The link between schizophrenia and substance use disorder: A unifying hypothesis

Low Psychological Resilience Predict the Risk for Alcohol Use Disorder in General Population: National Mental Health Survey of Korea 2021

Objective

Prior research has emphasized psychological resilience as a potential protective factor against alcohol use disorder in diverse populations, with limited exploration of its relationship in the general population. This study investigated the association between the lifetime and one-year prevalence of alcohol use disorder and resilience.

Methods

Data obtained from the National Mental Health Survey of Korea 2021 (5,511 participants; 40.7% response rate) encompassed information on alcohol use disorders, resilience, experiences of psychological trauma, and major mental disorders. The analyses compared demographics, psychological trauma, resilience, and the prevalence of major mental disorders based on alcoholism. The contribution of resilience to alcoholism was assessed utilizing Rao-Scott logistic regression, with adjustments made for confounding variables.

Results

Individuals with both lifetime and 1-year alcohol use disorder and dependence exhibited significantly lower levels of resilience on the Connor-Davidson Resilience Scale. Diminished resilience predicted morbidity and persisted even after adjusting for depressive and anxiety disorders, psychological trauma, nicotine use disorders, age, gender, education, income, marital status, and occupation.

Conclusion

Diminished resilience is a prognostic indicator of increased likelihood of both lifetime and current alcoholism in the general population.

Emergency Department Visits Involving Hallucinogen Use and Risk of Schizophrenia Spectrum Disorder

Importance

Interest in and use of hallucinogens has been increasing rapidly. While a frequently raised concern is that hallucinogens may be associated with an increased risk of psychosis, there are limited data on this association.

Objectives

To examine whether individuals with an emergency department (ED) visit involving hallucinogen use have an increased risk of developing a schizophrenia spectrum disorder (SSD).

Design, Settings, and Participants

This population-based, retrospective cohort study (January 2008 to December 2021) included all individuals aged 14 to 65 years in Ontario, Canada, with no history of psychosis (SSD or substance induced). Data were analyzed from May to August 2024.

Exposure

An incident ED visit involving hallucinogen use.

Main Outcomes and Measures

Diagnosis of SSD using a medical record-validated algorithm. Associations between ED visits involving hallucinogens and SSD were estimated using cause-specific adjusted hazard models. Individuals with an incident ED visit involving hallucinogens were compared with members of the general population (primary analysis) or individuals with ED visits involving alcohol or cannabis (secondary analysis).

Results

The study included 9 244 292 individuals (mean [SD] age, 40.4 [14.7] years; 50.2% female) without a history of psychosis, with a median follow-up of 5.1 years (IQR, 2.3-8.6 years); 5217 (0.1%) had an incident ED visit involving hallucinogen use. Annual rates of incident ED visits involving hallucinogens were stable between 2008 and 2012 and then increased by 86.4% between 2013 and 2021 (3.4 vs 6.4 per 100 000 individuals). Individuals with ED visits involving hallucinogens had a greater risk of being diagnosed with an SSD within 3 years compared with the general population (age- and sex-adjusted hazard ratio [HR], 21.32 [95% CI, 18.58-24.47]; absolute proportion with SSD at 3 years, 208 of 5217 with hallucinogen use [3.99%] vs 13 639 of 9 239 075 in the general population [0.15%]). After adjustment for comorbid substance use and mental health conditions, individuals with hallucinogen ED visits had a greater risk of SSD compared with the general population (HR, 3.53; 95% CI, 3.05-4.09). Emergency department visits involving hallucinogens were associated with an increased risk of SSD within 3 years compared with ED visits involving alcohol (HR, 4.66; 95% CI, 3.82-5.68) and cannabis (HR, 1.47; 95% CI, 1.21-1.80) in the fully adjusted model.

Conclusions and Relevance

In this cohort study, individuals with an ED visit involving hallucinogen use had a greater risk of developing an SSD compared with both the general population and with individuals with ED visits for other types of substances. These findings have important clinical and policy implications given the increasing use of hallucinogens and associated ED visits.

Factors of Engagement in Employment or Education Following a First Episode of Psychosis: A Systematic Review and Narrative Synthesis

Despite 75% of people who experience a first episode of psychosis (FEP) reaching clinical remission, this population continue to face lower rates of vocational recovery. This review aimed to identify the factors which help and hinder individuals' employment and post-secondary education engagement post-FEP. Three electronic databases (Psych INFO, Medline and Social Science Database) were searched up to 21st August 2023. Primary research on employment/education status or engagement within FEP populations ages 18-40 were included. A narrative synthesis was applied to the findings. Of the 10,575 articles screened, 18 were included in the final review. Younger age, non-affective psychotic diagnoses and stigma were identified as common barriers to engagement. Ceasing substance use and having family/financial support were reported as facilitators. Conflicting findings were reported as to the impact of positive and negative symptoms. The range of factors emerging from this review highlight several potential barriers and facilitators for individuals seeking employment or further education opportunities post-FEP. This underlines the need for further research into how and why they influence employment and educational outcomes, with a view to improving treatment outcomes by incorporating these factors into care planning.

Social defeat predicts the emergence of psychotic-like experiences through the effects on aberrant salience: insights from a network analysis of longitudinal data

BACKGROUND

Psychotic-like experiences (PLEs) are subclinical phenomena that often precede the onset of psychosis and occur in various mental disorders. Social determinants of psychosis and PLEs are important and have been operationalized within the social defeat (SD) hypothesis. The SD hypothesis posits that low social status and exposure to repeated humiliation can lead to imbalanced dopamine neuron activity, and thus increased risk of psychosis. We aimed to assess the role of dynamic interactions between SD components in shaping the occurrence of PLEs using a network analysis.

METHODS

A total of 2241 non-clinical, young adults were assessed at baseline and invited for reassessment after a 6-month follow-up. Self-reports recording the occurrence of PLEs, aberrant salience (AS), depressive, and anxiety symptoms as well as SD characteristics (socioeconomic status, minority status, humiliation, perceived constraints, and domain control) were administered. Two networks were analyzed (the first one covering all baseline measures and the second one with the baseline SD components and follow-up measures of AS and psychopathology).

RESULTS

The SD components were not directly connected to the measures of PLEs in both networks. However, in both networks, SD components were connected to PLEs through a mediating effect of AS. Among SD components, humiliation had the highest bridge centrality across three predefined communities of variables (SD; depressive and anxiety symptoms; AS, and PLEs).

CONCLUSIONS

The findings indicate that SD might make individuals vulnerable to develop PLEs through the mediating effects of AS. Among SD components, humiliation might play the most important role in the development of PLEs.

Behavioral Test Scores Could Be Linked to the Protein Expression Values of p62 and GLAST in the Brains of Mice with Neuropsychiatric Disorder-Related Behaviors

Neuropsychiatric disorders are a public health concern, in which diagnosis and prognosis may be based on clinical symptoms that might often diverge across individuals. Schizophrenia is a major neuropsychiatric disorder, which may affect millions worldwide. However, the biochemical alterations of this disorder have not been comprehensively distinguished. In addition, there is less confidence in finding specific biomarkers for neuropsychiatric disorders, including schizophrenia, but rather a specific characteristic behavioral pattern. In general, maternal immune activation is considered to be one of the important factors in the development of neuropsychiatric disorders. Here, a mouse model of neuropsychiatric disorders was created, in which poly I:C, sodium dextran sulfate (DSS), and κ-carrageenan (CGN) were utilized for maternal immune activation during the pregnancies of mother mice. Subsequently, we examined the link between biochemical changes in p62 and/or glutamate aspartate transporter (GLAST) in the brains of offspring mice and the alteration in their experimental behavior scores. Furthermore, a therapeutic study was conducted on these neuropsychiatric disorder model mice using butyric acid, piceid, and metformin. It was found that some molecules could effectively improve the behavioral scores of neuropsychiatric model mice. Importantly, significant correlations between certain behavioral scores and p62 protein expression, as well as between the scores and GLAST expression, were recognized. This is the first report of a significant correlation between pathological behaviors and biochemical alterations in neuropsychiatric disorder model animals. This concept could contribute to the development of innovative treatments to at least ameliorate the symptoms of several psychiatric disorders.

Iowa Gambling Task performance in individuals with schizophrenia: the role of general versus specific cognitive abilities

Objective

We aimed to explore how specific cognitive processes, such as attention and executive functions, account for variance in decision-making measured by Iowa Gambling Task (IGT) performance among individuals with schizophrenia spectrum disorders.

Methods

Adults (N = 65, M age = 25.4) with schizophrenia spectrum disorders participating in a clinical trial (registered at clinicaltrials.gov NCT03048695) completed the IGT, neuropsychological tests of attention, response inhibition, mental flexibility, working memory, and planning, as well as subtests from the Wechsler tests of intelligence to estimate IQ. Associations between performance on specific tasks, a composite score of executive function and attention, and IGT performance measured in two ways, one using the total net score, decks (C+D) - (A+B) and the other as preference for decks with more frequent gains than losses, decks (B+D) - (A+C), were analyzed with correlational and hierarchical regression analysis controlling for estimated IQ and psychotic symptoms, measured by the Positive and Negative Syndrome Scale.

