Reward drinking and naltrexone treatment response among young adult heavy drinkers

The association between pain and negative alcohol-related consequences among college students engaged in binge drinking: The moderating role of reward and relief drinking motives

Binge drinking, defined as consuming 4 or more drinks for females and 5 or more for males within a two-hour timeframe, is common among college students and associated with harmful health outcomes. Similarly, pain is prevalent in this population and can negatively affect students' psychological, social, and academic functioning. However, the limited research examining associations between pain and alcohol-related constructs among college students has yielded inconsistent results. Individual differences in levels of reward and relief drinking motives (i.e., drinking in response to positive affect/social situations versus negative affect/stressful situations) may contribute to the complex, heterogeneous nature of these associations. The aim of the present study was to examine the moderating effects of reward and relief drinking on the association between pain and alcohol-related negative consequences in college students who binge drink. Participants were 436 college students who had engaged in past-month binge drinking. Most participants identified as White (66.7 %) and female (78.2 %), with a mean age of 19.62 (SD = 1.56) years. Results revealed significant moderating effects of both reward and relief motives on the association between pain at time 1 and alcohol-related negative consequences at time 2. In participants with either higher levels of relief or lower levels of reward drinking greater pain was significantly associated with a higher number of alcohol-related negative consequences. In participants demonstrating higher levels of reward drinking, greater pain was significantly associated with a lower number of alcohol-related negative consequences. Our work indicates targeting pain as a possible intervention to prevent alcohol-related negative consequences among those who report lower levels of reward or higher levels of relief drinking.

Exploratory structural neuroimaging examination of impulsivity in severe alcohol use disorder: Persistent implication of the ventral striatum

BACKGROUND

While Alcohol Use Disorder (AUD) is frequently associated with impulsivity, its structural brain substrates are still poorly defined. The triadic model of addiction postulates that impulsive behavior is regulated by an amygdalo-striatal impulsive subcomponent, a prefrontal and cerebellar reflective subcomponent, and an insular regulatory subcomponent. The objective of this study was thus to examine the relationships between self-evaluated impulsivity and structural brain abnormalities in patients with severe AUD (sAUD) using the triadic model as a theoretical framework.

METHODS

Twenty-two inpatients with sAUD and 17 Healthy Controls (HC) completed two impulsivity scales: the Barratt Impulsiveness Scale-11 (BIS-11), and the Urgency, Premeditation, Perseverance, Sensation Seeking, Positive Urgency Impulsive Behavior Scale (UPPS). They also underwent an anatomical MRI. The brain volumes of the regions described as involved in the three subcomponents of the triadic model were extracted.

RESULTS

The two groups did not significantly differ on self-reported impulsivity measures. However, the volumes of the caudate nuclei, executive cerebellum and insula were smaller in sAUD than in HC. In the sAUD group there were significant positive correlations between certain impulsivity measures and gray matter volume of the nucleus accumbens.

CONCLUSIONS

In sAUD, self-evaluated impulsivity specifically relates to the integrity of the ventral striatum that belongs to the impulsive subcomponent of the triadic neurocognitive model of addiction. It is not related to the integrity or deterioration of the brain regions that underlie the reflexive or regulatory sub-component. Although these results have methodological limitations, they are consistent with the impulsive/compulsive model of addiction and confirms the persistence of the relationship between impulsivity and ventral striatum in sAUD.

Comparing the psychometric properties of reward and relief drinking measures

Previous work examining the extent to which individuals seek alcohol to enhance positive experiences (reward drinking) or relieve aversive states (relief drinking) has shown that reward/relief drinking predicts response to naltrexone and acamprosate treatment for alcohol use disorder. Yet, various measures of reward/relief drinking have been used in prior research, and the comparative psychometric properties of these measures are unknown. Evaluating and comparing the psychometric properties of these reward/relief drinking measures could identify measures with the most promise for translating precision medicine findings to clinical practice. In a community sample of 65 individuals with heavy/hazardous alcohol use on the Alcohol Use Disorder Identification Test, we showed good internal consistency reliability, test-retest reliability, and concurrent validity for theoretically aligned measures (e.g., reward drinking and reward responsiveness, relief drinking and depression/anxiety symptoms) of the reward and relief subscales across the six measures. We then used ecological momentary assessment to determine whether reward and relief drinking subscales predicted within-person associations between contextual factors of interest (e.g., negative affect, positive affect, distress intolerance, physical pain, hangover symptoms, social drinking situations, alcohol cues) and same-moment alcohol craving. All six measures demonstrated limited predictive validity for alcohol craving contexts in daily life as assessed via ecological momentary assessment. Despite these findings, reward and relief drinking measures show good reliability and concurrent validity and previously demonstrated clinical utility for predicting response to alcohol use disorder treatments, including naltrexone. Future research should aim to elucidate the mechanisms underlying the association between responses to reward/relief drinking measures and pharmacotherapy outcomes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Characterizing reward and relief/habit drinking profiles in a study of naltrexone, varenicline, and placebo

