Antipsychotic drugs in cocaine dependence: A systematic review and meta-analysis

Gender and addiction and other mental disorders comorbidity: sociodemographic, clinical, and treatment differences

The co-occurrence of substance use disorders (SUD) and other mental disorders (OMD) is assumed to be high, but the details are uncertain in Spain. The objective of the present study was to know the prevalence of this comorbidity, as well as the pharmacological treatment, both in specific addiction treatment networks and in mental health networks, with a gender perspective. Observational, multicenter study, with a randomized sample, of patients under treatment for SUD or OMD in Spain (N = 1783). A specific questionnaire, collecting sociodemographic and clinical variables, diagnosed SUD and OMD, and prescribed psychotropic drugs, was completed by treating clinicians. Differences between females and males were searched. A high prevalence of OMD was found in those patients treated for their SUD (71%), and also of diagnoses of SUD (59%) in people treated for OMD. Significant relationships between addiction to certain substances and specific mental disorders were found (with no main differences between women and men). The treatments for OMD were very common in the addiction treatment networks, but that of SUDs in those patients treated in the mental health networks was less than expected. A high prescription of benzodiazepines was found. Women were less frequently diagnosed with cannabis, opioid, and especially cocaine use disorders, and they had fewer psychotic disorders and more affective, anxiety, sleep, and eating disorders, with the rest being the same, including personality disorders. Women had fewer treatments with agonists and more with antagonists, and more prescriptions of anxiolytics and antidepressants. This study provides preliminary information on the coexistence in routine clinical practice of addictive disorders and other mental disorders in Spain, and on the treatment provided, and shows differences in prevalence and clinical characteristics, and especially in treatment approaches between women and men. Thus, should be useful to adapt the treatment response with greater precision, and with a gender perspective.

Differences in Substance Use Disorders and Other Mental Disorders in Mental Health and Addiction Settings: Sociodemographic, Clinical, Drug Treatment, and Gender Differences

Different care networks in Spain evaluate the co-occurrence of substance use disorders (SUD) and other mental disorders (OMDs). This study aimed to explore the differences in prevalence, sociodemographic and clinical profile, pharmacological treatment, and gender perspective of the co-occurrence of SUD and OMD between specific addiction treatment networks and mental health networks. This is an observational, cross-multicenter study with a randomized sample of patients under treatment for SUD or OMDs in different autonomous communities of Spain (N = 1783). Sixty-seven health professionals completed an ad hoc online questionnaire, collecting sociodemographic variables with patients diagnosed with SUD and OMDs, and their pharmacological treatments. The findings revealed a high prevalence of OMD in patients treated for SUD (71%) and those for OMD diagnosed with SUD (59%). Specific relationships between the SUDs and OMDs were identified. In networks treating SUDs, the increase in treatment for OMDs was widespread. However, the addition of SUD treatments in mental health networks was less frequent than expected. In addition, an elevated benzodiazepine prescription was detected in both settings. Some possible gender biases in treatments were found. This study provides preliminary information on the coexistence in routine clinical practice of addictive disorders and other mental disorders in Spain. The results revealed that the treatments provided are inefficient for SUDs in patients treated in mental health settings. Furthermore, a high prescription of anxiolytics and differences by sex are shown. These findings may contribute to adapting the treatment response with greater precision and effectiveness.

A randomized, double-blind, placebo-controlled trial of ondansetron for the treatment of cocaine use disorder with post hoc pharmacogenetic analysis

BACKGROUND

Cocaine use disorder (CUD) has significant consequences and there remain no FDA-approved pharmacotherapies. Ondansetron is an indirect dopaminergic modulator that has shown efficacy in alcohol use disorder, particularly in phenotypic and genotypic subgroups, and was found to be efficacious in a pilot dose-finding trial for CUD.

METHODS

One-hundred eight (108) adults with CUD were randomized to ondansetron 4 mg twice daily or placebo for 9 weeks and assessed up to thrice weekly to evaluate self-reported cocaine use and urine benzoylecgonine. Participants received cognitive-behavioral therapy and brief behavioral compliance enhancement therapy. Consenting participants (N = 79) provided blood samples for exploratory pharmacogenetic analyses.

