Comorbid substance-use in schizophrenia: relation to positive and negative symptoms

Gender differences in first episode psychosis: Some arguments to develop gender specific treatment strategies

INTRODUCTION

Some aspects of gender differences in patients with schizophrenia spectrum disorders (SSD) have been studied, especially in cross-sectional designs and with a short-term follow-up. However, only a few studies have considered the evolution during the follow-up of SSD patients according to their gender. In this study, we explore gender differences from the time of entry in an early intervention program for psychosis, up to three years follow-up.

METHODS

We conducted a prospective study including a cohort of 474 patients treated at the Treatment and Early Intervention in Psychosis (TIPP) program, 319 men and 155 women, having presented a first episode of psychosis (FEP). Data regarding premorbid and baseline sociodemographic, psychopathological and patient functioning, were collected. These data were reassessed longitudinally after 2, 6, 12, 18, 24, 30 and 36 months after entry in TIPP.

RESULTS

Regarding premorbid and baseline characteristics, woman developed threshold symptoms of a FEP 1 year later than men on average. Women were more likely to be married, men were more likely to live in pension or care home facility or to be homeless. Women displayed a higher rate of history of suicide attempts and exposure to childhood trauma, while men were more likely to have a forensic history, a history of abuse of alcohol and cannabis as well as a dependency to cannabis at the time of entry in TIPP. Regarding evolution, men were more prone to violent acts and were less likely to decrease their usage of substances. The longitudinal analysis highlighted that men displayed greater negative symptoms over the entire treatment period, lower functioning after 6 months and on all assessment points after. Both genders displayed similar rate of improvement in these 3 dimensions over time.

CONCLUSION

Our study confirms that there are some gender differences in the early phase of psychosis that may require differentiation of assessment and treatment to improve recovery.

Research landscape analysis on dual diagnosis of substance use and mental health disorders: key contributors, research hotspots, and emerging research topics

BACKGROUND

Substance use disorders (SUDs) and mental health disorders (MHDs) are significant public health challenges with far-reaching consequences on individuals and society. Dual diagnosis, the coexistence of SUDs and MHDs, poses unique complexities and impacts treatment outcomes. A research landscape analysis was conducted to explore the growth, active countries, and active journals in this field, identify research hotspots, and emerging research topics.

METHOD

A systematic research landscape analysis was conducted using Scopus to retrieve articles on dual diagnosis of SUDs and MHDs. Inclusion and exclusion criteria were applied to focus on research articles published in English up to December 2022. Data were processed and mapped using VOSviewer to visualize research trends.

RESULTS

A total of 935 research articles were found. The number of research articles on has been increasing steadily since the mid-1990s, with a peak of publications between 2003 and 2012, followed by a fluctuating steady state from 2013 to 2022. The United States contributed the most articles (62.5%), followed by Canada (9.4%). The Journal of Dual Diagnosis, Journal of Substance Abuse Treatment, and Mental Health and Substance Use Dual Diagnosis were the top active journals in the field. Key research hotspots include the comorbidity of SUDs and MHDs, treatment interventions, quality of life and functioning, epidemiology, and the implications of comorbidity. Emerging research topics include neurobiological and psychosocial aspects, environmental and sociocultural factors, innovative interventions, special populations, and public health implications.

CONCLUSIONS

The research landscape analysis provides valuable insights into dual diagnosis research trends, active countries, journals, and emerging topics. Integrated approaches, evidence-based interventions, and targeted policies are crucial for addressing the complex interplay between substance use and mental health disorders and improving patient outcomes.

Association between cannabis use and symptom dimensions in schizophrenia spectrum disorders: an individual participant data meta-analysis on 3053 individuals

Background

The association between cannabis use and positive symptoms in schizophrenia spectrum disorders is well documented, especially via meta-analyses. Yet, findings are inconsistent regarding negative symptoms, while other dimensions such as disorganization, depression, and excitement, have not been investigated. In addition, meta-analyses use aggregated data discarding important confounding variables which is a source of bias.

Methods

PubMed, ScienceDirect and PsycINFO were used to search for publications from inception to September 27, 2022. We contacted the authors of relevant studies to extract raw datasets and perform an Individual Participant Data meta-analysis (IPDMA). Inclusion criteria were: psychopathology of individuals with schizophrenia spectrum disorders assessed by the Positive and Negative Syndrome Scale (PANSS); cannabis-users had to either have a diagnosis of cannabis use disorder or use cannabis at least twice a week. The main outcomes were the PANSS subscores extracted via the 3-factor (positive, negative and general) and 5-factor (positive, negative, disorganization, depression, excitement) structures. Preregistration is accessible via Prospero: ID CRD42022329172.

Findings

Among the 1149 identified studies, 65 were eligible and 21 datasets were shared, totaling 3677 IPD and 3053 complete cases. The adjusted multivariate analysis revealed that relative to non-use, cannabis use was associated with higher severity of positive dimension (3-factor: Adjusted Mean Difference, aMD = 0.34, 95% Confidence Interval, CI = [0.03; 0.66]; 5-factor: aMD = 0.38, 95% CI = [0.08; 0.63]), lower severity of negative dimension (3-factor: aMD = -0.49, 95% CI [-0.90; -0.09]; 5-factor: aMD = -0.50, 95% CI = [-0.91; -0.08]), higher severity of excitement dimension (aMD = 0.16, 95% CI = [0.03; 0.28]). No association was found between cannabis use and disorganization (aMD = -0.13, 95% CI = [-0.42; 0.17]) or depression (aMD = -0.14, 95% CI = [-0.34; 0.06]).

Interpretation

No causal relationship can be inferred from the current results. The findings could be in favor of both a detrimental and beneficial effect of cannabis on positive and negative symptoms, respectively. Longitudinal designs are needed to understand the role of cannabis is this association. The reported effect sizes are small and CIs are wide, the interpretation of findings should be taken with caution.

Funding

This research did not receive any specific grant or funding. Primary financial support for authors was provided by Le Vinatier Psychiatric Hospital.

Alcohol drinking in male patients with chronic schizophrenia: prevalence and its relationship to clinical symptoms

Background

It is common practice to associate schizophrenia (SCZ) patients with substance use. The most commonly used substances in China are tobacco and alcohol. However, few studies have focused on alcohol consumption itself in patients with SCZ. Thus the purpose of this study was to detect the prevalence of alcohol use and associated clinical factors in Chinese patients with SCZ.

Methods

A total of 616 male inpatients who met the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) criteria for SCZ participated in this study. A detailed questionnaire, including data on alcohol consumption was used to collect demographic and clinical information on all patients. The five-factor model of the positive and negative syndrome scale (PANSS) was adopted to assess psychiatric symptoms.

Results

In this study, 31.49% of SCZ inpatients had a history of alcohol use, and 82.9% of these patients abstained from alcohol use after the onset of SCZ. Compared to nondrinkers, patients who drank were more likely to smoke (p = 0.004), more likely to have suicide attempts (p = 0.002) and suicidal ideation (p = 0.001), more severe positive (p < 0.001) and depressive symptoms (p = 0.034), but less severe negative symptoms (p = 0.04).

Conclusion

These findings suggest that alcohol use is common during the lifetime of SCZ patients and that alcohol use may be associated with clinical symptoms in SCZ patients.

Negative symptoms in drug-naive patients with a first-episode psychosis (FEP)

INTRODUCTION

Negative symptoms are nuclear features of schizophrenia that may be present from the onset of the disease. In recent years, it has been described 2 subdomains of negative symptoms: experiential and expressive deficits. The aim of the study is to examine the relationship between negative symptoms and demographic and clinical variables in patients with first-episode psychosis. Also, to explore whether there are differences in the association among these variables and negative symptoms when divided into both subdomains.

MATERIAL AND METHODS

A cross-sectional study was performed in 160 patients (52 females and 108 males) with a diagnosis of a first episode psychosis. A questionnaire was administered to collect demographic and clinical variables.

RESULTS

A backward stepwise linear regressions analysis was performed in order to observe potential associations between demographic and clinical variables and the presence of negative symptoms. All three models are predicted by worse PSP score, a higher CDSS, a higher disorganized factor score and a lower excited factor score. A longer duration of untreated psychosis (DUP) is associated to a higher score in the experiential deficit subdomain only.

CONCLUSIONS

Our work highlights some clinical and phenomenological differences between experiential and expressive deficits. We think that taking into account both subdomains in future studies may lead to more accurate clinical assessment and interventions.

