Cannabis use and transition to psychosis in individuals at ultra-high risk: review and meta-analysis

Clinical and public safety risks associated with cannabis legalization and frequency of cannabis use among forensic mental health patients

BACKGROUND

There are ongoing concerns regarding the impact of Canada's cannabis legalization and commercialization on vulnerable persons such as those with serious forms of mental illness, including persons with schizophrenia-spectrum disorders and users of forensic mental health services. The primary objective of this study was to investigate the potential harms and mental health-related impacts associated with cannabis legalization on a sample of forensic patients in Ontario (N = 187).

METHODS

Using a pseudo-prospective design, we investigated the frequency of cannabis use over a four-year period encompassing two years preceding and two years following the legislative change. We recorded clinical and public safety outcomes (i.e., mental health deterioration, length of stay in the forensic system, rates of hospital readmission, victimization and violence) over the same period to test relationships between these variables and rates of cannabis use.

RESULTS

We found that one-third of patients either self-reported or were discovered, via urine testing, to have used cannabis over the study period. Frequency of use was lower in the pre-legalization period, and then gradually and significantly increased after legalization. Compared to patients with no cannabis use, those with one or more instances of use were more likely to be readmitted to hospital and had higher rated static risk factors for violence. However, there were no observed differences in the actual rate of violence between patients using and not using cannabis, nor differences in the rate of violence over time. Over half of the patients who used cannabis experienced a worsening of their mental health status in the week following use.

CONCLUSIONS

Cannabis use among those with SMI is associated with adverse clinical outcomes. Results from this study suggest that the mental health burdens associated with cannabis use have risen in terms of delayed clinical recovery and progress through the forensic system since legalization.

Enriching ultra-high risk for psychosis cohorts based on accumulated exposure to environmental risk factors for psychotic disorders

BACKGROUND AND HYPOTHESIS

Transition to psychosis rates within ultra-high risk (UHR) services have been declining. It may be possible to 'enrich' UHR cohorts based on the environmental characteristics seen more commonly in first-episode psychosis cohorts. This study aimed to determine whether transition rates varied according to the accumulated exposure to environmental risk factors at the individual (migrant status, asylum seeker/refugee status, indigenous population, cannabis/methamphetamine use), family (family history or parental separation), and neighborhood (population density, social deprivation, and fragmentation) level.

METHODS

The study included UHR people aged 15-24 who attended the PACE clinic from 2012 to 2016. Cox proportional hazards models (frequentist and Bayesian) were used to assess the association between individual and accumulated factors and transition to psychosis. UHR status and transition was determined using the CAARMS. Benjamini-Hochberg was used to correct for multiple comparisons in frequentist analyses.

RESULTS

Of the 461 young people included, 55.5% were female and median follow-up was 307 days (IQR: 188-557) and 17.6% (n = 81) transitioned to a psychotic disorder. The proportion who transitioned increased incrementally according to the number of individual-level risk factors present (HR = 1.51, 95% CIs 1.19-1.93, p < 0.001, pcorr = 0.01). The number of family- and neighborhood-level exposures did not increase transition risk (p > 0.05). Cannabis use was the only specific risk factor significantly associated with transition (HR = 1.89, 95% CIs 1.22-2.93, pcorr = 0.03, BF = 6.74).

CONCLUSIONS

There is a dose-response relationship between exposure to individual-level psychosis-related environmental risk factors and transition risk in UHR patients. If replicated, this could be incorporated into a novel approach to identifying the highest-risk individuals within clinical services.

The Complex Latent Structure of Attenuated Psychotic Symptoms: Hierarchical and Bifactor Models of SIPS Symptoms Replicated in Two Large Samples at Clinical High Risk for Psychosis

BACKGROUND AND HYPOTHESIS

The Structured Interview for Psychosis-Risk Syndromes (SIPS) and other assessments of psychosis risk define clinical high risk for psychosis (CHR) by the presence of attenuated psychotic symptoms. Despite extensive research on attenuated psychotic symptoms, substantial questions remain about their internal psychometric structure and relationships to comorbid non-psychotic symptoms.

STUDY DESIGN

Hierarchical and bifactor models were developed for the SIPS in a large CHR sample (NAPLS-3, N = 787) and confirmed through preregistered replication in an independent sample (NAPLS-2, N = 1043). Criterion validity was tested through relationships with CHR status, comorbid symptoms/diagnoses, functional impairment, demographics, neurocognition, and conversion to psychotic disorders.

STUDY RESULTS

Most variance in SIPS items (75%-77%) was attributable to a general factor. Hierarchical and bifactor models included a general factor and five specific/lower-order factors (positive symptoms, eccentricity, avolition, lack of emotion, and deteriorated thought process). CHR participants were elevated on the general factor and the positive symptoms factor. The general factor was associated with depressive symptoms; functional impairment; and mood, anxiety, and schizotypal personality diagnoses. The general factor was the best predictor of psychotic disorders (d ≥ 0.50). Positive symptoms and eccentricity had specific effects on conversion outcomes. The deteriorated thought process was least meaningful/replicable.

CONCLUSIONS

Attenuated psychotic symptoms, measured by the SIPS, have a complex hierarchical structure with a strong general factor. The general factor relates to internalizing symptoms and functional impairment, emphasizing the roles of general psychopathological distress/impairment in psychosis risk. Shared symptom variance complicates the interpretation of raw symptom scores. Broad transdiagnostic assessment is warranted to model psychosis risk accurately.

Psychosis Spectrum Symptoms Before and After Adolescent Cannabis Use Initiation

Importance

Adolescent cannabis use has been consistently posited to contribute to the onset and progression of psychosis. However, alternative causal models may account for observed associations between cannabis use and psychosis risk, including shared vulnerability for both cannabis use and psychosis or efforts to self-medicate distress from psychosis spectrum symptomology.

Objective

To test 3 hypotheses that may explain cannabis-psychosis risk associations by modeling psychosis spectrum symptom trajectories prior to and after cannabis initiation across adolescent development (approximately 10-15 years of age).

Design, Setting, and Participants

This cohort study used data from 5 waves across 4 years of follow-up from the Adolescent Brain Cognitive Development (ABCD) Study. The ABCD study is an ongoing large-scale, longitudinal study of brain development and mental and physical health of children in the US launched in June 2016. Data are collected from 21 research sites. The study included data from 11 868 adolescents aged 9 to 10 years at baseline. Three participants were excluded from the present analysis owing to missing data. Data analysis was performed from September 2023 to July 2024.

Main Outcomes and Measures

Discontinuous growth curve modeling was used to assess trajectories of psychosis spectrum symptoms before and after cannabis initiation. Control variables considered for this investigation were age, sex, internalizing and externalizing symptoms, socioeconomic status, parental mental health, and other substance use.

Results

Among the 11 858 participants at wave 1, the mean (SD) age was 9.5 (0.5) years; 6182 (52%) participants were male. Consistent with a shared vulnerability hypothesis, adolescents who used cannabis at any point during the study period reported a greater number of psychosis spectrum symptoms (B, 0.86; 95% CI, 0.68-1.04) and more distress (B, 1.17; 95% CI, 0.96-1.39) from psychosis spectrum symptoms relative to those who never used cannabis. Additionally, consistent with a self-medication hypothesis, the number of psychosis spectrum symptoms (B, 0.16; 95% CI, 0.12-0.20) and distress (B, 0.23; 95% CI, 0.21-0.26) from psychosis spectrum symptoms increased in the time leading up to cannabis initiation. We observed mixed evidence for an increase in psychosis symptoms after cannabis initiation (ie, contributing risk hypothesis).

Conclusion and Relevance

The findings underscore the importance of accounting for shared vulnerability and self-medication effects when modeling cannabis-psychosis risk associations.

Occasional cannabis use is associated with higher premorbid functioning and IQ in youth at clinical high-risk (CHR) for psychosis: Parallel findings to psychosis cohorts

BACKGROUND

Neurocognitive deficits have been widely reported in clinical high-risk for psychosis (CHR) populations. Additionally, rates of cannabis use are high among CHR youth and are associated with greater symptom severity. Cannabis use has been sometimes shown to be associated with better neurocognition in more progressed psychosis cohorts, therefore in this study we aimed to determine whether a similar pattern was present in CHR.

METHODS

CHR participants ages 12-30 from the North American Prodromal Longitudinal Study (NAPLS-3) (N = 698) were grouped according to: "minimal to no cannabis use" (n = 406), "occasional use" (n = 127), or "frequent use" (n = 165). At baseline, cannabis use groups were compared on neurocognitive tests, clinical, and functional measures. Follow-up analyses were used to model relationships between cannabis use frequency, neurocognition, premorbid, and social functioning.

RESULTS

Occasional cannabis users performed significantly better than other use-groups on measures of IQ, with similar trend-level patterns observed across neurocognitive domains. Occasional cannabis users demonstrated better social, global, and premorbid functioning compared to the other use-groups and less severe symptoms compared to the frequent use group. Follow-up structural equation modeling/path analyses found significant positive associations between premorbid functioning, social functioning, and IQ, which in turn was associated with occasional cannabis use frequency.

DISCUSSION

Better premorbid functioning positively predicts both better social functioning and higher IQ which in turn is associated with a moderate cannabis use pattern in CHR, similar to reports in first-episode and chronic psychosis samples. Better premorbid functioning likely represents a protective factor in the CHR population and predicts a better functional outcome.

