specific effects on AUD treatment response.

Characterization and quantification of alcohol-related polyneuropathy by magnetic resonance neurography

BACKGROUND

We characterized and quantified peripheral nerve damage in alcohol-dependent patients (ADP) by magnetic resonance neurography (MRN) in correlation with clinical and electrophysiologic findings.

METHODS

Thirty-one adult patients with a history of excessive alcohol consumption and age-/sex-matched healthy controls were prospectively examined. After detailed neurologic and electrophysiologic testing, the patient group was subdivided into ADP with alcohol-related polyneuropathy (ALN) and without ALN (Non-ALN). 3T MRN with anatomical coverage from the proximal thigh down to the tibiotalar joint was performed using dual-echo 2-dimensional relaxometry sequences with spectral fat saturation. Detailed quantification of nerve injury by morphometric (cross-sectional area [CSA]) and microstructural MRN markers (proton spin density [ρ], apparent T2-relaxation-time [T2_app ]) was conducted in all study participants.

RESULTS

MRN detected nerve damage in ADP with and without ALN. A proximal-to-distal gradient was identified for nerve T2-weighted (T2w)-signal and T2_app in ADP, indicating a proximal predominance of nerve lesions. While all MRN markers differentiated significantly between ADP and controls, microstructural markers were able to additionally differentiate between subgroups: tibial nerve ρ at thigh level was increased in ALN (p < 0.0001) and in Non-ALN (p = 0.0052) versus controls, and T2_app was higher in ALN versus controls (p < 0.0001) and also in ALN versus Non-ALN (p = 0.0214). T2w-signal and CSA were only higher in ALN versus controls.

CONCLUSIONS

MRN detects and quantifies peripheral nerve damage in ADP in vivo even in the absence of clinically overt ALN. Microstructural markers (T2_app , ρ) are most suitable for differentiating between ADP with and without manifest ALN, and may help to elucidate the underlying pathomechanism in ALN.

The influence of perceived stress and self-control on efficacy of repeated transcranial direct current stimulation in non-treatment-seeking smokers

INTRODUCTION

Transcranial direct current stimulation (tDCS) has recently been raising interest in its therapeutic impact on tobacco use disorder. This study investigates the effects of repeated frontal tDCS (anode: F3, cathode: F4) on cigarette consumption, craving and executive functions.

MATERIAL AND METHODS

In a randomized sham-controlled trial, 24 individuals received active (2.0 mA) and 20 individuals received sham stimulation (0.3 mA) for 20 min on five consecutive days. The participants indicated their tobacco cravings, answered questionnaires and completed neuropsychological tasks at various time points throughout the study. Carbon monoxide (CO) levels and the daily numbers of consumed cigarettes were recorded.

RESULTS

Both intervention groups experienced a significant decrease in the daily number of smoked cigarettes, CO levels, and craving after the stimulation, however, there were no improvements in executive functions. These results did not differ significantly between both intervention groups. Additionally, in the active group, a higher level of perceived stress and a lower level of self-control were linked to a lower cigarette consumption, respectively a higher reduction of the level of CO.

CONCLUSION

This study does not support the hypotheses that tDCS reduces cigarette consumption, attenuates substance craving, or improves executive functions beyond the placebo effect. Our subgroup analysis suggests that high levels of perceived stress and low self-control may be predictors for a successful reduction in cigarette consumption. Furthermore, the placebo effect might be rather high for light smokers, whereas heavy smokers seem to benefit more from the specific effects of tDCS.

CLINICAL TRIAL REGISTRATION NUMBER

NCT03691805.

Predicting Participation in and Success of a Concurrent Smoking Cessation Program during Inpatient Treatment for Alcohol Dependence

BACKGROUND

Predicting participation in and success of smoking cessation programs in alcohol dependent patients has yielded heterogeneous results. Moreover, these findings have rarely been based on prospective studies from clinical routine settings. Identifying predictors in prospective studies could help to tailor interventions that increase participation and success rates of smoking cessation therapies for these patients at a high risk for alcohol- and smoking-related morbidities and mortalities.

SUBJECTS AND METHODS

During inpatient alcohol dependence treatment, 99 nicotine dependent patients were recruited. 73 patients chose to participate in a voluntary smoking cessation program. Interviews and questionnaires were used at baseline and at discharge to assess a large set of variables covering smoking and alcohol related factors, general psychopathology, quality of life and personality traits. Multiple logistic regression models were calculated to predict participation in the smoking cessation program and smoking abstinence at follow-up three months after discharge.

RESULTS

Participation in the smoking cessation program was predicted by higher stage of change, higher confidence in abstaining from smoking and lower perceived stress. Successful smoking cessation at follow-up was predicted by higher expectations of negative physical feelings due to smoking and lower expectations of temptations to smoke at baseline, and by lower number of daily smoked cigarettes at discharge.

CONCLUSION

Despite the small sample size, this prospective study gives a first indication of clinically relevant predictors of participation in and success of a smoking cessation program by exploring many previously reported predictors simultaneously. The findings and their implications for treatment allocation and optimization are discussed.

Baseline severity and the prediction of placebo response in clinical trials for alcohol dependence: A meta-regression analysis to develop an enrichment strategy

BACKGROUND

There is considerable unexplained variability in alcohol abstinence rates (AR) in the placebo groups of randomized controlled trials (RCTs) for alcohol dependence (AD). This is of particular interest because placebo responses correlate negatively with treatment effect size. Recent evidence suggests that the placebo response is lower in very heavy drinkers who show no "spontaneous improvement" prior to treatment initiation (high-severity population) than in a mild-severity population and in studies with longer treatment duration. We systematically investigated the relationship between population severity, treatment duration, and the placebo response in AR to inform a strategy aimed at reducing the placebo response and thereby increasing assay sensitivity in RCTs for AD.

METHODS

We conducted a systematic literature review on placebo-controlled RCTs for AD.We assigned retained RCTs to high- or mild-severity groups of studies based on baseline drinking risk levels and abstinence duration before treatment initiation. We tested the effects of population severity and treatment duration on the placebo response in AR using meta-regression analysis.

RESULTS

Among the 19 retained RCTs (comprising 1996 placebo-treated patients), 11 trials were high-severity and 8 were mild-severity RCTs. The between-study variability in AR was lower in the high-severity than in the mild-severity studies (interquartile range: 7.4% vs. 20.9%). The AR in placebo groups was dependent on population severity (p = 0.004) and treatment duration (p = 0.017) and was lower in the high-severity studies (16.8% at 3 months) than the mild-severity studies (36.7% at 3 months).

CONCLUSIONS

Pharmacological RCTs for AD should select high-severity patients to decrease the magnitude and variability in the placebo effect and and improve the efficiency of drug development efforts for AD.