Circadian functioning and quality of life in substance use disorder patients with and without comorbid schizophrenia

Sleep disturbances are strongly linked with mental diseases such as substance use disorder (SUD) or schizophrenia (SZ) which can have a detrimental impact on quality of life (QOL), especially when both disorders are comorbid (dual disorder). In absence of studies about both circadian characteristics and QOL in patients with SUD and comorbid SZ (SUD + SZ), we examined a sample of 155 male under treatment, 75 with SUD + SZ and 80 only with SUD. Circadian functioning was evaluated by chronotype, social jet-lag and sleep quality (using the Pittsburgh Sleep Quality Index, PSQI), while the QOL was obtained by the World Health Organization's Quality of Life Questionnaire (WHOQOL)-BREF. SUD + SZ patients were more evening type than SUD, and this chronotype was linked to polydrug use in total sample and SUD + SZ group. We observed that the comorbidity did not lead to worse sleep quality in the SUD and SUD + SZ patients. QOL was poorer in SUD + SZ patients, who showed a negative association of Physical health, Psychological health and Social relationship with suicide attempts and severity of SZ. Lastly, patients with worse QOL also reported poorer sleep quality suggesting that treatment could include circadian adjustments along with a focused approach to lifestyle improvement.

Alcohol use history increases the likelihood of suicide behavior among male chronic patients with schizophrenia in a Chinese population

AIMS

This study was designed to detect the association between the history of alcohol drinking and suicidality in schizophrenia (SCZ) inpatients in a Chinese population.

METHODS

We recruited 616 male SCZ inpatients and collected demographic and clinical data. Five-factor model of the Positive and Negative Syndrome Scale (PANSS) was used to assess their psychopathological symptoms.

RESULTS

Our results showed that 31.33% of SCZ patients had a history of alcohol drinking. They had higher rates of lifetime suicide attempt and suicidal ideation than those without a history of alcohol drinking. Moreover, patients with a history of drinking were more likely to attempt suicide (14.51% vs. 7.09%; χ²  = 7.70, df = 1, p = 0.006), with an odds ratio (OR) of 2.22 and have suicidal ideation (29.02% vs. 17.49%; χ²  = 9.89, df = 1, p = 0.002), with an OR of 1.93. In addition, patients who used to drink alcohol were more likely to be smokers and had more severe positive and depressive symptoms (all p < 0.05).

CONCLUSIONS

Our study indicates that history of alcohol drinking may increase the prevalence of lifetime suicide attempt and suicidal ideation in male patients with chronic SCZ. Moreover, the history of alcohol drinking may be associated with some demographic data and clinical symptoms.

Neuromodulation to Treat Substance Use Disorders in People With Schizophrenia and Other Psychoses: A Systematic Review

BACKGROUND

Substance use disorders (SUDs) are a common yet poorly studied comorbidity in individuals with psychotic disorders. The co-occurrence of the two complicates recovery and interferes with pharmacological and behavioral treatment response and adherence. Recently, researchers have been exploring both invasive and non-invasive neuromodulation techniques as potential treatment methods for SUDs. We review the evidence that neuromodulation may reduce substance craving and consumption in individuals with schizophrenia.

METHODS

A comprehensive literature search of PubMed, MEDLINE, and PsycINFO databases was conducted (N = 1,432). Of these, we identified seven studies examining the effects of repetitive transcranial magnetic stimulation (rTMS) and two studies using transcranial direct current stimulation (tDCS) on drug consumption and craving in schizophrenia or schizoaffective disorders.

RESULTS

Despite the limited number of studies in this area, the evidence suggests that rTMS to the dorsolateral prefrontal cortex (DLPFC) may reduce cannabis and tobacco use in patients with schizophrenia and schizoaffective disorder. Findings with tDCS, however, were inconclusive.

DISCUSSION

Our systematic review suggests that rTMS applied to DLPFC is a safe and promising therapeutic technique for the management of comorbid schizophrenia and SUDs, with the majority of the evidence in tobacco use disorder. However, there was substantial heterogeneity in study methods, underscoring the need to optimize stimulation parameters (e.g., frequency, duration, and target regions). Larger clinical trials are needed to establish the efficacy of rTMS in reducing drug consumption and craving in psychotic patients, ideally in comparison to existing pharmacological and behavioral interventions.

Exploring the relationship between recency and frequency of cannabis use and diminished expression and apathy as two dimensions of negative symptoms in first episode psychosis. A one-year follow-up study

The association between cannabis use and negative symptoms remains unclear because of inconsistent results in existing studies. In this study we aimed to investigate the association between different aspects of cannabis use and 1) diminished expression and 2) apathy as a two-dimensional model of negative symptoms in a sample of 460 participants with first-episode psychosis. Data were collected on relevant clinical and demographic factors including diagnostics and habits of drug use at baseline, with a follow-up assessment after 12-months. We found an association between the frequency of cannabis use two years prior to baseline and the severity of diminished expression and apathy at baseline, while only the association to diminished expression held after controlling for potential clinical and demographic confounders. Frequency of cannabis use at baseline also had a significant effect on the development of diminished expression over the 12-month follow-up period. In conclusion, this study suggests that the frequency of cannabis use contributes to the severity of diminished expression at baseline, and to the progression of diminished expression after 12-months follow-up. Our findings also imply a dose-response relationship between frequency of use and severity of symptoms and add evidence to an association between cannabis use and negative symptoms.

Gender differences in clinical presentation and illicit substance use during first episode psychosis: a natural language processing, electronic case register study

OBJECTIVE

To determine whether gender differences in symptom presentation at first episode psychosis (FEP) remain even when controlling for substance use, age and ethnicity, using natural language processing applied to electronic health records (EHRs).

DESIGN, SETTING AND PARTICIPANTS

Data were extracted from EHRs of 3350 people (62% male patients) who had presented to the South London and Maudsley NHS Trust with a FEP between 1 April 2007 and 31 March 2017. Logistic regression was used to examine gender differences in the presentation of positive, negative, depressive, mania and disorganisation symptoms.

EXPOSURES FOR OBSERVATIONAL STUDIES

Gender (male vs female).

MAIN OUTCOMES AND MEASURES

Presence of positive, negative, depressive, mania and disorganisation symptoms at initial clinical presentation.

RESULTS

Eight symptoms were significantly more prevalent in men (poverty of thought, negative symptoms, social withdrawal, poverty of speech, aggression, grandiosity, paranoia and agitation). Conversely, tearfulness, low energy, reduced appetite, low mood, pressured speech, mood instability, flight of ideas, guilt, mutism, insomnia, poor concentration, tangentiality and elation were more prevalent in women than men. Negative symptoms were more common among men (OR 1.85, 95% CI 1.33 to 2.62) and depressive and manic symptoms more common among women (OR 0.30, 95% CI 0.26 to 0.35). After adjustment for illicit substance use, the strength of associations between gender and negative, manic and depression symptoms increased, whereas gender differences in aggression, agitation, paranoia and grandiosity became insignificant.

CONCLUSIONS

There are clear gender differences in the clinical presentation of FEP. Our findings suggest that gender can have a substantial influence on the nature of clinical presentation in people with psychosis, and that this is only partly explained by exposure to illicit substance use.

Prevalence of Severe Mental Illness Dual Diagnosis Among Inpatients in a Psychiatric Hospital in Malaysia

The aim of this study was to determine the prevalence of alcohol or non-alcohol substance use dual diagnosis among inpatients with severe mental illness in a psychiatric institution in Malaysia. In addition, this study aimed to determine adverse outcomes between dual diagnosis versus single diagnosis. Methods: This was a cross-sectional study conducted in the inpatient ward using the Mini-International Neuropsychiatric Interview (MINI) to establish the diagnosis of severe mental illness and to screen for alcohol or non-alcohol substance use disorder comorbidity. Outcomes and severity of different domains among severe mental illness patients were assessed using the Addiction Severity Index (ASI). Results: Out of 152 patients who participated in this study, 51.3% (n = 78) had comorbid alcohol use disorder, and 29.6% (n = 45) had non-alcohol substance use disorder. Males with Kadazan ethnicity with severe mental illness and alcohol use disorder had a higher risk of having comorbid non-alcohol substance use disorder. Similarly, male Kadazan patients with severe mental illness and non-alcohol substance use disorder had a higher risk of having a comorbid alcohol use disorder. Dual diagnosis patients with alcohol and non-alcohol substance use disorder had higher rates of hospitalizations (p < .001 and p = .001). Family and social relationships were affected among the alcohol use disorder group as shown by the higher composite score for family status (FCOMP; p < .001). This group also showed more severe psychiatric status, as the composite score for psychiatric status (PCOMP) was high (p = .004). Suicidality was higher among patients with alcohol use disorder and severe mental illness (p < .001). Conclusions: The prevalence of severe mental illness dual diagnosis was high in this study with poorer outcomes, higher rates of admissions, and risk of suicidality. This highlights the importance of provisions for a more holistic treatment approach among patients with dual diagnosis.

