Associations between disturbed sleep and attenuated psychotic experiences in people at clinical high risk for psychosis.

BACKGROUND: Pre-diagnostic stages of psychotic illnesses, including 'clinical high risk' (CHR), are marked by sleep disturbances. These sleep disturbances appear to represent a key aspect in the etiology and maintenance of psychotic disorders. We aimed to examine the relationship between self-reported sleep dysfunction and attenuated psychotic symptoms (APS) on a day-to-day basis. METHODS: Seventy-six CHR young people completed the Experience Sampling Methodology (ESM) component of the European Union Gene-Environment Interaction Study, collected through PsyMate® devices, prompting sleep and symptom questionnaires 10 times daily for 6 days. Bayesian multilevel mixed linear regression analyses were performed on time-variant ESM data using the brms package in R. We investigated the day-to-day associations between sleep and psychotic experiences bidirectionally on an item level. Sleep items included sleep onset latency, fragmentation, and quality. Psychosis items assessed a range of perceptual, cognitive, and bizarre thought content common in the CHR population. RESULTS: Two of the seven psychosis variables were unidirectionally predicted by previous night's number of awakenings: every unit increase in number of nightly awakenings predicted a 0.27 and 0.28 unit increase in feeling unreal or paranoid the next day, respectively. No other sleep variables credibly predicted next-day psychotic symptoms or vice-versa. CONCLUSION: In this study, the relationship between sleep disturbance and APS appears specific to the item in question. However, some APS, including perceptual disturbances, had low levels of endorsement amongst this sample. Nonetheless, these results provide evidence for a unidirectional relationship between sleep and some APS in this population.

Virtual reality in the assessment and treatment of psychosis: a systematic review of its utility, acceptability and effectiveness.

Over the last two decades, there has been a rapid increase of studies testing the efficacy and acceptability of virtual reality in the assessment and treatment of mental health problems. This systematic review was carried out to investigate the use of virtual reality in the assessment and the treatment of psychosis. Web of Science, PsychInfo, EMBASE, Scopus, ProQuest and PubMed databases were searched, resulting in the identification of 638 articles potentially eligible for inclusion; of these, 50 studies were included in the review. The main fields of research in virtual reality and psychosis are: safety and acceptability of the technology; neurocognitive evaluation; functional capacity and performance evaluation; assessment of paranoid ideation and auditory hallucinations; and interventions. The studies reviewed indicate that virtual reality offers a valuable method of assessing the presence of symptoms in ecologically valid environments, with the potential to facilitate learning new emotional and behavioural responses. Virtual reality is a promising method to be used in the assessment of neurocognitive deficits and the study of relevant clinical symptoms. Furthermore, preliminary findings suggest that it can be applied to the delivery of cognitive rehabilitation, social skills training interventions and virtual reality-assisted therapies for psychosis. The potential benefits for enhancing treatment are highlighted. Recommendations for future research include demonstrating generalisability to real-life settings, examining potential negative effects, larger sample sizes and long-term follow-up studies. The present review has been registered in the PROSPERO register: CDR 4201507776.

Interpersonal sensitivity and persistent attenuated psychotic symptoms in adolescence.

Interpersonal sensitivity defines feelings of inner-fragility in the presence of others due to the expectation of criticism or rejection. Interpersonal sensitivity was found to be related to attenuated positive psychotic symptom during the prodromal phase of psychosis. The aims of this study were to examine if high level of interpersonal sensitivity at baseline are associated with the persistence of attenuated positive psychotic symptoms and general psychopathology at 18-month follow-up. A sample of 85 help-seeking individuals (mean age = 16.6, SD = 5.05) referred an Italian early detection project, completed the interpersonal sensitivity measure and the structured interview for prodromal symptoms (SIPS) at baseline and were assessed at 18-month follow-up using the SIPS. Results showed that individuals with high level of interpersonal sensitivity at baseline reported high level of attenuated positive psychotic symptoms (i.e., unusual thought content) and general symptoms (i.e., depression, irritability and low tolerance to daily stress) at follow-up. This study suggests that being "hypersensitive" to interpersonal interactions is a psychological feature associated with attenuated positive psychotic symptoms and general symptoms, such as depression and irritability, at 18-month follow-up. Assessing and treating inner-self fragilities may be an important step of early detection program to avoid the persistence of subtle but very distressing long-terms symptoms.