INTRODUCTION

This study aims to clarify differences in mood, craving, and treatment response between reward and relief/habit individuals in a study of naltrexone, varenicline, and placebo. We hypothesized that relief/habit individuals would have a poorer mood during early abstinence and higher levels of alcohol craving than reward individuals. We hypothesized that reward individuals would demonstrate better drinking outcomes on naltrexone versus placebo.

METHODS

Data were culled from a randomized, double-blind, placebo-controlled human trial of 53 individuals (18F/16M) with alcohol use disorder randomized to varenicline (n = 19), naltrexone (n = 15), or matched placebo (n = 19). In this 6-day practice quit trial, participants attempted to abstain from drinking and completed daily diaries. Participants were classified into reward or relief/habit subgroups based on self-reported motivation for drinking. Multilinear models tested differences in mood and alcohol craving between reward and relief/habit individuals. General linear models tested differences between reward and relief/habit individuals' drinking outcomes on each medication versus placebo.

RESULTS

Relief/habit individuals showed decreases in positive mood and increases in negative mood over the quit attempt across medications, compared to reward individuals (P's < .05). Reward individuals' tension decreased on naltrexone, while relief/habit individuals' tension remained stable (F = 3.64, P = .03). Reward individuals in the placebo group had higher percent days abstinent than relief individuals in the placebo group (P < .001).

DISCUSSION

This study suggests relief/habit individuals' mood worsens during early abstinence. Our finding that reward individuals' tension decreased on naltrexone and increased on placebo may suggest a clinical response to the medication.

AUD in perspective

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

Examining the validity of the addictions neuroclinical assessment domains in a crowdsourced sample of adults with current alcohol use

Several dimensional frameworks for characterizing heterogeneity in alcohol use disorder (AUD) have been proposed, including the Addictions Neuroclinical Assessment (ANA). The ANA is a framework for assessing individual variability within AUD across three domains corresponding to the proposed stages of the addiction cycle: reward (binge-intoxication stage), negative emotionality (withdrawal-negative affect stage), and cognitive control (preoccupation-anticipation stage). Recent work has evaluated the ANA's three-factor structure and construct validity, primarily in treatment-seekers with AUD. We extended this research by examining the factor structure, bias across alcohol use severity, longitudinal invariance, and concurrent and predictive validity of a novel assessment of the ANA domains in adults with past 12-month regular (10 + alcohol units/week) alcohol use. Participants recruited from Prolific (N = 732), a crowdsourced data collection platform, completed various self-report measures. A test-retest subsample (n = 234) completed these measures 30 days later. Split-half exploratory factor analysis and confirmatory factor analysis supported the three-factor structure of the ANA. The overall factor structure was invariant across 30 days. Concurrently and prospectively, ANA domains demonstrated convergent validity concerning theoretically aligned alcohol-related, psychological, and personality measures. However, there was evidence of poor discriminant validity, and several cognitive control and reward items demonstrated bias across alcohol use severity. Future research is needed to improve the measurement of ANA domains using multimodal indicators, examine longitudinal changes in domains and their relationship with alcohol use severity, characterize phenotypic subgroups based on relative levels of domains, and compare the utility of the ANA with other proposed frameworks for measuring AUD heterogeneity. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Habit-, reward- and fear-related motivations in alcohol use disorder: A one-year prospective study

OBJECTIVE

Cross-sectional studies show that habitual use of alcohol is associated with severity of alcohol dependence reflected across a range of domains and lower number of detoxifications in multiple settings. In this study, we investigated whether alcohol use disorder (AUD) patients with greater habitual use of alcohol at baseline showed worse outcomes after one year of follow-up.