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.

The prevalence and clinical correlates of substance use disorders in patients with psychotic disorders from an Upper-Middle-Income Country

Background

Substance use disorders (SUDs) occur frequently in patients with psychotic disorders and have been associated with various demographic and clinical correlates. There is an absence of research on the prevalence and clinical correlates of SUDs in psychotic disorders in low-and-middle-income countries (LMICs).

Aim

We aimed to determine the prevalence and correlates of SUDs in psychotic disorders.

Setting

Patients attending a large secondary-level psychiatric hospital in Cape Town South Africa.

Methods

We used the Structured Clinical Interview for DSM-IV (SCID-I) to determine psychiatric and substance use diagnoses, depressive, anxiety, obsessive-compulsive and post-traumatic symptoms. We used logistic regression models to determine significant predictors of SUDs.

Results

In total sample (N = 248), 55.6% of participants had any SUD, 34.3% had cannabis use disorders, 30.6% alcohol use disorders, 27.4% methamphetamine use disorders, 10.4% methaqualone use disorders and 4.8% had other SUDs. There were significant associations with male sex for most SUDs, with younger age and Coloured ethnicity for methamphetamine use disorders, and with lower educational attainment for cannabis use disorders. Anxiety symptoms and suicide attempts were significantly associated with alcohol use disorders; a diagnosis of a substance induced psychosis with cannabis and methamphetamine use disorders. Across most SUDs legal problems and criminal involvement were significantly increased.

Conclusion

This study found a high prevalence and wide distribution of SUDs in patients with psychotic disorders, consistent with previous work from high income countries. Given clinical correlates, in individuals with psychotic disorders and SUDs it is important to assess anxiety symptoms, suicidality and criminal involvement.

From apathy to addiction: Insights from neurology and psychiatry

The tendency to engage in addictive behaviors has long been tied to the actions of the dopamine system. Early theories were based on the fact that all addictive drugs and behaviors (such as gambling) increase dopamine levels in the striatum, and the evidence that dopamine signaled reward or reward prediction error. However, with a changing emphasis of addiction away from purely pharmacological models that emphasize tolerance and withdrawal, towards one of behavioral dyscontrol, is there still a place for abnormal dopamine signaling in addiction? Here we recast the dopamine theory of addiction based on the idea that tonic dopamine may index a continuous phenotype that goes from apathy to impulsivity and compulsivity. Higher tonic dopamine signaling would make individuals vulnerable to drug reinforcement and cue-induced craving. We relate this to computational models of dopamine signaling, and review clinical and neuroimaging evidence from Parkinson's Disease, schizophrenia and bipolar disorder in support of this model.

Psychiatric Hospitalizations of Chronic Psychotic Disorder Patients With and Without Dual Diagnosis, Israel, 1963-2016

Objective: A significant proportion of patients with severe mental illness also experience substance use disorder. For these dual diagnosis (DD) patients, treatment is more complicated and prognosis is worse. Despite the introduction of the Community Rehabilitation of Persons With Mental Health Disability Law in 2000 and ongoing national mental health reforms, psychiatric services in Israel are not meeting the needs of an increasing number of DD patients. This study examines, for the first time in Israel, the prevalence of DD and patterns of psychiatric hospitalizations of chronic psychotic disorder patients with and without substance use disorder. Methods: The National Psychiatric Case Registry provided data on 18,684 persons with schizophrenia/schizoaffective disorders, aged 18-65, with a psychiatric hospitalization during the period 1963-2016 (with at least one hospitalization in 2010-15). Patients were considered as having DD if their substance use disorder was indicated in at least two, or 20%, of hospitalizations. Regression modeling predicted hospitalization measures (number of hospitalizations, total days hospitalized, length of stay). Results were also analyzed by legal status of admission (voluntary or involuntary; psychiatrist-ordered and court-ordered). Results: One-third of patients with chronic psychotic disorder met DD criteria, with a threefold higher rate among males (37.1%) than females (12.8%). Particularly high rates of DD (nearly 50%) were noted among male immigrants from Ethiopia. Compared with non-substance use disorder patients, DD patients had a significantly younger mean age at first hospitalization and shorter average length of stay per hospitalization but a greater number of hospitalizations and total hospital days (p < .0001 for all comparisons). The associations between DD status and hospitalization characteristics remained significant even after accounting for the effects of confounding factors. Hospitalization characteristics were also associated significantly with sex, population group, age, age at first hospitalization, and country of origin. The rate of court-ordered observation or hospitalization was threefold higher in the DD group. Conclusions: These findings, which broadly align with other countries, reflect a scarcity of outpatient services for DD patients with schizophrenia/schizoaffective disorder and substance use disorder. To achieve long-term mental health improvements, an expansion of community-based integrative treatment and rehabilitation services is needed in Israel.

The influence of substance use on the effectiveness of antipsychotic medication: a prospective, pragmatic study

Background: Psychosis is associated with a high prevalence of substance use, leading to worsened prognosis. Less is known about how comorbid substance abuse may influence the effectiveness of antipsychotic medications. The aim of this study was to compare the effectiveness of second generation antipsychotics in patients with psychosis with and without substance use. Methods: All patients (n = 226) were aged >18 years old had symptom level scores of ≥4 on selected psychosis items on the Positive and Negative Syndrome Scale and met ICD-10 diagnostic criteria for psychosis. Information on substance use was collected based on the Clinician Drug Use Scale. Patients were grouped at baseline according to the presence of substance use, medication history and diagnosis group. Clinical symptoms at baseline and changes at follow-up were assessed with the PANSS. Results: At baseline about 30% of the patients used substances, most frequently cannabis followed by methamphetamine. About half (47%) of the patients had no prior exposure to antipsychotic medication at inclusion. Patients who had consumed substances showed no substantial differences in the PANSS score reduction as a result of antipsychotic medication compared to patients without substance. There were, however, some group differences in relation to pattern of change that were influenced by medication history. Substance use was found to be related to stronger reduction of positive symptoms from week 4 to week 27. Conclusion: Substance use alone did not influence antipsychotic effectiveness in this sample of patients with psychosis.

Hazardous alcohol use in a sample of first episode psychosis patients in Singapore

BACKGROUND

Hazardous alcohol use has often been found to be more prevalent amongst psychiatric outpatients than the general population. Additionally, it has also been associated with poorer outcomes. The study aimed to investigate (1) the prevalence and (2) socio-demographic and clinical correlates of hazardous alcohol use, as well as (3) the relationship between hazardous alcohol use and quality of life in an outpatient sample with First Episode Psychosis (FEP) in Singapore.

METHODS

Baseline data (N = 280) was extracted from a longitudinal study investigating smoking and alcohol use amongst outpatients with FEP in a psychiatric hospital. Information on socio-demographics, hazardous alcohol use, and quality of life was collected through a self-report survey. Hazardous alcohol use was ascertained by total scores of 8 or higher on the Alcohol Use Disorders Identification Test (AUDIT). Data was analysed using logistic regression and linear regression analyses.

RESULTS

The prevalence of hazardous alcohol use over the past 12-month period was 12.9%. Those who had never smoked in their lifetime (vs current smokers) and those with a diagnosis of brief psychotic disorder (vs schizophrenia spectrum disorders) were found to have significantly lower odds of hazardous alcohol use. Hazardous alcohol use was also associated with lower negative symptom scores. Lastly, hazardous alcohol use was found to significantly predict lower scores on the physical health, social relationship and environment domains of quality of life.

CONCLUSIONS

The association between hazardous alcohol use and lower negative symptom scores is a surprising finding that needs to be further explored. The significant impact of hazardous alcohol use in reductions in quality of life suggests that early screening and interventions could benefit patients with hazardous alcohol use and comorbid psychosis.

