Safety and efficacy of acamprosate for the treatment of alcohol dependence

The Limbic System in Co-Occurring Substance Use and Anxiety Disorders: A Narrative Review Using the RDoC Framework

Substance use disorders (SUDs) and anxiety disorders (ADs) are highly comorbid, a co-occurrence linked to worse clinical outcomes than either condition alone. While the neurobiological mechanisms involved in SUDs and anxiety disorders are intensively studied separately, the mechanisms underlying their comorbidity remain an emerging area of interest. This narrative review explores the neurobiological processes underlying this comorbidity, using the Research Domain Criteria (RDoC) framework to map disruptions in positive valence, negative valence, and cognitive systems across the three stages of the addiction cycle: binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation. Anxiety and substance use play a reciprocal role at each stage of addiction, marked by significant psychosocial impairment and dysregulation in the brain. A more thorough understanding of the neural underpinnings involved in comorbid SUDs and anxiety disorders will contribute to more tailored and effective therapeutic interventions and assessments.

A critical scientific evaluation of a purportedly negative data report - response to Seneviratne et al. 2022

A core principle in the pursuit of scientific knowledge is that science is self-correcting and that important results should be replicable. Hypotheses need to be reinforced, adjusted, or rejected when novel results are obtained. Replication of results confirms hypotheses and enhances their integration into scientific practice. In contrast, publication of substantiated and replicated negative findings (i.e., non-significant or opposite findings) can be the basis to reject erroneous hypotheses or develop alternative strategies for investigation. Replication is a problem in all research fields. The Psychology Reproductivity Project reported that only 36% of 'highly influential' published research in highly ranked journals were reproduced. Similar to positive data, negative data can be flawed. Errors in a negative data set can be based on methodology, statistics, conceptual defects, and flawed peer review. The peer review process has received progressive scrutiny. A large-scale review of the peer review process of manuscripts submitted to the British Medical Journal group indicated that the process could be characterized as inconsistent, inaccurate, and biased. Further analysis indicated that the peer process is easily manipulated, indicative of a failed system, is a major factor behind the lack of replication in science (acceptance of flawed manuscripts), suppresses opposing scientific evidence and views, and causes gaps in and lack of growth of science. Complicating the integrity of scientific publication is the role of Editors/Researchers. Ethical guidelines exist for major publishing houses about editorial ethics, behavior, and practice.

Incidence and Progression of Alcohol-Associated Liver Disease After Medical Therapy for Alcohol Use Disorder

IMPORTANCE

Alcohol-associated liver disease (ALD) is one of the most devastating complications of alcohol use disorder (AUD), an increasingly prevalent condition. Medical addiction therapy for AUD may play a role in protecting against the development and progression of ALD.

OBJECTIVE

To ascertain whether medical addiction therapy was associated with an altered risk of developing ALD in patients with AUD.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used the Mass General Brigham Biobank, an ongoing research initiative that had recruited 127 480 patients between its start in 2010 and August 17, 2021, when data for the present study were retrieved. The mean follow-up duration from AUD diagnosis was 9.2 years. International Statistical Classification of Diseases and Related Health Problems, Tenth Revision diagnosis codes were used to identify ALD and AUD diagnoses.

EXPOSURES

Medical addiction therapy was defined as the documented use of disulfiram, acamprosate, naltrexone, gabapentin, topiramate, or baclofen. Patients were considered to be treated if they initiated medical addiction therapy before the relevant outcome.

MAIN OUTCOMES AND MEASURES

Adjusted odds ratios (aORs) for the development of ALD and hepatic decompensation were calculated and adjusted for multiple risk factors.

RESULTS

The cohort comprised 9635 patients with AUD, of whom 5821 were male individuals (60.4%), and the mean (SD) age was 54.8 (16.5) years. A total of 1135 patients (11.8%) had ALD and 3906 patients (40.5%) were treated with medical addiction therapy. In multivariable analyses, medical addiction therapy for AUD was associated with decreased incidence of ALD (aOR, 0.37; 95% CI, 0.31-0.43; P < .001). This association was evident for naltrexone (aOR, 0.67; 95% CI, 0.46-0.95; P = .03), gabapentin (aOR, 0.36; 95% CI, 0.30-0.43; P < .001), topiramate (aOR, 0.47; 95% CI, 0.32-0.66; P < .001), and baclofen (aOR, 0.57; 95% CI, 0.36-0.88; P = .01). In addition, pharmacotherapy for AUD was associated with lower incidence of hepatic decompensation in patients with cirrhosis (aOR, 0.35; 95% CI, 0.23-0.53, P < .001), including naltrexone (aOR, 0.27; 95% CI, 0.10-0.64; P = .005) and gabapentin (aOR, 0.36; 95% CI, 0.23-0.56; P < .001). This association persisted even when medical addiction therapy was initiated only after the diagnosis of cirrhosis (aOR, 0.41; 95% CI, 0.23-0.71; P = .002).