Psychological processes underlying the association between childhood trauma and psychosis in daily life: an experience sampling study.

BACKGROUND: Evidence has accumulated that implicates childhood trauma in the aetiology of psychosis, but our understanding of the putative psychological processes and mechanisms through which childhood trauma impacts on individuals and contributes to the development of psychosis remains limited. We aimed to investigate whether stress sensitivity and threat anticipation underlie the association between childhood abuse and psychosis. METHOD: We used the Experience Sampling Method to measure stress, threat anticipation, negative affect, and psychotic experiences in 50 first-episode psychosis (FEP) patients, 44 At-Risk Mental State (ARMS) participants, and 52 controls. Childhood abuse was assessed using the Childhood Trauma Questionnaire. RESULTS: Associations of minor socio-environmental stress in daily life with negative affect and psychotic experiences were modified by sexual abuse and group (all p FWE < 0.05). While there was strong evidence that these associations were greater in FEP exposed to high levels of sexual abuse, and some evidence of greater associations in ARMS exposed to high levels of sexual abuse, controls exposed to high levels of sexual abuse were more resilient and reported less intense negative emotional reactions to socio-environmental stress. A similar pattern was evident for threat anticipation. CONCLUSIONS: Elevated sensitivity and lack of resilience to socio-environmental stress and enhanced threat anticipation in daily life may be important psychological processes underlying the association between childhood sexual abuse and psychosis.

Services for people at high risk improve outcomes in patients with first episode psychosis.

OBJECTIVE: About one-third of patients referred to services for people at high risk for psychosis may have already developed a first episode of psychosis (FEP). We compared clinical outcomes in FEP patients who presented to either high risk or conventional mental health services. METHOD: Retrospective study comparing duration of hospital admission, referral-to-diagnosis time, need for compulsory hospital admission and frequency of admission in patients with FEP who initially presented to a high-risk service (n = 164) to patients with FEP who initially presented to conventional mental health services (n = 2779). Regression models were performed, controlling for several confounders. RESULTS: FEP patients who had presented to a high-risk service spent 17 fewer days in hospital [95% CI: -33.7 to (-0.3)], had a shorter referral-to-diagnosis time [B coefficient -74.5 days, 95% CI: -101.9 to -(47.1)], a lower frequency of admission [IRR: 0.49 (95% CI: 0.39-0.61)] and a lower likelihood of compulsory admission [OR: 0.52 (95% CI: 0.34-0.81)] in the 24 months following referral, as compared to FEP patients who were first diagnosed at conventional services. CONCLUSION: Services for people at high risk for psychosis are associated with better clinical outcomes in patients who are already psychotic.

Interpersonal sensitivity and functioning impairment in youth at ultra-high risk for psychosis.

A personality trait that often elicits poor and uneasy interpersonal relationships is interpersonal sensitivity. The aim of the present study was to explore the relationship between interpersonal sensitivity and psychosocial functioning in individuals at ultra-high risk for psychosis as compared to help-seeking individuals who screened negative for an ultra-high risk of psychosis. A total sample of 147 adolescents and young adult who were help seeking for emerging mental health problems participated in the study. The sample was divided into two groups: 39 individuals who met criteria for an ultra-high-risk mental state (UHR), and 108 (NS). The whole sample completed the Interpersonal Sensitivity Measure (IPSM) and the Global Functioning: Social and Role Scale (GF:SS; GF:RS). Mediation analysis was used to explore whether attenuated negative symptoms mediated the relationship between interpersonal sensitivity and social functioning. Individuals with UHR state showed higher IPSM scores and lower GF:SS and GF:RS scores than NS participants. A statistically negative significant correlation between two IPSM subscales (Interpersonal Awareness and Timidity) and GF:SS was found in both groups. Our results also suggest that the relationship between the aforementioned aspects of interpersonal sensitivity and social functioning was not mediated by negative prodromal symptoms. This study suggests that some aspects of interpersonal sensitivity were associated with low level of social functioning. Assessing and treating interpersonal sensitivity may be a promising therapeutic target to improve social functioning in young help-seeking individuals.