RESULTS

Participants in both arms reduced cocaine use over time, but there was no statistically significant difference on percentage of cocaine-free days (PCFD; p = 0.972) or percentage of cocaine-free urine samples (PCFU; p = 0.909). Participants with early-onset CUD had greater improvement regardless of study arm (p = 0.002). Post hoc pharmacogenetic analyses demonstrated an interaction effect between treatment and rs1176713 SNP on PCFU in the total sample (p = 0.040) and African ancestry subset (p = 0.03). Constipation, fatigue, and somnolence were more common among ondansetron-treated participants (Fisher exact p < 0.05). Those who developed constipation were mostly rs1176713:GG carriers (Fisher exact p = 0.029).

CONCLUSIONS

Ondansetron did not demonstrate efficacy in the treatment of CUD. However, these preliminary results suggest a genotype-based variance in response to ondansetron in African ancestry individuals with CUD. Further studies are needed to validate findings for developing a personalized genomic approach for CUD treatment in racially and ethnically diverse populations.

Comparison of Treatments for Cocaine Use Disorder Among Adults: A Systematic Review and Meta-analysis

IMPORTANCE

In the US and the United Kingdom, cocaine use is the second leading cause of illicit drug overdose death. Psychosocial treatments for cocaine use disorder are limited, and no pharmacotherapy is approved for use in the US or Europe.

OBJECTIVE

To compare treatments for active cocaine use among adults.

DATA SOURCES

PubMed and the Cochrane Database of Systematic Reviews were searched for clinical trials published between December 31, 1995, and December 31, 2017.

STUDY SELECTION

This meta-analysis was registered on Covidence.org (study 8731) on December 31, 2015. Clinical trials were included if they (1) had the term cocaine in the article title; (2) were published between December 31, 1995, and December 31, 2017; (3) were written in English; (4) enrolled outpatients 18 years or older with active cocaine use at baseline; and (5) reported treatment group size, treatment duration, retention rates, and urinalysis results for the presence of cocaine metabolites. A study was excluded if (1) more than 25% of participants were not active cocaine users or more than 80% of participants had negative test results for the presence of cocaine metabolites at baseline and (2) it reported only pooled urinalysis results indicating the presence of multiple substances and did not report the specific proportion of positive test results for cocaine metabolites. Multiple reviewers reached criteria consensus. Of 831 records screened, 157 studies (18.9%) met selection criteria and were included in the analysis.

DATA EXTRACTION AND SYNTHESIS

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline. Search results were imported from PubMed XML into Covidence.org then Microsoft Excel. Data extraction was completed in 2 iterations to ensure fidelity. Analyses included a multilevel random-effects model, a multilevel mixed-effects meta-regression model, and sensitivity analyses. Treatments were clustered into 11 categories (psychotherapy, contingency management programs, placebo, opioids, psychostimulants, anticonvulsants, dopamine agonists, antidepressants, antipsychotics, miscellaneous medications, and other therapies). Missing data were imputed using multiple imputation by chained equations. The significance threshold for all analyses was P = .05. Data were analyzed using the metafor and mice packages in R software, version 3.3.2 (R Foundation for Statistical Computing). Data were analyzed from January 1, 2018, to February 28, 2021.

MAIN OUTCOMES AND MEASURES

The primary outcome was the intention-to-treat logarithm of the odds ratio (OR) of having a negative urinalysis result for the presence of cocaine metabolites at the end of each treatment period compared with baseline. The hypothesis, which was formulated after data collection, was that no treatment category would have a significant association with objective reductions in cocaine use.

RESULTS

A total of 157 studies comprising 402 treatment groups and 15 842 participants were included. Excluding other therapies, the largest treatment groups across all studies were psychotherapy (mean [SD] number of participants, 40.04 [36.88]) and contingency management programs (mean [SD] number of participants, 37.51 [25.51]). Only contingency management programs were significantly associated with an increased likelihood of having a negative test result for the presence of cocaine (OR, 2.13; 95% CI, 1.62-2.80), and this association remained significant in all sensitivity analyses.