CONCLUSIONS AND RELEVANCE

Results of this study showed that receipt of medical addiction therapy for AUD was associated with reduced incidence and progression of ALD. The associations of individual pharmacotherapy with the outcomes of ALD and hepatic decompensation varied widely.

Real-world effectiveness of pharmacological treatments of alcohol use disorders in a Swedish nation-wide cohort of 125 556 patients

BACKGROUND AND AIM

Pharmacotherapy for alcohol use disorder (AUD) is recommendable, but under-used, possibly due to deficient knowledge of medications. This study aimed to investigate the real-world effectiveness of approved pharmacological treatments (disulfiram, acamprosate, naltrexone and nalmefene) of AUD.

DESIGN

A nation-wide, register-based cohort study.

SETTING

Sweden.

PARTICIPANTS

All residents aged 16-64 years living in Sweden with registered first-time treatment contact due to AUD from July 2006 to December 2016 (n = 125 556, 62.5% men) were identified from nation-wide registers.

MEASUREMENTS

The main outcome was hospitalization due to AUD. The secondary outcomes were hospitalization due to any cause, alcohol-related somatic causes, as well as work disability (sickness absence or disability pension), and death. Mortality was analysed with between-individual analysis using a traditional multivariate-adjusted Cox hazards regression model. Recurrent outcomes, such as hospitalization-based events and work disability, were analysed with within-individual analyses to eliminate selection bias.

FINDINGS

Naltrexone combined with acamprosate [hazard ratio (HR) = 0.74; 95% confidence interval (CI) = 0.61-0.89], combined with disulfiram (HR = 0.76, 95% CI = 0.60-0.96) and as monotherapy (HR = 0.89, 95% CI = 0.81-0.97) was associated with a significantly lower risk of AUD-hospitalization compared with no use of AUD medication. Similar results were found for risk of hospitalization due to any cause. Benzodiazepine use and acamprosate monotherapy were associated with an increased risk of AUD-hospitalization (HR = 1.18, 95% CI = 1.14-1.22 and HR = 1.10, 95% CI = 1.04-1.17, respectively). No statistically significant effects were found for work disability or mortality.

CONCLUSIONS

Naltrexone as monotherapy and when combined with disulfiram and acamprosate appears to be associated with lower risk of hospitalization due to any and alcohol-related causes, compared with no use of alcohol use disorder (AUD) medication. Acamprosate monotherapy and benzodiazepine use appear to be associated with increased risk of AUD-associated hospitalization.

Rare Anaphylactic Reaction to Acamprosate in a Young Alcoholic

Alcoholism is a worldwide health issue that affects people from all walks of life. Effective alcohol abuse treatment programs, which combine cognitive behavioral therapy with medications, are necessary to provide the appropriate care that patients need. Treatment options include Naltrexone, Acamprosate, or Disulfiram. Due to poor compliance, Disulfiram is used as a second line agent. These medications play an integral role in treating alcohol abuse. Healthcare providers must be aware of their side effect profiles. This includes a rare and fatal anaphylactic reaction to Acamprosate which is not well documented in the current literature.