Results

In the regression analyses, the strongest predictor of IGT performance measured as the total net score was estimated IQ (b = 1.43, p <.001). Neither specific cognitive tasks nor the composite score of executive functioning significantly contributed to explaining variance in IGT total net score beyond IQ and symptoms of psychosis. However, IQ and symptoms of psychosis did not predict tendency towards selecting decks with different gain-to-loss frequency, whereas poorer composite executive functioning predicted a pattern of selecting decks A and C with more frequent losses, (b = 8.30, p <.05).

Discussion

The results suggest that both IQ and executive functions contribute to IGT performance, but in distinct ways. Whereas lower IQ may contribute to overall more disadvantageous decision-making, poorer executive functioning may contribute to a more risk-aversive decision-making style. A clinical implication may be that individuals with schizophrenia and lower IQ or poorer executive functioning will have a higher need for support and interventions targeting decision-making.

Parental mental disorders in patients with comorbid schizophrenia and obsessive-compulsive disorder: a nationwide family-link study

Schizophrenia is highly comorbid with obsessive-compulsive disorder (OCD); both conditions share numerous pathophysiological etiologies. We, thus, examined the risk of mental disorders in the parents of probands with schizophrenia, OCD, or both conditions. Between 2001 and 2011, we enrolled a nationwide cohort of 69,813 patients with schizophrenia, OCD, or both. The control cohort included 698,130 individuals matched for demographics. Poisson regression models were employed to examine the risk of six mental disorders in their parents, including schizophrenia, bipolar disorder, depressive disorder, OCD, alcohol use disorder, and substance use disorder. We stratified patients into schizophrenia-only, OCD-only, and dual-diagnosis groups, and the dual-diagnosis group was further divided into schizophrenia-first, OCD-first, and simultaneously diagnosed groups. Compared with controls, the schizophrenia, OCD, and dual-diagnosis groups had higher risks for the six mental disorders in their parents (range of odds ratio [OR] 1.50-7.83). The sub-analysis of the dual-diagnosis group showed that the schizophrenia-first, OCD-first, and simultaneously diagnosed groups had higher odds for schizophrenia, bipolar disorder, depressive disorder, and OCD (range of OR 1.64-6.45) in their parents than the control group; the simultaneously diagnosed and OCD-first diagnosed groups had a higher odds of parental substance use disorder, while the schizophrenia-first diagnosed group had a higher odds of parental alcohol use disorder. The interrelationship between OCD and schizophrenia is linked to bipolar disorder, depressive disorder, alcohol use disorder, and substance use disorder. The results have implications for mental health policy and future research.

Avatar Intervention in Virtual Reality for Cannabis Use Disorder in Individuals With Severe Mental Disorders: Results From a 1-Year, Single-Arm Clinical Trial

Background

The dual diagnosis of cannabis use disorder (CUD) and severe mental disorder (SMD) results in clinically complex individuals. Cannabis use is known to have negative consequences on psychiatric symptoms, medication compliance, and disease prognosis. Moreover, the effectiveness of currently available psychotherapeutic treatments is limited in this population. In this context, our research team developed avatar intervention, an approach using virtual reality as a therapeutic tool to treat CUD in individuals with SMD.

Objective

This pilot clinical trial aimed to evaluate, until the 1-year follow-up, the efficacy of avatar intervention for CUD among 32 participants with a dual diagnosis of SMD and CUD.

Methods

Over the course of the 8 intervention sessions, participants were given the opportunity to enter a dialogue in virtual reality with an avatar representing a person with a significant role in their consumption, who was animated in real time by a therapist. The primary outcomes were the quantity of cannabis consumed and the frequency of use. Secondary outcomes included severity of problematic cannabis use, motivation for change, protective strategies for cannabis use, consequences of cannabis use, psychiatric symptoms, and quality of life. Changes in reported outcomes during the assessment periods before the intervention; postintervention; and 3, 6, and 12 months after the end of the intervention were assessed using a linear mixed-effects model.

Results

Significant reductions were observed in the quantity of cannabis consumed, and these were maintained until the 12-month follow-up visit (d=0.804; P<.001; confirmed by urine quantification). Frequency of cannabis use showed a small significant reduction at the 3-month follow-up (d=0.384; P=.03). Moreover, improvements were observed in the severity of CUD, cannabis-related negative consequences, the motivation to change cannabis use, and the strategies used to mitigate harms related to cannabis use. Finally, moderate benefits were observed for quality of life and psychiatric symptoms.

Conclusions

Overall, this unique intervention shows promising results that seem to be maintained up to 12 months after the end of the intervention. With the aim of overcoming the methodological limitations of a pilot study, a single-blind randomized controlled trial is currently underway to compare the avatar intervention for CUD with a conventional addiction intervention.

Comorbid health outcomes in patients with schizophrenia: an umbrella review of systematic reviews and meta-analyses

There is no comprehensive umbrella review exploring the connection between schizophrenia and various health outcomes. Therefore, we aimed to systematically review existing meta-analyses about schizophrenia-associated comorbid health outcomes and validate the evidence levels. We performed an umbrella review of meta-analyses of observational studies to explore comorbid health outcomes in individuals with schizophrenia. Searches were conducted across PubMed/MEDLINE, EMBASE, ClinicalKey, and Google Scholar up to September 5, 2023, targeting meta-analyses of observational studies related to comorbid health outcomes in individuals with schizophrenia. We applied AMSTAR2 for data extraction and quality assessment, adhering to PRISMA guidelines. Evidence credibility was evaluated and categorized by evidence quality. Our protocol was registered with PROSPERO (CRD42024498833). Risk and protective factors were analyzed and presented through equivalent odds ratios (eRR). In this umbrella review, we analyzed 9 meta-analyses, including 88 original articles, covering 21 comorbid health outcomes with over 66 million participants across 19 countries. Patients with schizophrenia showed significant associations with multiple health outcomes, including asthma (eRR, 1.71 [95% CI, 1.05-2.78], class and quality of evidence [CE] = non-significant), chronic obstructive pulmonary disease (1.73 [1.25-2.37], CE = weak), pneumonia (2.63 [1.11-6.23], CE = weak), breast cancer of female patients (1.31 [1.04-1.65], CE = weak), cardiovascular disease (1.53 [1.12-2.11], CE = weak), stroke (1.71 [1.30-2.25], CE = weak), congestive heart failure (1.81 [1.21-2.69], CE = weak), sexual dysfunction (2.30 [1.75-3.04], CE = weak), fracture (1.63 [1.10-2.40], CE = weak), dementia (2.29 [1.19-4.39], CE = weak), and psoriasis (1.83 [1.18-2.83] CE = weak). Our study underscores the imperative for an integrated treatment approach to schizophrenia, highlighting its broad impact across respiratory, cardiovascular, sexual, neurological, and dermatological health domains. Given the predominantly non-significant to weak evidence levels, further studies are needed to reinforce our understanding.

RECAPACITA PROJECT: Impact of the New York Convention on capacity modification judgments in persons with severe mental disorders: A comparative study using mixed methodology

In 2013, Spain aligned its capacity modification processes (CM) legislation with the UN Convention on the rights of persons with disabilities, specifically for individuals with severe mental disorders (SMD). The reforms replaced incapacity verdicts with support provision and introduced the term "CM". However, the social impact of these changes remains uncertain. The RECAPACITA project was initiated to generate knowledge on SMD and CM, and this study aims to investigate modifications in CM sentences and associated terminology. Using a qualitative-quantitative methodology, content analysis was conducted on 56 sentences from individuals with SMD. Terminology analysis utilized 19 sentences to achieve information saturation. A comparison was made between sentences prior to 2013 and those spanning 2014 to 2023, analyzing the data through ANOVA and Bonferroni tests (significance level: 0.05). The analysis revealed that psychiatric illness, its evolution, lack of self-governance, and economic management were frequently mentioned aspects in the sentences. However, no significant correlations were found. Qualitatively, mentions of self-governance were more prevalent in sentences before 2013. Conversely, after 2013, there was an increased focus on substances use, lack of insight and medical adherence, and the need for support in daily life. The term "incapable person" appeared in 100% of the sentences, indicating no differences in terminology. The study suggests that current CM sentences provide increasingly individualized information, addressing the specific support needs of individuals. To enhance future legal proceedings, incorporating neuroscience in studying SMD individuals and reconsidering terminology based on Convention guidelines is recommended.