Longitudinal associations between psychedelic use and psychotic symptoms in the United States and the United Kingdom

It has long been speculated that psychedelic use could provoke the onset of psychosis, but there is little evidence to support this conjecture. Using a longitudinal research design with samples representative of the US and UK adult populations with regard to sex, age, and ethnicity (n = 9732), we investigated associations between psychedelic use and change in the number of psychotic symptoms during the two-month study period. In covariate-adjusted regression models, psychedelic use during the study period was not associated with a change in the number of psychotic symptoms unless it interacted with a personal or family history of bipolar disorder, in which case the number of symptoms increased, or with a personal (but not family) history of psychotic disorders, in which case the number of symptoms decreased. Taken together, these findings indicate that psychedelic use may affect psychotic symptoms in individuals with a personal or family history of certain disorders characterized by psychotic symptomatology.

Fronto-temporal cortical grey matter thickness and surface area in the at-risk mental state and recent-onset schizophrenia: a magnetic resonance imaging study

BACKGROUND

Studies to date examining cortical thickness and surface area in young individuals At Risk Mental State (ARMS) of developing psychosis have revealed inconsistent findings, either reporting increased, decreased or no differences compared to mentally healthy individuals. The inconsistencies may be attributed to small sample sizes, varying age ranges, different ARMS identification criteria, lack of control for recreational substance use and antipsychotic pharmacotherapy, as well as different methods for deriving morphological brain measures.

METHODS

A surfaced-based approach was employed to calculate fronto-temporal cortical grey matter thickness and surface area derived from magnetic resonance imaging (MRI) data collected from 44 young antipsychotic-naïve ARMS individuals, 19 young people with recent onset schizophrenia, and 36 age-matched healthy volunteers. We conducted group comparisons of the morphological measures and explored their association with symptom severity, global and socio-occupational function levels, and the degree of alcohol and cannabis use in the ARMS group.

RESULTS

Grey matter thickness and surface areas in ARMS individuals did not significantly differ from their age-matched healthy counterparts. However, reduced left-frontal grey matter thickness was correlated with greater symptom severity and lower function levels; the latter being also correlated with smaller left-frontal surface areas. ARMS individuals with more severe symptoms showed greater similarities to the recent onset schizophrenia group. The morphological measures in ARMS did not correlate with the lifetime level of alcohol or cannabis use.

CONCLUSIONS

Our findings suggest that a decline in function levels and worsening mental state are associated with morphological changes in the left frontal cortex in ARMS but to a lesser extent than those seen in recent onset schizophrenia. Alcohol and cannabis use did not confound these findings. However, the cross-sectional nature of our study limits our ability to draw conclusions about the potential progressive nature of these morphological changes in ARMS.

Unhealthy behaviors associated with mental health disorders: a systematic comparative review of diet quality, sedentary behavior, and cannabis and tobacco use

Background

There are well-established literatures documenting the associations between mental disorders and unhealthy behaviors such as poor diet quality, sedentary behavior, and cannabis and tobacco use. Few studies have attempted to understand the respective findings in light of each other, however.

Objective

The purpose of this review was to assemble comparable data for each behavior-disorder association and assess the associations in terms of their overall strength. The review aimed to include a representative, but not exhaustive, range of studies that would allow for explorative comparisons.

Methods

Eligible studies were identified via Pubmed searches and citation searching, restricted to publications no older than 2015 written in English. To obtain comparable data, only studies that reported findings as odds ratios were included, and risk of bias related to study samples, behavioral measurement disparities, and control variables was assessed via sensitivity analyses. Findings for each disorder were compared on the basis of different measures of central tendency.

Results

From 3,682 records, 294 studies were included. The review found evidence of associations between each of the four unhealthy behaviors and psychosis, depression, anxiety, bipolar disorder, attention-deficit/hyperactivity disorder (ADHD), and post-traumatic stress disorder (PTSD), while personality disorder was only investigated in relation to cannabis and tobacco use. In overall comparison, the associations were generally of similar strength, and only the association between cannabis use and personality disorder was exceptional in terms of being significantly stronger than its counterparts across disorders and across behaviors. Analyses of bias risk identified some influence from behavioral measurement disparities and lack of adequate statistical control, but findings were generally robust across a range of sensitivity analyses.

Conclusion

This explorative and comparative review found that poor diet quality, sedentary behavior, and cannabis and tobacco use are about equally strongly associated with a range of different mental disorders. Given the general nature of these associations, we should probably understand them to reflect a general and shared etiology. However, the findings in this review should be regarded as tentative until confirmed by more comprehensive investigations.

Modelling the effects of the exposome score within the extended psychosis phenotype

It has been reported that cumulative measures of risk factors for psychosis might help to predict its development. However, it remains unknown as to whether these measures are also associated with the extended psychosis phenotype that refers to a continuum of features bridging subclinical symptoms with clinically relevant outcomes. In this study, we aimed to investigate the association of the exposome score (ES) with psychosis risk in a non-clinical population. A total of 1100 non-clinical adults (aged 18-35 years, 51.4% females) with a negative history of psychiatric treatment were recruited. The Prodromal Questionnaire-16 (PQ-16) was used to screen for psychosis risk. Self-reports were used to record environmental exposures. The ES was significantly higher in participants with the positive PQ-16 screening. Specifically, the prevalence of obstetric complications, non-right handedness, all categories of childhood trauma, and problematic cannabis use was significantly higher in this group of participants. A network analysis demonstrated that the ES was directly connected not only to items representing psychotic experiences ("paranoid thoughts", "a lack of control over own ideas or thoughts", "thought echo", and "being distracted by distant sounds") but also those covering depressive or anxiety symptoms ("uninterested in things used to enjoy" and "feeling anxious when meeting people for the first time"). In conclusion, the ES is associated with the extended psychosis phenotype, suggesting its potential to identify individuals who may benefit from further psychosis risk assessment. The ES appears to contribute to non-specific psychopathology, which may, in some cases, progress to psychosis.

Cannabis use influences disorganized symptoms severity but not transition in a cohort of non-help-seeking individuals at-risk for psychosis from São Paulo, Brazil

BACKGROUND

Cannabis use is associated with an increased risk of developing a psychotic disorder. However, in individuals with at-risk mental states for psychosis (ARMS) this association is not clear, as well as the impact of cannabis use on symptom severity. The objective of this study was to evaluate the association of cannabis use patterns and ARMS risk status, transition to psychotic and psychiatric disorders, and psychopathology.

METHOD

A sample of 109 ARMS and 197 control individuals was drawn from the general population. Lifetime, maximum and current amount of cannabis use were assessed with the South Westminster modified questionnaire. Participants were followed-up for a mean of 2.5 years and reassessed for transition to any psychiatric disorder.

RESULTS

There were no differences between ARMS and controls regarding lifetime use, current amount of use, or maximum amount of cannabis use. There were also no differences between those who transitioned to a psychiatric disorder and those who did not regarding cannabis use variables. In ARMS individuals, cannabis use was significantly related to disorganization symptoms.

CONCLUSION

The results of this study suggest that cannabis plays a role in the psychopathology of ARMS individuals, leading to more severe symptomatology.

Assessing evidence supporting cannabis harm reduction practices for adolescents at clinical high-risk for psychosis: a review and clinical implementation tool

Cannabis use is consistently associated with both increased incidence of frank psychotic disorders and acute exacerbations of psychotic symptoms in healthy individuals and people with psychosis spectrum disorders. Although there is uncertainty around causality, cannabis use may be one of a few modifiable risk factors for conversion to psychotic disorders in individuals with Clinical High Risk for Psychosis (CHR-P) syndromes, characterized by functionally impairing and distressing subthreshold psychotic symptoms. To date, few recommendations beyond abstinence to reduce adverse psychiatric events associated with cannabis use have been made. This narrative review synthesizes existing scientific literature on cannabis' acute psychotomimetic effects and epidemiological associations with psychotic disorders in both CHR-P and healthy individuals to bridge the gap between scientific knowledge and practical mental health intervention. There is compelling evidence for cannabis acutely exacerbating psychotic symptoms in CHR-P, but its impact on conversion to psychotic disorder is unclear. Current evidence supports a harm reduction approach in reducing frequency of acute psychotic-like experiences, though whether such interventions decrease CHR-P individuals' risk of conversion to psychotic disorder remains unknown. Specific recommendations include reducing frequency of use, lowering delta-9-tetrahydrocannabinol content in favor of cannabidiol-only products, avoiding products with inconsistent potency like edibles, enhancing patient-provider communication about cannabis use and psychotic-like experiences, and utilizing a collaborative and individualized therapeutic approach. Despite uncertainty surrounding cannabis' causal association with psychotic disorders, cautious attempts to reduce acute psychosis risk may benefit CHR-P individuals uninterested in abstinence. Further research is needed to clarify practices associated with minimization of cannabis-related psychosis risk.

