Can antipsychotic treatment contribute to drug addiction in schizophrenia?

Knowledge and dispensing practice of community pharmacists towards antipsychotic medicines in a Nigerian metropolitan city - a cross-sectional study

BACKGROUND

Antipsychotic drugs are prescription-only-medications which require valid prescriptions before it can be obtained from a pharmacy. On the other hand, community pharmacists in developing countries have sometimes been implicated in over-the-counter dispensing of prescription-only-medications.

OBJECTIVE

This study investigated the accessibility of antipsychotic drugs without prescriptions from community pharmacies, and the factors responsible for the over-the-counter dispensing of antipsychotics by community pharmacists.

METHODS

An exploratory cross-sectional mixed method survey design using pretested structured questionnaires among 119 community pharmacists, simulated patients in 119 community pharmacies, and one-on-one in-depth interview among eleven (11) community pharmacist-owners/superintendent pharmacists were utilized for data collection. The knowledge of the pharmacists on antipsychotics including classification, side effects, and dispensing practices were explored. Qualitative data was analyzed with thematic analysis, while quantitative data was analyzed using descriptive statistics.

RESULTS

Majority of the community pharmacists (87.4%) showed good knowledge of antipsychotics as it relates to the different classes and the side effects peculiar to each class. Antipsychotic medications were dispensed by 85 (71.4%) of community pharmacists without a prescription. One-on-one in-depth interview sessions with community pharmacist owners/superintendent pharmacists demonstrated that community pharmacists are knowledgeable about antipsychotics and their side effects. Reasons given for dispensing this class of drugs without prescription included emergencies, and knowledge of the person as being on the drugs long-term. About 4% pharmacists were adamant on dispensing only with prescription.

CONCLUSION

Community pharmacists in Ibadan metropolis readily dispense antipsychotics without valid prescriptions despite having an optimal knowledge about the negative implications of doing so. This could be due to weak legislation and regulation of drug laws. There is a need for more stringent regulations as well as adequate sensitization about the negative effects of inappropriate dispensing of prescription-only-medications.

Brexpiprazole in patients with schizophrenia with or without substance use disorder: an observational study

Background

Partial dopamine D2 receptor agonists are used for psychotic symptoms in adults with schizophrenia spectrum disorders. Recently, interest surged for partial dopamine D2 receptor agonists in substance use disorders (SUDs). Since it is believed that SUDs decrease the efficacy of pharmacotherapy of underlying psychiatric disorders, we tested the efficacy of the partial D2 agonist brexpiprazole in patients with schizophrenia who were either comorbid with a SUD (SUD group) or not comorbid (non-SUD) to assess treatment response and the effect of brexpiprazole on substance craving in SUD.

Methods

We included patients with DSM-5/DSM-5-TR schizophrenia (using SCID-5-CV) aged 18-66 years with either comorbid SUD or non-SUD to treat with brexpiprazole 4 mg/day for 6 months during February-October 2022. Patients were assessed with the Clinical Global Impressions-Severity (CGI-S) scale, the 24-item Brief Psychiatric Rating Scale (BPRS), and the Positive And Negative Syndrome Scale (PANSS) at baseline, weekly for the first 2 months and monthly for the next four. Furthermore, we assessed substance craving in SUD with a visual analog scale for craving (VAScrav) at the same timepoints.

Results

The total sample was 86 (85 analysable) 18- to 64-year-old (mean 39.32 ± 14.09) patients with schizophrenia [51 men (59.3%) and 35 women (40.7%)], of whom 48 SUD (55.8%) (37 men and 11 women) and 38 non-SUD (44.2%) (14 men and 24 women). No serious or persistent adverse events developed over the study period, but one patient dropped out for subjective akathisia. Results indicated the main effects of time with improvements over the course of the study for CGI-S, BPRS, and PANSS in both SUD and non-SUD groups and the entire sample, and for VAScrav in SUD. Brexpiprazole was associated with similar significant improvements in both groups at the 6 month endpoint compared to baseline.

Conclusion

Treatment with brexpiprazole for 6 months improved psychotic symptoms in patients with schizophrenia, independently from whether they belonged to the SUD or the non-SUD group; hence, SUD comorbidity did not confer treatment resistance to brexpiprazole. Furthermore, in the SUD group, we observed reduced substance craving.

Worsening stimulant use disorder outcomes coinciding with off-label antipsychotic prescribing: a commonly unrecognised side effect?

Antipsychotic medications exert their effects via dopamine antagonism and are widely used off-label among persons with substance use disorders (SUD). While dopamine antagonists are recognised to stimulate food craving and weight gain, outside of possibly increasing nicotine craving and use, their impact on other SUD outcomes is poorly recognised. In this context, research has demonstrated that antipsychotic therapy can produce 'supersensitivity' to dopamine, enhancing the motivational effects of addictive drugs. Worsened drug craving and higher rates of substance use have also been observed in double-blind placebo-controlled trials. Nevertheless, widespread off-label antipsychotic prescribing among persons with SUD implies that the risks of worsening SUD outcomes are overall poorly recognised in both primary care and among specialists. We present a typical case of worsening stimulant use disorder in a patient prescribed antipsychotic medication for low mood and insomnia, highlighting that this is likely a widely under-recognised adverse effect of off-label antipsychotic therapy.