Antidepressant, antipsychotic and psychological interventions in subjects at high clinical risk for psychosis: OASIS 6-year naturalistic study.

BACKGROUND: Recent randomized controlled trials suggest some efficacy for focused interventions in subjects at high risk (HR) for psychosis. However, treating HR subjects within the real-world setting of prodromal services is hindered by several practical problems that can significantly make an impact on the effect of focused interventions. METHOD: All subjects referred to Outreach and Support in South London (OASIS) and diagnosed with a HR state in the period 2001-2012 were included (n = 258). Exposure to focused interventions was correlated with sociodemographic and clinical characteristics at baseline. Their association with longitudinal clinical and functional outcomes was addressed at follow-up. RESULTS: In a mean follow-up time of 6 years (s.d. = 2.5 years) a transition risk of 18% was observed. Of the sample, 33% were treated with cognitive behavioural therapy (CBT) only; 17% of subjects received antipsychotics (APs) in addition to CBT sessions. Another 17% of subjects were prescribed with antidepressants (ADs) in addition to CBT. Of the sample, 20% were exposed to a combination of interventions. Focused interventions had a significant relationship with transition to psychosis. The CBT + AD intervention was associated with a reduced risk of transition to psychosis, as compared with the CBT + AP intervention (hazards ratio = 0.129, 95% confidence interval 0.030-0.565, p = 0.007). CONCLUSIONS: There were differential associations with transition outcome for AD v. AP interventions in addition to CBT in HR subjects. These effects were not secondary to baseline differences in symptom severity.

Are we really mapping psychosis risk? Neuroanatomical signature of affective disorders in subjects at ultra high risk.

BACKGROUND: The majority of people at ultra high risk (UHR) of psychosis also present with co-morbid affective disorders such as depression or anxiety. The neuroanatomical and clinical impact of UHR co-morbidity is unknown. METHOD: We investigated group differences in grey matter volume using baseline magnetic resonance images from 121 participants in four groups: UHR with depressive or anxiety co-morbidity; UHR alone; major depressive disorder; and healthy controls. The impact of grey matter volume on baseline and longitudinal clinical/functional data was assessed with regression analyses. RESULTS: The UHR-co-morbidity group had lower grey matter volume in the anterior cingulate cortex than the UHR-alone group, with an intermediate effect between controls and patients with major depressive disorder. In the UHR-co-morbidity group, baseline anterior cingulate volume was negatively correlated with baseline suicidality/self-harm and obsessive-compulsive disorder symptoms. CONCLUSIONS: Co-morbid depression and anxiety disorders contributed distinctive grey matter volume reductions of the anterior cingulate cortex in people at UHR of psychosis. These volumetric deficits were correlated with baseline measures of depression and anxiety, suggesting that co-morbid depressive and anxiety diagnoses should be carefully considered in future clinical and imaging studies of the psychosis high-risk state.

Cannabis use and transition to psychosis in people at ultra-high risk.

BACKGROUND: Cannabis use is associated with an increased risk of developing a psychotic disorder but the temporal relationship between cannabis use and onset of illness is unclear. The objective of this study was to assess prospectively the influence of cannabis use on transition to psychosis in people at ultra-high risk (UHR) for the disorder. METHOD: Lifetime and continued cannabis use was assessed in a consecutively ascertained sample of 182 people (104 male, 78 female) at UHR for psychosis. Individuals were then followed clinically for 2 years to determine their clinical outcomes. RESULTS: Lifetime cannabis use was reported by 134 individuals (73.6%). However, most of these individuals had stopped using cannabis before clinical presentation (n=98, 73.1%), usually because of adverse effects. Among lifetime users, frequent use, early-onset use and continued use after presentation were all associated with an increase in transition to psychosis. Transition to psychosis was highest among those who started using cannabis before the age of 15 years and went on to use frequently (frequent early-onset use: 25%; infrequent or late-onset use: 5%; χ(2)1=10.971, p=0.001). However, within the whole sample, cannabis users were no more likely to develop psychosis than those who had never used cannabis (cannabis use: 12.7%; no use: 18.8%; χ(2)1=1.061, p=0.303). CONCLUSIONS: In people at UHR for psychosis, lifetime cannabis use was common but not related to outcome. Among cannabis users, frequent use, early-onset use and continued use after clinical presentation were associated with transition to psychosis.