Using Task-fMRI to Explore the Relationship Between Lifetime Cannabis Use and Cognitive Control in Individuals With First-Episode Schizophrenia

While continued cannabis use and misuse in individuals with schizophrenia is associated with a variety of negative outcomes, individuals with a history of use tend to show higher cognitive performance compared to non-users. While this is replicated in the literature, few studies have used task-based functional magnetic resonance imaging (fMRI) to evaluate whether the brain networks underpinning these cognitive features are similarly impacted. Forty-eight first-episode individuals with schizophrenia (FES) with a history of cannabis use (FES + CAN), 28 FES individuals with no history of cannabis use (FES-CAN), and 59 controls (CON) performed the AX-Continuous Performance Task during fMRI. FES+CAN showed higher cognitive control performance (d'-context) compared to FES-CAN (P < .05, ηp 2 = 0.053), and both FES+CAN (P < .05, ηp 2 = 0.049) and FES-CAN (P < .001, ηp 2 = 0.216) showed lower performance compared to CON. FES+CAN (P < .05, ηp 2 = 0.055) and CON (P < 0.05, ηp 2 = 0.058) showed higher dorsolateral prefrontal cortex (DLPFC) activation during the task compared to FES-CAN, while FES+CAN and CON were not significantly different. Within the FES+CAN group, the younger age of initiation of cannabis use was associated with lower IQ and lower global functioning. More frequent use was also associated with higher reality distortion symptoms at the time of the scan. These data are consistent with previous literature suggesting that individuals with schizophrenia and a history of cannabis use have higher cognitive control performance. For the first time, we also reveal that FES+CAN have higher DLPFC brain activity during cognitive control compared to FES-CAN. Several possible explanations for these findings are discussed.

Influence of cannabis use on incidence of psychosis in people at clinical high risk

AIMS

Evidence for case-control studies suggests that cannabis use is a risk factor for the development of psychosis. However, there have been limited prospective studies and the direction of this association remains controversial. The primary aim of the present study was to examine the association between cannabis use and the incidence of psychotic disorders in people at clinical high risk of psychosis. Secondary aims were to assess associations between cannabis use and the persistence of psychotic symptoms, and with functional outcome.

METHODS

Current and previous cannabis use were assessed in individuals at clinical high risk of psychosis (n = 334) and healthy controls (n = 67), using a modified version of the Cannabis Experience Questionnaire. Participants were assessed at baseline and followed up for 2 years. Transition to psychosis and persistence of psychotic symptoms were assessed using the Comprehensive Assessment of At-Risk Mental States criteria. Level of functioning at follow up was assessed using the Global Assessment of Functioning disability scale.

RESULTS

During follow up, 16.2% of the clinical high-risk sample developed psychosis. Of those who did not become psychotic, 51.4% had persistent symptoms and 48.6% were in remission. There was no significant association between any measure of cannabis use at baseline and either transition to psychosis, the persistence of symptoms, or functional outcome.

CONCLUSIONS

These findings contrast with epidemiological data that suggest that cannabis use increases the risk of psychotic disorder.

Balancing risks and benefits of cannabis use: umbrella review of meta-analyses of randomised controlled trials and observational studies

OBJECTIVE

To systematically assess credibility and certainty of associations between cannabis, cannabinoids, and cannabis based medicines and human health, from observational studies and randomised controlled trials (RCTs).

DESIGN

Umbrella review.

DATA SOURCES

PubMed, PsychInfo, Embase, up to 9 February 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Systematic reviews with meta-analyses of observational studies and RCTs that have reported on the efficacy and safety of cannabis, cannabinoids, or cannabis based medicines were included. Credibility was graded according to convincing, highly suggestive, suggestive, weak, or not significant (observational evidence), and by GRADE (Grading of Recommendations, Assessment, Development and Evaluations) (RCTs). Quality was assessed with AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). Sensitivity analyses were conducted.

RESULTS

101 meta-analyses were included (observational=50, RCTs=51) (AMSTAR 2 high 33, moderate 31, low 32, or critically low 5). From RCTs supported by high to moderate certainty, cannabis based medicines increased adverse events related to the central nervous system (equivalent odds ratio 2.84 (95% confidence interval 2.16 to 3.73)), psychological effects (3.07 (1.79 to 5.26)), and vision (3.00 (1.79 to 5.03)) in people with mixed conditions (GRADE=high), improved nausea/vomit, pain, spasticity, but increased psychiatric, gastrointestinal adverse events, and somnolence among others (GRADE=moderate). Cannabidiol improved 50% reduction of seizures (0.59 (0.38 to 0.92)) and seizure events (0.59 (0.36 to 0.96)) (GRADE=high), but increased pneumonia, gastrointestinal adverse events, and somnolence (GRADE=moderate). For chronic pain, cannabis based medicines or cannabinoids reduced pain by 30% (0.59 (0.37 to 0.93), GRADE=high), across different conditions (n=7), but increased psychological distress. For epilepsy, cannabidiol increased risk of diarrhoea (2.25 (1.33 to 3.81)), had no effect on sleep disruption (GRADE=high), reduced seizures across different populations and measures (n=7), improved global impression (n=2), quality of life, and increased risk of somnolence (GRADE=moderate). In the general population, cannabis worsened positive psychotic symptoms (5.21 (3.36 to 8.01)) and total psychiatric symptoms (7.49 (5.31 to 10.42)) (GRADE=high), negative psychotic symptoms, and cognition (n=11) (GRADE=moderate). In healthy people, cannabinoids improved pain threshold (0.74 (0.59 to 0.91)), unpleasantness (0.60 (0.41 to 0.88)) (GRADE=high). For inflammatory bowel disease, cannabinoids improved quality of life (0.34 (0.22 to 0.53) (GRADE=high). For multiple sclerosis, cannabinoids improved spasticity, pain, but increased risk of dizziness, dry mouth, nausea, somnolence (GRADE=moderate). For cancer, cannabinoids improved sleep disruption, but had gastrointestinal adverse events (n=2) (GRADE=moderate). Cannabis based medicines, cannabis, and cannabinoids resulted in poor tolerability across various conditions (GRADE=moderate). Evidence was convincing from observational studies (main and sensitivity analyses) in pregnant women, small for gestational age (1.61 (1.41 to 1.83)), low birth weight (1.43 (1.27 to 1.62)); in drivers, car crash (1.27 (1.21 to 1.34)); and in the general population, psychosis (1.71 (1.47 to 2.00)). Harmful effects were noted for additional neonatal outcomes, outcomes related to car crash, outcomes in the general population including psychotic symptoms, suicide attempt, depression, and mania, and impaired cognition in healthy cannabis users (all suggestive to highly suggestive).

CONCLUSIONS

Convincing or converging evidence supports avoidance of cannabis during adolescence and early adulthood, in people prone to or with mental health disorders, in pregnancy and before and while driving. Cannabidiol is effective in people with epilepsy. Cannabis based medicines are effective in people with multiple sclerosis, chronic pain, inflammatory bowel disease, and in palliative medicine but not without adverse events.

STUDY REGISTRATION

PROSPERO CRD42018093045.

FUNDING

None.

Predictors of transition in patients with clinical high risk for psychosis: an umbrella review

Diagnosis of a clinical high-risk (CHR) state enables timely treatment of individuals at risk for a psychotic disorder, thereby contributing to improving illness outcomes. However, only a minority of patients diagnosed with CHR will make the transition to overt psychosis. To identify patients most likely to benefit from early intervention, several studies have investigated characteristics that distinguish CHR patients who will later develop a psychotic disorder from those who will not. We aimed to summarize evidence from systematic reviews and meta-analyses on predictors of transition to psychosis in CHR patients, among characteristics and biomarkers assessed at baseline. A systematic search was conducted in Pubmed, Scopus, PsychInfo and Cochrane databases to identify reviews and meta-analyses of studies that investigated specific baseline predictors or biomarkers for transition to psychosis in CHR patients using a cross-sectional or longitudinal design. Non-peer-reviewed publications, gray literature, narrative reviews and publications not written in English were excluded from analyses. We provide a narrative synthesis of results from all included reviews and meta-analyses. For each included publication, we indicate the number of studies cited in each domain and its quality rating. A total of 40 publications (21 systematic reviews and 19 meta-analyses) that reviewed a total of 272 original studies qualified for inclusion. Baseline predictors most consistently associated with later transition included clinical characteristics such as attenuated psychotic and negative symptoms and functioning, verbal memory deficits and the electrophysiological marker of mismatch negativity. Few predictors reached a level of evidence sufficient to inform clinical practice, reflecting generalizability issues in a field characterized by studies with small, heterogeneous samples and relatively few transition events. Sample pooling and harmonization of methods across sites and projects are necessary to overcome these limitations.

Risk-thresholds for the association between frequency of cannabis use and the development of psychosis: a systematic review and meta-analysis

BACKGROUND

Epidemiological studies show a dose-response association between cannabis use and the risk of psychosis. This review aimed to determine whether there are identifiable risk-thresholds between the frequency of cannabis use and psychosis development.

METHODS

Systematic search of Embase, MEDLINE, PsycINFO, CINAHL, and Web of Science for relevant studies (1 January 2010-26 April 2021). Case-control or cohort studies that investigated the relationship between cannabis use and the risk of psychosis development that reported effect estimates [odds ratios (OR), hazard ratios (HR), risk ratios (RR)] or the raw data to calculate them, with information on the frequency of cannabis consumption were included. Effect estimates were extracted from individual studies and converted to RR. Two-stage dose-response multivariable meta-analytic models were utilized and sensitivity analyses conducted. The Newcastle Ottawa Scale was used to assess the risk of bias of included studies.

RESULTS

Ten original (three cohorts, seven case-control) studies were included, including 7390 participants with an age range of 12-65 years. Random-effect model meta-analyses showed a significant log-linear dose-response association between cannabis use frequency and psychosis development. A restricted cubic-splines model provided the best fit for the data, with the risk of psychosis significantly increasing for weekly or more frequent cannabis use [RR = 1.01, 95% confidence interval (CI) 0.93-1.11 yearly; RR = 1.10, 95% CI 0.97-1.25 monthly; RR = 1.35, 95% CI 1.19-1.52 weekly; RR = 1.76, 95% CI 1.47-2.12 daily].