Cariprazine as a maintenance treatment in dual schizophrenia: a 6-month observational study in patients with schizophrenia and cannabis use disorder

Schizophrenia is often associated with substance use disorders, particularly cannabis use disorder (CUD). However, treatments frequently fail to address both conditions simultaneously. This study aimed to evaluate the antipsychotic effectiveness of cariprazine in patients with both schizophrenia and CUD in a real-world setting. A 6-month observational study was conducted on 58 patients diagnosed with schizophrenia and CUD, treated with cariprazine. Antipsychotic effectiveness was measured using the Positive and Negative Syndrome Scale and the Clinical Global Impression-Schizophrenia Scale, along with the Improvement and Severity scales. Cannabis consumption and addiction severity were assessed using the Cannabis Abuse Screening Test and the Severity of Dependence Scale, while functioning was evaluated with the Sheehan Disability Inventory. Cariprazine treatment resulted in significant improvements in schizophrenia symptoms (Positive and Negative Syndrome Scale change: -47.88 points, P < 0.0001; Clinical Global Impression-Schizophrenia Scale change: -8.26 points, P < 0.0001). Cannabis use and dependence also decreased (Cannabis Abuse Screening Test change: -7.0 points, P < 0.0001; Severity of Dependence Scale change: -7.88 points, P < 0.0001), alongside improvements in functioning (Sheehan Disability Inventory change: -9.48 points, P < 0.0001). These results suggest that cariprazine is effective for both schizophrenia and CUD, though further research is needed to confirm these findings.

Smoking behavior is associated with suicidality in individuals with psychosis and bipolar disorder: a systematic quantitative review and meta-analysis

Smoking behavior has been well-established to be more prevalent in individuals with psychosis and bipolar disorder compared to the general population. However, reports about higher suicide attempt prevalence of smoking compared to non-smoking patients suggest that smoking behavior may contribute to identifying at-risk groups of patients in a comparatively easy manner. In the present systematic quantitative review, we provide meta-analytical evidence on the smoking and suicide attempt link in 22 studies (k = 27 independent samples; N = 11,452) of patients with psychosis and bipolar disorder. We observed a small meaningful effect of smoking on suicide attempts (OR = 1.70; 95% CI [1.48; 1.95]), indicating that smokers have 1.70 the odds of having reported a suicide attempt compared to non-smokers. This effect generalized across diagnosis type (i.e., schizophrenia vs. bipolar spectrum disorder), sample type (i.e., in-vs. outpatients), and participant sex. However, the observed summary effect appeared somewhat inflated due to publication process-related mechanisms, showing some evidence for effect-inflating publication bias and a decline effect. In all, the presently observed smoking and suicide attempt link appears to be small but meaningful and robust, thus suggesting smoking status represents a useful variable for the identification of at-risk populations for suicide attempts.

The Resurgence of Exogenous Psychosis: A Phenomenological Examination of Substance-Induced Psychopathology

ABSTRACT

The psychopathological manifestations associated with substance use, including induced psychotic experiences, are increasingly relevant but not well-understood within the medical community. Novel psychoactive substances and potentiated old compounds like cannabis and cocaine have emerged as a global concern, especially among adolescents and young adults. Transition rates from substance-induced psychosis (SIP) to persistent psychosis are significant, particularly in cases of cannabis-induced psychosis. Scientific inquiry into induced psychotic phenomena has revealed differences between SIP and primary psychotic disorders, highlighting the risk factors associated with each. The concept of exogenous psychosis, including its toxic variant known as lysergic psychoma, provides valuable insights into the role of external factors in psychosis development. A phenomenological approach characterizes this disruption in perception as a shift in temporal and spatial dimensions, leading to auditory and visual hallucinations. The "twilight state" of consciousness plays a crucial role in the transition from substance use to psychosis, with implications for spatiality, intersubjectivity, and temporality. This complex path to psychosis challenges traditional diagnostic models and underscores the need for a more nuanced understanding of substance-induced psychopathological experiences.

Evaluating the Impact of Motivational Enhancement Therapy on Tobacco Cessation in Schizophrenia: A Comprehensive Review

Tobacco use is markedly prevalent among individuals with schizophrenia, presenting significant challenges to their physical health and psychiatric treatment. This comprehensive review evaluates the impact of motivational enhancement therapy (MET) on tobacco cessation in this population. Schizophrenia, a chronic mental disorder characterized by symptoms such as delusions and hallucinations, is frequently accompanied by high rates of smoking, which exacerbates health risks and complicates treatment regimens. MET, a client-centered approach rooted in motivational interviewing, aims to enhance intrinsic motivation for behavior change through empathetic and non-confrontational therapeutic sessions. This review synthesizes evidence from clinical studies on MET's effectiveness in promoting smoking cessation among individuals with schizophrenia. The review highlights the therapy's strengths, including its adaptability and client-focused nature, which are particularly beneficial for addressing the unique challenges faced by this population. It also discusses the broader health benefits of smoking cessation, such as improved physical health and enhanced efficacy of psychiatric medications. Despite promising results, the review identifies limitations and challenges in applying MET, such as potential barriers to implementation and the need for further research. In conclusion, MET offers a valuable intervention for tobacco cessation in individuals with schizophrenia, with the potential to significantly improve health outcomes and quality of life. Future research should focus on optimizing MET strategies and exploring their broader impacts on this vulnerable population.

An overview of the efficacy and safety of brexpiprazole for the treatment of schizophrenia in adolescents

INTRODUCTION

The onset of psychotic symptoms occurs prior to age 19 in 39% of the patients with schizophrenia. There are limited approved treatment options for adolescents with schizophrenia. Brexpiprazole was approved by the United States Food and Drug Administration (FDA) for treatment of schizophrenia in adolescents in 2022.

AREAS COVERED

Extrapolation of adult data to youth and use of pharmacologic modeling coupled with open long-term safety data were used by the FDA to approve brexpiprazole for adolescent schizophrenia. They were all reviewed herein.

EXPERT OPINION

D2 receptor partial agonist antipsychotic agents are preferred in the early phase of treatment of psychotic disorders. Approval of brexpiprazole in adolescent schizophrenia provides an additional option. Brexpiprazole was approved by the FDA on the basis of extrapolation of adult data without controlled trials in adolescents. This reduces placebo exposure in young people. Two previous agents (asenapine and ziprasidone) approved for adult schizophrenia failed to separate from placebo in adolescent schizophrenia studies; this partially undermines the process of extrapolation. For brexpiprazole, the paucity of data in adolescents relegates it to a second-line agent. More research on brexpiprazole is needed to delineate its relative role in the management of adolescent schizophrenia.

Environmental risk factors for schizophrenia and bipolar disorder from childhood to diagnosis: a Swedish nested case-control study

BACKGROUND

Shared genetic risk between schizophrenia (SCZ) and bipolar disorder (BD) is well-established, yet the extent to which they share environmental risk factors remains unclear. We compare the associations between environmental exposures during childhood/prior to disorder onset with the risk of developing SCZ and BD.

METHODS

We conducted a Swedish register-based nested case-control study using 4184 SCZ cases and 18 681 BD cases diagnosed 1988-2013. Cases were matched to five controls by birth year, birth region, and sex. Conditional logistic regression was used to estimate incidence rate ratios (IRR) for SCZ and BD for each exposure (severe childhood infections, adverse childhood experiences (ACEs), substance use disorders (SUDs), urban birth/longest residence).

RESULTS

All SUD types were associated with very high risk (IRR 4.9-25.5), and all forms of ACEs with higher risk (IRR 1.5-4.3) for both disorders. In the mutually adjusted models, ACEs demonstrated slightly higher risk for BD (SCZ IRR 1.30, 1.19-1.42; BD IRR 1.49, 1.44-1.55), while for SUD, risk was higher for SCZ (SCZ IRR 9.43, 8.15-10.92; BD IRR 5.50, 5.15-5.88). Infections were associated with increased risk of BD (IRR 1.21, 1.17-1.26) but not SCZ. Urban birth and urban longest residence were associated with higher risk of SCZ (IRR 1.19, 1.03-1.37), while only the combination of urban birth and rural longest residence showed higher risk for BD (IRR 1.24, 1.13-1.35).

CONCLUSIONS

There were both shared and unique environmental risk factors: SUDs and ACEs were risk factors for both disorders, while infections were more strongly associated with BD and urbanicity with SCZ.

Randomized Laboratory Study of Single-Dose Cannabis, Dronabinol, and Placebo in Patients With Schizophrenia and Cannabis Use Disorder

BACKGROUND AND HYPOTHESIS

Up to 43% of people with schizophrenia have a lifetime cannabis use disorder (CUD). Tetrahydrocannabinol (THC) has been shown to exacerbate psychosis in a dose-dependent manner, but little research has assessed its effects on schizophrenia and co-occurring CUD (SCZ-CUD). In this double-dummy, placebo-controlled trial (total n = 130), we hypothesized that a modest dose of THC would worsen cognitive function but not psychosis.