High Drinking in the Dark (HDID) mice are sensitive to the effects of some clinically relevant drugs to reduce binge-like drinking

BACKGROUND

There is a serious public health need for better understanding of alcohol use disorder disease mechanisms and for improved treatments. At this writing, only three drugs are approved by the Food and Drug Administration as medications to treat alcohol use disorders - disulfiram, naltrexone, and acamprosate. Binge drinking is a form of abusive alcohol drinking defined by the NIAAA as a drinking to blood alcohol levels (BALs)>0.08% during a period of approximately 2h. To model genetic risk for binge-like drinking, we have used selective breeding to create a unique animal model, High Drinking in the Dark (HDID) mice. Behavioral characterization of HDID mice has revealed that HDID mice exhibit behavioral impairment after drinking, withdrawal after a single binge-drinking session, and escalate their intake in response to induction of successive cycles of dependence. Notably, HDID mice do not exhibit altered tastant preference or alcohol clearance rates. We therefore asked whether drugs of known clinical relevance could modulate binge-like ethanol drinking in HDID mice, reasoning that this characterization of HDID responses should inform future use of this genetic animal model for screening and development of novel potential therapeutics.

METHODS

We tested the efficacy of acamprosate and naltrexone to reduce binge-like drinking in HDID mice. Additionally, we tested the GABAB receptor agonist, baclofen, based on recent pre-clinical and clinical studies demonstrating that it reduces alcohol drinking. We elected not to include disulfiram due to its more limited clinical usage. Mice were tested after acute doses of drugs in the limited-access Drinking in the Dark (DID) paradigm.

RESULTS

HDID mice were sensitive to the effects of acamprosate and baclofen, but not naltrexone. Both drugs reduced binge-like drinking. However, naltrexone failed to reduce drinking in HDID mice. Thus, HDID mice may represent a useful model for screening novel compounds.

Genetic and pharmacological manipulation of glyoxalase 1 regulates voluntary ethanol consumption in mice

Previous studies have identified an association between the gene glyoxalase 1 (Glo1) and anxiety-like behavior in mice and have shown that the substrate of GLO1, methylglyoxal, is a competitive partial agonist at GABA_A receptors. Given the well-established role of GABA_A receptors in the behavioral effects of ethanol (EtOH), we investigated the role of Glo1 in voluntary EtOH consumption in mice using the drinking in the dark (DID) paradigm. Transgenic mice overexpressing Glo1 on both FVB/NJ (FVB) or C57BL/6J (B6) backgrounds showed increased voluntary EtOH consumption compared to their wild-type littermates in DID. Furthermore, transgenic Glo1 knockdown mice on a B6 background showed decreased voluntary EtOH consumption in DID. These genetic manipulations of Glo1 had no effect on sucrose, saccharin or water consumption. Finally, we found that a small molecule GLO1 inhibitor (S-bromobenzylglutathione cyclopentyl diester (pBBG; 6.25, 12.5 mg/kg)) reduced EtOH consumption compared to vehicle treated B6 mice without altering saccharin or water consumption. Sucrose consumption was only reduced by the higher (12.5 mg/kg) dose of pBBG. We did not observe differences in the loss of righting reflex (LORR) or EtOH-induced foot slips on the balance beam in response to acute EtOH administration (LORR: 4 g/kg, Balance Beam: 1.25 g/kg) in B6 or FVB mice overexpressing Glo1, nor in B6 mice treated with pBBG. These data are the first to implicate Glo1 in EtOH-related behaviors and suggest that GLO1 inhibitors may have therapeutic potential for the treatment of alcohol use disorders.

An inpatient treatment and discharge planning protocol for alcohol dependence: efficacy in reducing 30-day readmissions and emergency department visits

BACKGROUND

Alcohol dependence results in multiple hospital readmissions, but no discharge planning protocol has been studied to improve outcomes. The inpatient setting is a frequently missed opportunity to discuss treatment of alcohol dependence and initiate medication-assisted treatment, which is effective yet rarely utilized.

AIM

Our aim was to implement and evaluate a discharge planning protocol for patients admitted with alcohol dependence.

SETTING

The study took place at the San Francisco General Hospital (SFGH), a university-affiliated, large urban county hospital.

PARTICIPANTS

Learner participants included Internal Medicine residents at the University of California, San Francisco (UCSF) who staff the teaching service at SFGH. Patient participants included inpatients with alcohol dependence admitted to the Internal Medicine teaching service.

PROGRAM DESCRIPTION

We developed and implemented a discharge planning protocol for patients admitted with alcohol dependence that included eligibility assessment and initiation of medication-assisted treatment.

PROGRAM EVALUATION

Rates of medication-assisted treatment increased from 0% to 64% (p value < 0.001). All-cause 30-day readmission rates to SFGH decreased from 23.4% to 8.2% (p value = 0.042). All-cause emergency department visits to SFGH within 30 days of discharge decreased from 18.8% to 6.1% (p value = 0.056).