CONCLUSION

Individuals using cannabis frequently are at increased risk of psychosis, with no significant risk associated with less frequent use. Public health prevention messages should convey these risk-thresholds, which should be refined through further work.

Schizotypal traits in a large sample of high-school and university students from Tunisia: correlates and measurement invariance of the arabic schizotypal personality questionnaire across age and sex

BACKGROUND

The main goal of the present study was to examine the characteristics of schizotypal traits and their correlations with genetic (i.e., family history of mental illness), demographic (i.e., age, sex), environmental (e.g., income, urbanicity, tobacco/alcohol/cannabis use), and psychological (i.e., personal history of mental illness other than psychosis) factors in Tunisian high-school and university students. Our secondary goal was to contribute the literature by examining the factor structure and factorial invariance of the Arabic Schizotypal Personality Questionnaire (SPQ) across sex and age (adolescents [12-18 years] vs. young adults [18-35 years]) groups.

METHOD

This was a cross-sectional study involving 3166 students: 1160 (36.6%) high-school students (53.0% females, aged 14.9 ± 1.8); and 2006 (63.4%) university students (63.9% females, aged 21.8 ± 2.3). All students were asked to complete a paper-and-pencil self-administered questionnaire containing sociodemographic characteristics as well as the Arabic version of the SPQ.

RESULTS

The total sample yielded total SPQ scores of 24.1 ± 16.6 out of 74. The SPQ yielded good composite reliability as attested by McDonald's omega values ranging from .68 to .80 for all nine subscales. Confirmatory Factor Analysis indicated that fit of the 9-factor model of SPQ scores was acceptable. This model is invariant (at the configural, metric and structural levels) across sex and age. Except for "Odd or eccentric behavior", all schizotypy features were significantly higher among female students compared to males. Multivariable analyses showed that female sex, being a university student, lowest family incomes, tobacco use, and having a personal history of psychiatric illness were significantly associated with higher positive, negative and disorganized schizotypy subscales scores.

CONCLUSION

Future research still needs to confirm our findings and investigate the contribution of the identified factors in the development of clinical psychosis. We can also conclude that the Arabic SPQ is appropriate for measuring and comparing schizotypy across age and sex in clinical and research settings. These findings are highly relevant and essential for ensuring the clinical utility and applicability of the SPQ in cross-cultural research.

Recommendations for Reducing the Risk of Cannabis Use-Related Adverse Psychosis Outcomes: A Public Mental Health-Oriented Evidence Review

Objective: Cannabis use is increasingly normalized; psychosis is a major adverse health outcome. We reviewed evidence on cannabis use-related risk factors for psychosis outcomes at different stages toward recommendations for risk reduction by individuals involved in cannabis use. Methods: We searched primary databases for pertinent literature/data 2016 onward, principally relying on reviews and high-quality studies which were narratively summarized and quality-graded; recommendations were developed by international expert consensus. Results: Genetic risks, and mental health/substance use problem histories elevate the risks for cannabis-related psychosis. Early age-of-use-onset, frequency-of-use, product composition (i.e., THC potency), use mode and other substance co-use all influence psychosis risks; the protective effects of CBD are uncertain. Continuous cannabis use may adversely affect psychosis-related treatment and medication effects. Risk factor combinations further amplify the odds of adverse psychosis outcomes. Conclusions: Reductions in the identified cannabis-related risks factors-short of abstinence-may decrease risks of related adverse psychosis outcomes, and thereby protect cannabis users' health.

The 3-year progression of clinically significant psychotic-like experiences in a general adult population in Lagos, Nigeria

PURPOSE

The study assessed the 3-year progression of clinically significant psychotic-like experience (CS-PLE) symptoms in an adult general population in terms of stability or remission of symptoms and transition to psychosis.

METHODS

Participants (n = 1292) aged 18-65 years with CS-PLE were assessed at baseline for sociodemographic details, family history of mental illness, functioning status, common mental disorders, alcohol, and substance use disorders. Three years later they were reassessed for diagnosis of psychosis, presence or remission of PLE symptoms, and contact with mental health services.

RESULTS

The mean age of the participants at baseline in years was 36.56 (SD = 11.66) and there were 855 (66.2%) females. By the 3rd year follow-up, 95 (7.3%) had transited to psychosis, while 850 (65.5%) had persistent CS-PLE symptoms and the rest 347 (27.2%) were in remission. Only history of mental illness in the immediate family (HR 4.81, 95% CI 1.40-16.47, P = 0.013) and regular use of cannabis at less than 18 years of age (HR 0.65, 95% CI 0.55-0.77, P < 0.001) were the independent predictors of conversion to psychosis at 3 years.

CONCLUSION

The rate of TTP in the non-clinical population with elevated risk may be lower than that earlier reported in the western literature. Interventions aimed at preventing transition to psychosis in high risk groups must pay attention to early onset users of cannabis and those with family history of mental illness.

Substance use and psychotic-like experiences in young people: a systematic review and meta-analysis

This study aimed to systematically review and synthesise the available evidence on the prevalence and associations between psychotic-like experiences (PLEs) and substance use in children and adolescents aged ⩽17 years, prior to the typical age of development of prodromal symptoms of psychosis. As substance use has been associated with earlier age of psychosis onset and more severe illness, identifying risk processes in the premorbid phase of the illness may offer opportunities to prevent the development of prodromal symptoms and psychotic illness. MEDLINE, PsycINFO, and CINAHL databases were searched for chart review, case-control, cohort, twin, and cross-sectional studies. Study reporting was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist, and pooled evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Searches identified 55 studies that met inclusion criteria. Around two-in-five substance users reported PLEs [rate = 0.41, 95% confidence interval (CI) 0.32-0.51; low quality evidence], and one-in-five with PLEs reported using substances (rate = 0.19, 95% CI 0.12-0.28; moderate-to-high quality evidence). Substance users were nearly twice as likely to report PLEs than non-users [odds ratio (OR) 1.77, 95% CI 1.55-2.02; moderate quality evidence], and those with PLEs were twice as likely to use substances than those not reporting PLEs (OR 1.93, 95% CI 1.55-2.41; very low quality evidence). Younger age was associated with greater odds of PLEs in substance users compared to non-users. Young substance users may represent a subclinical at-risk group for psychosis. Developing early detection and intervention for both substance use and PLEs may reduce long-term adverse outcomes.

Hippocampal Glutamate, Resting Perfusion and the Effects of Cannabidiol in Psychosis Risk

Background

Preclinical and human data suggest that psychosis onset involves hippocampal glutamatergic dysfunction, driving hyperactivity and hyperperfusion in a hippocampal-midbrain-striatal circuit. Whether glutamatergic dysfunction is related to cerebral perfusion in patients at clinical high risk (CHR) for psychosis, and whether cannabidiol (CBD) has ameliorative effects on glutamate or its relationship with perfusion remains unknown.

Methods

Using a double-blind, parallel-group design, 33 CHR patients were randomized to a single 600 mg dose of CBD or placebo; 19 healthy controls did not receive any drug. Proton magnetic resonance spectroscopy was used to measure glutamate concentrations in left hippocampus. We examined differences relating to CHR status (controls vs placebo), effects of CBD (placebo vs CBD), and linear between-group effects, such that placebo>CBD>controls or controls>CBD>placebo. We also examined group × glutamate × cerebral perfusion (measured using Arterial Spin Labeling) interactions.

Results

Compared to controls, CHR-placebo patients had significantly lower hippocampal glutamate (P =.015) and a significant linear relationship was observed across groups, such that glutamate was highest in controls, lowest in CHR-placebo, and intermediate in CHR-CBD (P =.031). Moreover, there was a significant interaction between group (controls vs CHR-placebo), hippocampal glutamate, and perfusion in the putamen and insula (P FWE =.012), with a strong positive correlation in CHR-placebo vs a negative correlation in controls.

Conclusions

Our findings suggest that hippocampal glutamate is lower in CHR patients and may be partially normalized by a single dose of CBD. Furthermore, we provide the first in vivo evidence of an abnormal relationship between hippocampal glutamate and perfusion in the striatum and insula in CHR.

Consensus paper of the WFSBP task force on cannabis, cannabinoids and psychosis

OBJECTIVES

The liberalisation of cannabis laws, the increasing availability and potency of cannabis has renewed concern about the risk of psychosis with cannabis.

METHODS

The objective of the WFSBP task force was to review the literature about this relationship.

RESULTS

Converging lines of evidence suggest that exposure to cannabis increases the risk for psychoses ranging from transient psychotic states to chronic recurrent psychosis. The greater the dose, and the earlier the age of exposure, the greater the risk. For some psychosis outcomes, the evidence supports some of the criteria of causality. However, alternate explanations including reverse causality and confounders cannot be conclusively excluded. Furthermore, cannabis is neither necessary nor sufficient to cause psychosis. More likely it is one of the multiple causal components. In those with established psychosis, cannabis has a negative impact on the course and expression of the illness. Emerging evidence also suggests alterations in the endocannabinoid system in psychotic disorders.

CONCLUSIONS

Given that exposure to cannabis and cannabinoids is modifiable, delaying or eliminating exposure to cannabis or cannabinoids, could potentially impact the rates of psychosis related to cannabis, especially in those who are at high risk for developing the disorder.