Antipsychotic Abuse, Dependence, and Withdrawal in the Pediatric Population: A Real-World Disproportionality Analysis

Antipsychotic drugs (APs) aim to treat schizophrenia, bipolar mania, and behavioral symptoms. In child psychiatry, despite limited evidence regarding their efficacy and safety, APs are increasingly subject to off-label use. Studies investigating addictology-related symptoms in young people being scarce, we aimed to characterize the different patterns of AP misuse and withdrawal in children and adolescents relying on the WHO pharmacovigilance database (VigiBase^®, Uppsala Monitoring Centre, Sweden). Using the standardized MedDRA Query 'drug abuse, dependence and withdrawal', disproportionality for each AP was assessed with the reporting odds ratio and the information component. A signal was detected when the lower end of the 95% confidence interval of the information component was positive. Results revealed mainly withdrawal symptoms in infants (under 2 years), intentional misuse in children (2 to 11 years), and abuse in adolescents (12 to 17 years). Olanzapine, risperidone, aripiprazole, and quetiapine were disproportionately reported in all age groups, with quetiapine being subject to a specific abuse signal in adolescents. Thus, in adolescents, the evocation of possible recreational consumption may lead to addiction-appropriate care. Further, in young patients with a history of AP treatment, a careful anamnesis may allow one to identify misuse and its role in the case of new-onset symptoms.

Long-acting second-generation and oral antipsychotics for substance use disorders and psychotic symptoms: Prescribing attitudes among Italian psychiatrists

PURPOSE

To explore Italian psychiatrists' attitudes toward the off-label use of second generation antipsychotics (SGAs) in patients with substance use disorder and psychotic symptoms.

DESIGN AND METHODS

A sample of 300 Italian psychiatrists associated with the Italian Society of Neuropsychopharmacology was randomly selected to complete a survey about the off-label prescription of SGAs.

FINDINGS

Oral aripiprazole (32.7%), olanzapine (30.2%), and quetiapine (25.2%) were considered "appropriate." Long-acting antipsychoticss were generally considered "inappropriate."

PRACTICE IMPLICATIONS

Our findings reflect a substantial level of uncertainty and a lack of coherent clinical guidance within the realm of dual diagnosis treatment. Therefore, they emphasize the need to develop specific guidelines to improve the management of pharmacotherapy among this population.

[Clinical presentations and therapy of polysubstance dependence in patients with schizophrenia]

BACKGROUND

The article presents the results of a clinical therapeutic and follow-up study of patients with a 'dual diagnosis' (polysubstance dependence comorbid with schizophrenia: paranoid schizophrenia or schizotypal disorder).

OBJECTIVE

To study clinical/dynamic changes of polysubstance dependence in patients with schizophrenia (paranoid schizophrenia, schizotypal disorder) and to evaluate the duration and quality of therapeutic remissions.

MATERIAL AND METHODS

Two hundred and sixty-six male patients, including 176 patients with dependence syndrome and 90 patients with both dependence syndrome and schizophrenia, were studied.

RESULTS

Patients with the 'dual diagnosis' are characterized by early social maladjustment, earlier social deformation, lack of social skills and preference for a lonely lifestyle. The clinical and dynamic characteristics of dependence syndrome in patients with 'dual diagnosis' include older age of the first use of a psychoactive substance (PS), preference of alcohol as the first PS, experiment as the most frequent motivation for using PS (due to thought disorder), and the treatment of psychopathological disorders (PS like medicine) with a chaotic pattern being the most common in the use, a tendency to hospitalism.

CONCLUSION

The success of the treatment of patients with 'dual diagnosis' is possible by combining the therapy of endogenous disease and polysubstance dependence.

Atypical antipsychotics in the treatment of patients with a dual diagnosis of schizophrenia spectrum disorders and substance use disorders: the results of a randomized comparative study

The article presents the results of a randomized comparative study of Aripiprazole and Quetiapine in the treatment of patients with a dual diagnosis: schizophrenia and substance use disorders. During the study, 90 of the 266 male patients were screened. Among them, 54 individuals (60%) had a previously established diagnosis of mental disorder and 36 patients (40%) had no established psychiatric diagnosis. They were randomly randomized into three groups of 30 patients, each receiving an antipsychotic: Aripiprazole at a dose of up to 20 mg daily, Quetiapine at a dose of up to 600 mg daily, or Haloperidol at a dose of up to 30 mg daily. The efficacy of Aripiprazole and Quetiapine was evaluated using the following scales: PANSS, BPRS, VAS, and Substance Craving Scale (SCS). Drug safety was assessed by the development of adverse events, serious adverse events, or adverse reactions. Study results demonstrated the efficacy of atypical antipsychotics in the three groups. Analysis of independent variables showed significant differences between Aripiprazole and Haloperidol in PANSS and BPRS scores by Visit 4, in VAS scores by Visit 3, and in SCS scores by Visit 2. Intergroup analysis of independent variables showed significant differences between Quetiapine and Haloperidol in PANSS, VAS, and SCS scores by Visit 4. Intergroup analysis of independent variables showed significant differences between Aripiprazole and Quetiapine in the VAS and SCS scores. The correlation analysis allowed drawing conclusions about the close connection of the symptoms of schizophrenia and substance use disorders in patients with a dual diagnosis.