STUDY DESIGN

Effects of single-dose oral THC (15 mg dronabinol) or smoked 3.5% THC cigarettes vs placebo in SCZ-CUD or CUD-only on positive and negative symptoms of schizophrenia (only for SCZ-CUD), cognition, and drug experiences assessed several hours after drug administration. SCZ-only and healthy control participants were also assessed.

STUDY RESULTS

Drug liking was higher in THC groups vs placebo. Neither smoked THC nor oral dronabinol predicted positive or negative symptom subscale scores 2 and 5 h, respectively, after drug exposure in SCZ-CUD participants. The oral dronabinol SCZ-CUD group, but not smoked THC SCZ-CUD group, performed worse than placebo on verbal learning (B = -9.89; 95% CI: -16.06, -3.18; P = .004) and attention (B = -0.61; 95% CI: -1.00, -0.23; P = .002). Every 10-point increment in serum THC + THCC ng/ml was associated with increased negative symptoms (0.40 points; 95% CI: 0.15, 0.65; P = .001; subscale ranges 7-49) and trends were observed for worse positive symptoms and performance in verbal learning, delayed recall, and working memory.

CONCLUSIONS

In people with SCZ-CUD, a modest single dose of oral THC was associated with worse cognitive functioning without symptom exacerbation several hours after administration, and a THC dose-response effect was seen for negative symptoms.

Rethinking Mental Automatism: De Clérambault's Theory in the Age of Novel Psychoactive Drugs: Psychotropic Effects and Synthetic Psychosis

The widespread use of novel psychoactive substances (NPSs)-defined as new narcotic or psychotropic agents not classified under the Single Convention on Narcotic Drugs of 1961 or the Convention on Psychotropic Substances of 1971-poses a significant challenge to contemporary mental health paradigms due to their impact on psychiatric disorders. This study revisits and expands upon the theory of mental automatism as proposed by Gaëtan Gatian de Clérambault, aiming to elucidate the psychopathological mechanisms underlying substance-induced psychoses (SIP) and their distinction from non-induced psychoses (schizophrenia and related disorders). Through a phenomenological and clinical investigation, we explore the relevance of mental automatism in the development of toxic psychoses, drawing upon the historical and contemporary literature. This research highlights the psychopathological distinctions between induced and non-induced psychoses and the transition mechanisms from acute to chronic psychosis states. De Clérambault's theory, supplemented by Janet, Jackson, and Bonhoeffer's contributions, provides a foundational framework for understanding the genesis of SIP. Our findings suggest that NPS consumption, particularly among adolescents and psychiatric patients, significantly correlates with increased risks of SIP, marked by a transition to chronicity influenced by biological lesions triggered by substance use. Furthermore, we propose a comprehensive framework for SIP, integrating mental automatism, psychopathological distinctions, and transition mechanisms. This framework aims to refine diagnostic criteria and therapeutic approaches, addressing gaps in clinical practice and research. The study underscores the need for a nuanced understanding of SIP, advocating for a paradigm shift in psychiatric assessment and treatment approaches to better address the complexities of substance-induced mental health disorders.

Examining the impact of substance use on hospital length of stay in schizophrenia spectrum disorder: a retrospective analysis

BACKGROUND

Among patients diagnosed with schizophrenia, the presence of substance use poses an aggravating comorbidity, exerting a negative impact on the course of the disease, adherence to therapeutic regimens, treatment outcomes, duration of hospital stays, and the frequency of hospitalizations. The primary objective of the present study is to investigate the relationship between comorbid substance use disorders, antipsychotic treatment, and the length of stay in individuals hospitalized for treatment of schizophrenia.

METHODS

We conducted a retrospective analysis of electronic health records spanning a 12-month period, specifically focusing on adult patients diagnosed with schizophrenia who were discharged from the University Hospital of Psychiatry Zurich between January and December 2019. We documented the number and types of diagnosed substance use disorder, the antipsychotic treatment, the length of stay, and the number of previous hospitalizations for each patient.

RESULTS

Over a third (n = 328; 37.1%) of patients with schizophrenia had comorbid substance use with cannabis being the most frequent consumed substance. Patients with substance use (either single or multiple) were more frequently hospitalized; those with multiple substance use more frequently than those with a single substance use (F(2, 882) = 69.06; p < 0.001). There were no differences regarding the rate of compulsory admission. Patients with no substance use had a lower HoNOS score at discharge (F(2, 882) = 4.06). Patients with multiple substance use had a shorter length of stay (F(2, 882) = 9.22; p < 0.001), even after adjusting for duration of illness, previous hospitalizations, diagnosis, and antipsychotic treatment.

CONCLUSIONS

In patients with schizophrenia, comorbid single or multiple substance use has a relevant negative impact on treatment and thus on the course of disease. Substance use in patients with schizophrenia should therefore receive special attention in order to reduce re-hospitalization rates and improve the clinical outcome.

Impact of gaming disorder on first episode psychosis patients' evolution: Protocol for a multicentered prospective study

AIMS

The objective of this study is to underline the impact of Gaming Disorder on the clinical evolution of patients with First Episode Psychosis. The specific aims of the study are to determine the prevalence of gaming disorder among those patients and assess the consequences of gaming on their clinical trajectory.

METHODS

This is a prospective multicenter cohort study that will enrol 800 patients diagnosed with a first episode psychosis, with a follow-up period of up to 3 years. Using a systematic screening procedure for gaming disorder, the clinical staff will assess patients gaming habits at admission and every 6 months thereafter. Information from patients' medical records will also be extracted using the same timeframe.

RESULTS

The patients' characteristics at admission and during follow-up will be presented in the form of descriptive statistics and compared between different subgroups of patients using uni- and multivariate logistic regression models. Repeated measures ANCOVA will also be performed to analyse the impact of gaming disorders on patients' clinical path as assessed by the Positive and Negative Syndrome Scale and the Clinical Global Impression scale, considering covariates such as psychiatric diagnosis, pharmacological treatment, age, sex/gender, and duration of untreated psychosis.

CONCLUSION

These findings will guide the development of prevention, detection, and treatment strategies for the comorbidity between gaming disorder and first episode psychosis, ultimately improving the patients' recovery.

Modulation of mGlu5 reduces rewarding associative properties of nicotine via changes in mesolimbic plasticity: Relevance to comorbid cigarette smoking in psychosis

RATIONALE

Antipsychotic medications that are used to treat psychosis are often limited in their efficacy by high rates of severe side effects. Treatment success in schizophrenia is further complicated by high rates of comorbid nicotine use. Dopamine D2 heteroreceptor complexes have recently emerged as targets for the development of more efficacious pharmaceutical treatments for schizophrenia.

OBJECTIVE

The current study sought to explore the use of the positive allosteric modulator of the mGlu5 receptor 3-Cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl)benzamide (CDPPB) as a treatment to reduce symptoms related to psychosis and comorbid nicotine use.

METHODS

Neonatal treatment of animals with the dopamine D2-like receptor agonist quinpirole (NQ) from postnatal day (P)1-21 produces a lifelong increase in D2 receptor sensitivity, showing relevance to psychosis and comorbid tobacco use disorder. Following an 8-day conditioning paradigm, brain tissue in the mesolimbic pathway was analyzed for several plasticity markers, including brain derived neurotrophic factor (BDNF), phosphorylated p70 ribosomal S6 kinase (phospho-p70S6K), and cadherin-13 (Cdh13).

RESULTS

Pretreatment with CDPPB was effective to block enhanced nicotine conditioned place preference observed in NQ-treated animals. Pretreatment was additionally effective to block the nicotine-induced increase in BDNF and sex-dependent increases in cadherin-13 in the ventral tegmental area (VTA), as well as increased phospho-p70S6K in the nucleus accumbens (NAcc) shell found in NQ-treated animals.

CONCLUSION

In conjunction with prior work, the current study suggests positive allosteric modulation of the mGlu5 receptor, an emerging target for schizophrenia therapeutics, may be effective for the treatment of comorbid nicotine abuse in psychosis.

Sociodemographic and treatment-related determinants of recent substance use among adults with comorbid substance misuse and psychotic disorders discharged from substance use treatment

INTRODUCTION

Rates of alcohol and illicit substance use are higher among persons with psychotic disorders relative to the general population. The adverse health and psychological effects of substance use behaviors disproportionately impact persons with psychotic disorders. Prior research has shown that persons with psychotic disorders experience increased difficulty in reducing substance use behaviors, and interventions targeting substance use behavior change among this population have demonstrated limited effectiveness. One reason for this is that little is known about the factors that influence substance use and behavior change among this population. To address these disparities, the present study investigated sociodemographic and treatment-related factors of substance use recurrence among persons with psychotic disorders who received substance use treatment services.