Cannabis use and attenuated positive and negative symptoms in youth at clinical high risk for psychosis

Cannabis use is more prevalent among youth at clinical high-risk (CHR) for psychosis than healthy controls (HC). There is mixed evidence as to whether cannabis use is associated with increased severity of attenuated psychotic symptoms (APS) or whether current cannabis use is associated with the transition to psychosis. This study aims to assess cannabis use differences between CHR youth and HC and the impact of cannabis use on APS, clinical status, and transition to psychosis. Participants were from the North American Prodrome Longitudinal Study-3, a prospective longitudinal study including 710 individuals, age 12-30, meeting criteria for a psychosis risk syndrome based on the Structured Interview for Psychosis-Risk Syndromes, and 96 HC. Cannabis use, frequency, and severity of use were assessed with the Alcohol Use Scale/Drug Use Scale. Current and past cannabis use disorders were assessed with the Structured Clinical Interview for DSM-5. Compared to HC, CHR individuals reported significantly increased lifetime cannabis use, during the past six months, and at baseline; greater frequency and severity of cannabis use; and increased prevalence of cannabis use disorder. Relative to CHR youth without cannabis use, CHR cannabis users had significantly higher ratings on baseline grandiosity and lower 12-months social anhedonia. Severity of cannabis was unrelated to clinical status at 2-years, and it did not differentiate CHR individuals who transitioned to psychosis from those who did not. However, a major limitation was that the current number of CHR cannabis users was small, and survival analyses resulted in a smaller power than the 80 % recommended.

Association between cannabis use and suicidal behavior: A systematic review of cohort studies

The use of cannabis is highly prevalent worldwide, with known short and long-term adverse effects. However, the relationship between cannabis use and suicidal behavior remains relatively unexplored and this paper aims to unify existing literature on the topic. A systematic review was conducted using MEDLINE, Embase, PsycINFO and LILACS databases with a supplementary search to identify cohort articles published up to January 2020, with no age delimitation for the samples. This review aimed to address the relationship between cannabis use and suicidal behavior, defined as suicidal ideation, attempted suicide or completed suicide. Twenty-two articles were identified, with no clear consensus, irrespective of the outcome being investigated. This was the case even when taking into consideration only those studies with a sound methodology (according to the Newcastle-Ottawa scale). Studies that identified an association explored the importance of the endocannabinoid system as well as the psychosocial context of the individual while developing suicidal behavior, with certain studies demonstrating that greater intensity or precocity of cannabis use increases the strength of this association. The relationship between cannabis use and suicidal behavior is complex, with no consensus in the literature. Further studies with standardized definitions for cannabis use, including frequency of use, along with improved controls for confounding variables are needed.

No rest for the weary: Prevalence, impact and nature of sleep problems among young people at risk of psychosis

AIMS

Sleep problems are common in people with a psychosis-spectrum diagnosis and are associated with worse psychotic symptoms and lower quality of life. Sleep problems are also frequent in individuals at a clinical high risk for psychosis (CHR-P) however, less is known about the prevalence and association with symptoms in this population. This study investigates the prevalence of sleep problems within CHR-P individuals and the associations with attenuated positive symptoms, transition to psychosis, time to transition to psychosis and functioning.

METHODS

The clinical records interactive search (CRIS) tool was used to carry out a retrospective study of 795 CHR-P individuals. Sleep problems, subsequent psychotic diagnoses, attenuated positive symptoms and Health of The Nation Outcome Scale scores were extracted. Regression models were used to examine the association between sleep problems and clinical outcomes.

RESULTS

59.5% of CHR-P individuals experienced sleep problems. Perceptual abnormality severity (OR = 1.24, 95% CI = 1.05-1.48) and frequency (OR = 1.31, 95% CI = 1.08-1.58) as measured by the Comprehensive Assessment of At-Risk Mental State interview, predicted sleep problems. Sleep problems were not associated with transition to psychosis; however, they were significantly associated with a shorter time to transition in individuals who developed psychosis (HR = 1.4, 95% CI = 1.05-1.88) and higher follow-up Health of the Nation Outcome Scale scores (MD = 2.26, 95% CI = 0.55-3.96).

CONCLUSIONS

The high prevalence of sleep problems, along with the association with positive symptoms and worse functioning, highlights the need for effective sleep interventions in this population. Further research is needed to better understand the relationship between sleep problems and transition to psychosis.

Cannabis use, self-perceived risk, perceived peer approval and parental attitudes among youth at clinical high-risk for psychosis

AIM

Cannabis use is associated with greater likelihood of psychosis. The relationship between attitudes about cannabis and use has not been examined in youth at clinical high-risk (CHR) for psychosis. Additionally, the shifting legal landscape can provide a valuable context for evaluating use and related attitudes.

METHODS

This study included 174 participants (44 CHR, 43 healthy control [HC] youth-parent dyads). Youth completed measures of self-reported cannabis use confirmed with a urinalysis, self-perceived risk and perceived peer attitudes. Parents reported attitudes about youth use. Legalization occurred halfway during a 5-year study in Colorado, providing an opportunity to cross-sectionally examine its role in use and attitudes.

RESULTS

Frequency of youth reporting cannabis use was significantly higher in CHR (69%) than control group (30%). Use in CHR group was associated with higher perceived peer approval (r = .57), increased parental permissiveness (r = .28) and lower self-perceived risk (r = -.26). Comparing samples participating pre and post-legalization, use remained stable within each group. Group differences in parental permissiveness shifted; trend toward decrease in permissiveness in CHR group (η²_partial  = .07) and a significant increase in HCs (η²_partial  = .16) were observed. Post-legalization, use in CHR group correlated with higher perceived peer approval (r = .64), lower self-perceived risk (r = -.51) and higher parental permissiveness (r = .35, trend).

CONCLUSIONS

Taken together, results indicate a relationship between self and peer/parental attitudes about cannabis and use in youth at CHR for psychosis. These factors are important to consider within the legalization context given the changes in parental attitudes and a stronger association between use and attitudes in this group post-legalization.

Conditional release and cannabis use: Concerns and challenges for community reintegration

This article, which serves as a perspective review, delves into the complexities of cannabis use among individuals preparing for or already on conditional release (CR). These complexities include an association between cannabis use and mental illness and dealing with the fact that the use of illicit substances, such as cannabis, is against CR rules, leading to potential revocation. A focus of this article is the deleterious effects cannabis and synthetic derivatives of cannabis can have for individuals on CR. The article concludes with six-specific recommendations for managing cannabis use in this population with a focus on careful and detailed risk assessments that considers the relationship between substance use and dangerousness, the role of protective factors, the need for a detailed conditional release plan, inpatient and community-based interventions aimed at increasing individual autonomy, and education on the dangers of cannabis use for both the treatment team and the insanity acquittee.

Lower-Risk Cannabis Use Guidelines (LRCUG) for reducing health harms from non-medical cannabis use: A comprehensive evidence and recommendations update

BACKGROUND

Cannabis use is common, especially among young people, and is associated with risks for various health harms. Some jurisdictions have recently moved to legalization/regulation pursuing public health goals. Evidence-based 'Lower Risk Cannabis Use Guidelines' (LRCUG) and recommendations were previously developed to reduce modifiable risk factors of cannabis-related adverse health outcomes; related evidence has evolved substantially since. We aimed to review new scientific evidence and to develop comprehensively up-to-date LRCUG, including their recommendations, on this evidence basis.

METHODS

Targeted searches for literature (since 2016) on main risk factors for cannabis-related adverse health outcomes modifiable by the user-individual were conducted. Topical areas were informed by previous LRCUG content and expanded upon current evidence. Searches preferentially focused on systematic reviews, supplemented by key individual studies. The review results were evidence-graded, topically organized and narratively summarized; recommendations were developed through an iterative scientific expert consensus development process.

RESULTS

A substantial body of modifiable risk factors for cannabis use-related health harms were identified with varying evidence quality. Twelve substantive recommendation clusters and three precautionary statements were developed. In general, current evidence suggests that individuals can substantially reduce their risk for adverse health outcomes if they delay the onset of cannabis use until after adolescence, avoid the use of high-potency (THC) cannabis products and high-frequency/-intensity of use, and refrain from smoking-routes for administration. While young people are particularly vulnerable to cannabis-related harms, other sub-groups (e.g., pregnant women, drivers, older adults, those with co-morbidities) are advised to exercise particular caution with use-related risks. Legal/regulated cannabis products should be used where possible.

CONCLUSIONS

Cannabis use can result in adverse health outcomes, mostly among sub-groups with higher-risk use. Reducing the risk factors identified can help to reduce health harms from use. The LRCUG offer one targeted intervention component within a comprehensive public health approach for cannabis use. They require effective audience-tailoring and dissemination, regular updating as new evidence become available, and should be evaluated for their impact.

Cannabidiol (CBD) as a novel treatment in the early phases of psychosis

The pharmacological interventions available for individuals in the early stages of psychosis are extremely limited. For those at clinical high risk for psychosis, there is no licensed treatment available. For those with first-episode psychosis, all licensed antipsychotic medications act via dopamine D₂ receptors. While treatment with antipsychotics is transformative in some patients, in others, it is ineffective. In addition, these medications can often cause adverse effects which make patients reluctant to take them. This is a particular problem in the early phases of psychosis, when patients are being treated for the first time, as unpleasant experiences may colour their future attitude towards treatment. Recent research has suggested that cannabidiol (CBD), a compound found in the Cannabis sativa plant, may have antipsychotic effects and relatively few adverse effects and could therefore be an ideal treatment for the early phases of psychosis, when minimising adverse effects is a clinical priority. In this review, we consider CBD's potential as a treatment in the clinical high risk and first-episode stages of psychosis. First, we describe the limitations of existing treatments at these two stages. We then describe what is known of CBD's mechanisms of action, effectiveness as a treatment for psychosis, adverse effects and acceptability to patients. We discuss how some of the outstanding issues about the utility of CBD in the early phases of psychosis may be resolved through ongoing clinical trials. Finally, we consider the impact of recreational cannabis use and over-the-counter cannabinoids preparations and discuss the potential therapeutic role of other compounds that modulate the endocannabinoid system in psychosis.