Chronic risperidone administration leads to greater amphetamine-induced conditioned place preference

Risperidone is an atypical antipsychotic drug used increasingly in children to manage symptoms of ADHD and conduct disorder. In rats, developmental risperidone administration is accompanied by increased locomotor activity during adulthood, as well as heightened sensitivity to the locomotor stimulating effects of amphetamine. This study compared sensitivity to the rewarding effects of amphetamine, as measured by conditioned place preference (CPP), between groups of rats administered chronic risperidone (3.0 mg/kg, s.c.) during development (postnatal days 14-42) or adulthood (postnatal days 77-105). Locomotor activity in a novel test cage and amphetamine-induced CPP were measured beginning three and four weeks, respectively, after the final risperidone injection. Female rats administered risperidone early in life were more active than any other group tested. Previous risperidone administration enhanced amphetamine CPP regardless of sex, and this effect appeared more prominent in the developmentally treated group. The density of forebrain dopamine transporters, a primary target of amphetamine, was also quantified in rats administered risperidone early in life and found to be reduced in the medial anterior, posterior, and ventral caudate nucleus. These results suggest that chronic risperidone treatment modifies later locomotor activity and sensitivity to the reinforcing effects of amphetamine, perhaps via a mechanism related to decreased forebrain dopamine transporter density.

Differential Effect of Community Rehabilitation Reform on Hospitalizations of Patients with Chronic Psychotic Disorders With and Without Substance Use Disorder, Israel, 1991-2016

The co-occurrence of schizophrenia and substance use disorder (SUD) is clinically challenging and increasingly prevalent. This study compares trends in hospitalization characteristics of chronic psychotic patients with and without SUD in Israel, before and after introduction of the Community Rehabilitation of Persons with Mental Disability Law in 2000. The National Psychiatric Case Registry provided data on 18,684 adults with schizophrenia/schizoaffective disorders, hospitalized in 1991-2016 (at least once in 2010-2015). Repeated-measures ANOVA was used to measure the effect (and interactions) of group (patients with and without co-occurring disorders (COD)), time-period (Period₁: 1991-2000, Period₂: 2001-2009, Period₃: 2010-2016) and age, on hospitalization measures-average length of stay (LOS), annual number of hospitalizations and hospitalization days. Among non-COD patients hospitalized in all three periods, LOS declined by half from 133.3 days in Period₁ to 63.2 in Period₃, and the annual number of hospitalizations increased slightly from 0.45 to 0.56. Among COD patients, LOS declined moderately from 82.7 days to 58.3 days, while annual hospitalizations increased dramatically from 0.56 to 0.82. The annual average number of hospitalization days/capita declined from 49.7 in Period₁ to 26.3 in Period₃ among non-COD patients, yet remained virtually unchanged among COD patients-39.6 and 37.4 in the two periods, respectively. Since introduction of the law, a significant improvement in hospitalization characteristics of chronic psychotic non-COD patients has been noted, whereas the situation worsened somewhat for COD patients. Community rehabilitation services for COD patients in Israel have yet to develop as a suitable alternative to hospitalization, and additional rehabilitation services are urgently needed.

[Aripiprazole and quetiapine in the treatment of patients with 'dual diagnosis' of schizophrenia and drug addiction]

AIM

The randomized comparative study of aripiprazole and quetiapine in the treatment of patients with 'dual diagnosis' of schizophrenia and drug addiction.

MATERIAL AND METHODS

Intra-group analysis of dependent variables on the scales PANSS, BPRS, VAS, SACS showed significant differences in the dinamics of the therapy in all groups. A comparative randomized study included 90 men admitted to an inpatient addiction unit. Of these, 54 (60%) had a previously established psychiatric diagnosis and 36 patients (40%) did not have an established psychiatric diagnosis. They were randomized into 3 groups of 30 patients each: group 1 received aripiprazole at a dose of up to 20 mg/day, group 2 received quetiapine at a dose of up to 600 mg/day and group 3 (controls) was treated with haloperidol at a dose of up to 30 mg/day. Treatment duration was 21 days. The efficacy of aripiprazole and quetiapine was evaluated with PANSS, BPRS, VAS and SACS on 10^th, 14^th and 21^st day (visits 2-4). Drug safety was evaluated by recording adverse events or side-effects.

RESULTS AND CONCLUSION

An analysis of independent variables showed significant differences between aripiprazole and haloperidol in PANSS and BPRS scores at visit 4, in VAS scores at visit 3, and in SACS scores at visit 2. An intergroup analysis of independent variables showed significant differences between quetiapine and haloperidol in PANSS, VAS and SACS scores at visit 4 and between aripiprazole and quetiapine in VAS and SACS scores. According to the results of the correlation analisys it has been concluded that presenting features of schizophrenia are closely correlated with drug addiction (craving).