Factors Affecting the Management of Somatic Comorbidity in Tunisian Patients with Schizophrenia

Schizophrenia is often accompanied by somatic comorbidities, which make the management challenge of such patients more difficult. In this study, we proposed to identify the sociodemographic and clinical factors correlating with somatic comorbidities in patients with schizophrenia to facilitate screening and prevention. It was a retrospective descriptive study of 78 schizophrenia patients in clinical remission and followed in outpatient psychiatry. In addition to the acquired records, other data were provided by the clinical and biological examinations performed for each patient. The evaluation of the therapeutic adherence was carried out using the Drug Attitude Inventory (DAI).Seventy-six patients (97.4%) had somatic comorbidities with a mean of 3.83 (± 1.81). This number increased significantly in males, older patients, couples, urban patients, and those receiving a combination therapy. According to a multivariate study, the four predictors of an increased risk of comorbidities were age, use of psychoactive substances, waist size and therapeutic adherence.Our findings focus on somatic comorbidities risk in schizophrenia patients, requiring particular vigilance in their follow-up, and suggest some modifiable clinical factors that might be a preferred target for reducing or preventing the occurrence of such disorders.

Impact of tobacco, alcohol and cannabis use on treatment outcomes among patients experiencing first episode psychosis: Data from the national RAISE-ETP study

AIM

The primary aim of this study was to examine the effect of recent tobacco, alcohol and cannabis use on treatment outcomes among participants experiencing first episode psychosis (FEP).

METHODS

Secondary data analyses were conducted on 404 participants enrolled in the Recovery After an Initial Schizophrenia Episode-Early Treatment Program (RAISE-ETP) study. RAISE-ETP investigated the effectiveness of a coordinated specialty care (CSC) intervention for FEP in community mental health agencies in the United States. Generalized estimating equations were used to examine whether recent tobacco smoking, alcohol, and cannabis use at baseline were associated with illness severity, number of antipsychotic pills missed, psychiatric symptoms and quality of life during the 24-month treatment period, after controlling for duration of untreated psychosis and treatment group.

RESULTS

At baseline, roughly 50% (n = 209) of participants reported recent tobacco, 28% (n = 113) alcohol and 24% (n = 95) cannabis use. Tobacco smokers had higher levels of illness severity (β = .24; P < .005), a higher number of missed pills (β = 2.89; P < .05), higher psychiatric symptoms and lower quality of life during treatment relative to non-smokers. Alcohol users had a higher number of missed pills (β = 3.16; P < .05) during treatment and cannabis users had higher levels of illness severity (β = .18; P < .05) and positive symptoms (β = 1.56; P < .05) relative to non-users.

CONCLUSIONS

Tobacco, alcohol and cannabis use are common in youth seeking treatment for FEP. Tobacco smoking was associated with more negative clinical outcomes. These findings have implications for including interventions targeting these areas of substance use within current CSC models.

Prevalence of comorbid substance use in schizophrenia spectrum disorders in community and clinical settings, 1990-2017: Systematic review and meta-analysis

BACKGROUND

Comorbidity is highly prevalent between substance use disorders (SUDs) and schizophrenia. This systematic review and meta-analysis estimated prevalence rates of SUDs in epidemiological and treatment-seeking patients diagnosed with schizophrenia or first episode psychosis.

METHODS

A literature search of Medline, EMBASE, PsycINFO and CINAHL databases was conducted from 1990 to 2017 inclusive. Prevalence of co-morbid SUDs and schizophrenia were extracted and odds ratios (ORs) were calculated using random effects meta-analysis. Combining like studies was dictated how authors reported substance use.

RESULTS

There were 123 included articles with a total sample size of 165,811 subjects that yielded six epidemiological studies, 11 national or state case-registry studies, 20 large cohort studies and 86 clinical studies using in- or out-patient samples. The prevalence of any SUD was 41.7%, followed by illicit drugs (27.5%), cannabis (26.2%), alcohol (24.3%) and stimulant use (7.3%). Meta-analysis showed the pooled variance of any SUD in males was 48% which was significantly higher than that for females with schizophrenia (22.1%, OR 3.43, 95% CI 3.01, 3.92). Patients with SUD had an earlier age of onset of schizophrenia. Meta-regression showed prevalence increased over time for illicit drugs but not for other substances, including alcohol.

CONCLUSIONS

The meta-analysis revealed that SUDs in schizophrenia is highly prevalent and rates have not changed over time. This indicates SUD are difficult to treat in this patient population and there is an urgent need for more informative studies to help develop better prevention, detection and treatment of SUDs in persons with schizophrenia and co-morbid disorders.

Impact of comorbid cannabis use on outcome in first episode psychosis

AIM

Comorbid cannabis abuse is common in patients with early psychosis. Little is known about the effect of stopping cannabis use on positive, negative and depressive symptoms. Few studies have controlled for multiple substance use that may mask the specific role that cannabis plays in symptom outcomes. The aim of this study was to investigate whether course and level of cannabis use negatively impacted early psychosis patient symptom profiles (positive, negative and depressive symptoms) over 24 months.

METHODS

One hundred and ninety-two patients admitted to an early psychosis intervention programme in a naturalistic setting were followed across three time periods: initial presentation, 12 and 24 months. Patients' clinical characteristics (substance use, positive/negative symptoms and depressive symptoms) were assessed at each time period.

RESULTS

There were no significant associations found between cannabis abuse and positive and negative symptoms. Continuation and discontinuation of cannabis use were not significant for cannabis or any other substance when compared to positive and negative symptoms. There was a significant interaction between cannabis and alcohol for depressive symptoms, where depressive symptoms were significantly higher in patients who abused cannabis without co-occurring alcohol abuse when compared to non-cannabis using patients.

CONCLUSION

The current study findings indicate a complex interaction between cannabis and alcohol use in a sample of early psychosis patients across 24 months. More research is needed into the association between ceasing cannabis use and long-term outcome for early psychosis patients. Of particular importance is the interaction between level of cannabis and alcohol use as it is related to symptom outcome in early psychosis patients.

Clinical characteristics of primary psychotic disorders with concurrent substance abuse and substance-induced psychotic disorders: A systematic review

BACKGROUND

Distinguishing between a primary psychotic disorder with concurrent substance abuse (PPD+SA) and a substance-induced psychotic disorder (SIPD) can be diagnostically challenging. We aimed to determine if these two diagnoses are clinically distinct, particularly in relation to psychopathology. In addition, we aimed to examine the specific clinical features of cannabis-induced psychotic disorder (CIPD) as compared to primary psychotic disorder with concurrent cannabis abuse (PPD+CA) and also to SIPD associated with any substance.

METHODS

A systematic review of SIPD literature using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Using strict inclusion criteria, a total of six studies examining SIPD were included in the review (two of which only considered psychosis induced by cannabis alone). The findings did not reveal many consistent differences in psychopathology. However, we did find that that compared to PPD+SA, individuals with SIPD have a weaker family history of psychotic disorder; a greater degree of insight; fewer positive symptoms and fewer negative symptoms; more depression (only in CIPD) and more anxiety.

CONCLUSION

There remains a striking paucity of information on the psychopathology, clinical characteristics and outcome of SIPD. Our review highlights the need for further research in this area.

Meta-analysis of neurocognition in young psychosis patients with current cannabis use

OBJECTIVE

Adult psychosis patients (i.e. over the age of 25 years) who are also lifetime cannabis users (CANN±) appear to exhibit superior cognition compared to never-using patients (CANN-). The objective of this meta-analysis was to evaluate the cognitive differences between CANN- and patients who currently use cannabis (CANN+) (i.e. during the CANN± patients' cannabis-using stage). Specifically, focusing on young patients under the age of 25 years, the typical stage of both psychosis- and cannabis-onset.

METHOD

Of the 308 studies identified through database searches and secondary referencing, 14 compared neurocognition of CANN+ and CANN- in young people with psychotic disorders (mean age between 15 and 45 years). Effect sizes were extracted using neurocognitive test performance between CANN+ and CANN- and random effects modelling was conducted on pooled ES and moderator analyses.

RESULTS

CANN+ performed worse on several cognitive domains (i.e. premorbid IQ, current IQ, verbal learning, verbal working memory, motor inhibition) compared to CANN-. The association between age and performance in CANN+ cognition was varied, with older age predictive of worse performance in processing speed, sustained attention, verbal memory, and better performance in verbal learning and very fluency. Of note, CANN+ outperformed CANN- in tests of conceptual set-shifting.