METHODS

A sample of inpatients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) alcohol use disorder (AUD) was assessed at baseline (n = 50) and after one year (n = 30). The Habit, Reward, and Fear Scale (HRFS) was employed to quantify affective (fear or reward) and non-affective (habitual) drives for alcohol use, the Alcohol Dependence Scale (ADS) was used to assess clinical outcomes, and the Depression, Anxiety and Stress Scale (DASS-21) was used to quantify and control for associated affective symptoms.

RESULTS

There was a significant reduction in the three HRFS scores at the follow-up. Regression analyses demonstrated that greater habit- and fear-related drives at baseline predicted greater decreases in the ADS scores at the endpoint. However, after controlling for age, sex and affective symptoms, only reward and fear were associated with reductions in ADS scores at the end of one year. Prescriptions of naltrexone and antidepressants/benzodiazepines did not predict decreases in reward and fear-related motivations.

CONCLUSION

Although we were unable to confirm that habitual subscores at baseline predict worse long-term outcomes among inpatients with AUD, we found that a greater fear and reward motives for the use of alcohol predicted a greater magnitude of improvement in the AUD symptoms after one year. We hope that these findings will help develop new approaches toward AUD treatment and inform models of addiction research.

Examining the validity of the drinking motives questionnaire for identifying reward and relief drinking subgroups in college students

BACKGROUND

Heavy alcohol use in college is associated with a risk of developing alcohol use disorder. Characterizing variability in individual risk factors for alcohol use could help mitigate risk by informing personalized approaches to prevention. This study examined the validity of a brief measure for identifying reward/relief drinking phenotypes in non-treatment-seeking young adults.

METHODS

College students (n = 454) who reported binge drinking completed the Drinking Motives Questionnaire-Revised-Short Form (DMQ-R-SF). Confirmatory factor and latent profile analyses (CFA; LPA) of the DMQ-R-SF were performed to assess structural validity and identify reward/relief drinking subgroups. We compared models measuring reward drinking with the DMQ-R-SF enhancement motives (reward-enhancement) subscale to models measuring reward drinking with enhancement and social motives (reward-enhancement/social). Across models, relief drinking was measured with coping motives. We examined associations between reward/relief drinking subgroups and alcohol and personality variables concurrently and prospectively at a 6-week follow-up.

RESULTS

A two-factor reward and relief structure of the DMQ-R-SF was supported. Three latent profiles were identified (low reward/low relief: n = 133, high reward/low relief: n = 249; high reward/high relief: n = 72). Both CFA and LPA models that utilized reward-enhancement/social items indicated a better fit than reward-enhancement items alone. At baseline, individuals in the high-reward/high-relief profile demonstrated the poorest alcohol use outcomes and higher negative affect. Those in the high-reward/low-relief profile demonstrated greater alcohol use severity than those in the low-reward/low-relief profile. Prospectively, individuals classified in the high-reward/low-relief subgroup reported greater binge drinking frequency and those in the high-reward/high-relief profile reported greater alcohol consequences.

CONCLUSIONS

The DMQ-R-SF is a valid measure for identifying reward and relief drinking subgroups in college students with binge drinking and could have utility for precision prevention efforts that target individuals in the high-reward/low-relief and high-reward/high-relief subgroups.

An intensive longitudinal examination of topiramate treatment for alcohol use disorder: a secondary analysis of data from a randomized controlled trial

BACKGROUND AND AIMS

Previous findings have been equivocal as to whether a single-nucleotide polymorphism (rs2832407) in GRIK1, which encodes a glutamate receptor subunit, moderates the effects of topiramate treatment for drinking reduction. We leveraged intensive longitudinal data to provide greater precision and allow an examination of intermediate outcomes addressing this question. We used data from a randomized controlled trial (RCT) to test the hypotheses that topiramate treatment reduces daily heavy drinking, desire to drink and positive alcohol expectancies and that these effects are stronger in rs2832407*C-allele homozygotes.

DESIGN

Secondary data analysis of a randomized controlled trial.

SETTING

University of Pennsylvania Treatment Research Center in the United States.

PARTICIPANTS/CASES

Participants were 164 individuals (70.1% male, mean age = 51.42, 36.0% rs2832407*C-allele homozygotes) who sought to reduce or stop drinking.