Dopamine D1 receptor antagonist reduces stimulant-induced conditioned place preferences and dopamine receptor supersensitivity

Repeated administration of stimulants induces conditioned place preference (CPP). Dopamine receptor supersensitivity is developed in stimulant-induced CPP animals; however, dopamine receptor subtypes associated with the development of supersensitivity in CPP animals are largely unknown. The present preclinical study aimed to examine whether dopamine D1 or D2 receptor antagonists exert inhibitory effects on stimulant-induced psychological behaviors. Additionally, the authors aimed to elucidate the role of dopamine receptor supersensitivity on the development of reward-related behavior. Sprague Dawley rats subjected to methamphetamine- and cocaine-induced CPP tests were treated with dopamine D1 (SCH23390) or D2 (sulpiride) receptor antagonists. Following the CPP experiment, rats were challenged with apomorphine (dopamine receptor agonist), and locomotor activity was measured. Methamphetamine- and cocaine-induced CPP was reduced with the administration of SCH23390, but not sulpiride. In addition, the apomorphine challenge evoked an increase in locomotor activity in stimulant-pre-treated rats, reflecting dopamine receptor supersensitivity. SCH23390 pre-treatment inhibited the development of dopamine receptor supersensitivity, while sulpiride demonstrated no inhibitory effects. These results suggest that the dopamine D1 receptor antagonist SCH23390 inhibits the development of dopamine receptor supersensitivity which is associated with the development of CPP.

Tobacco smoking is associated with antipsychotic medication, physical aggressiveness, and alcohol use disorder in schizophrenia: results from the FACE-SZ national cohort

Tobacco smoking is common in schizophrenia and is one of the main causes of premature mortality in this disorder. Little is known about clinical correlates and treatments associated with tobacco smoking in patients with schizophrenia. Still, a better characterization of these patients is necessary, in a personalized care approach. Aggressiveness and childhood trauma have been associated with tobacco smoking in general population, but this association has never been explored in schizophrenia. Our study examines the clinical and therapeutic characteristics of tobacco smoking in schizophrenia. 474 stabilized patients (mean age = 32.2; 75.7% male gender; smokers n = 207, 54.6%) were consecutively included in the network of the FondaMental Expert centers for Schizophrenia and assessed with valid scales. Current tobacco status was self-declared. Aggressiveness was self-reported with Buss-Perry Aggressiveness Questionnaire and Childhood Trauma with Childhood Trauma Questionnaire. Ongoing treatment was reported. In univariate analysis, tobacco smoking was associated with lower education level (p < 0.01), positive syndrome (p < 0.01), higher physical aggressiveness (p < 0.001), alcohol dependence (p < 0.001), and First Generation Antipsychotics (FGAs) use (p = 0.018). In a multivariate model, tobacco smoking remained associated with physical aggressiveness (p < 0.05), current alcohol dependence (p < 0.01) and FGA use (p < 0.05). No association was observed with childhood trauma history, mood disorder, suicidal behavior, psychotic symptom, global functioning or medication adherence. Patients with tobacco use present clinical and therapeutic specificities, questioning the neurobiological links between tobacco and schizophrenia. They could represent a specific phenotype, with specific clinical and therapeutic specificities that may involve interactions between cholinergic-nicotinic system and dopaminergic system. Further longitudinal studies are needed to confirm the potential efficacy of second generation antipsychotics (SGAs) on tobacco use in schizophrenia and to develop effective strategies for tobacco cessation in this population.

Revisiting the Concept of Subjective Tolerability to Antipsychotic Medications in Schizophrenia and its Clinical and Research Implications: 30 Years Later

Schizophrenia is a long-term psychiatric disorder that impacts important mental functions and requires indefinite treatment, as well as psychosocial and economic support. The introduction of chlorpromazine, the first antipsychotic, and the subsequent development of a long list of similar dopamine-blocking antipsychotic medications, has changed the treatment of schizophrenia as medications have become the cornerstone of clinical management. The enthusiasm that greeted the introduction of antipsychotics was soon tempered by the realisation that they induced significant side effects, such as extrapyramidal and autonomic symptoms. A less-recognized side effect at the time was the emergence of subtle subjective side effects that led patients to dislike medications and eventually discontinue them, with serious consequences of frequent relapses requiring hospitalization, poor outcomes and more health costs. The development of our dedicated programme for research into subjective tolerability to medications over the past 30 years has allowed us to establish the validity of the construct of 'subjective tolerability' to antipsychotics, applying research methodologies that are required for any scientific inquiry. We clarified definitions, developed reliable measuring tools, and constructed psychosocial and neurobiological conceptual models. We also documented the serious consequences of negative subjective tolerability to antipsychotics: poor medication adherence behaviour, impaired quality of life, and worse clinical and functional outcomes. More recently, using neuroimaging techniques, we and other international research groups were able to clearly elucidate the neurobiology of dysphoric negative subjective responses, linking it to low dopamine functioning in the striatal region of the brain. Such a discovery for the first time allowed us to also link the development of comorbid drug abuse in schizophrenia, which is a common occurrence, to the development of neuroleptic dysphoria, since both relate to the low dopamine function in the striatum. As an already validated scientific concept that has serious consequences, subjective tolerability to antipsychotics can serve as a model for patient-centered outcomes that really matter. Our long-serving research programme also illustrates the value of clinical observations to the development of important clinical research studies, i.e. from the bedside to the research bench, and back to the bedside.