CONCLUSION

These results are consistent with previous findings indicating that CANN+ demonstrate poorer neurocognition than CANN-; and that this is exacerbated with increasing age. Our findings demonstrate significant cognitive differences between patients with CANN+ versus CANN- even at early-onset psychosis, which could suggest a different underlying mechanism towards psychosis for cannabis users.

Motivation deficits and use of alcohol and illicit drugs among individuals with schizophrenia

This study examined the impact of substance use on intrinsic motivation and evaluated the association between intrinsic motivation and substance use recovery among individuals with schizophrenia. Alcohol and illicit drug use and intrinsic motivation were evaluated at baseline and 6-months for 1434 individuals with schizophrenia from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) using self-rated substance use assessments and a derived motivation measure from the Heinrichs-Carpenter Quality of Life Scale. Results revealed patients had moderate motivation deficits overall and a considerable number were using alcohol or illicit drugs at baseline (n=576; 40.2%). Regression models at baseline showed patients with low levels of motivation had higher odds of substance use and those who were using substances had greater motivation deficits. At 6-months, substance using patients continued to demonstrate greater motivation deficits; however, those with high levels of motivation exhibited a greater reduction in their use of substances. Findings remained significant after adjusting for clinical confounds and were consistent across any substance, alcohol, and cannabis use. Our results emphasize concerns about substance use compounding motivation deficits in schizophrenia, and suggest that disentangling the motivation-substance use relationship in schizophrenia may facilitate efforts aimed at ameliorating these challenges and improving outcomes.

An Integrative Perspective on the Role of Dopamine in Schizophrenia

We propose that schizophrenia involves a combination of decreased phasic dopamine responses for relevant stimuli and increased spontaneous phasic dopamine release. Using insights from computational reinforcement-learning models and basic-science studies of the dopamine system, we show that each of these two disturbances contributes to a specific symptom domain and explains a large set of experimental findings associated with that domain. Reduced phasic responses for relevant stimuli help to explain negative symptoms and provide a unified explanation for the following experimental findings in schizophrenia, most of which have been shown to correlate with negative symptoms: reduced learning from rewards; blunted activation of the ventral striatum, midbrain, and other limbic regions for rewards and positive prediction errors; blunted activation of the ventral striatum during reward anticipation; blunted autonomic responding for relevant stimuli; blunted neural activation for aversive outcomes and aversive prediction errors; reduced willingness to expend effort for rewards; and psychomotor slowing. Increased spontaneous phasic dopamine release helps to explain positive symptoms and provides a unified explanation for the following experimental findings in schizophrenia, most of which have been shown to correlate with positive symptoms: aberrant learning for neutral cues (assessed with behavioral and autonomic responses), and aberrant, increased activation of the ventral striatum, midbrain, and other limbic regions for neutral cues, neutral outcomes, and neutral prediction errors. Taken together, then, these two disturbances explain many findings in schizophrenia. We review evidence supporting their co-occurrence and consider their differential implications for the treatment of positive and negative symptoms.

Premorbid cannabis use is associated with more symptoms and poorer functioning in schizophrenia spectrum disorder

BACKGROUND

Cannabis use disorder is associated with an earlier age at onset and a more severe outcome of schizophrenia spectrum disorders. The role of cannabis use before the onset of illness (premorbid cannabis use) has not been fully investigated. We here examined how amount and type of premorbid cannabis use was associated with the later course of illness including current substance use, symptoms and level of functioning in schizophrenia spectrum disorder.

METHOD

We used a naturalistic sample of patients with DSM-IV schizophrenia spectrum disorders with a comprehensive history of illness and substance use. Data on premorbid substance use was obtained from comprehensive self-report. The relationship to outcome was investigated using regression models that included current substance use and premorbid functioning.

RESULTS

Pre-schizophrenia cannabis use was significantly associated with more severe psychotic symptoms and impaired functioning. Higher levels of premorbid cannabis use were associated with higher levels of current psychotic symptoms. These associations were independent of current substance use and premorbid functioning. Early use of cannabis (age <17 years) was associated with earlier age at onset of psychosis, independently of potential confounders.

CONCLUSIONS

Pre-psychosis cannabis use affects illness outcome in schizophrenia spectrum disorders, and is associated with lower age at onset of psychosis. These findings of independent negative effects of premorbid cannabis use in schizophrenia suggest that a limitation of the general use of cannabis may have beneficial health effects.

[Negative symptoms in schizophrenia and substance-related disorders]

Dual diagnosis of schizophrenia and substance-related disorders is common in psychiatric practice. Epidemiologic studies and report have established that the risk of a substance-related disorder was 4 to 5 times higher in a population of psychiatric patients than in the general population. However, little is known on the reason of this relationship and the treatments required. It's well known that a family history of psychosis is a risk factor of schizophrenia. Similarly a family history of substance use disorders increases the risk of using substances. Because the two disorders often occurred together, it could be hypothesized that a genetic risk factor is common. However, recent studies did not confirm this hypothesis and it seems that their genetic risks factor would be unrelated. Evidence now exists describing the different profiles of patients whether they used substance or not. Concerning negative symptoms clinical studies and meta-analyses have described fewer symptoms in schizophrenia patients with a substance use disorder. Among the different explanations that have been addressed, it seems that a lower capability of obtaining the substance could partly explain this relationship. Perhaps because patients with social withdrawal have more difficulties to find and spend the time required to obtain abused substances. At the opposite some products such as cocaine may relieve some symptoms especially anhedonia and alogia. However the link between substance-related disorders and negative symptoms is weak and decreases in more recent studies, probably because negative symptoms as well as addiction disorders are better characterized. Considering that treating psychiatric symptoms may not always lead to a decrease in the substance-related disorders but that patients who give up substances improve their psychotic symptoms, a therapeutic strategy should be planned for these dual disorders patients combining psychiatry and addiction interventions.

Can symptoms help in differential diagnosis between substance-induced vs independent psychosis in adults with a lifetime diagnosis of cocaine use disorder?

The main goal of this study it is explore the psychopathological differences between IPD and SIPD in a sample of 125 adults with a lifetime diagnosis of cocaine disorder recruited from treatment setting and through street contacts. A secondary analysis of six cross-sectional studies was conducted between 2000 and 2010. SIPD and IPD were diagnosed using the Psychiatric Research Interview for Substance and Mental Disorders (PRISM). 38 subjects (30.4%) were diagnosed with lifetime IPD and 87 (69.6%) with lifetime SIPD. A binomial logistic regression analysis using SIPD as the reference group showed that only previous prison admissions (OR 2.59; 95% CI 1.05, 6.36) and visual hallucinations (OR 5.21; 95% CI 1.54, 17.65) remained significant variables in the group with lifetime SIPD. In the group with lifetime IPD, grandiose delusions (OR 0.19; 95% CI 0.06, 0.60) and disorganized speech (OR 0.16; 95% CI 0.04, 0.61) remained significant. Model predicts the diagnosis of lifetime SIPD with a sensitivity of 80.3% and a specificity of 78.2%. This clinical profile of lifetime SIPD could help distinguish between IPD and SIPD among adults with lifetime diagnosis of cocaine disorder.

Differential effects of sex on substance use between first episode psychosis patients and healthy people

BACKGROUND

Substance use in psychosis is an important field of study given that it can be a risk factor for the development of psychosis and can give rise to psychotic symptoms. Studies of substance use in first episode psychosis patients do not frequently assess non-pathological substance consumption among patients, but rather the prevalence of substance abuse or dependence disorders. Moreover, most of these studies do not address the effects of sex in sufficient depth, and the consumption of caffeine or tobacco, which are two of the most frequently used substances, is often not assessed.

OBJECTIVES

The aim of this study was to compare patterns and quantities of substance use between first episode psychosis patients and healthy controls and between men and women, and explore the potential interactive effects between group (patients or controls) and sex.

METHODS

A total of 158 participants (82 first episode psychosis patients and 76 healthy controls) were included in the study. Both adults and adolescents were included in the study. Frequency and amount of use of caffeine, tobacco, alcohol, cannabis, cocaine, hallucinogens, stimulants, and opiates were gathered.

RESULTS

A significant main effect of sex was found for the frequency of use of tobacco (p=.050). Main effects of group were found for the quantity of tobacco (p<.001) and cannabis (p<.001) consumed, as well as main effects of sex for the quantity of alcohol (p=.003) and cannabis (p=.017) consumed. There were also interaction effects between group and sex for the frequency of use of tobacco (p=.005) and cannabis (p=.009), and for the amount of cannabis consumed (p=.049). Qualitative differences between males and females regarding combined substance use are also reported.