Schizotypy, Lifestyle Behaviors, and Health Indicators in a Young Adult Sample

Problematic lifestyle behaviors and high rates of physical illness are well documented in people with schizophrenia, contributing to premature mortality. Yet, there is a notable absence of research examining general lifestyle and health issues in participants at risk for psychosis. This form of research may help identify concerns that exist during prodromal periods related to future outcomes. Accordingly, the current study examined lifestyle and health in a nonclinical sample of 530 young adults with varying levels of schizotypy. Increasing symptom severity was associated with greater somatic symptoms and poorer sleep quality across positive, negative, and disorganized domains. Elevated negative and disorganized symptoms were associated with significantly reduced health-related quality of life, while evidence for reduced engagement in health behaviors was largely limited to those with elevated negative schizotypy. No relationships emerged between symptom presentation/severity and body mass index or substance use, although zero-order correlations suggested an association between disorganized schizotypy and nicotine use. The pattern of relationships in the current study was consistent with findings from the ultra-high risk and clinical literature suggesting that lifestyle and health concerns may exist on a continuum with psychosis. Future research should seek to clarify if these patterns are associated with long-term physical or mental health outcomes.

Overcoming the gap between child and adult mental health services: The Reggio Emilia experience in an early intervention in psychosis program

AIM

Early intervention in psychosis (EIP) can reduce severity and persistence of illness. From September 2012, the Reggio Emilia Department of Mental Health developed the 'Reggio Emilia At-Risk Mental States' (ReARMS) protocol as a specific EIP infrastructure in all its adult and child/adolescent mental health services. Aims of this study were (a) to describe the ReARMS macroscopic organization and (b) to analyse some specific process indicators (i.e., the amount of individuals referred to the ReARMS program, the number of subjects who met defined diagnostic criteria of early psychosis and accepted the intervention, and the 1-year drop-out rate) during the first 5 years of its clinical activity, in order to examine feasibility and quality of its procedures on the adolescent help-seeking subgroup.

METHODS

Adolescent participants (n = 125), aged 13-18 years, completed the Comprehensive Assessment of At-Risk Mental States (CAARMS) to investigate the clinical status. Descriptive quantitative analyses were then used.

RESULTS

Fifty (40%) individuals did not meet early psychosis-defined criteria, while 75 (60%: i.e., 44 Ultra-High Risk [UHR] and 31 First Episode Psychosis [FEP] subjects) were offered an EIP dedicated care protocol: of them, 66 (88%) were enrolled in the program and 9 (12%) dropped out during the first year of treatment). Adolescents enrolled in the ReARMS protocol were mainly referred by general practitioners (32%), family members (16%), or school/social services (15.2%). Seventy (56%) participants had a history of previous specialist contact (especially for learning and anxiety disorders).

CONCLUSIONS

An EIP program for adolescents with early psychosis in Italian child/adolescent mental health services are feasible, clinically relevant and recommended, specifically in this age group with a high risk of falling through the child/adult service gap.

A comparative study of complete blood count inflammatory markers in substance-free acute psychotic disorder and substance-induced psychosis

AIM

Recent studies showed a compare complete blood count (CBC) with its related measurements, including neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), and platelet to lymphocyte ratio, are a simple and affordable test for inflammatory markers. The aim of this controlled study is to compare CBC inflammatory markers in substance-induced psychosis (SIP) and substance-free acute psychotic disorder (SF-APD) and to evaluate whether these CBC inflammation values can be used in diagnosis.

METHODS

This retrospective study was conducted with the data of 76 SF-APD patients (including 60 cases of first-episode psychosis [FEP]), 98 SIP patients (including 48 cases of FEP), and 32 controls.

RESULTS

Patients with SF-APD and SIP had higher white blood cell counts, neutrophil and monocyte counts, and MLR than controls. An increased NLR was more distinct in SF-APD, while an increased MLR was observed in APD (both SF and SI) and FEP groups more than in the controls. A receiver operating characteristic analysis showed that the NLR could contribute to the identification of SF-APD (52.6% sensitivity and 12.5% specificity, area under curve [AUC] = 0.704, 2.47 cutoff value) while an MLR could contribute to the identification of APD (70.1% sensitivity and 12.5% specificity, AUC = 0.842) as well as FEP (71.3% sensitivity and 12.5% specificity AUC = 0.831) with 0.26 cutoff value.

CONCLUSIONS

An NLR and MLR might be of interest for inflammatory processes involved in acute and first-episode psychotic events, regardless of substance involvement.

General risks of harm with cannabinoids, cannabis, and cannabis-based medicine possibly relevant to patients receiving these for pain management: an overview of systematic reviews

ABSTRACT

The growing demand for improved pain treatments together with expanding legalization of, and access to, cannabinoids, cannabis, and cannabis-based medicines has intensified the focus on risk-benefit considerations in pain management. Given limited harms data from analgesic clinical trials, we conducted an overview of systematic reviews focused on all harms possibly relevant to patients receiving cannabinoids for pain management. This PROSPERO-registered, PRISMA-compliant systematic overview identified 79 reviews, encompassing over 2200 individual reports about psychiatric and psychosocial harms, cognitive/behavioral effects, motor vehicle accidents, cardiovascular, respiratory, cancer-related, maternal/fetal, and general harms. Reviews, and their included studies, were of variable quality. Available evidence suggests variable associations between cannabis exposure (ranging from monthly to daily use based largely on self-report) and psychosis, motor vehicle accidents, respiratory problems, and other harms. Most evidence comes from settings other than that of pain management (eg, nonmedicinal and experimental) but does signal a need for caution and more robust harms evaluation in future studies. Given partial overlap between patients receiving cannabinoids for pain management and individuals using cannabinoids for other reasons, lessons from the crisis of oversupply and overuse of opioids in some parts of the world emphasize the need to broadly consider harms evidence from real-world settings. The advancement of research on cannabinoid harms will serve to guide optimal approaches to the use of cannabinoids for pain management. In the meantime, this evidence should be carefully examined when making risk-benefit considerations about the use of cannabinoids, cannabis, and cannabis-based medicine for chronic pain.

Disrupted parahippocampal and midbrain function underlie slower verbal learning in adolescent-onset regular cannabis use

RATIONALE

Prolonged use of cannabis, the most widely used illicit drug worldwide, has been consistently associated with impairment in memory and verbal learning. Although the neurophysiological underpinnings of these impairments have been investigated previously using functional magnetic resonance imaging (fMRI), while performing memory tasks, the results of these studies have been inconsistent and no clear picture has emerged yet. Furthermore, no previous studies have investigated trial-by-trial learning.

OBJECTIVES

We aimed to investigate the neural underpinnings of impaired verbal learning in cannabis users as estimated over repeated learning trials.

METHODS

We studied 21 adolescent-onset regular cannabis users and 21 non-users using fMRI performed at least 12 h after last cannabis use, while they performed a paired associate verbal learning task that allowed us to examine trial-by-trial learning. Brain activation during repeated verbal encoding and recall conditions of the task was indexed using the blood oxygen level-dependent haemodynamic response fMRI signal.

RESULTS

There was a significant improvement in recall score over repeated trials indicating learning occurring across the two groups of participants. However, learning was significantly slower in cannabis users compared to non-users (p = 0.032, partial eta-squared = 0.108). While learning verbal stimuli over repeated encoding blocks, non-users displayed progressive increase in recruitment of the midbrain, parahippocampal gyrus and thalamus (p = 0.00939, partial eta-squared = 0.180). In contrast, cannabis users displayed a greater but disrupted activation pattern in these regions, which showed a stronger correlation with new word-pairs learnt over the same blocks in cannabis users than in non-users.

CONCLUSIONS

These results suggest that disrupted medial temporal and midbrain function underlie slower learning in adolescent-onset cannabis users.

The 'Parma-Early Psychosis' programme: Characterization of help-seekers with first episode psychosis

AIM

Research on early psychosis paradigm has demonstrated the importance of early intervention (EI) in reducing illness severity and persistence. From January 2013, the Parma Department of Mental Health developed a specific care pathway [the 'Parma-Early Psychosis' (Pr-EP) programme] as a diffused EI infrastructure aimed to offer an evidence-based protocol of care to help-seekers with a first episode psychosis (FEP). Aim of this study was to investigate sources of referral, drop-out rate, sociodemographic and clinical characteristics of patients enrolled in the Pr-EP programme during the first 6 years of activity.

METHODS

Participants (n = 279) were individuals (aged 12-54 years) completing an ad-hoc socio-demographic/clinical schedule.

RESULTS

At baseline, the most frequent diagnoses were schizophreniform disorder (30.5%) and schizophrenia (29.4%). Only 31 (11.1%) subjects dropped out during the first year of treatment. FEP participants were mainly referred by general practitioners (36.9%) and emergency room/general hospital (28.7%). FEP individuals who were referred by emergency room/general hospital showed a higher percentage of current suicidal ideation compared to those entering the Pr-EP protocol through other sources of referrals.