INTERVENTION AND COMPARATOR

Participants were assigned to medication (topiramate or placebo), with stratification by genotype group (CC versus AA/AC) and treatment goal (reduce versus abstain).

MEASUREMENTS

During the 12-week treatment period, participants completed daily interactive voice response (IVR) surveys.

FINDINGS

On any given day during treatment, participants who received topiramate had lower odds of IVR-reported heavy drinking [odds ratio (OR) = 0.259, b (standard error, SE) = -1.351 (0.334), P < 0.001] and lower levels of desire to drink [b (SE) = -0.323 (0.122), P = 0.009] and positive alcohol expectancies [b (SE) = -0.347 (0.138), P = 0.013] than those who received placebo. Participants who received topiramate also reported greater reductions in positive alcohol expectancies during the first 2 weeks of treatment than those who received placebo [b (SE) = -0.028 (0.008), P = 0.001], but topiramate did not impact the daily rate of change in heavy drinking or desire to drink. Genotype did not moderate the effects of topiramate on any outcomes examined (P > 0.05).

CONCLUSIONS

Topiramate is an effective medication for individuals seeking to reduce heavy drinking. The effects are not moderated by the single-nucleotide polymorphism rs2832407.

Using naltrexone to validate a human laboratory test system to screen new medications for alcoholism (TESMA)- a randomized clinical trial

This registered clinical trial sought to validate a laboratory test system devised to screen medications for alcoholism treatment (TESMA) under different contingencies of alcohol reinforcement. Forty-six nondependent, but at least medium-risk drinkers were given the opportunity to earn intravenous infusions of ethanol, or saline, as rewards for work in a progressive-ratio paradigm. Work demand pattern and alcohol exposure dynamics were devised to achieve a gradual shift from low-demand work for alcohol (WFA) permitting quickly increasing breath alcohol concentrations (BrAC) to high-demand WFA, which could only decelerate an inevitable decrease of the previously earned BrAC. Thereby, the reward contingency changed, modeling different drinking motivations. The experiment was repeated after at least 7 days of randomized, double-blinded treatment with naltrexone, escalated to 50 mg/d, or placebo. Subjects treated with naltrexone reduced their cumulative WFA (cWFA) slightly more than participants receiving placebo. This difference was not statistically significant in the preplanned analysis of the entire 150 min of self-administration, i.e., our primary endpoint (p = 0.471, Cohen's d = 0.215). Naltrexone serum levels correlated with change in cWFA (r = -0.53; p = 0.014). Separate exploratory analyses revealed that naltrexone significantly reduced WFA during the first, but not the second half of the experiment (Cohen's d = 0.643 and 0.14, respectively). Phase-dependent associations of WFA with changes in subjective stimulation, wellbeing and desire for alcohol suggested that the predominant reinforcement of WFA was positive during the first phase only, and might have been negative during the second. We conclude that the TESMA is a safe and practical method. It bears the potential to quickly and efficiently screen new drugs for their efficacy to attenuate positively reinforced alcohol consumption. It possibly also provides a condition of negative reinforcement, and for the first time provides experimental evidence suggesting that naltrexone's effect might depend on reward contingency.

Selecting the appropriate hurdles and endpoints for pentilludin, a novel antiaddiction pharmacotherapeutic targeting the receptor type protein tyrosine phosphatase D

Substance use disorders provide challenges for development of effective medications. Use of abused substances is likely initiated, sustained and "quit" by complex brain and pharmacological mechanisms that have both genetic and environmental determinants. Medical utilities of prescribed stimulants and opioids provide complex challenges for prevention: how can we minimize their contribution to substance use disorders while retaining medical benefits for pain, restless leg syndrome, attention deficit hyperactivity disorder, narcolepsy and other indications. Data required to support assessments of reduced abuse liability and resulting regulatory scheduling differs from information required to support licensing of novel prophylactic or therapeutic anti-addiction medications, adding further complexity and challenges. I describe some of these challenges in the context of our current efforts to develop pentilludin as a novel anti-addiction therapeutic for a target that is strongly supported by human and mouse genetic and pharmacologic studies, the receptor type protein tyrosine phosphatase D (PTPRD).