CONCLUSIONS

Among patients, men used tobacco more frequently than women, but this sex difference was not the same for the control group, in which women smoked more often than men. Regarding cannabis, men smoked cannabis more frequently and in larger amounts than women, but only in the patients group, whereas no sex differences for cannabis were found for the controls. Main effects of group and sex for tobacco and alcohol, as well as the lack of differences for the frequency and amount of use of caffeine, are also commented. This is the first study to assess the different effects of sex on substance use in first episode psychosis patients and healthy controls.

Differential effects of childhood trauma and cannabis use disorders in patients suffering from schizophrenia

BACKGROUND

Childhood trauma (CT) and cannabis use are both environmental and modifier risk factors for schizophrenia. However, little is known about how they interact in schizophrenia. We examined the main effect of each of these two environmental factors on the clinical expression of the disease using a large set of variables, and we tested whether and how cannabis and CT interact to influence the course and the presentation of the illness.

METHODS

A sample of 366 patients who met the DSM-IV-TR criteria for schizophrenia was recruited through the FACE-SCZ (Fondamental Advanced Centre of Expertise - Schizophrenia) network. Patients completed a large standardized clinical evaluation including Structured Clinical Interview for DSM Disorders-I (SCID-I), Positive and Negative Symptoms Scale (PANSS), Columbia-Suicide Severity Rating Scale (C-SSRS), Global Assessment of Functioning (GAF), Short-Quality of Life-18 (S-QoL-18), and Medication Adherence Rating Scale (MARS). We assessed CT with the Childhood Trauma Questionnaire and cannabis status with SCID-I.

RESULTS

CT significantly predicted the number of hospitalizations, GAF, and S-QoL-18 scores, as well as the PANSS total, positive, excitement, and emotional distress scores. Cannabis use disorders significantly predicted age of onset, and MARS. There was no significant interaction between CT and cannabis use disorders. However, we found evidence of a correlation between these two risk factors.

CONCLUSIONS

CT and cannabis both have differential deleterious effects on clinical and functional outcomes in patients with schizophrenia. Our results highlight the need to systematically assess the presence of these risk factors and adopt suitable therapeutic interventions.

Psychosocial functioning, quality of life and clinical correlates of comorbid alcohol and drug dependence syndromes in people with schizophrenia across Europe

Little is known about the correlates of comorbid drug and alcohol dependence in people with schizophrenia outside the USA. We tested hypotheses that dependence on alcohol/drugs would be associated with more severe symptoms, and poorer psychosocial functioning and quality of life. The EuroSC Cohort study (N=1204), based in France, Germany and the UK, used semi-structured clinical interviews for diagnoses, and standardized tools to assess correlates. We used mixed models to compare outcomes between past-year comorbid dependence on alcohol/drugs, controlling for covariates and modelling both subject and country-level effects. Participants dependent on alcohol or drugs had fewer negative symptoms on PANSS than their non-dependent counterparts. However, those dependent on alcohol scored higher on PANSS general psychopathology than those who were not, or dependent only on drugs. People with schizophrenia dependent on drugs had poorer quality of life, more extrapyramidal side effects, and scored worse on Global Assessment of Functioning (GAF) than those without dependence. People with alcohol dependence reported more reasons for non-compliance with medication, and poorer functioning on GAF, though not on Global Assessment of Relational Functioning. In people with schizophrenia, comorbid dependence on alcohol or drugs is associated with impaired clinical and psychosocial adjustment, and poorer quality of life.

Prevalence of Substance Use in Patients Diagnosed with Schizophrenia

INTRODUCTION

Substance abuse among schizophrenic patients is a growing clinical concern. Substance use disorders and their effects on the course of schizophrenia have made the identification and treatment of schizophrenic patients a high priority. This study aimed to investigate the prevalence of substance use, preferred types of substances, sociodemographic characteristics and clinical features of schizophrenia, and substance use impact in schizophrenic patients.

METHODS

Hundred patients who were consecutively admitted to the psychiatry clinic and were diagnosed with schizophrenia according to the DSM-IV criteria were enrolled in this study. Individual interviews were conducted during the patients. In order to evaluate substance abuse disorder (SAD) as per DSM-IV criteria, the substance use disorder section of the structured clinical interview for DSM disorders-II (SCID-II) form was used. In addition, the following were applied to schizophren-ic patients: sociodemographic data form, medical history form, Brief Disability Questionnaire (BDQ), UKU Side Effect Rating Scale (UKUSERS), Insight Rating Scale (IRS), Alcohol Use Dis-orders Identification Test (AUDIT), Fagerstrom Nicotine Dependence Test (FNDT), Global As-sessment of Functioning Scale (GAF), Scale for the Assessment of Positive Symptoms (SAPS), Scale for the Assessment of Negative Symptoms (SANS), and Calgary Depression Scale (CDS).

RESULTS

Schizophrenia and alcohol and drug use were more common in males, and younger age was found to have no association with substance use. Unemployment, low education levels, rural survival rates, age at disease onset, the doctor first age of the applicant, the first inpatient years, legal issues, harm caused by others and suicidal behavior, SAPS, SANS, CDS received from their scores significant difference was detected. Schizophrenic patients with substance use had higher side effects of drugs, disability, and psychopathology scores than schizophrenic patients without substance use. The functioning of schizophrenic patients with substance use was worse, and the total length of stay was longer. Nicotine, alcohol, biperiden, cannabis, and volatile substances were the preferred materials most commonly used by schizophrenic patients.

CONCLUSION

In our country, limited research has been conducted on the prevalence of substance use in schizophrenic patients. Therefore, we believe that this study will contribute to the literature on the subject. More sample groups and first-episode patients as well as follow-up studies will contribute to a better understanding of the effect of substance use on the clinical course of schizophrenia.

Cannabis use and family history in adolescent first episode psychosis in Durban, South Africa

OBJECTIVES

To investigate the clinical correlates of cannabis use in adolescents with first episode psychosis (FEP).

METHODS

Inpatient psychiatric records provided demographic, lifetime cannabis use, family history of mental illness, and clinical data on 45 FEP adolescents, aged 12-18 years, admitted to a psychiatric unit in Durban, KwaZulu-Natal, South Africa, over a 2-year period.

RESULTS

Thirty-one (68.8%) of the 45 FEP adolescents reported a history of lifetime cannabis use. The age of FEP presentation and pre-diagnosis symptom duration was not significantly different in cannabis users versus non cannabis users. Of the 15/43 (34.8%) FEP patients with family history of mental illness, 10 had a history of cannabis use. The 26 (57.8%) schizophrenia spectrum disorder patients did not differ significantly from the 19 (42.2%) with other psychoses in terms of cannabis use and family history of mental illness. They were, however, significantly younger at age of presentation and had a significantly longer duration of pre-diagnosis symptoms.

CONCLUSIONS

These preliminary findings suggest a high prevalence of cannabis use in adolescents with FEP and highlight the public health concern of addressing substance abuse in the adolescent population.

A clinical comparison of schizophrenia with and without pre-onset cannabis use disorder: a retrospective cohort study using categorical and dimensional approaches

BACKGROUND

A high prevalence of cannabis use disorder has been reported in subjects suffering from schizophrenia, fuelling intense debate about whether schizophrenia with pre-onset cannabis use disorder may be a distinct entity with specific features or whether cannabis use disorder can precipitate schizophrenia in genetically vulnerable subjects.

METHODS

We retrospectively assessed schizophrenia subjects with and without pre-onset cannabis use disorder on the basis of their clinical features, assessed categorically and dimensionally with the operational criteria checklist for psychotic illnesses (OCCPI). We also investigated whether the two groups could be differentiated on the basis of a history of psychiatric disorders in first-degree relatives. A principal component factor analysis of the OCCPI items was used to identify specific symptom dimensions. The relationships between symptom dimensions and cannabis status were analysed by point-biserial correlation analysis to control for sex and age at time of the assessment and illness duration.

RESULTS

One hundred and seventy-one subjects with a diagnosis of schizophrenia were included. Among them, forty-one patients (18.2 % of the sample) had a cannabis use disorder before or at the time of the onset of schizophrenia. We found similar results in symptoms patterns or family history between patients with and without pre-onset cannabis use disorder.