METHODS

Data came from the 2015-2018 Treatment Episode Dataset-Discharges (TEDS-D). TEDS-D collects annual data on adolescent and adult discharges from state-certified substance use treatment centers in the United States. The study conducted all analyses with a subsample of 1956 adult discharges with a psychotic disorder who received services from an outpatient substance use treatment center for at least one month. χ2 tests of independence and multivariable logistic regression analyses were used to examine associations of sociodemographic and treatment-related characteristics with substance use recurrence while in treatment (α < 0.05 analyses). The study presents results from multivariable logistic regression models as adjusted odds ratios (AORs) with 95 % confidence intervals (CI).

RESULTS

Those who were age 50 or older, were referred to treatment by the criminal justice system, and attended substance use self-help groups had lower odds of substance use recurrence while in treatment. Sex, educational attainment, employment status, living situation, type of substance use, and treatment history were not significantly associated with substance use recurrence.

CONCLUSIONS

In designing treatment services, providers should consider whether focusing on sociodemographic, including cultural, factors can affect more positive substance use behavior change and other desired treatment outcomes among those with psychotic disorders and comorbid substance misuse. Further study is needed to identify these factors among specific subpopulations of those with psychotic disorders and substance misuse.

Therapeutic potential of gamma entrainment using sensory stimulation for cognitive symptoms associated with schizophrenia

Schizophrenia is a complex neuropsychiatric disorder with significant morbidity. Treatment options that address the spectrum of symptoms are limited, highlighting the need for innovative therapeutic approaches. Gamma Entrainment Using Sensory Stimulation (GENUS) is an emerging treatment for neuropsychiatric disorders that uses sensory stimulation to entrain impaired oscillatory network activity and restore brain function. Aberrant oscillatory activity often underlies the symptoms experienced by patients with schizophrenia. We propose that GENUS has therapeutic potential for schizophrenia. This paper reviews the current status of schizophrenia treatment and explores the use of sensory stimulation as an adjunctive treatment, specifically through gamma entrainment. Impaired gamma frequency entrainment is observed in patients, particularly in response to auditory and visual stimuli. Thus, sensory stimulation, such as music listening, may have therapeutic potential for individuals with schizophrenia. GENUS holds novel therapeutic potential to improve the lives of individuals with schizophrenia, but further research is required to determine the efficacy of GENUS, optimize its delivery and therapeutic window, and develop strategies for its implementation in specific patient populations.

Patient experiences with a primary care medical home tailored for people with serious mental illness

INTRODUCTION

People with serious mental illness (SMI) have low rates of primary care (PC) use and die years prematurely, mostly because of medical illnesses such as cardiovascular disease or cancer. To meet the needs of these individuals, a novel, specialized patient-centered medical home with care coordination ("SMI PACT") was developed and implemented in PC. This study qualitatively examined patients' experiences with this innovative care model.

METHOD

After implementation of the medical home in 2018, one-on-one semistructured interviews were conducted with 28 patients (32% women, 43% Black, and 25% Hispanic). Interviews were professionally transcribed and coded prior to thematic analysis.

RESULTS

Patients overwhelmingly described positive experiences with SMI PACT because of the qualities of interpersonal communication displayed by SMI PACT staff (e.g., nonjudgment, good listening, patience), structural features of the SMI PACT collaborative care model (e.g., frequent follow-up communication), and other unique aspects of the SMI PACT model tailored for SMI, such as easy-to-understand language. For these reasons, most patients expressed a desire to continue care in SMI PACT. Patients also self-reported improved engagement with their healthcare and self-management of diet, exercise, blood pressure, and diabetes control as a result of SMI PACT participation.

DISCUSSION

Patients enrolled in a specialized PC medical home identified clinician characteristics and behaviors that informed an overwhelmingly positive impression of the program model. Their experiences can guide dissemination of specialized PC models and integrated services for people with SMI. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Sexually transmitted infections, sexual life and risk behaviours of people living with schizophrenia: systematic review and meta-analysis

BACKGROUND

Sexually transmitted infections (STIs), along with sexual health and behaviour, have received little attention in schizophrenia patients.

AIMS

To systematically review and meta-analytically characterise the prevalence of STIs and sexual risk behaviours among schizophrenia patients.

METHOD

Web of Science, PubMed, BIOSIS, KCI-Korean Journal Database, MEDLINE, Russian Science Citation Index, SciELO and Cochrane Central Register were systematically searched from inception to 6 July 2023. Studies reporting on the prevalence or odds ratio of any STI or any outcome related to sexual risk behaviours among schizophrenia samples were included. PRISMA/MOOSE-compliant (CRD42023443602) random-effects meta-analyses were used for the selected outcomes. Q-statistics, I2 index, sensitivity analyses and meta-regressions were used. Study quality and publication bias were assessed.

RESULTS

Forty-eight studies (N = 2 459 456) reporting on STI prevalence (including 15 allowing for calculation of an odds ratio) and 33 studies (N = 4255) reporting on sexual risk behaviours were included. Schizophrenia samples showed a high prevalence of STIs and higher risks of HIV (odds ratio = 2.11; 95% CI 1.23-3.63), hepatitis C virus (HCV, odds ratio = 4.54; 95% CI 2.15-961) and hepatitis B virus (HBV; odds ratio = 2.42; 95% CI 1.95-3.01) infections than healthy controls. HIV prevalence was higher in Africa compared with other continents and in in-patient (rather than out-patient) settings. Finally, 37.7% (95% CI 31.5-44.4%) of patients were sexually active; 35.0% (95% CI 6.6-59.3%) reported consistent condom use, and 55.3% (95% CI 25.0-82.4%) maintained unprotected sexual relationships.

CONCLUSIONS

Schizophrenia patients have high prevalence of STIs, with several-fold increased risks of HIV, HBV and HCV infection compared with the general population. Sexual health must be considered as an integral component of care.

Prevalence, demographics and clinical characteristics of Internet addiction among Chinese adolescents with schizophrenia

Introduction

Several studies have reported that Internet addiction (IA) is more prevalent in the psychiatric disorder population. However, the prevalence of IA and its relationship with clinical variables among Chinese adolescents with schizophrenia is unclear. This study sought to investigate the prevalence of IA and its clinical correlates in Chinese adolescents with schizophrenia, which has not yet been reported.

Methods

Seven hundred and six inpatient adolescents with schizophrenia were recruited. All patients underwent Young's Internet Addiction Test (IAT) to measure Internet addiction, as well as the Positive and Negative Syndrome Scale (PANSS) for psychopathology.

Results

Our results showed that 186 patients had a total IAT score of 50 or more, bringing the prevalence of IA to 26.3%. Girls (21.7%, 92/424) were less likely to have combined IA than boys (33.3%, 94/282). Compared to those patients without IA, patients with IA had better socioeconomic status, higher probability of living in the city, higher levels of depressive symptoms, excited symptoms, and lower levels of concrete symptoms and PANSS total scores (all p<0.05). Further binary logistic regression analysis indicated that good socioeconomic status, living in the city and PANSS total scores were significantly associated with IA. In addition, correlation analysis showed significant correlations between IA total score and the following parameters: good socioeconomic status, living in the city, negative subscore, concrete subscore, depression subscore, excited subscore and PANSS total score (Bonferroni corrected all p <0.05).

Conclusion

The results of this study indicate that the prevalence of IA in Chinese adolescents with schizophrenia is higher than that in the general population. Several demographic and clinical variables are risk factors for IA in adolescents with schizophrenia.

Promising immunomodulators for management of substance and alcohol use disorders

INTRODUCTION

The neuroimmune system has emerged as a novel target for the treatment of substance use disorders (SUDs), with immunomodulation producing encouraging therapeutic benefits in both preclinical and clinical settings.

AREAS COVERED

In this review, we describe the mechanism of action and immune response to methamphetamine, opioids, cocaine, and alcohol. We then discuss off-label use of immunomodulators as adjunctive therapeutics in the treatment of neuropsychiatric disorders, demonstrating their potential efficacy in affective and behavioral disorders. We then discuss in detail the mechanism of action and recent findings regarding the use of ibudilast, minocycline, probenecid, dexmedetomidine, pioglitazone, and cannabidiol to treat (SUDs). These immunomodulators are currently being investigated in clinical trials described herein, specifically for their potential to decrease substance use, withdrawal severity, central and peripheral inflammation, comorbid neuropsychiatric disorder symptomology, as well as their ability to improve cognitive outcomes.

EXPERT OPINION

We argue that although mixed, findings from recent preclinical and clinical studies underscore the potential benefit of immunomodulation in the treatment of the behavioral, cognitive, and inflammatory processes that underlie compulsive substance use.

A systematic review and meta-analysis of synthetic cathinone use and psychosis

RATIONALE

Synthetic cathinones (SC), commonly referred to as "bath salts", are stimulants resembling the natural alkaloid cathinone found in the khat plant. These substances have the potential to induce serious health risks such as hallucinations, delusions, paranoia and agitation which can lead to substance-induced psychotic disorders. Despite growing concerns, there is a limited understanding of the association between SC consumption and the devolvement of such psychopathologies.