CONCLUSIONS AND RELEVANCE

In this meta-analysis, contingency management programs were associated with reductions in cocaine use among adults. Research efforts and policies that align with this treatment modality may benefit those who actively use cocaine and attenuate societal burdens.

Open-label pilot study of lisdexamfetamine for cocaine use disorder

Background: Cocaine use disorder (CUD) is a substantial public health problem with no FDA-approved medication treatments. Psychostimulants have shown promise as pharmacotherapy for CUD. Lisdexamfetamine, a novel prodrug psychostimulant, is roughly 40-50% as potent as dextroamphetamine.Objectives: To evaluate the safety, tolerability, and optimal dosing of lisdexamfetamine for treating CUD.Methods: Open-label, 8-week trial of 17 CUD adults. Participants were titrated to the maximum tolerated dose of 140 mg over 2-week period and maintained for 4 weeks, followed by a two-week taper period. The primary outcome measures were the maximum daily dose achieved during the study period and tolerability as measured by medication-related study drop-out.Results: Among the 16 participants with post-enrollment data, the mean dose of lisdexamfetamine achieved was 118.1 mg (standard deviation (SD) = 40.4), mean retention was 6.5 weeks (SD = 2.0), and no participants discontinued study medication due to adverse effects. Four participants had dose reductions due to adverse effects and continued in the trial. Six participants (37.5%) were abstinent for the last 3 weeks of their study participation. Mean dollars of cocaine spent per day significantly decreased from $19.72 at baseline to $7.57 during the last 3 weeks of study participation (t₁₅ = 3.60, p = .003). The mean percent of using days significantly decreased from 25% at baseline to 12% during the last 3 weeks of study participation (t₁₅ = 3.33, p = .005).Conclusion: The use of lisdexamfetamine for CUD in doses ranging to 140 mg daily was safe and generally well tolerated.

Exploring the structural basis and atomistic binding mechanistic of the selective antagonist blockade at D3 dopamine receptor over D2 dopamine receptor

More recently, there has been a paradigm shift toward selective drug targeting in the treatment of neurological disorders, including drug addiction, schizophrenia, and Parkinson's disease mediated by the different dopamine receptor subtypes. Antagonists with higher selectivity for D₃ dopamine receptor (D3DR) over D₂ dopamine receptor (D2DR) have been shown to attenuate drug-seeking behavior and associated side effects compared to non-subtype selective antagonists. However, high conservations among constituent residues of both proteins, particularly at the ligand-binding pockets, remain a challenge to therapeutic drug design. Recent studies have reported the discovery of two small-molecules R-VK4-40 and Y-QA31 which substantially inhibited D3DR with >180-fold selectivity over D2DR. Therefore, in this study, we seek to provide molecular and structural insights into these differential binding mechanistic using meta-analytic computational simulation methods. Findings revealed that R-VK4-40 and Y-QA31 adopted shallow binding modes and were more surface-exposed at D3DR while on the contrary, they exhibited deep hydrophobic pocket binding at D2DR. Also, two non-conserved residues; Tyr36^1.39 and Ser182^45.51 were identified in D3DR, based on their crucial roles and contributions to the selective binding of R-VK4-40 and Y-QA31. Importantly, both antagonists exhibited high affinities in complex with D3DR compared to D2DR, while van der Waals energies contributed majorly to their binding and stability. Structural analyses also revealed the distinct stabilizing effects of both compounds on D3DR secondary architecture relative to D2DR. Therefore, findings herein pinpointed the origin and mechanistic of selectivity of the compounds, which may assist in the rational design of potential small molecules of the D₂ -like dopamine family receptor subtype with improved potency and selectivity.

Factors associated with the absence of cocaine craving in treatment-seeking individuals during inpatient cocaine detoxification

BACKGROUND

Anecdotal evidence suggests a substantial proportion of individuals with cocaine use disorder do not report craving during inpatient detoxification.