[Aripiprazole as dopamine partial agonist model: Basic concepts and clinical impact]

Aripiprazole may be viewed as the prototype of third-generation antipsychotics. This concept is based on the notion of D2 partial agonism, whereas all molecules of first-and second generation were D2 antagonists. After reviewing the basic pharmacological notions linked to such concepts, the mechanisms of action of these molecules are addressed, with a particular focus on functional selectivity and biased ligand. One of the essential pharmacological properties of D2 agonists, and particularity aripiprazole, is their ability to not induce D2 supersensitivity as well as to reverse this supersensitivity when it has been induced by D2 antagonists. In clinical practice, this impacts the choice of treatment in first episode psychosis as well as in refractory schizophrenia. Animal research shows that D2 supersensitivity could contribute to worsen addictive trends. The pharmacokinetic incidence of D2 supersensitivity tends to favour the long-acting forms of partial agonists. The notion of partial agonism could finally lead to design fourth-generation antipsychotics, on the basis on research focusing on functional selectivity.

Antipsychotic-Induced Dopamine Supersensitivity Psychosis: Pharmacology, Criteria, and Therapy

The first-line treatment for psychotic disorders remains antipsychotic drugs with receptor antagonist properties at D2-like dopamine receptors. However, long-term administration of antipsychotics can upregulate D2 receptors and produce receptor supersensitivity manifested by behavioral supersensitivity to dopamine stimulation in animals, and movement disorders and supersensitivity psychosis (SP) in patients. Antipsychotic-induced SP was first described as the emergence of psychotic symptoms with tardive dyskinesia (TD) and a fall in prolactin levels following drug discontinuation. In the era of first-generation antipsychotics, 4 clinical features characterized drug-induced SP: rapid relapse after drug discontinuation/dose reduction/switch of antipsychotics, tolerance to previously observed therapeutic effects, co-occurring TD, and psychotic exacerbation by life stressors. We review 3 recent studies on the prevalence rates of SP, and the link to treatment resistance and psychotic relapse in the era of second-generation antipsychotics (risperidone, paliperidone, perospirone, and long-acting injectable risperidone, olanzapine, quetiapine, and aripiprazole). These studies show that the prevalence rates of SP remain high in schizophrenia (30%) and higher (70%) in treatment-resistant schizophrenia. We then present neurobehavioral findings on antipsychotic-induced supersensitivity to dopamine from animal studies. Next, we propose criteria for SP, which describe psychotic symptoms and co-occurring movement disorders more precisely. Detection of mild/borderline drug-induced movement disorders permits early recognition of overblockade of D2 receptors, responsible for SP and TD. Finally, we describe 3 antipsychotic withdrawal syndromes, similar to those seen with other CNS drugs, and we propose approaches to treat, potentially prevent, or temporarily manage SP.

Patterns of Management of Patients With Dual Disorder (Psychosis) in Italy: A Survey of Psychiatrists and Other Physicians Focusing on Clinical Practice

Patients with severe psychotic disorders such as schizophrenia, schizoaffective, and bipolar disorders frequently suffer from concomitant substance use disorders (SUDs)-Dual Disorder (DD) patients. In order to better understand current practices for management of patients with psychotic episodes and concomitant SUD in Italy, we carried out a survey of psychiatrists on current routine practice among prescribers. These aspects can help to identify at-risk patients, improve current prescribing practices, and favor early intervention. An ad hoc survey of 17 questions was administered to psychiatrists via electronic polling and on-line distribution; 448 completed questionnaires were collected. Comorbid substance abuse was most frequently diagnosed within the context of anxiety disorder (46%), followed by bipolar disorder (25%), and schizophrenia/schizoaffective disorder (12%). The vast majority of respondents felt that patient management was becoming more complex due to substance abuse. The areas reported to be most affected in patients with SUD were functioning, interpersonal relations, and impulsivity, while sensory perception disorders, ideation, agitation, and impulsivity were the most frequently reported symptoms. In the acute setting, haloperidol was used as the first-line agent of choice followed by aripiprazole and olanzapine. In the maintenance phase, aripiprazole was the dominantly used first-line agent, followed by olanzapine. Almost half of respondents used long-acting agents, while about one-third did not. Among those prescribing long-acting agents, efficacy, control of impulsivity, and control of specific symptoms were cited as motivators, while in the maintenance phase, better adherence, and tolerability were mainly cited. From the responses to the present survey, it is clear that the respondents are aware of the problem of SUD in psychotic patients. While treatment be optimized in terms of the choice and formulation of antipsychotics, greater emphasis should be placed on efficacy, tolerability, and the negative metabolic consequences of some antipsychotics. When considering the ideal antipsychotic, long-acting agents were considered to be superior in reducing relapse, even if current treatment guidelines often give preference to oral formulations.