METHODS

We conducted a systematic review to investigate the frequency of substance-induced psychotic disorder (SIPD) and associated conditions in humans following synthetic cathinone consumption. We qualitatively and quantitatively analyzed SC exposure cases.

RESULTS

A total of 32 studies were included, with a diverse range of demographics, synthetic cathinone types, and consumption patterns. The proportion of individuals developing psychotic symptoms was reported at 0.380 (Random-effects model, 95% CI 0.289 - 0.475). Additionally, the significant heterogeneity in diagnostic approaches limited our ability to provide a precise estimate of prevalence.

CONCLUSIONS

Synthetic cathinone consumption is associated with the risk of developing psychotic symptoms as indicated by the prevalence of hallucinations and/or delusions. Due to the lack of information on classifying factors, particularly duration of symptoms, we are unable to conclude synthetic cathinone-induced psychosis. Further research is warranted to elucidate the underlying mechanism linking synthetic cathinone consumption and psychosis. This review underscores the urgency of addressing the growing health risks posed by synthetic cathinone use. Additionally, it highlights the necessity of proper quantification of psychotic symptoms through scales and reporting of classification criteria to accurately diagnose SIPD.

Differential effects of cannabis constituents on schizophrenia-related psychosis: a rationale for incorporating cannabidiol into a schizophrenia therapeutic regimen

Schizophrenia is a serious mental health disorder that confers one of the highest mortality rates of all psychiatric illnesses. Although the disorder's psychotic symptoms are treatable with conventional antipsychotics, they remain incurable. Moreover, medication adherence is poor, and individuals with schizophrenia choose to self-medicate with illicit substances, including cannabis. It is well-established that the delta-9-tetrahydrocannabinol (delta-9-THC) component of cannabis elicits psychotomimetic effects at high doses; worsens schizophrenia-related psychosis; commonly develops into cannabis use disorder in individuals with schizophrenia; and increases the risk of earlier-onset schizophrenia symptoms in those harboring genetic susceptibility. However, individuals with schizophrenia commonly use cannabis and cannabis derivatives such as cannabidiol (CBD). These products seem to alleviate psychotic symptoms and relieve adverse side effects of antipsychotic medications. Therefore, one notion that has gained traction is the potential utility of cannabis-derived cannabidiol (CBD) as adjunct treatment to reduce schizophrenia-associated psychosis and other symptoms. Currently, preclinical and clinical data remain inconclusive. The present review distinguishes the mechanisms underlying schizophrenia-associated vs. cannabis-induced psychosis; reviews the evidence for delta-9-THC-mediated exacerbation vs. CBD-mediated amelioration of schizophrenia-associated psychosis; and describes potential approaches for incorporating CBD into schizophrenia therapeutic regimen in a safe and efficacious manner.

Black family members' cultural beliefs and experiences regarding substance use and misuse by relatives: A focused ethnography

Research explored substance use in Black communities in Canada, but a gap exists about the experiences of Black family members, caring for relatives with substance misuse within the Canadian context. Black family members are defined as African Canadians, Caribbean Canadian or Caribbean Blacks. This paper explores Black family members' beliefs and experiences regarding their relatives' psychoactive substance use and misuse. A focused ethnography was conducted with 26 Black family members with 17 participants originated from various parts of Africa, and nine participants originated from parts of the Caribbean. Participants comprised of mothers (n = 5), fathers (n = 2), step-fathers (n = 1), husbands (n = 1), wives (n = 2), uncles (n = 5), aunties (n = 2), siblings (n = 5), in-laws (n = 2), and guardians (n = 1). Three themes were generated: cultural beliefs and perceptions regarding substance use and misuse of family relatives; "When he starts drinking, hell breaks loose": Perceived impact of substance misuse on family safety and stability; and, the experiences of stigma and the keeping of secrets. Prioritizing public health approaches, such as public policies and campaigns that dismantle stigma and systemic barriers, and increase awareness about substance use and harm reduction interventions among Black communities.

Carepath for overcoming psychosis early (COPE): first 5 years of clinical operation and prospective research in the Cavan-Monaghan early intervention service

OBJECTIVES

As Ireland confronts the many challenges of broadening the introduction of early intervention services (EIS) for first episode psychosis (FEP) as national policy, this article describes Carepath for Overcoming Psychosis Early (COPE), the EIS of Cavan-Monaghan Mental Health Service, and presents prospective research findings during its first 5 years of operation.

METHODS

COPE was launched as a rural EIS with an embedded research protocol in early 2012, following an education programme for general practitioners (GPs). Here, operational activities are documented and research findings presented through to late 2016.

RESULTS

During this period, 115 instances of FEP were incepted into COPE, 70.4% via their GP and 29.6% via the Emergency Department. The annual rate of inception was 24.8/100,000 of population aged > 15 years and was 2.1-fold more common among men than women. Mean duration of untreated psychosis was 5.7 months and median time from first psychotic presentation to initiation of antipsychotic treatment was zero days. Assessments of psychopathology, neuropsychology, neurology, premorbid functioning, quality of life, insight, and functionality compared across 10 DSM-IV psychotic diagnoses made at six months following presentation indicated minimal differences between them, other than more prominent negative symptoms in schizophrenia and more prominent mania in bipolar disorder.

CONCLUSIONS

COPE illustrates the actuality of introducing and the challenges of operating a rural EIS for FEP. Prospective follow-up studies of the 5-year COPE cohort should inform on the effectiveness of this EIS model in relation to long-term outcome in psychotic illness across what appear to be arbitrary diagnostic boundaries at FEP.

Association between psychosis and substance use in Kenya. Findings from the NeuroGAP-Psychosis study

Background

Substance use is prevalent among people with mental health issues, and patients with psychosis are more likely to use and misuse substances than the general population. Despite extensive research on substance abuse among the general public in Kenya, there is a scarcity of data comparing substance use among people with and without psychosis. This study investigates the association between psychosis and various substances in Kenya.

Methods

This study utilized data from the Neuro-GAP Psychosis Case-Control Study between April 2018 and December 2022. The KEMRI-Wellcome Trust Research Programme recruited participants from various sites in Kenya, including Kilifi County, Malindi Sub-County, Port Reitz and Coast General Provincial Hospitals, and Moi Teaching and Referral Hospital, as well as affiliated sites in Webuye, Kapenguria, Kitale, Kapsabet, and Iten Kakamega. The collected data included sociodemographic information, substance use, and clinical diagnosis. We used the summary measures of frequency (percentages) and median (interquartile range) to describe the categorical and continuous data, respectively. We examined the association between categorical variables related to psychosis using the chi-square test. Logistic regression models were used to assess the factors associated with the odds of substance use, considering all relevant sociodemographic variables.

Results

We assessed a total of 4,415 cases and 3,940 controls. Except for alcohol consumption (p-value=0.41), all forms of substance use showed statistically significant differences between the case and control groups. Cases had 16% higher odds of using any substance than controls (aOR: 1.16, 95%CI: 1.05-1.28, p=0.005). Moreover, males were 3.95 times more likely to use any substance than females (aOR:3.95; 95%CI: 3.43-4.56). All the categories of living arrangements were protective against substance use.

Conclusion

The findings of this study suggest that psychotic illnesses are associated with an increased likelihood of using various substances. These findings are consistent with those of previous studies; however, it is crucial to investigate further the potential for reverse causality between psychosis and substance abuse using genetically informed methods.

A whole-brain neuromark resting-state fMRI analysis of first-episode and early psychosis: Evidence of aberrant cortical-subcortical-cerebellar functional circuitry

Psychosis (including symptoms of delusions, hallucinations, and disorganized conduct/speech) is a main feature of schizophrenia and is frequently present in other major psychiatric illnesses. Studies in individuals with first-episode (FEP) and early psychosis (EP) have the potential to interpret aberrant connectivity associated with psychosis during a period with minimal influence from medication and other confounds. The current study uses a data-driven whole-brain approach to examine patterns of aberrant functional network connectivity (FNC) in a multi-site dataset comprising resting-state functional magnetic resonance images (rs-fMRI) from 117 individuals with FEP or EP and 130 individuals without a psychiatric disorder, as controls. Accounting for age, sex, race, head motion, and multiple imaging sites, differences in FNC were identified between psychosis and control participants in cortical (namely the inferior frontal gyrus, superior medial frontal gyrus, postcentral gyrus, supplementary motor area, posterior cingulate cortex, and superior and middle temporal gyri), subcortical (the caudate, thalamus, subthalamus, and hippocampus), and cerebellar regions. The prominent pattern of reduced cerebellar connectivity in psychosis is especially noteworthy, as most studies focus on cortical and subcortical regions, neglecting the cerebellum. The dysconnectivity reported here may indicate disruptions in cortical-subcortical-cerebellar circuitry involved in rudimentary cognitive functions which may serve as reliable correlates of psychosis.