OBJECTIVE

To examine prevalence and clinical correlates of consistent absence of cocaine craving among inpatients during detoxification. We hypothesized that craving absence would be associated with less severity of cocaine use, depression, and anxiety. Alternative explanations were also explored.

METHODS

Craving absence (i.e., non-cravers) was defined as a daily score of zero across two separate craving visual analogue scales in each of the inpatient days. Participants scoring ≥1 on ≥1 day were considered cravers. Severity of cocaine use disorder as well as in-treatment depression and anxiety were assessed. Alternative contributors included presence of cocaine and other substances in urine at admission, in-treatment prescription of psychotropic medications, treatment motivation, executive function, interoception, and social desirability.

RESULTS

Eighty-seven participants (78.2% males) met criteria as either non-cravers (n = 29; 33.3%) or cravers (n = 58; 66.7%). Mean length of admission in non-cravers and cravers was, respectively, 10.83 and 13.16 days. Binary logistic regression model showed that non-cravers scored significantly lower than cravers on cocaine use during last month before treatment (OR, 95% CI; 0.902, 0.839-0.970), in-treatment depression (OR, 95% CI; 0.794, 0.659-0.956), and in-treatment prescribing of antipsychotics (OR, 95% CI; 0.109, 0.014-0.823). Model prediction accuracy was 88.9%.

CONCLUSIONS

One in three patients undergoing inpatient detoxification experienced absence of craving, linked to less pretreatment cocaine use, better mood, and decreased administration of antipsychotics. Findings may inform pretreatment strategies and improve treatment cost-effectiveness.

Cabergoline in Treatment of Methamphetamine-Dependent Patients and Its Effect on Serum Level of Glial Cell-Derived Neurotrophic Factor: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

BACKGROUND

Methamphetamine use disorder is an important public health problem, especially in the younger generation, and associated with various psychiatric, cognitive, social, economic, and legal issues. Cabergoline, a drug with dopaminergic properties and long half-life, has been considered for the treatment of stimulant dependence. The systemic use of cabergoline has been shown to increase glial cell-derived neurotrophic factor (GDNF) expression.

OBJECTIVE

In this study, we investigated the effects of cabergoline on the serum level of GDNF and its effect on abstaining from methamphetamine in individuals treated for methamphetamine use disorder.

METHOD

Sixty male subjects with methamphetamine use disorder were randomly assigned to 2 groups receiving cabergoline and placebo, respectively. During a 12-week follow-up, we compared the serum level of GDNF, urine test results for methamphetamine use, and depression scale between the 2 groups.

RESULTS

We found that serum GDNF was lower in subjects who used methamphetamine than healthy subjects (p < 0.0001). However, the serum level of GDNF was not associated with cabergoline use. The rising number of cases testing positive in the placebo group showed a trend resulting in no significant difference between cases testing positive and negative (p = 0.585) at the end of week 12. In the verum group, however, the significantly high number of cases who tested negative - sober - for substances observed in early stages (weeks 7-8) continued to remain significantly higher till the end of the study (p = 0.043), resembling an association between treatment with cabergoline and remaining sober. Although reduced during treatment, recovery from depression was not associated with cabergoline treatment.

CONCLUSION

The findings of this study confirmed the effect of cabergoline in reducing methamphetamine use. However, a serum level of the GDNF increase, as seen in animal studies, was not associated with cabergoline treatment of human subjects. This study was registered at the Iranian Registry of Clinical Trials (TRN:IRCT2015050422077N1, October 06, 2015, https://en.irct.ir/trial/19134).

Treatment of stimulant use disorder: A systematic review of reviews

AIMS

Stimulant use disorder contributes to a substantial worldwide burden of disease, although evidence-based treatment options are limited. This systematic review of reviews aims to: (i) synthesize the available evidence on both psychosocial and pharmacological interventions for the treatment of stimulant use disorder; (ii) identify the most effective therapies to guide clinical practice, and (iii) highlight gaps for future study.