CONCLUSIONS

Our results clearly argue against cannabis-associated schizophrenia being a relevant distinct clinical entity of schizophrenia with specific features.

Cognitive Enhancement Therapy Improves Frontolimbic Regulation of Emotion in Alcohol and/or Cannabis Misusing Schizophrenia: A Preliminary Study

Individuals with schizophrenia who misuse substances are burdened with impairments in emotion regulation. Cognitive enhancement therapy (CET) may address these problems by enhancing prefrontal brain function. A small sample of outpatients with schizophrenia and alcohol and/or cannabis substance use problems participating in an 18-month randomized trial of CET (n = 10) or usual care (n = 4) completed posttreatment functional neuroimaging using an emotion regulation task. General linear models explored CET effects on brain activity in emotional neurocircuitry. Individuals treated with CET had significantly greater activation in broad regions of the prefrontal cortex, limbic, and striatal systems implicated in emotion regulation compared to usual care. Differential activation favoring CET in prefrontal regions and the insula mediated behavioral improvements in emotional processing. Our data lend preliminary support of CET effects on neuroplasticity in frontolimbic and striatal circuitries, which mediate emotion regulation in people with schizophrenia and comorbid substance misuse problems.

Cognitive changes in patients with acute phase psychosis--effects of illicit drug use

Illicit drug use may influence cognition in non-affective psychosis. Previous studies have shown better cognition in psychosis with illicit drug use as compared to psychosis only. Possibly, illicit drug using patients have more transient drug-related cognitive deficits. Thus, the aim of the present study was to examine cognitive change the first weeks after admission to a psychiatric emergency ward, expecting more cognitive improvement at follow-up in the illicit drug group as compared to psychosis only. Patients with acute non-affective psychosis with (26%) and without illicit drug use were examined at baseline (n=123) and follow-up (n=67), with alternative forms of the Repeatable Battery for the Assessment of Neuropsychological Status. Latent Growth Curve models, controlling for cognition at baseline and age differences between the groups, were used to analyze cognitive change. The illicit drug using patients showed the largest improvement in cognition, especially among the youngest patients. Younger patients with non-affective psychosis and illicit drug use showed more cognitive improvement the first weeks after acute psychosis as compared to psychosis only. This suggests that the illicit drug users constitute a sub-group with less stable cognitive deficits and less cognitive vulnerability.

Psychose et toxicomanie : le cimetière des évidences

L’objectif de cet article est d’évaluer la qualité des évidences produites par les 25 méta-analyses publiées dans le domaine de la comorbidité entre la psychose et la toxicomanie. L’évidence suggère que le cannabis serait un facteur de risque dans le développement de la psychose. Cette relation est toutefois faible, et ses implications demeurent équivoques. La prévalence de la consommation de tabac, d’alcool et de cannabis est élevée dans la psychose, mais elle semble surestimée, puisqu’inférée à partir d’études cliniques et non pas populationnelles. La toxicomanie est associée à une exacerbation des symptômes positifs et dépressifs de la schizophrénie, mais cette observation est basée sur des études transversales, et non pas longitudinales. Une forte association existe entre la toxicomanie et la violence dans la psychose, mais celle-ci n’est pas pondérée en fonction de divers facteurs confondants. Les effets de la toxicomanie sur la cognition dans la schizophrénie sont hétérogènes. Le bupropion et la varénicline augmentent les taux de cessation tabagique dans la schizophrénie, mais cette observation est basée sur un petit nombre d’études. Enfin, les traitements intégrés ne semblent pas supérieurs aux traitements habituels offerts à cette population comorbide. Le champ de la comorbidité demeure certainement un immense défi pour la médecine fondée sur les évidences.

The Cannabis Pathway to Non-Affective Psychosis may Reflect Less Neurobiological Vulnerability

There is a high prevalence of cannabis use reported in non-affective psychosis. Early prospective longitudinal studies conclude that cannabis use is a risk factor for psychosis, and neurochemical studies on cannabis have suggested potential mechanisms for this effect. Recent advances in the field of neuroscience and genetics may have important implications for our understanding of this relationship. Importantly, we need to better understand the vulnerability × cannabis interaction to shed light on the mediators of cannabis as a risk factor for psychosis. Thus, the present study reviews recent literature on several variables relevant for understanding the relationship between cannabis and psychosis, including age of onset, cognition, brain functioning, family history, genetics, and neurological soft signs (NSS) in non-affective psychosis. Compared with non-using non-affective psychosis, the present review shows that there seem to be fewer stable cognitive deficits in patients with cannabis use and psychosis, in addition to fewer NSS and possibly more normalized brain functioning, indicating less neurobiological vulnerability for psychosis. There are, however, some familiar and genetic vulnerabilities present in the cannabis psychosis group, which may influence the cannabis pathway to psychosis by increasing sensitivity to cannabis. Furthermore, an earlier age of onset suggests a different pathway to psychosis in the cannabis-using patients. Two alternative vulnerability models are presented to integrate these seemingly paradoxical findings.

Systematic meta-analysis of outcomes associated with psychosis and co-morbid substance use

OBJECTIVE

To compare the symptoms and social function of patients with psychosis and current substance use to those with psychosis and no history of substance use.

METHOD

The databases EMBASE, MEDLINE and PsycINFO were searched for peer-reviewed publications in English that reported the characteristics of patients with psychotic illness who were current substance users and those who had never used substances. The searches yielded 22 articles that met the inclusion criteria. Meta-analysis was used to compare four key outcome variables: positive symptoms, negative symptoms, depression and social function - and three secondary outcomes: violence, self-harm and hospital admissions.

RESULTS

Current substance-using patients were significantly younger than non-substance-using patients and were more likely to be male, but did not differ in age at onset of psychosis or in their level of education. Current substance users had higher ratings of positive symptoms and were more likely to have a history of violence. Older studies reported a stronger association between current substance use and positive symptoms than more recently published studies. Current substance users did not differ from non-users on measurements of negative symptoms, depressive symptoms, social function, self-harm, or the number of hospital admissions.

CONCLUSION

Current substance users with psychosis may have more severe positive symptoms than patients who have never used substances, but this result should be interpreted with caution because of demographic differences between substance users and non-substance users.

Comorbid substance use disorder in schizophrenia: a selective overview of neurobiological and cognitive underpinnings

Although individuals with schizophrenia show a lifetime prevalence of 50% for suffering from a comorbid substance use disorder, substance abuse usually represents an exclusion criterion for studies on schizophrenia. This implies that surprisingly little is known about a large group of patients who are particularly difficult to treat. The aim of the present work is to provide a brief and non-exhaustive overview of the current knowledgebase about neurobiological and cognitive underpinnings for dual diagnosis schizophrenia patients. Studies published within the last 20 years were considered using computerized search engines. The focus was on nicotine, caffeine, alcohol, cannabis and cocaine being among the most common substances of abuse. All drugs of abuse target dopaminergic, glutamatergic and GABAergic transmission which are also involved in the pathophysiology of schizophrenia. Current literature suggests that neurocognitive function might beless disrupted in substance-abusing compared to non-abusing schizophrenia patients, but in particular the neuroimaging database on this topic is sparse. Detrimental effects on brain structure and function were shown for patients for whom alcohol is the main substance of abuse. It is as yet unclear whether this finding might be an artifact of age differences of patient subgroups with different substance abuse patterns. More research is warranted on the specific neurocognitive underpinnings of schizophrenia patients abusing distinct psychoactive substances. Treatment programs might either benefit from preserved cognitive function as a resource or specifically target cognitive impairment in different subgroups of addicted schizophrenia patients.

Do former substance users with psychosis differ in their symptoms or function from non-substance users? A systematic meta-analysis

OBJECTIVE

To compare the symptoms and function of patients with psychosis who have ceased using substances to those who have psychosis but do not have a history of substance use.

METHOD

The databases EMBASE, MEDLINE and PsycINFO were searched for peer-reviewed publications in English reporting the characteristics of patients with psychotic illness who had stopped using substances and those who had never used substances. The searches yielded 20 articles that met the inclusion criteria. Four key outcome variables - positive symptoms, negative symptoms, depression and global function - and four other outcome measures reported in five or more studies were examined using meta-analysis.

RESULTS

Former substance-using patients were significantly younger than non-substance-using patients and were more likely to be male, but did not differ in age at onset of psychosis or in their level of education. There were no significant differences between former substance users and non-substance users in ratings of positive symptoms, negative symptoms, depression or global function. Among first-episode patients there was a trend towards former substance users having less severe depressive symptoms than non-substance users. In contrast, among non-first-episode patients, former substance users had significantly more depressive symptoms than non-substance users. In studies rated as being of higher quality, former substance users had significantly less severe positive symptoms than non-substance users.