The schizophrenia syndrome, circa 2024: What we know and how that informs its nature

With new data about different aspects of schizophrenia being continually generated, it becomes necessary to periodically revisit exactly what we know. Along with a need to review what we currently know about schizophrenia, there is an equal imperative to evaluate the construct itself. With these objectives, we undertook an iterative, multi-phase process involving fifty international experts in the field, with each step building on learnings from the prior one. This review assembles currently established findings about schizophrenia (construct, etiology, pathophysiology, clinical expression, treatment) and posits what they reveal about its nature. Schizophrenia is a heritable, complex, multi-dimensional syndrome with varying degrees of psychotic, negative, cognitive, mood, and motor manifestations. The illness exhibits a remitting and relapsing course, with varying degrees of recovery among affected individuals with most experiencing significant social and functional impairment. Genetic risk factors likely include thousands of common genetic variants that each have a small impact on an individual's risk and a plethora of rare gene variants that have a larger individual impact on risk. Their biological effects are concentrated in the brain and many of the same variants also increase the risk of other psychiatric disorders such as bipolar disorder, autism, and other neurodevelopmental conditions. Environmental risk factors include but are not limited to urban residence in childhood, migration, older paternal age at birth, cannabis use, childhood trauma, antenatal maternal infection, and perinatal hypoxia. Structural, functional, and neurochemical brain alterations implicate multiple regions and functional circuits. Dopamine D-2 receptor antagonists and partial agonists improve psychotic symptoms and reduce risk of relapse. Certain psychological and psychosocial interventions are beneficial. Early intervention can reduce treatment delay and improve outcomes. Schizophrenia is increasingly considered to be a heterogeneous syndrome and not a singular disease entity. There is no necessary or sufficient etiology, pathology, set of clinical features, or treatment that fully circumscribes this syndrome. A single, common pathophysiological pathway appears unlikely. The boundaries of schizophrenia remain fuzzy, suggesting the absence of a categorical fit and need to reconceptualize it as a broader, multi-dimensional and/or spectrum construct.

Schizophrenia and Emergency Medicine

Schizophrenia is a chronic condition characterized by positive symptoms (auditory hallucinations, delusion), negative symptoms (avolition, social withdrawal), and disorganized thoughts/behaviors. Although the pathophysiology is incompletely understood, several neurobiological mechanisms have been proposed. Treatment usually involves antipsychotic medication as well as psychotherapy and supportive services. When evaluating patients in the emergency department, acute safety considerations are paramount. Patients should be assessed for suicide risk, violence risk, inability to care for self, and the risk of being the victim of a crime. Persons with schizophrenia are at an increased risk of substance use and a variety of medical problems.

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.

Life engagement in people living with schizophrenia: predictors and correlates of patient life engagement in a large sample of people living in the community

BACKGROUND

Life engagement represents a holistic concept that encompasses outcomes reflecting life-fulfilment, well-being and participation in valued and meaningful activities, which is recently gaining attention and scientific interest. Despite its conceptual importance and its relevance, life engagement represents a largely unexplored domain in schizophrenia. The aims of the present study were to independently assess correlates and predictors of patient life engagement in a large and well-characterized sample of schizophrenia patients.

METHODS

To assess the impact of different demographic, clinical, cognitive and functional parameters on life engagement in a large sample of patients with schizophrenia, data from the social cognition psychometric evaluation project were analyzed.

RESULTS

Overall schizophrenia and depressive symptom severity, premorbid IQ, neurocognitive performance, social cognition performance both in the emotion processing and theory of mind domains, functional capacity, social skills performance and real-world functioning in different areas all emerged as correlates of patient life engagement. Greater symptom severity and greater impairment in real-world interpersonal relationships, social skills, functional capacity and work outcomes emerged as individual predictors of greater limitations in life engagement.

CONCLUSIONS

Life engagement in people living with schizophrenia represents a holistic and complex construct, with several different clinical, cognitive and functional correlates. These features represent potential treatment targets to improve the clinical condition and also facilitate the process of recovery and the overall well-being of people living with schizophrenia.

Cannabis and Psychosis

Psychosis and cannabis use may overlap in multiple ways in young people. Research suggests that cannabis use increases risk for having psychotic symptoms, both attenuated (subthreshold) and acute. Cannabis use may also exacerbate psychosis symptoms among young people with underlying psychosis risk and psychotic disorders. Although there are suggestions for treating co-occurring psychosis and cannabis use in young people (e.g., incorporating cannabis use assessment and treatment strategies into specialized early psychosis care), there are many gaps in clinical trial research to support evidence-based treatment of these overlapping concerns.

The Medication Use Issues and Challenges of Mental Illness Exacerbation in Patients with Schizophrenia: A Qualitative Study in Thailand

Purpose

Patients with schizophrenia often experience mental illness exacerbations, which lead to frequent re-hospitalization. Non-adherence to medication is the main cause of relapses, despite many patients requiring lifelong treatment. Non-adherence consequences include higher re-admission and suicide rates, worse progression of mental illness, higher rates of violence by patients with mental illness, and increased use of emergency psychiatric services. This directly impacts the cost and workload of the mental healthcare system. This study aims to understand medication non-adherence among schizophrenia patients in Thailand based on the country's specific context.

Patients and Methods

This qualitative research study explored the causes of non-adherence to medication and health perceptions among patients with schizophrenia in Thailand. Five patients with schizophrenia were included in this study. Data was collected through in-depth interviews, recordings of treatments, and field notes based on the interpretive perspective of key informants with the concept of phenomenology.

Results

Thematic analysis revealed two main themes associated with mental illness exacerbation: triggers of exacerbation and medication non-adherence. The triggers that emerged from the data were substance abuse and psychological stress. Medication non-adherence issues were misunderstandings about mental illness and its treatment, lack of participation in treatment, and difficulty accessing mental health services.

Conclusion

This study explored the importance of medication adherence in patients with schizophrenia. Non-adherence to medication can worsen mental illness and create a vicious cycle that makes treatment more challenging. Substance abuse and psychological stress can also exacerbate this cycle. Mental health services should strive to improve medication adherence strategies and offer social support to prevent harmful behaviors and break the vicious cycle.

Transition to Schizophrenia Spectrum Disorder Following Emergency Department Visits Due to Substance Use With and Without Psychosis

Importance

Episodes of substance-induced psychosis are associated with increased risk of developing a schizophrenia spectrum disorder. However, there are limited data on the transition risk for substance use without psychosis.

Objectives

To quantify the risk of transition to schizophrenia spectrum disorder following an incident emergency department (ED) visit for (1) substance-induced psychosis and (2) substance use without psychosis and to explore factors associated with transition.

Design, Settings, and Participants

A population-based retrospective cohort study (January 2008 to March 2022) of all individuals, aged 14 to 65 years, in Ontario, Canada, with no history of a psychotic disorder. Individuals with incident ED visits for substance use with and without psychosis were compared with members of the general population.

Main Outcomes and Measures

Transition to schizophrenia spectrum disorder using a chart-validated algorithm. Associations between ED visits for substance use and subsequent transition were estimated using cause-specific hazard models.

Results

The study included 9 844 497 individuals, aged 14 to 65 years (mean [SD] age, 40.2 [14.7] years; 50.2% female) without a history of psychosis. There were 407 737 individuals with an incident ED visit for substance use, of which 13 784 (3.4%) ED visits were for substance-induced psychosis. Individuals with substance-induced psychosis were at a 163-fold (age- and sex-adjusted hazard ratio [aHR], 163.2; 95% CI, 156.1-170.5) increased risk of transitioning, relative to the general population (3-year risk, 18.5% vs 0.1%). Individuals with an ED visit for substance use without psychosis had a lower relative risk of transitioning (aHR, 9.8; 95% CI, 9.5-10.2; 3-year risk, 1.4%), but incurred more than 3 times the absolute number of transitions (9969 vs 3029). Cannabis use had the highest transition risk among visits with psychosis (aHR, 241.6; 95% CI, 225.5-258.9) and the third-highest risk among visits without psychosis (aHR, 14.3; 95% CI, 13.5-15.2). Younger age and male sex were associated with a higher risk of transition, and the risk of male sex was greater in younger compared with older individuals, particularly for cannabis use.

Conclusions and Relevance

The findings of this cohort study suggest that ED visits for substance use were associated with an increased risk of developing a schizophrenia spectrum disorder. Although substance-induced psychoses had a greater relative transition risk, substance use without psychosis was far more prevalent and resulted in a greater absolute number of transitions. Several factors were associated with higher transition risk, with implications for counseling and early intervention.