METHODS

A systematic database search was conducted to identify systematic reviews and meta-analyses. Eligible studies were those that followed standard systematic review methodology and assessed randomized controlled trials focused on the efficacy of interventions for stimulant use disorder. Articles were critically appraised using an assessment tool adapted from Palmeteer et al. and categorized for quality as 'core' or 'supplementary' reviews. Evidence from the included reviews were further synthesized according to pharmacological or non-pharmacological management themes.

RESULTS

Of 476 identified records, 29 systematic reviews examining eleven intervention modalities were included. The interventions identified include: contingency management, cognitive behavioural therapy, acupuncture, antidepressants, dopamine agonists, antipsychotics, anticonvulsants, disulfiram, opioid agonists, N-Acetylcysteine, and psychostimulants. There was sufficient evidence to support the efficacy of contingency management programs for treatment of stimulant use disorder. Psychostimulants, n-acetylcysteine, opioid agonist therapy, disulfiram and antidepressant pharmacological interventions were found to have insufficient evidence to support or discount their use. Results of this review do not support the use of all other treatment options.

CONCLUSIONS

The results of this review supports the use of contingency management interventions for the treatment of stimulant use disorder. Although evidence to date is insufficient to support the clinical use of psychostimulants, our results demonstrate potential for future research in this area. Given the urgent need for effective pharmacological treatments for stimulant use disorder, high-quality primary research focused on the role of psychostimulant medications for the treatment of stimulant use disorder is needed.

Extended release mixed amphetamine salts and topiramate for cocaine dependence: A randomized clinical replication trial with frequent users

BACKGROUND

Cocaine use disorder (CUD) remains a substantial public health problem with no clearly effective pharmacotherapy available. In a prior trial, combined amphetamine and topiramate treatment significantly reduced cocaine use among individuals demonstrating the most frequent use at baseline. This trial targeted such frequent users.

METHODS

A double-blind, randomized placebo-controlled trial, testing the combination of mixed amphetamine salts extended-release (MAS-ER) and topiramate or placebo over a 12-week medication phase was conducted. The two-site outpatient trial included 127 adults (96 males) with CUD using at least 9 days in the prior month. MAS-ER was titrated to a maximum dose of 60 mg/day and topiramate to a maximum dose of 100 mg twice/day. The primary outcome was the proportion of individuals who achieved three consecutive abstinent weeks at the end of the study (EOS) as measured by urine toxicology and self-report.

RESULTS

The proportion of participants achieving three abstinent weeks at the EOS was significantly (P = .03) larger in the treatment (14.1%) compared to the placebo group (0.0%), while controlling for baseline cocaine use, sex, current alcohol use disorder, and site. Of note, due to conservative cardiac safety-parameters a considerable number of individuals in the treatment group were discontinued from study medication (20.3%).

CONCLUSIONS

While these findings provide further evidence that the combination of MAS-ER and topiramate is efficacious in promoting abstinence in CUD adults with frequent use it remains possible that the combination treatment is no more effective than either treatment alone. Despite this, the study provides a valuable "proof of concept."

Dopamine and addiction: what have we learned from 40 years of research

Among the neurotransmitters involved in addiction, dopamine (DA) is clearly the best known. The critical role of DA in addiction is supported by converging evidence that has been accumulated in the last 40 years. In the present review, first we describe the dopaminergic system in terms of connectivity, functioning and involvement in reward processes. Second, we describe the functional, structural, and molecular changes induced by drugs within the DA system in terms of neuronal activity, synaptic plasticity and transcriptional and molecular adaptations. Third, we describe how genetic mouse models have helped characterizing the role of DA in addiction. Fourth, we describe the involvement of the DA system in the vulnerability to addiction and the interesting case of addiction DA replacement therapy in Parkinson's disease. Finally, we describe how the DA system has been targeted to treat patients suffering from addiction and the result obtained in clinical settings and we discuss how these different lines of evidence have been instrumental in shaping our understanding of the physiopathology of drug addiction.