CONCLUSIONS

EI in FEP help-seekers within Italian public mental health services is feasible and desirable, also in adolescence, where the risk of falling through the child-adult service gap is high.

Attenuated Psychotic Symptoms in Adolescents With Chronic Cannabis and MDMA Use

OBJECTIVES

Both substance use, on the one hand, and the first signs of psychosis, on the other, commonly begin in adolescence. Adolescents with substance use disorder (SUD) frequently show recreational use of cannabis and 3,4-methylenedioxymethamphetamine (MDMA). When attenuated psychotic symptoms (APS) occur during the course of SUD, they are commonly attributed to the cannabis use, neglecting the role of other substances abused, such as MDMA in the risk of psychosis.

METHODS

We analyzed retrospective self-reports on APS (Prodromal Questionnaire, PQ-16) and amount of cannabis and MDMA use in n = 46 adolescent psychiatry outpatients with SUD. N = 17 (35%) individuals reported MDMA consume additional to cannabis. Furthermore, we examined the associations of APS with cannabis and MDMA use in stepwise hierarchical regressions while controlling for trauma history, birth complications and gender.

RESULTS

APS were not related to cannabis (B = 0.04, p = 0.842), but to MDMA use (B = 4.88, p = 0.001) and trauma history (B = 0.72, p = 0.001). Gender (B = -0.22, p = 0.767) and birth complications (B = -0.68, p = 0.178) were not associated with APS.

DISCUSSION

Our results indicate that MDMA use additional to cannabis use is associated with APS among adolescent SUD patients. Contrary to our expectations, we did not see an association of cannabis use and APS. We speculate that cannabis increases the risk for psychosis after a longer period of use and in combination with other risk factors, such as trauma history. Clinicians should screen for APS among SUD patients using MDMA and cannabis in order to adapt treatment plans of SUDs. Future research should validate these findings in longitudinal studies including polysubstance use and trauma history.

A Web-Based Program for Cannabis Use and Psychotic Experiences in Young People (Keep It Real): Protocol for a Randomized Controlled Trial

BACKGROUND

Young Australians (16-25 years) have the highest rates of past-month cannabis use in the world. Cannabis use increases the risk of alcohol and other drug disorders and depressive disorders, and has a robust dose-response association with psychotic experiences (PEs) and disorders. PEs are subthreshold positive psychotic symptoms, including delusions and hallucinations, which increase the risk of substance use, depressive or anxiety disorders, and psychotic disorders. Access to effective web-based early interventions targeting both cannabis use and PEs could reduce such risk in young people.

OBJECTIVE

The objective of this study is to determine the efficacy and cost-effectiveness of the Keep it Real web-based program compared to an information-only control website among young cannabis users (16-25 years) with PEs.

METHODS

Participants are recruited online, and consenting individuals meeting inclusion criteria (aged 16-25 years, who have used cannabis in the past month and experienced PEs in the past 3 months) are automatically randomized to either the Keep it Real web-based program (n=249) or an information-only control website (n=249). Both websites are self-guided (fully automated). The baseline and follow-up assessments at 3, 6, 9, and 12 months are self-completed online. Primary outcome measures are weekly cannabis use, PEs, and the relative cost-effectiveness for quality-adjusted life years. Secondary outcomes include other substance use and related problems, PE-related distress, cannabis intoxication experiences, severity of cannabis dependence, depression/anxiety symptoms, suicidality, and mental well-being and functioning.

RESULTS

Recruitment commenced in February 2019, and the results are expected to be submitted for publication in mid-2021.

CONCLUSIONS

This study protocol describes a large randomized controlled trial of a new web-based program for young cannabis users experiencing PEs. If effective, the accessibility and scalability of Keep it Real could help reduce growing public health concerns about the significant social, economic, and health impacts of cannabis use.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12618001107213; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374800.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/15803.

Derivation of poly-methylomic profile scores for schizophrenia

Schizophrenia and bipolar disorder share biological features and environmental risk factors that may be associated with altered DNA methylation. In this study we sought to: 1) construct a novel 'Poly-Methylomic Profile Score (PMPS)' by transforming schizophrenia-associated epigenome-wide methylation from a previously published epigenome-wide association study (EWAS) into a single quantitative metric; and 2) examine associations between the PMPS and clinical status in an independent sample of 57 schizophrenia (SZ) cases, 59 bipolar disorder (BD) cases and 55 healthy controls (HC) for whom blood-derived DNA methylation was quantified using the Illumina 450 K methylation beadchip. We constructed five PMPSs at different p-value thresholds by summing methylation beta-values weighted by individual-CpG effect sizes from the meta-analysis of a previously published schizophrenia EWAS (comprising three separate cohorts with 675 [353 SZ and 322 HC] discovery cohort participants, 847 [414 SZ and 433 HC] replication cohort participants, and 96 monozygotic twin-pairs discordant for SZ). All SZ PMPSs were elevated in SZ participants relative to HCs, with the score calculated at a p-value threshold of 1 × 10^-5 accounting for the greatest amount of variance. All PMPSs were elevated in SZ relative to BD and none of the PMPSs were increased in BD, or in a combined cohort of BD and SZ cases, relative to HCs. PMPSs were also not associated with positive or negative symptom severity. That this SZ-derived PMPSs was elevated in SZ, but not BD, suggests that epigenome-wide methylation patterns may represent distinct pathophysiology that is yet to be elucidated.

Prevention of Psychosis: Advances in Detection, Prognosis, and Intervention

IMPORTANCE

Detection, prognosis, and indicated interventions in individuals at clinical high risk for psychosis (CHR-P) are key components of preventive psychiatry.

OBJECTIVE

To provide a comprehensive, evidence-based systematic appraisal of the advancements and limitations of detection, prognosis, and interventions for CHR-P individuals and to formulate updated recommendations.

EVIDENCE REVIEW

Web of Science, Cochrane Central Register of Reviews, and Ovid/PsychINFO were searched for articles published from January 1, 2013, to June 30, 2019, to identify meta-analyses conducted in CHR-P individuals. MEDLINE was used to search the reference lists of retrieved articles. Data obtained from each article included first author, year of publication, topic investigated, type of publication, study design and number, sample size of CHR-P population and comparison group, type of comparison group, age and sex of CHR-P individuals, type of prognostic assessment, interventions, quality assessment (using AMSTAR [Assessing the Methodological Quality of Systematic Reviews]), and key findings with their effect sizes.

FINDINGS

In total, 42 meta-analyses published in the past 6 years and encompassing 81 outcomes were included. For the detection component, CHR-P individuals were young (mean [SD] age, 20.6 [3.2] years), were more frequently male (58%), and predominantly presented with attenuated psychotic symptoms lasting for more than 1 year before their presentation at specialized services. CHR-P individuals accumulated several sociodemographic risk factors compared with control participants. Substance use (33% tobacco use and 27% cannabis use), comorbid mental disorders (41% with depressive disorders and 15% with anxiety disorders), suicidal ideation (66%), and self-harm (49%) were also frequently seen in CHR-P individuals. CHR-P individuals showed impairments in work (Cohen d = 0.57) or educational functioning (Cohen d = 0.21), social functioning (Cohen d = 1.25), and quality of life (Cohen d = 1.75). Several neurobiological and neurocognitive alterations were confirmed in this study. For the prognosis component, the prognostic accuracy of CHR-P instruments was good, provided they were used in clinical samples. Overall, risk of psychosis was 22% at 3 years, and the risk was the highest in the brief and limited intermittent psychotic symptoms subgroup (38%). Baseline severity of attenuated psychotic (Cohen d = 0.35) and negative symptoms (Cohen d = 0.39) as well as low functioning (Cohen d = 0.29) were associated with an increased risk of psychosis. Controlling risk enrichment and implementing sequential risk assessments can optimize prognostic accuracy. For the intervention component, no robust evidence yet exists to favor any indicated intervention over another (including needs-based interventions and control conditions) for preventing psychosis or ameliorating any other outcome in CHR-P individuals. However, because the uncertainty of this evidence is high, needs-based and psychological interventions should still be offered.

CONCLUSIONS AND RELEVANCE

This review confirmed recent substantial advancements in the detection and prognosis of CHR-P individuals while suggesting that effective indicated interventions need to be identified. This evidence suggests a need for specialized services to detect CHR-P individuals in primary and secondary care settings, to formulate a prognosis with validated psychometric instruments, and to offer needs-based and psychological interventions.

Cannabis use and psychosis: a review of reviews

We conducted a systematic review of meta-analyses and systematic reviews to evaluate the impact of cannabis use on the onset and course of psychoses. Following a systematic literature search of five data bases (2005-2016) and consecutive structured evaluation, we were able to include 26 systematic reviews and meta-analyses. The methodological quality of the included publications were in the range of high and poor. The scientific literature indicates that psychotic illness arises more frequently in cannabis users compared to non-users, cannabis use is associated with a dose-dependent risk of developing psychotic illness, and cannabis users have an earlier onset of psychotic illness compared to non-users. Cannabis use was also associated with increased relapse rates, more hospitalizations and pronounced positive symptoms in psychotic patients. We make recommendations about the type of research that is required to better characterize the relationship between cannabis use and the development and outcomes of psychosis.

The "Parma-Early Psychosis" program: General description and process analysis after 5 years of clinical activity

AIM

From January 2013, the Parma Department of Mental Health developed a specific protocol of care (the "Parma-Early Psychosis" [Pr-EP] program) as a diffused service for early intervention in psychosis. The aims of the present research are (a) to describe the Pr-EP macroscopic organization and (b) to analyse specific process indicators across the first 5 years from its establishment.