Translational models of addiction phenotypes to advance addiction pharmacotherapy

Alcohol and substance use disorders are heterogeneous conditions with limited effective treatment options. While there have been prior attempts to classify addiction subtypes, they have not been translated into clinical practice. In an effort to better understand heterogeneity in psychiatric disorders, the National Institute for Mental Health Research Domain Criteria (RDoC) has challenged scientists to think beyond diagnostic symptoms and to consider the underlying features of psychopathology from a neuroscience-based framework. The field of addiction has grappled with this approach by considering several key constructs with the potential to capture RDoC domains. This critical review will focus on the efforts to apply translational models of addiction phenomenology in human clinical samples, including their relative strengths and weaknesses. Opportunities for forward and reverse translation are also discussed. Deep behavioral phenotyping using neuroscience-informed batteries shows promise for a better understanding of the clinical neuroscience of addiction and advancing precision medicine for alcohol and substance use disorders.

Examining a brief measure and observed cutoff scores to identify reward and relief drinking profiles: Psychometric properties and pharmacotherapy response

BACKGROUND

Precision medicine approaches attempt to reduce variability in alcohol use disorder (AUD) outcomes by identifying patient characteristics that predict response to a particular treatment. Recent work has examined the extent to which individuals with AUD may seek alcohol to enhance positive experiences (reward drinking) or relieve negative states (relief drinking) and shown that a high reward/low relief phenotype predicts naltrexone treatment response. Yet, limitations of reward/relief drinking measures may hamper efforts to translate findings to clinical practice. We sought to refine a brief measure of reward/relief drinking and develop cutoff scores to identify reward/relief subgroups that predict pharmacotherapy response.

METHODS

The Inventory of Drinking Situations (IDS), used in previous studies to measure reward/relief drinking, was administered to 426 participants (77% male; average age = 45.3) in a clinical trial examining naltrexone and acamprosate.

RESULTS

Item response theory and tests of differential item functioning across sex, age, and alcohol dependence severity were used to create a 10-item measure, titled the Reward and Relief IDS (RR-IDS). Cutoff scores on the RR-IDS for the reward/relief drinking subgroups were identified using latent profile and area under the curve analyses. The cutoff scores demonstrated good construct validity. Individuals in the high reward/low relief subgroup who received naltrexone or acamprosate had a decreased likelihood of heavy drinking (large effect sizes) versus those who received placebo.

CONCLUSIONS

The RR-IDS is a practical measure for identifying reward/relief subgroups and predicting pharmacotherapy response. Pending replication of these findings, the RR-IDS could be a critical precision medicine tool for prescribing AUD medications.

Naltrexone moderates the association of alcohol use and affect among adolescent drinkers in daily life

BACKGROUND

Naltrexone is an efficacious medication for the treatment of alcohol use disorder in adults. As an opioid receptor antagonist, naltrexone blocks activation of the endogenous opioid system, which is involved in the affectively reinforcing properties of substance use. Few studies, however, have examined the moderating effect of naltrexone on the association between affect and alcohol use. Additionally, most existing research on naltrexone has been with adults in the human laboratory.

METHOD

We conducted a secondary analysis of ecological momentary assessment data from a randomized, double-blinded, placebo-controlled cross-over study that compared naltrexone (50 mg/daily) and placebo in 26 adolescents (15 to 19 years old) who exhibited problematic drinking patterns. Multilevel models tested whether naltrexone moderated associations of alcohol use with both positive and negative affect (PA, NA).

RESULTS

Results indicated that, during naltrexone treatment, greater estimated blood alcohol concentration (eBAC) levels were associated with greater NA further into drinking episodes. In turn, greater NA after the first drink of an episode was associated with reduced subsequent eBAC values during naltrexone treatment. Low PA was also associated with lower subsequent eBAC levels in the naltrexone condition after the first drink.

CONCLUSIONS

These findings support the idea that naltrexone can disrupt the association between affect and alcohol use, effects that emerge later in drinking episodes. Greater attention to the effects of naltrexone on affect and reinforcement may help to tailor psychotherapy to maximize the benefits of naltrexone. However, in the present study, as most drink reports were in the first 2 h of the drinking episode and participants reported affect only at the first three end-drink reports of a drinking episode (limiting the number of drinks reported), we had reduced power to detect effects in the continuation phase. Thus, replication of the findings is needed using a design that assesses the impact of naltrexone across the entire episode.