Evaluation of plasma cytokines in patients with cocaine use disorders in abstinence identifies transforming growth factor alpha (TGFα) as a potential biomarker of consumption and dual diagnosis

BACKGROUND

Cocaine use disorder (CUD) is a complex health condition, especially when it is accompanied by comorbid psychiatric disorders (dual diagnosis). Dual diagnosis is associated with difficulties in the stratification and treatment of patients. One of the major challenges in clinical practice of addiction psychiatry is the lack of objective biological markers that indicate the degree of consumption, severity of addiction, level of toxicity and response to treatment in patients with CUD. These potential biomarkers would be fundamental players in the diagnosis, stratification, prognosis and therapeutic orientation in addiction. Due to growing evidence of the involvement of the immune system in addiction and psychiatric disorders, we tested the hypothesis that patients with CUD in abstinence might have altered circulating levels of signaling proteins related to systemic inflammation.

METHODS

The study was designed as a cross-sectional study of CUD treatment-seeking patients. These patients were recruited from outpatient programs in the province of Malaga (Spain). The study was performed with a total of 160 white Caucasian subjects, who were divided into the following groups: patients diagnosed with CUD in abstinence (N = 79, cocaine group) and matched control subjects (N = 81, control group). Participants were clinically evaluated with the diagnostic interview PRISM according to the DSM-IV-TR, and blood samples were collected for the determination of chemokine C-C motif ligand 11 (CCL11, eotaxin-1), interferon gamma (IFNγ), interleukin-4 (IL-4), interleukin-8 (IL-8), interleukin-17α (IL-17α), macrophage inflammatory protein 1α (MIP-1α) and transforming growth factor α (TGFα) levels in the plasma. Clinical and biochemical data were analyzed in order to find relationships between variables.

RESULTS

While 57% of patients with CUD were diagnosed with dual diagnosis, approximately 73% of patients had other substance use disorders. Cocaine patients displayed greater cocaine symptom severity when they were diagnosed with psychiatric comorbidity. Regarding inflammatory factors, we observed significantly lower plasma levels of IL-17α (p < 0.001), MIP-1α (p < 0.001) and TGFα (p < 0.05) in the cocaine group compared with the levels in the control group. Finally, there was a significant primary effect of dual diagnosis on the plasma concentrations of TGFα (p < 0.05) in the cocaine group, and these levels were lower in patients with dual diagnoses.

DISCUSSION

IL-17α, MIP-1α and TGFα levels are different between the cocaine and control groups, and TGFα levels facilitate the identification of patients with dual diagnosis. Because TGFα reduction is associated with enhanced responses to cocaine in preclinical models, we propose TGFα as a potential biomarker of complex CUD in humans.

Synthesis and Pharmacological Characterization of Novel trans-Cyclopropylmethyl-Linked Bivalent Ligands That Exhibit Selectivity and Allosteric Pharmacology at the Dopamine D3 Receptor (D3R)

The development of bitopic ligands directed toward D₂-like receptors has proven to be of particular interest to improve the selectivity and/or affinity of these ligands and as an approach to modulate and bias their efficacies. The structural similarities between dopamine D₃ receptor (D₃R)-selective molecules that display bitopic or allosteric pharmacology and those that are simply competitive antagonists are subtle and intriguing. Herein we synthesized a series of molecules in which the primary and secondary pharmacophores were derived from the D₃R-selective antagonists SB269,652 (1) and SB277011A (2) whose structural similarity and pharmacological disparity provided the perfect templates for SAR investigation. Incorporating a trans-cyclopropylmethyl linker between pharmacophores and manipulating linker length resulted in the identification of two bivalent noncompetitive D₃R-selective antagonists, 18a and 25a, which further delineates SAR associated with allosterism at D₃R and provides leads toward novel drug development.

Risky and rushed public crack cocaine smoking: the potential for supervised inhalation facilities

BACKGROUND

Despite the multitude of public health and community harms associated with crack cocaine use, little is known about factors associated with smoking crack in public and related risks such as rushed public crack smoking.

METHODS

Data were derived from two prospective cohort studies of people who use illicit drugs in Vancouver, Canada between 2010 and 2014. Multivariable generalized estimating equations were used to identify the prevalence and correlates of public crack smoking and rushed public crack smoking.