Antipsychotic Drugs: From Receptor-binding Profiles to Metabolic Side Effects

BACKGROUND

Antipsychotic-induced metabolic side effects are major concerns in psychopharmacology and clinical psychiatry. Their pathogenetic mechanisms are still not elucidated.

METHODS

Herein, we review the impact of neurotransmitters on metabolic regulation, providing insights into antipsychotic-induced metabolic side effects.

RESULTS

Antipsychotic drugs seem to interfere with feeding behaviors and energy balance, processes that control metabolic regulation. Reward and energy balance centers in central nervous system constitute the central level of metabolic regulation. The peripheral level consists of skeletal muscles, the liver, the pancreas, the adipose tissue and neuroendocrine connections. Neurotransmitter receptors have crucial roles in metabolic regulation and they are also targets of antipsychotic drugs. Interaction of antipsychotics with neurotransmitters could have both protective and harmful effects on metabolism.

CONCLUSION

Emerging evidence suggests that antipsychotics have different liabilities to induce obesity, diabetes and dyslipidemia. However this diversity cannot be explained merely by drugs'pharmacodynamic profiles, highlighting the need for further research.

Cigarette smoking and schizophrenia: a specific clinical and therapeutic profile? Results from the FACE-Schizophrenia cohort

BACKGROUND

Tobacco use is common in patients with schizophrenia (SZ) but little is known on the role of tobacco in the physiopathology or on the course of the disease. Only few studies embrace an extensive examination of clinical and therapeutic characteristics in stabilized patients. The objective of the present study was to determine the prevalence of tobacco smoking in stabilized SZ outpatients and the clinical and treatment characteristics associated with daily tobacco use in a large community-dwelling sample of patients.

METHODS

Three-hundred-and-sixty-one patients were included in the network of the FondaMental Expert Centers for Schizophrenia. Current tobacco status was self-declared.

RESULTS

53.7% were smokers. Mean age at tobacco onset was 17.2years old. In multivariate analyses, after adjustment for confounding factors, positive symptoms and mean daily antipsychotic dose were associated with a higher frequency of tobacco use (OR=1.06 95%IC[1.02-1.12], for positive symptoms, OR=1.1, 95%IC[1.02-1.18] for daily antipsychotic dose). Education level, negative symptoms, anticholinergic agents, clozapine or aripiprazole administration were independently associated with a lower frequency of tobacco use (respectively OR=0.87, 95%IC [0.79, 0.95], OR=0.95, 95%IC[0.91-0.98], OR=0.41, 95%IC[0.22-0.76], OR=0.56, 95%IC=[0.32, 0.99] and OR=0.49, 95%IC [0.26-0.91]).

CONCLUSION

The prevalence of current tobacco smoking in a French community-dwelling SZ patients is higher that observed in the general population. Patients with tobacco use present clinical and therapeutic specificities that may involve interaction between cholinergic-nicotinic and dopaminergic systems. The present study suggests that some therapeutics may improve daily smoking behavior in smokers. These results should be confirmed in longitudinal studies.

Reactivity to addictive drugs in the methylazoxymethanol (MAM) model of schizophrenia in male and female rats

OBJECTIVES

Patients with schizophrenia often suffer comorbid substance abuse regardless of gender. However, the vast majority of studies are only conducted in male subjects. Therefore, the aim of these experiments is to assess addictive behaviors of both sexes in a neurodevelopmental model of schizophrenia induced by prenatal methylazoxymethanol (MAM) acetate exposure.

METHODS

MAM (22 mg/kg) was administered intraperitoneally on gestational day 17. Two studies were performed in the offspring: (1) an alcohol-drinking procedure to assess daily intake of 20% alcohol and relapse-like behavior after a period of forced abstinence; (2) Methamphetamine (METH) intravenous self administration (IVSA) followed by forced abstinence and reinstatement phases.

RESULTS

MAM exposure during the prenatal period did not change alcohol drinking regardless of sex. However, MAM females showed higher alcohol consumption in comparison to MAM males. The METH IVSA study revealed only a modest increase of drug consumption in MAM males, while there was no difference between the female groups. Reinstatement data showed no effect of the MAM model in either sex, but suggested increased responding in female rats.

CONCLUSIONS

This study suggests that female sex and schizophrenia-like phenotype may work synergistically to enhance alcohol consumption. However, future research is needed to establish paradigms in which these findings would be readily assessed to test anti-addiction treatments.