DISCUSSION

Through implementation of a discharge planning protocol by Internal Medicine residents for patients admitted with alcohol dependence, there was a statistically significant increase in medication-assisted treatment and a statistically significant decrease in both 30-day readmission rates and emergency department visits.

The development of acamprosate as a treatment against alcohol relapse

INTRODUCTION

Globally, alcohol abuse and dependence are significant contributors to chronic disease and injury and are responsible for nearly 4% of all deaths annually. Acamprosate (Campral), one of only three pharmacological treatments approved for the treatment of alcohol dependence, has shown mixed efficacy in clinical trials in maintaining abstinence of detoxified alcoholics since studies began in the 1980s. Yielding inconsistent results, these studies have prompted skepticism.

AREAS COVERED

Herein, the authors review the preclinical studies which have assessed the efficacy of acamprosate in various animal models of alcohol dependence and discuss the disparate findings from the major clinical trials. Moreover, the authors discuss the major limitations of these preclinical and clinical studies and offer explanations for the often-contradictory findings. The article also looks at the importance of the calcium moiety that accompanies the salt form of acamprosate and its relevance to its activity.

EXPERT OPINION

The recent discovery that large doses of calcium largely duplicate the effects of acamprosate in animal models has introduced a serious challenge to the widely held functional association between this drug and the glutamate neurotransmission system. Future research on acamprosate or newer pharmacotherapeutics should consider assessing plasma and/or brain levels of calcium as a correlate or mediating factor in anti-relapse efficacy. Further, preclinical research on acamprosate has thus far lacked animal models of chemical dependence on alcohol, and the testing of rodents with histories of alcohol intoxication and withdrawal is suggested.

The dopamine system and alcohol dependence

Alcohol dependence is a common mental disorder that is associated with substantial disease burden. Current efforts at prevention and treatment of alcohol dependence are of very limited effectiveness. A better understanding of the biological mechanisms underlying dependence is essential to improving the outcomes of treatment and prevention initiatives. To date, most of the efforts have focused on the key role of the dopamine system in the complex etiological network of alcohol dependence. This review summarizes current research about the relationships between alcohol consumption and the dopaminergic system. We find that many of the currently available studies have contradictory results, presumably due to differences in methodology, non-linear dosage effects, use of different samples, and the possible confounding effects of other neurotransmitter systems.

Increased extracellular glutamate in the nucleus accumbens promotes excessive ethanol drinking in ethanol dependent mice

Using a well-established model of ethanol dependence and relapse, this study examined adaptations in glutamatergic transmission in the nucleus accumbens (NAc) and their role in regulating voluntary ethanol drinking. Mice were first trained to drink ethanol in a free-choice, limited access (2 h/day) paradigm. One group (EtOH mice) received repeated weekly cycles of chronic intermittent ethanol (CIE) exposure with intervening weeks of test drinking sessions, whereas the remaining mice (CTL mice) were similarly treated but did not receive CIE treatment. Over repeated cycles of CIE exposure, EtOH mice exhibited significant escalation in drinking (up to ∼3.5 g/kg), whereas drinking remained relatively stable at baseline levels (2-2.5 g/kg) in CTL mice. Using in vivo microdialysis procedures, extracellular glutamate (GLUEX) levels in the NAc were increased approximately twofold in EtOH mice compared with CTL mice, and this difference was observed 7 days after final CIE exposure, indicating that this hyperglutamatergic state persisted beyond acute withdrawal. This finding prompted additional studies examining the effects of pharmacologically manipulating GLUEX in the NAc on ethanol drinking in the CIE model. The non-selective glutamate reuptake antagonist, threo-β-benzyloxyaspartate (TBOA), was bilaterally microinjected into the NAc and found to dose-dependently increase drinking in nondependent (CTL) mice to levels attained by dependent (EtOH) mice. TBOA also further increased drinking in EtOH mice. In contrast, reducing glutamatergic transmission in the NAc via bilateral injections of the metabotropic glutamate receptor-2/3 agonist LY379268 reduced drinking in dependent (EtOH) mice to nondependent (CTL) levels, whereas having a more modest effect in decreasing ethanol consumption in CTL mice. Taken together, these data support an important role of glutamatergic transmission in the NAc in regulating ethanol drinking. Additionally, these results indicate that ethanol dependence produces adaptations that favor elevated glutamate activity in the NAc which, in turn, promote excessive levels of ethanol consumption associated with dependence.