RESULTS

In total, 1085 participants who had smoked crack in the prior six months were eligible for the analysis, of which 379 (34.9 %) reported always or usually smoking crack in public in the previous six months at some point during the study period. Factors positively and independently associated with public crack smoking included public injection drug use (adjusted odds ratio [AOR]: 5.42, 95 % confidence interval [CI]: 3.76-7.82), homelessness (AOR: 3.48, 95 % CI: 2.77-4.36), at least daily crack use (AOR: 2.69, 95 % CI: 2.19-3.31), crack pipe sharing (AOR: 1.98, 95 % CI: 1.60-2.46), drug dealing (AOR: 1.59, 95 % CI: 1.30-1.94), recent incarceration (AOR: 1.47, 95 % CI: 1.09-1.98), noticing police presence when buying or using drugs (AOR: 1.30, 95 % CI: 1.06-1.60), and younger age (AOR: 1.03, 95 % CI: 1.01-1.04). Rushed public crack smoking, which was reported by 216 (28.8 %) of 751 participants who had smoked crack in public at least once during the study period, was positively and independently associated with homelessness (AOR: 2.61, 95 % CI: 1.96-3.49), at least daily crack use (AOR: 1.48, 95 % CI: 1.11-1.98), crack pipe sharing (AOR: 1.44, 95 % CI: 1.10-1.89), drug dealing (AOR: 1.39, 95 % CI: 1.04-1.86), and younger age (AOR: 1.02, 95 % CI: 1.01-1.04).

CONCLUSIONS

A high prevalence of public crack smoking and rushed public crack smoking was observed in this setting. These findings point to the need for implementing and evaluating evidence-based public health interventions, such as supervised inhalation facilities, to reduce the risks and harms associated with smoking crack in public.

Individual variables related to craving reduction in cue exposure treatment

INTRODUCTION

Although extensive research has demonstrated that cigarette craving can be effectively attenuated, very few studies have explored associations between individual variables and craving reduction. This study explored whether individual characteristics predict craving decreases during virtual reality cue exposure treatment (VR-CET).

METHOD

Participants were 41 treatment-seeking smokers (73% women) with a mean age of 39.4 (SD=13.2), who had been smoking 15.0 (SD=7.1) cigarettes per day for 20.0 (SD=10.7) years. Their mean score on the Fagerström Test of Nicotine Dependence (FTND) was 4.8 (SD=2.3). Participants completed five cue exposure sessions using virtual reality for smoking cessation over a five-week period. The percentage of reduction in craving was calculated by comparing self-reported craving after the first and last exposure sessions. Sociodemographic characteristics (gender, age, years of education and marital status), tobacco-related [duration of daily smoking, cigarettes per day, FTND and Nicotine Dependence Syndrome Scale (NDSS)] and psychological characteristics [depressive symptoms (Beck's Depression Inventory-Second Edition, BDI-II), impulsiveness (delay discounting) and anxiety (State-Trait Anxiety Inventory, STAI)] were examined as possible predictors for craving reductions.

RESULTS

Multiple regression revealed that greater decreases in craving were associated with younger age (β=-.30, p=.043), cigarettes smoked per day (β=.30, p=.042), higher values on delay discounting (β=.34, p=.020) and higher BDI-II scores (β=.30, p=.035).

CONCLUSION

These findings suggest that smokers with certain individual characteristics may benefit most from interventions aimed at reducing craving through VR-CET.

Modafinil in the treatment of crack-cocaine dependence in the Netherlands: Results of an open-label randomised controlled feasibility trial

BACKGROUND

Crack-cocaine dependence is a serious disorder with no approved pharmacological treatment. Modafinil is a promising medication with increased cocaine abstinence and reduced craving in some previous studies. In the present study, we examined the acceptance, safety and potential benefits of modafinil as an add-on treatment to cognitive behavioural therapy (CBT) in crack-cocaine dependent patients.

METHODS

Sixty-five crack-cocaine dependent outpatients participated in an open-label, randomised feasibility trial. Patients were randomised to receive either 12-week individual CBT plus 400 mg/day modafinil or 12-week individual CBT only. The primary outcome measure was CBT treatment retention. Secondary outcomes included modafinil adherence, tolerability and safety, use of cocaine and other substances, cocaine craving, health, social functioning and patient satisfaction.