Prenatal risk factors and postnatal cannabis exposure: Assessing dual models of schizophrenia-like rodents

Schizophrenia (SCZ) is a multifactorial neurodevelopmental disorder caused by genetic and environmental alterations, especially during prenatal stages. On the other hand, cannabis consumption in adolescence has been also linked to an increased risk of developing SCZ. The combination of both hits has been proposed as the dual hit hypothesis of SCZ. We systematically reviewed prenatal environmental alterations and cannabis consumption during adolescence that are associated with an increased risk of SCZ, following the PRISMA model. The analysis focused on dual animal models where the first hit is prenatal environmental exposure and the second hit consists of postnatal cannabis exposure. The articles were evaluated by three independent reviewers based on inclusion criteria. We extracted the first author´s name, year, model species, sex and analysis. The articles reported on dual murine models and their effects on weight, behavior, genetics, electrophysiology and brain structure and function. We conclude that the defects caused by the dual hits depend on the sex of the model, as well as type of hits.

Revealing the impact of psychiatric comorbidities on treatment outcome in early psychosis using counterfactual model explanation

Introduction

Psychiatric comorbidities have a significant impact on the course of illness in patients with schizophrenia spectrum disorders. To accurately predict outcomes for individual patients using computerized prognostic models, it is essential to consider these comorbidities and their influence.

Methods

In our study, we utilized a multi-modal deep learning architecture to forecast symptomatic remission, focusing on a multicenter sample of patients with first-episode psychosis from the OPTiMiSE study. Additionally, we introduced a counterfactual model explanation technique to examine how scores on the Mini International Neuropsychiatric Interview (MINI) affected the likelihood of remission, both at the group level and for individual patients.

Results

Our findings at the group level revealed that most comorbidities had a negative association with remission. Among them, current and recurrent depressive disorders consistently exerted the greatest negative impact on the probability of remission across patients. However, we made an interesting observation: current suicidality within the past month and substance abuse within the past 12 months were associated with an increased chance of remission in patients. We found a high degree of variability among patients at the individual level. Through hierarchical clustering analysis, we identified two subgroups: one in which comorbidities had a relatively limited effect on remission (approximately 45% of patients), and another in which comorbidities more strongly influenced remission. By incorporating comorbidities into individualized prognostic prediction models, we determined which specific comorbidities had the greatest impact on remission at both the group level and for individual patients.

Discussion

These results highlight the importance of identifying and including relevant comorbidities in prediction models, providing valuable insights for improving the treatment and prognosis of patients with psychotic disorders. Furthermore, they open avenues for further research into the efficacy of treating these comorbidities to enhance overall patient outcomes.

Beyond the Binary: Gender Inclusivity in Schizophrenia Research

Schizophrenia is a severe neuropsychiatric disorder with significant differences in the incidence and symptomology between cisgender men and women. In recent years, considerably more attention has been on the inclusion of sex and gender in schizophrenia research. However, the majority of this research has failed to consider gender outside of the socially constructed binary of men and women. As a result, little is known about schizophrenia in transgender and gender-nonconforming populations. In this review, we present evidence showing that transgender and gender-nonconforming individuals have elevated risk of developing schizophrenia, and we discuss minority stress theory and other potential factors that may contribute to this risk. The need for inclusion of transgender and gender-nonconforming communities in schizophrenia research is emphasized, alongside a discussion on considerations and challenges associated with this type of research. Finally, we offer specific strategies to make research on schizophrenia, and research on other neuropsychiatric disorders, more inclusive of those populations that do not fall within the socially constructed gender binary. If we are to succeed in the development of more personalized therapeutic approaches for all, a better understanding of the variability of the human brain is needed.

The association between exposure to clozapine, olanzapine, and quetiapine and the outcomes perimyocarditis and heart failure: A population-based cohort study

The risk of cardiac adverse events following clozapine use is debated and is unknown for the chemically related and widely used antipsychotics olanzapine and quetiapine. National Swedish registers were used to identify all patients 16-75 years old with antipsychotic dispensations between 2005 and 2018. The short-term outcome was a diagnosis of perimyocarditis (pericarditis and/or myocarditis) within two months of first dispensation, and the long-term outcome was heart failure (including cardiomyopathy) within three years. Cox regressions with time varying exposure were used to estimate hazard rates (HR) and their 95% confidence intervals (CI). A total of 201,045 individuals were included in the cohort. The risk of developing perimyocarditis during clozapine treatment tripled compared to no antipsychotic treatment (HR 3.4, CI 1.6-7.3), although the absolute rate remained comparably low. The long-term risk of heart failure during clozapine treatment was also elevated (HR 1.3, CI 1.1-1.7). Treatment with either or both olanzapine or quetiapine was not associated with an increased relative risk of perimyocarditis, or heart failure compared to no antipsychotic treatment. Clozapine use is therefore associated with a substantially elevated short-term risk of perimyocarditis and an increased risk of heart failure within three years.

Impaired extinction of operant cocaine in a genetic mouse model of schizophrenia risk

BACKGROUND

Individuals with schizophrenia have high rates of comorbid substance use problems. One potential explanation for this comorbidity is similar neuropathophysiology in substance use and schizophrenia, which may arise from shared genetic risk factors between the two disorders. Here we investigated if genetic risk for schizophrenia could affect drug reward and reinforcement for cocaine in an established mouse model of genetic risk for schizophrenia, the neuregulin 1 transmembrane domain heterozygous (Nrg1 TM HET) mouse.

METHODS

We examined drug-induced locomotor sensitization and conditioned place preference for several cocaine doses (5, 10, 20, 30 mg/kg) in male adult Nrg1 TM HET and wild-type-like (WT) littermates. We also investigated intravenous self-administration of and motivation for cocaine (doses 0.1, 0.5, 1 mg/kg/infusion), as well as extinction and cue-induced reinstatement of cocaine. In a follow-up experiment, we examined self-administration, extinction and cue-induced reinstatement of a natural reward, oral sucrose.

RESULTS

Cocaine preference was similar between Nrg1 TM HET mice and WT littermates at all doses tested. Locomotor sensitization to cocaine was not affected by Nrg1 genotype at any dose. Although self-administration and motivation for cocaine was unaffected, extinction of cocaine self-administration was impaired in Nrg1 TM HET compared to WT controls, and cue-induced reinstatement was greater in Nrg1 mutants in the middle of the reinstatement session. Sucrose self-administration and extinction thereof was not affected by genotype, but inactive lever responding was elevated during cue-induced reinstatement for operant sucrose in Nrg1 TM HET mice compared to WTs.

DISCUSSION

These results suggest impaired response inhibition for cocaine in Nrg1 TM HET mice and suggests Nrg1 mutation may contribute to behaviours which can limit control over cocaine use.

Neurobehavioral risk factors influence prevalence and severity of hazardous substance use in youth at genetic and clinical high risk for psychosis

Background

Elevated rates of alcohol, tobacco, and cannabis use are observed in both patients with psychotic disorders and individuals at clinical high risk for psychosis (CHR-P), and strong genetic associations exist between substance use disorders and schizophrenia. While individuals with 22q11.2 deletion syndrome (22qDel) are at increased genetic risk for psychosis, initial evidence suggests that they have strikingly low rates of substance use. In the current study, we aimed to directly compare substance use patterns and their neurobehavioral correlates in genetic and clinical high-risk cohorts.

Methods

Data on substance use frequency and severity, clinical symptoms, and neurobehavioral measures were collected at baseline and at 12-month follow-up visits in two prospective longitudinal cohorts: participants included 89 22qDel carriers and 65 age and sex-matched typically developing (TD) controls (40.67% male, Mage = 19.26 ± 7.84 years) and 1,288 CHR-P youth and 371 matched TD controls from the North American Prodrome Longitudinal Study-2 and 3 (55.74% male; Mage = 18.71 ± 4.27 years). Data were analyzed both cross-sectionally and longitudinally using linear mixed effects models.

Results

Controlling for age, sex, and site, CHR-P individuals had significantly elevated rates of tobacco, alcohol, and cannabis use relative to TD controls, whereas 22qDel had significantly lower rates. Increased substance use in CHR-P individuals was associated with increased psychosis symptom severity, dysphoric mood, social functioning, and IQ, while higher social anhedonia was associated with lower substance use across all domains at baseline. These patterns persisted when we investigated these relationships longitudinally over one-year. CHR-P youth exhibited significantly increased positive psychosis symptoms, dysphoric mood, social functioning, social anhedonia, and IQ compared to 22qDel carriers, and lower rates of autism spectrum disorder (ASD) compared to 22qDel carriers, both at baseline and at 1 year follow-up.

Conclusion

Individuals at genetic and CHR-P have strikingly different patterns of substance use. Factors such as increased neurodevelopmental symptoms (lower IQ, higher rates of ASD) and poorer social functioning in 22qDel may help explain this distinction from substance use patterns observed in CHR-P individuals.