Etiological theories of addiction: A comprehensive update on neurobiological, genetic and behavioural vulnerability

Currently, about 246 million people around the world have used an illicit drug. The reasons for this use are multiple: e.g. to augment the sensation of pleasure or to reduce the withdrawal and other aversive effects of a given substance. This raises the problem of addiction, which remains a disease of modern society. This review offers a comprehensive update of the different theories about the etiology of addictive behaviors with emphasis on the neurobiological, environmental, psychopathological, behavioural and genetic aspects of addictions, discussed from an evolutionary perspective. The main conclusion of this review is that vulnerability to drug addiction suggests an interaction between many brain systems (including the reward, decision-making, serotonergic, oxytocin, interoceptive insula, CRF, norepinephrine, dynorphin/KOR, orexin and vasopressin systems), genetic predisposition, sociocultural context, impulsivity and drugs types. Further advances in biological and psychological science are needed to address the problems of addiction at its roots.

High estrogen and chronic haloperidol lead to greater amphetamine-induced BOLD activation in awake, amphetamine-sensitized female rats

The ovarian hormone estrogen has been implicated in schizophrenia symptomatology. Low levels of estrogen are associated with an increase in symptom severity, while exogenous estrogen increases the efficacy of antipsychotic medication, pointing at a possible interaction between estrogen and the dopaminergic system. The aim of this study is to further investigate this interaction in an animal model of some aspects of schizophrenia using awake functional magnetic resonance imaging. Animals receiving 17β-estradiol and haloperidol were scanned and BOLD activity was assessed in response to amphetamine. High 17β-estradiol replacement and chronic haloperidol treatment showed increased BOLD activity in regions of interest and neural networks associated with schizophrenia (hippocampal formations, habenula, amygdala, hypothalamus etc.), compared with low, or no 17β-estradiol. These data show that chronic haloperidol treatment has a sensitizing effect, possibly on the dopaminergic system, and this effect is dependent on hormonal status, with high 17β-estradiol showing the greatest BOLD increase. Furthermore, these experiments further support the use of imaging techniques in studying schizophrenia, as modeled in the rat, but can be extended to addiction and other disorders.

Revisiting the 'self-medication' hypothesis in light of the new data linking low striatal dopamine to comorbid addictive behavior

Persons with schizophrenia are at a high risk, almost 4.6 times more likely, of having drug abuse problems than persons without psychiatric illness. Among the influential proposals to explain such a high comorbidity rate, the 'self-medication hypothesis' proposed that persons with schizophrenia take to drugs in an effort to cope with the illness and medication side effects. In support of the self-medication hypothesis, data from our earlier clinical study confirmed the strong association between neuroleptic dysphoria and negative subjective responses and comorbid drug abuse. Though dopamine has been consistently suspected as one of the major culprits for the development of neuroleptic dysphoria, it is only recently our neuroimaging studies correlated the emergence of neuroleptic dysphoria to the low level of striatal dopamine functioning. Similarly, more evidence has recently emerged linking low striatal dopamine with the development of vulnerability for drug addictive states in schizophrenia. The convergence of evidence from both the dysphoria and comorbidity research, implicating the role of low striatal dopamine in both conditions, has led us to propose that the person with schizophrenia who develops dysphoria and comorbid addictive disorder is likely to be one and the same.

Evaluation of the individual safe correction of antipsychotic agent polypharmacy in Japanese patients with chronic schizophrenia: validation of safe corrections for antipsychotic polypharmacy and the high-dose method

BACKGROUND

Polypharmacy for schizophrenia treatment is not justified by the available clinical evidence. We evaluated a treatment reduction approach that reduces the dose and number of antipsychotic medications simultaneously prescribed to patients.

METHODS

In a randomized open study of the Safe Correction of Antipsychotic Polypharmacy and High-Dose Prescriptions program funded by the Japanese Ministry of Health, Labour, and Welfare, we evaluated a drug reduction method consisting of a dose reduction intervention performed on 163 patients with schizophrenia for twelve or 24 weeks. One antipsychotic medication was removed each week from each patient's treatment regimen by reducing the dose by 0 to 50 chlorpromazine equivalents. Data on health-related indices of quality of life, clinical symptoms, and risk of side effects were analyzed using a two-way repeated-measures mixed linear model.

RESULTS

Despite a 23% reduction in antipsychotic dose, no differences in outcomes were observed between the dose reduction and observation groups (effect size = 0.001 - 0.085, P = .24-.97), despite high statistical power (1-β = 0.48-0.97). The findings are limited by the nonuniformity of the participants' treatment history, duration, and dose reduction amount. Dose reduction protocol patients exhibited no difference in psychotic symptoms or adverse events compared with the observation group.

CONCLUSIONS

Importantly, the low dropout rate in our study (6.9% of participants withdrew because of patient factors and 23.8% for all secondary reasons) indicates that our "slowly" method is well tolerated. We hope that this approach will result in therapeutic improvements.