RESULTS

Modafinil adherence was low, with only 10% treatment completers. Intent-to-treat analyses showed that modafinil did not improve CBT treatment retention or any of the secondary cocaine-related outcomes. Both groups showed similar, large reductions in cocaine use during the study treatment. Post hoc exploratory analyses within the CBT plus modafinil group showed significantly larger baseline to week 12 reductions in cocaine use days in high (⩾ 8 weeks) modafinil adherent patients.

CONCLUSIONS

Acceptance and benefits of modafinil were not demonstrated in the present study. Since reduction in cocaine use was observed in high modafinil adherent patients, further research in the treatment of cocaine dependence, in which modafinil adherence is optimised, is warranted.

“Noids” in a nutshell: everything you (don’t) want to know about synthetic cannabimimetics

Purpose

– “Spice” products are synthetic cannabimimetics (SC; also called “synthetic cannabinoids”)-based designer drugs used as a legal alternative to cannabis for their very strong tetrahydrocannabinol (THC)-like effects. The purpose of this paper is to provide an analysis of more recent clinical and pharmacology/toxicology findings relating to SC and describe how they could impact on health, with a particular focus on mental health.

Design/methodology/approach

– A systematic search and descriptive analysis of the available evidence on psychopathological issues related to misuse was performed here, whilst taking into account the Pubmed/Medline databases, a range of conference proceedings and national/international agencies’ reports.

Findings

– While THC is a partial agonist, SC are full agonists on the cannabinoid receptors (CB-rs) and the administration of multiple SC can produce additive and/or synergistic agonistic interaction effects on the endocannabinoid system. These levels of strong CB-rs’ activation may be high enough to produce severe physiological and psychological disturbances. The available evidence suggests an existing relationship between SC use and psychosis (“Spiceophrenia”). The acute SC intoxication is usually characterized by tachycardia/hypertension; visual/auditory hallucinations; mydriasis; agitation/anxiety; tachypnoea; nausea/vomiting; and seizures.

Research limitations/implications

– The absence of clinical trials and longitudinal studies, together with the heterogeneity of SC compounds does not facilitate a precise assessment of the health risks related to their use, with long-term effects being of particular concern.

Originality/value

– Appropriate, non-judgemental, prevention campaigns with a special focus on the differences between SC and cannabis may need to be organized on a large scale. At the same time, clinicians need to be regularly updated about novel psychoactive substances, including SC, to promptly recognize signs/symptoms of intoxication.

Pharmacotherapeutics for substance-use disorders: a focus on dopaminergic medications

INTRODUCTION

Illicit substance-use is a substantial public health concern, contributing over $150 billion in costs annually to Americans. A complex disease, a substance-use disorder affects neural circuits involved in reinforcement, motivation, learning and memory, and inhibitory control.

AREAS COVERED

The modulatory influence of dopamine in mesocorticolimbic circuits contributes to encoding the primary reinforcing effects of substances and numerous studies suggest that aberrant signaling within these circuits contributes to the development of a substance-use disorder in some individuals. Decades of research focused on the clinical development of medications that directly target dopamine receptors has led to recent studies of agonist-like dopaminergic treatments for stimulant-use disorders and, more recently, cannabis-use disorder. Human studies evaluating the efficacy of dopaminergic agonist-like medications to reduce reinforcing effects and substance-use provide some insight into the design of future pharmacotherapy trials. A search of PubMed using specific brain regions, medications, and/or the terms 'dopamine', 'cognition', 'reinforcement', 'cocaine', 'methamphetamine', 'amphetamine', 'cannabis', 'treatment/pharmacotherapy', 'addiction/abuse/dependence' identified articles relevant to this review.

EXPERT OPINION

Conceptualization of substance-use disorders and their treatment continues to evolve. Current efforts increasingly focus on a strategy fostering combination pharmacotherapies that target multiple neurotransmitter systems.