CONCLUSION

The absence of significant differences between the two groups suggests that a history of substance use is not a poor prognostic indicator for patients who are able to stop using substances.

Cannabis withdrawal in chronic cannabis users with schizophrenia

BACKGROUND

Chronic users of cannabis often report withdrawal symptoms after abstinence from use, but little is known about cannabis withdrawal in people with schizophrenia.

METHODS

Cannabis use patterns and withdrawal symptoms in adults with schizophrenia who had at least weekly cannabis use before attempting to quit without formal treatment were assessed with the Marijuana Quit Questionnaire (MJQQ), a 176-item, semi-structured questionnaire.

RESULTS

120 participants, predominantly African-American (62.5%) and male (76.7%), met inclusion criteria. 20.1% reported that their first regular cannabis use (median age 15 years [range 8-48]) preceded their age at first psychotic symptoms (20 [4-50] years). Twenty (16.7%) participants met lifetime criteria for cannabis abuse; 98 (81.7%) met surrogate criteria for lifetime cannabis dependence. Withdrawal symptoms were reported by 113 (94.2%) participants, with 74.2% reporting ≥4 symptoms. The most frequently reported withdrawal symptoms were craving for cannabis (59.2%), feeling anxious (52.57%), feeling bored (47.5%), feeling sad or depressed (45.8%), feeling irritable or jumpy (45.0%), feeling restless (43.3%), and trouble failing asleep (33.3%). One hundred-and-four (92.0%) participants took some action to relieve at least one of their withdrawal symptoms during their index-quit attempt, including 26 (23.0%) participants who reported resuming cannabis use.

CONCLUSION

Cannabis withdrawal is a clinically significant feature of cannabis use among people with schizophrenia, may serve as a negative reinforcer for relapse, and deserves greater attention in treatment and research. Clinical Trials registration NCT00679016.

Test-retest reliability of self-report measures in a dually diagnosed sample

Many individuals diagnosed with a substance use disorder are also diagnosed with another psychiatric disorder. Little is known regarding which treatments are efficacious for these dually diagnosed individuals (DDI). Characterizing the psychometric properties of assessments used with DDI samples is essential to efficacy studies with DDI. This study examined the internal consistency and test-retest reliability of self-report instruments among DDI. Most subscales demonstrated high test-retest reliability; one subscale demonstrated poor reliability. Internal consistency was similar to that of non-DDI samples. This exploratory study suggests that, while some instruments should be interpreted cautiously, DDI samples can be accurately assessed with self-report measures.

The impact of alcohol and illicit drugs on people with psychosis: the second Australian National Survey of Psychosis

OBJECTIVE

To provide the most up-to-date prevalence estimates of alcohol and illicit drug use among individuals with psychosis in Australia, and explore correlates associated with a lifetime diagnosis of both alcohol abuse/dependence and cannabis abuse/dependence.

METHOD

This paper uses data from the Survey of High Impact Psychosis (SHIP), conducted as a follow-up to the first Australian National Low Prevalence (Psychotic) Disorders Study (1997-1998). The SHIP was a national study, carried out across five states, in which a sample of 1825 individuals was recruited through a two-phase sampling framework.

RESULTS

Alcohol and illicit drug use was highly prevalent for the entire sample. There were few significant differences in the prevalence or frequency of use across the diagnostic categories examined. Substantial increases in substance abuse/dependence were noted since the 1997-1998 survey (51% diagnosed with alcohol abuse/dependence, 51% with cannabis abuse/dependence and 32% with other illicit drug abuse/dependence, compared to 28%, 23% and 12% respectively, in the 1997-1998 survey by Kavanagh et al., 2004). Factors significantly associated with both lifetime alcohol and cannabis dependence included male gender, younger age, single marital status, lower educational attainment, shorter duration of illness, lifetime presence of hallucinations, higher negative syndrome score and lower body mass index (BMI). A number of other factors were found to be differentially associated with either lifetime alcohol or cannabis dependence.

CONCLUSIONS

The use of alcohol and illicit substances is common among people with a psychotic illness, with a concerning upward trend in rates of substance abuse/dependence since the 1997-1998 survey. Clinicians should be aware of the potential impact of concurrent substance use and provide integrated treatment for individuals presenting with psychotic illnesses. More research and investment in new intervention programs is required.

Does giving up substance use work for patients with psychosis? A systematic meta-analysis

OBJECTIVE

To assess the extent to which ceasing the use of cannabis or other substances reduces the symptoms and social disability associated with psychotic illness.

METHODS

The electronic databases CINAHL, EMBASE, MEDLINE and PsycINFO were searched for peer-reviewed publications in English that report data about the characteristics of current and former substance-using patients diagnosed with psychotic illnesses. The searches yielded 328 articles, of which 23 studies met the inclusion criteria. Four key outcome variables; positive symptoms, negative symptoms, ratings of depression and global function, and five other measures of outcome that were reported in five or more studies were examined using meta-analysis.

RESULTS

Current substance-using patients were significantly younger than former substance-using patients (standardised mean difference (SMD) = -0.38), but did not differ in age at onset of psychosis, sex, level of education or marital status. Current substance users had higher scores on rating scales of positive symptoms (SMD = 0.29) and depression (SMD = 0.36), and lower scores on global function (SMD = -0.26) when compared with former substance users. There was a significant improvement in the ratings of positive symptoms, mood and global function among patients who stopped using substances during the first episode of psychosis, while improvements in the symptoms of patients with a more established psychotic illness did not reach statistical significance.

CONCLUSION

The results suggest that substance use contributes to both the symptoms and the burden of disability experienced by patients with psychosis. Patients in the early stages of psychotic illness should be informed about the benefits of giving up substances earlier, rather than later in the illness. Psychiatric services should regard the treatment of substance use as an integral part of the treatment of psychotic disorders.

The impact of cannabis use on cognitive functioning in patients with schizophrenia: a meta-analysis of existing findings and new data in a first-episode sample

Cannabis use is highly prevalent among people with schizophrenia, and coupled with impaired cognition, is thought to heighten the risk of illness onset. However, while heavy cannabis use has been associated with cognitive deficits in long-term users, studies among patients with schizophrenia have been contradictory. This article consists of 2 studies. In Study I, a meta-analysis of 10 studies comprising 572 patients with established schizophrenia (with and without comorbid cannabis use) was conducted. Patients with a history of cannabis use were found to have superior neuropsychological functioning. This finding was largely driven by studies that included patients with a lifetime history of cannabis use rather than current or recent use. In Study II, we examined the neuropsychological performance of 85 patients with first-episode psychosis (FEP) and 43 healthy nonusing controls. Relative to controls, FEP patients with a history of cannabis use (FEP + CANN; n = 59) displayed only selective neuropsychological impairments while those without a history (FEP - CANN; n = 26) displayed generalized deficits. When directly compared, FEP + CANN patients performed better on tests of visual memory, working memory, and executive functioning. Patients with early onset cannabis use had less neuropsychological impairment than patients with later onset use. Together, these findings suggest that patients with schizophrenia or FEP with a history of cannabis use have superior neuropsychological functioning compared with nonusing patients. This association between better cognitive performance and cannabis use in schizophrenia may be driven by a subgroup of "neurocognitively less impaired" patients, who only developed psychosis after a relatively early initiation into cannabis use.

Evidence-based guidelines for the pharmacological treatment of schizophrenia: recommendations from the British Association for Psychopharmacology

These guidelines from the British Association for Psychopharmacology address the scope and targets of pharmacological treatment for schizophrenia. A consensus meeting, involving experts in schizophrenia and its treatment, reviewed key areas and considered the strength of evidence and clinical implications. The guidelines were drawn up after extensive feedback from the participants and interested parties, and cover the pharmacological management and treatment of schizophrenia across the various stages of the illness, including first-episode, relapse prevention, and illness that has proved refractory to standard treatment. The practice recommendations presented are based on the available evidence to date, and seek to clarify which interventions are of proven benefit. It is hoped that the recommendations will help to inform clinical decision making for practitioners, and perhaps also serve as a source of information for patients and carers. They are accompanied by a more detailed qualitative review of the available evidence. The strength of supporting evidence for each recommendation is rated.