Alcohol use disorder: pathophysiology, effects, and pharmacologic options for treatment

Alcohol use disorders (AUD) continue to be a concerning health issue worldwide. Harmful alcohol use leads to 2.5 million deaths annually worldwide. Multiple options exist for the management of dependence on alcohol, not all of which are approved by drug-regulating agencies. Current practice in treating AUD does not reflect the diversity of pharmacologic options that have potential to provide benefit, and guidance for clinicians is limited. Few medications are approved for treatment of AUD, and these have exhibited small and/or inconsistent effects in broad patient populations with diverse drinking patterns. The need for continued research into the treatment of this disease is evident in order to provide patients with more specific and effective options. This review describes the neurobiological mechanisms of AUD that are amenable to treatment and drug therapies that target pathophysiological conditions of AUD to reduce drinking. In addition, current literature on pharmacologic (both approved and non-approved) treatment options for AUD offered in the United States and elsewhere are reviewed. The aim is to inform clinicians regarding the options for alcohol abuse treatment, keeping in mind that not all treatments are completely successful in reducing craving or heavy drinking or increasing abstinence.

Neurochemical mechanisms of alcohol withdrawal

Alcohol dependence encompasses a serious medical and societal problem that constitutes a major public health concern. A serious consequence of dependence is the emergence of symptoms associated with the alcohol withdrawal syndrome when drinking is abruptly terminated or substantially reduced. Clinical features of alcohol withdrawal include signs of central nervous system hyperexcitability, heightened autonomic nervous system activation, and a constellation of symptoms contributing to psychologic discomfort and negative affect. The development of alcohol dependence is a complex and dynamic process that ultimately reflects a maladaptive neurophysiologic state. Perturbations in a wide range of neurochemical systems, including glutamate, γ-aminobutyric acid, monoamines, a host of neuropeptide systems, and various ion channels produced by the chronic presence of alcohol ultimately compromise the functional integrity of the brain. These neuroadaptations not only underlie the emergence and expression of many alcohol withdrawal symptoms, but also contribute to enhanced relapse vulnerability as well as perpetuation of uncontrolled excessive drinking. This chapter highlights the hallmark features of the alcohol withdrawal syndrome, and describes neuroadaptations in a wide array of neurotransmitter and neuromodulator systems (amino acid and monoamine neurotransmitter, neuropeptide systems, and various ion channels) as they relate to the expression of various signs and symptoms of alcohol withdrawal, as well as their relationship to the significant clinical problem of relapse and uncontrolled dangerous drinking.

The role of clock in ethanol-related behaviors

Mice with a mutation in the Clock gene (ClockΔ19) exhibit increased preference for stimulant rewards and sucrose. They also have an increase in dopaminergic activity in the ventral tegmental area (VTA) and a general increase in glutamatergic tone that might underlie these behaviors. However, it is unclear if their phenotype would extend to a very different class of drug (ethanol), and if so, whether these systems might be involved in their response. Continuous access voluntary ethanol intake was evaluated in ClockΔ19 mutants and wild-type (WT) mice. We found that ClockΔ19 mice exhibited significantly increased ethanol intake in a two-bottle choice paradigm. Interestingly, this effect was more robust in female mice. Moreover, chronic ethanol experience resulted in a long-lasting decrease in VTA Clock expression. To determine the importance of VTA Clock expression in ethanol intake, we knocked down Clock expression in the VTA of WT mice via RNA interference. We found that reducing Clock expression in the VTA resulted in significantly increased ethanol intake similar to the ClockΔ19 mice. Interestingly, we also discovered that ClockΔ19 mice exhibit significantly augmented responses to the sedative effects of ethanol and ketamine, but not pentobarbital. However, their drinking behavior was not affected by acamprosate, an FDA-approved drug for the treatment of alcoholism, suggesting that their increased glutamatergic tone might underlie the increased sensitivity to the sedative/hypnotic properties of ethanol but not the rewarding properties of ethanol. Taken together, we have identified a significant role for Clock in the VTA as a negative regulator of ethanol intake and implicate the VTA dopamine system in this response.