METHODS

All participants were adolescent and adult help-seekers, aged 12-54 years, with a First Episode Psychosis (FEP) or at Ultra-High Risk for developing psychosis, according to well-defined diagnostic criteria.

RESULTS

At baseline, 358 individuals were offered a dedicated protocol of care and only 40 (11.8%) dropped out during the first year of intervention. In particular, an increase of referrals over time was notably found (especially in adolescence). Furthermore, Duration of Untreated Psychosis decreased over time. The baseline prevalence of FEP diagnosis was 61.4%, with schizophrenia as markedly prevalent Diagnostic and Statistical Manual of mental disorders, IV edition, Text Revised (DSM-IV-TR) diagnosis (41%). The vast majority of UHR individuals met criteria for "Attenuated Psychotic Symptoms" (>90%), and major depressive disorder was the most frequent diagnosis (>55%). Finally, we found considerable percentages of current history of substance abuse (>58%) and of comorbidity with DSM-IV-TR personality disorders (60%).

CONCLUSIONS

An "Early Intervention in psychosis" service in Italian child/adolescent and adult mental health services is feasible, also in adolescents, who have a high risk of falling through the child-adult service gap.

Cannabis use in individuals at clinical high-risk for psychosis: a comprehensive review

PURPOSE

The objectives of this review were to understand the prevalence of cannabis use and how cannabis is associated with transition to psychosis, symptoms, cognition, trauma and family history in clinical high risk (CHR) for psychosis individuals.

METHOD

A systematic literature review was conducted to find studies that examined cannabis use in CHR individuals, with no limitations on the geographical area, and included publications up to November 2018. Studies were screened for inclusion based on detailed criteria, and data were extracted on cannabis use and associated outcomes. A quantitative synthesis by meta-analysis was performed where appropriate, otherwise, a qualitative synthesis was conducted.

RESULTS

Overall, 36 studies met inclusion criteria with an average age of 20.1 years and 58.4% males. Prevalence of lifetime cannabis use was 48.7%, whereas current cannabis use was 25.8% and the prevalence of cannabis use disorder/abuse or dependence was 14.9% across the studies. All cannabis use results had statistically significant heterogeneity ranging from 75.7 to 92.8%. The most commonly reported association with cannabis use was transition to psychosis, although the pooled relative risk (RR) was not statistically significant (RR = 1.11, 95% confidence interval = 0.89-1.37). For all other outcomes including symptoms, cognition, trauma, and family history, the evidence was limited, and therefore, the results were synthesized qualitatively.

CONCLUSION

Almost half of CHR individuals have ever used cannabis. However, cannabis use has not been thoroughly researched regarding frequency and dose of use, and how other factors, such as symptoms, are associated with cannabis in CHR individuals.

The blind men and the elephant: Systematic review of systematic reviews of cannabis use related health harms

Cannabis is the third most used psychoactive substance worldwide. The legal status of cannabis is changing in many Western countries, while we have very limited knowledge of the public health impact of cannabis-related harms. There is a need for a summary of the evidence of harms and risks attributed to cannabis use, in order to inform the definition of cannabis risky use. We have conducted a systematic review of systematic reviews, aiming to define cannabis-related harms. We included systematic reviews published until July 2018 from six different databases and following the PRISMA guidelines. To assess study quality we applied the AMSTAR 2 tool. A total of 44 systematic reviews, including 1,053 different studies, were eligible for inclusion. Harm was categorized in three dimensions: mental health, somatic harm and physical injury (including mortality). Evidence shows a clear association between cannabis use and psychosis, affective disorders, anxiety, sleep disorders, cognitive failures, respiratory adverse events, cancer, cardiovascular outcomes, and gastrointestinal disorders. Moreover, cannabis use is a risk factor for motor vehicle collision, suicidal behavior and partner and child violence. Cannabis use is a risk factor for several medical conditions and negative social consequences. There is still little data on the dose-dependency of these effects; evidence that is essential in order to define, from a public health perspective, what can be considered risky use of cannabis. This definition should be based on quantitative and qualitative criteria that informs and permits the evaluation of current approaches to a regulated cannabis market.

Substance use disorders before, at and after first episode psychosis hospitalizations in a young national Swedish cohort

BACKGROUND

Comorbidity between Substance use disorders (SUD) and psychotic disorders is common but the temporal relation of the first episodes of SUD and psychosis and how it affects the disorders has not been extensively investigated.

METHODS

A nation-wide cohort (n = 2494) with a first hospitalization for psychosis at ages between 16 and 25 was identified. Psychiatric hospitalizations were followed from birth until up to 5 years after the first psychosis hospitalization. Risk factors for new SUD or psychosis hospitalization after the index hospitalization were analyzed by Cox regression.

RESULTS

30 % of the cases had SUD hospitalizations in the 5 years before or as a comorbid diagnosis at the first psychosis hospitalization. An additional 9% had a first SUD hospitalization in the five years after. The incidence of SUD hospitalizations increased year by year before and decrease year by year after the index hospitalization. The hazard ratio for a new SUD hospitalizations after the index hospitalization was significantly higher (hazard ratio 6.7, p-value<0.001) in cases with SUD before or at the index hospitalization compared to in cases without previous SUD. In cases with previous SUD, there was a strong association (p < 0.001) between a new psychosis hospitalization and a new SUD hospitalization the year after the index hospitalization, indicating that SUD may continue to aggravate the psychotic disorder in this group.

CONCLUSIONS

SUD is very common before a first hospital treated psychosis. The SUD likely aggravates early psychotic disorders in many cases.

Factors Moderating the Association Between Cannabis Use and Psychosis Risk: A Systematic Review

Increasing evidence indicates a relationship between cannabis use and psychosis risk. Specific factors, such as determinants of cannabis use or the genetic profile of cannabis users, appear to moderate this association. The present systematic review presents a detailed and up-to-date literature overview on factors that influence the relationship between cannabis use and psychosis risk. A systematic search was performed according to the PRISMA guidelines in MEDLINE and Embase, and 56 studies were included. The results show that, in particular, frequent cannabis use, especially daily use, and the consumption of high-potency cannabis are associated with a higher risk of developing psychosis. Moreover, several genotypes moderate the impact of cannabis use on psychosis risk, particularly those involved in the dopamine function, such as AKT1. Finally, cannabis use is associated with an earlier psychosis onset and increased risk of transition in individuals at a clinical high risk of psychosis. These findings indicate that changing cannabis use behavior could be a harm reduction strategy employed to lower the risk of developing psychosis. Future research should aim to further develop specific biomarkers and genetic profiles for psychosis, thereby contributing to the identification of individuals at the highest risk of developing a psychotic disorder.

Medicinal cannabis for psychiatric disorders: a clinically-focused systematic review

BACKGROUND

Medicinal cannabis has received increased research attention over recent years due to loosening global regulatory changes. Medicinal cannabis has been reported to have potential efficacy in reducing pain, muscle spasticity, chemotherapy-induced nausea and vomiting, and intractable childhood epilepsy. Yet its potential application in the field of psychiatry is lesser known.

METHODS

The first clinically-focused systematic review on the emerging medical application of cannabis across all major psychiatric disorders was conducted. Current evidence regarding whole plant formulations and plant-derived cannabinoid isolates in mood, anxiety, sleep, psychotic disorders and attention deficit/hyperactivity disorder (ADHD) is discussed; while also detailing clinical prescription considerations (including pharmacogenomics), occupational and public health elements, and future research recommendations. The systematic review of the literature was conducted during 2019, assessing the data from all case studies and clinical trials involving medicinal cannabis or plant-derived isolates for all major psychiatric disorders (neurological conditions and pain were omitted).

RESULTS

The present evidence in the emerging field of cannabinoid therapeutics in psychiatry is nascent, and thereby it is currently premature to recommend cannabinoid-based interventions. Isolated positive studies have, however, revealed tentative support for cannabinoids (namely cannabidiol; CBD) for reducing social anxiety; with mixed (mainly positive) evidence for adjunctive use in schizophrenia. Case studies suggest that medicinal cannabis may be beneficial for improving sleep and post-traumatic stress disorder, however evidence is currently weak. Preliminary research findings indicate no benefit for depression from high delta-9 tetrahydrocannabinol (THC) therapeutics, or for CBD in mania. One isolated study indicates some potential efficacy for an oral cannabinoid/terpene combination in ADHD. Clinical prescriptive consideration involves caution in the use of high-THC formulations (avoidance in youth, and in people with anxiety or psychotic disorders), gradual titration, regular assessment, and caution in cardiovascular and respiratory disorders, pregnancy and breast-feeding.

CONCLUSIONS

There is currently encouraging, albeit embryonic, evidence for medicinal cannabis in the treatment of a range of psychiatric disorders. Supportive findings are emerging for some key isolates, however, clinicians need to be mindful of a range of prescriptive and occupational safety considerations, especially if initiating higher dose THC formulas.

First Episode Psychosis Medical Workup: Evidence-Informed Recommendations and Introduction to a Clinically Guided Approach

Evaluating the patient with first episode psychosis (FEP) requires a careful assessment that includes a thorough history, examination, and workup. This begins with a thoughtful consideration of the differential diagnoses and is followed and supported by laboratory, encephalographic, and imaging studies where appropriate. This article presents some of the diagnostic considerations for a patient presenting with psychosis with an emphasis on the secondary causes and proposes a tiered approach to the workup of FEP that is clinically guided.