Canadian Orofacial Pain Team workshop report on the global year against orofacial pain

The year 2013-2014 has been designated the Global Year Against Orofacial Pain by the International Association for the Study of Pain. Accordingly, a multidisciplinary Canadian and international group of clinical, research and knowledge-transfer experts attended a workshop in Montreal, Quebec. The workshop had two aims: to identify new pathways for innovative diagnosis and management of chronic orofacial pain states; and to identify opportunities for further collaborative orofacial pain research and education in Canada. Three topics related to chronic orofacial pain were explored: biomarkers and pain signatures for chronic orofacial pain; misuse of analgesic and opioid pain medications for managing chronic orofacial pain; and complementary alternative medicine, topical agents and the role of stress in chronic orofacial pain. It was determined that further research is needed to: identify biomarkers of chronic orofacial post-traumatic neuropathic pain, with a focus on psychosocial, physiological and chemical-genetic factors; validate the short- and long-term safety (i.e., no harm to health, and avoidance of misuse and addiction) of opioid use for two distinct conditions (acute and chronic orofacial pain, respectively); and promote the use of topical medications as an alternative treatment in dentistry, and further document the benefits and safety of complementary and alternative medicine, including stress management, in dentistry. It was proposed that burning mouth syndrome, a painful condition that is not uncommon and affects mainly postmenopausal women, should receive particular attention.

Pharmacotherapy of Co-Occurring Schizophrenia and Substance Use Disorders

Substance use disorders, common in patients with schizophrenia, can lead to poor outcomes. Here we review the literature on the use of antipsychotics in patients with co-occurring schizophrenia and substance use disorder as well as evidence for the use of adjunctive pharmacological treatments targeting substance use in these patients. We also discuss a neurobiological formulation suggesting that the cooccurrence of these disorders may be related to a dysfunction in the dopamine mediated brain reward circuitry. Typical antipsychotics do not appear to decrease substance use in this population. Randomized, controlled trials provide some support for use of the atypical antipsychotic clozapine for co-occurring cannabis use disorder, naltrexone and disulfiram for alcohol use disorder, and also nicotine replacement therapy, sustained-release bupropion and varenicline for tobacco use disorder. Nonetheless, data regarding treatment in patients with these co-occurring disorders are still limited, and many studies reported to date have been either underpowered or did not include a control condition. Further research is needed to evaluate optimal pharmacotherapeutic strategies for this population.

Do reward-processing deficits in schizophrenia-spectrum disorders promote cannabis use? An investigation of physiological response to natural rewards and drug cues

BACKGROUND

Dysfunctional reward processing is present in individuals with schizophrenia-spectrum disorders (SSD) and may confer vulnerability to addiction. Our objective was to identify a deficit in patients with SSD on response to rewarding stimuli and determine whether this deficit predicts cannabis use.

METHODS

We divided a group of patients with SSD and nonpsychotic controls into cannabis users and nonusers. Response to emotional and cannabis-associated visual stimuli was assessed using self-report, event-related potentials (using the late positive potential [LPP]), facial electromyography and skin-conductance response.

RESULTS

Our sample comprised 35 patients with SSD and 35 nonpsychotic controls. Compared with controls, the patients with SSD showed blunted LPP response to pleasant stimuli (p = 0.003). Across measures, cannabis-using controls showed greater response to pleasant stimuli than to cannabis stimuli whereas cannabis-using patients showed little bias toward pleasant stimuli. Reduced LPP response to pleasant stimuli was predictive of more frequent subsequent cannabis use (β = -0.24, p = 0.034).

LIMITATIONS

It is not clear if the deficit associated with cannabis use is specific to rewarding stimuli or nonspecific to any kind of emotionally salient stimuli.

CONCLUSION

The LPP captures a reward-processing deficit in patients with SSD and shows potential as a biomarker for identifying patients at risk of heavy cannabis use.

Is schizophrenia a dopamine supersensitivity psychotic reaction?

Adolf Meyer (1866-1950) did not see schizophrenia as a discrete disorder with a specific etiology but, rather, as a reaction to a wide variety of biopsychosocial factors. He may have been right. Today, we have evidence that gene mutations, brain injury, drug use (cocaine, amphetamine, marijuana, phencyclidine, and steroids), prenatal infection and malnutrition, social isolation and marginalization, can all result in the signs and symptoms of schizophrenia. This clinical picture is generally associated with supersensitivity to dopamine, and activates dopamine neurotransmission that is usually alleviated or blocked by drugs that block dopamine D2 receptors. While the dopamine neural pathway may be a final common route to many of the clinical symptoms, the components of this pathway, such as dopamine release and number of D2 receptors, are approximately normal in schizophrenia patients who are in remission. Postmortem findings, however, reveal more dimers of D1D2 and D2D2 receptors in both human schizophrenia brains and in animal models of schizophrenia. Another finding in animal models is an elevation of high-affinity state D2High receptors, but no radioactive ligand is yet available to selectively label D2High receptors in humans. It is suggested that synaptic dopamine supersensitivity in schizophrenia is an attempt at compensation for the original damage by heightening dopamine neurotransmission pathways (preparing the organism for fight or flight). The dopamine overactivity is experienced subjectively as overstimulation, which accounts for some of the clinical symptoms, with attempts at dampening down the stimulation leading to still other symptoms. Reaction and counter-reaction may explain the symptoms of schizophrenia.