Increased stress reactivity: a mechanism specifically associated with the positive symptoms of psychotic disorder.

BACKGROUND: An increased reactivity to stress in the context of daily life is suggested to be an independent risk factor underlying the positive symptoms of psychotic disorder. The aim of this study was to investigate whether positive symptoms moderate the association between everyday stressful events and negative affect (NA), known as stress reactivity. This hypothesis was put to the test in patients with a diagnosis of psychotic disorder. Method The Comprehensive Assessment of Symptoms and History (CASH) and the Positive and Negative Syndrome Scale (PANSS) were used to assess positive and negative symptoms. The experience sampling method (ESM), a structured diary technique, was used to measure stress reactivity and psychotic symptoms in daily life. RESULTS: Higher levels of positive symptoms (CASH: B = 0.14, p = 0.005; PANSS: B = 0.05, p = 0.000; ESM: B = 0.03, p = 0.000) and lower levels of negative symptoms (PANSS: B = - 0.05, p = 0.001) significantly moderate the association between unpleasant events and NA. No significant moderating effect was found for CASH negative symptoms. Moreover, the moderating effect of lifetime and current symptoms on the stress-NA association was significantly larger for those patients with predominantly positive symptoms (CASH: B = 0.09, p = 0.000; PANSS: B = 0.08, p = 0.000; ESM: B = 0.13, p = 0.000). CONCLUSIONS: Patients with a 'psychotic syndrome' with high levels of positive symptoms and low levels of negative symptoms show increased reactivity to stress in daily life, indicating that stress reactivity is a possible risk factor underlying this syndrome.

Negative psychotic symptoms and impaired role functioning predict transition outcomes in the at-risk mental state: a latent class cluster analysis study.

BACKGROUND: Many research groups have attempted to predict which individuals with an at-risk mental state (ARMS) for psychosis will later develop a psychotic disorder. However, it is difficult to predict the course and outcome based on individual symptoms scores. METHOD: Data from 318 ARMS individuals from two specialized services for ARMS subjects were analysed using latent class cluster analysis (LCCA). The score on the Comprehensive Assessment of At-Risk Mental States (CAARMS) was used to explore the number, size and symptom profiles of latent classes. RESULTS: LCCA produced four high-risk classes, censored after 2 years of follow-up: class 1 (mild) had the lowest transition risk (4.9%). Subjects in this group had the lowest scores on all the CAARMS items, they were younger, more likely to be students and had the highest Global Assessment of Functioning (GAF) score. Subjects in class 2 (moderate) had a transition risk of 10.9%, scored moderately on all CAARMS items and were more likely to be in employment. Those in class 3 (moderate-severe) had a transition risk of 11.4% and scored moderately severe on the CAARMS. Subjects in class 4 (severe) had the highest transition risk (41.2%), they scored highest on the CAARMS, had the lowest GAF score and were more likely to be unemployed. Overall, class 4 was best distinguished from the other classes on the alogia, avolition/apathy, anhedonia, social isolation and impaired role functioning. CONCLUSIONS: The different classes of symptoms were associated with significant differences in the risk of transition at 2 years of follow-up. Symptomatic clustering predicts prognosis better than individual symptoms.

Interpersonal sensitivity in the at-risk mental state for psychosis.

BACKGROUND: Interpersonal sensitivity is a personality trait described as excessive awareness of both the behaviour and feelings of others. Although interpersonal sensitivity has been found to be one of the vulnerability factors to depression, there has been little interest in its relationship with the prodromal phase of psychosis. The aims of this study were to examine the level of interpersonal sensitivity in a sample of individuals with an at-risk mental state (ARMS) for psychosis and its relationship with other psychopathological features. METHOD: Sixty-two individuals with an ARMS for psychosis and 39 control participants completed a series of self-report questionnaires, including the Interpersonal Sensitivity Measure (IPSM), the Prodromal Questionnaire (PQ), the Ways of Coping Questionnaire (WCQ) and the Depression and Anxiety Stress Scale (DASS). RESULTS: Individuals with an ARMS reported higher interpersonal sensitivity compared to controls. Associations between interpersonal sensitivity, positive psychotic symptoms (i.e. paranoid ideation), avoidant coping and symptoms of depression, anxiety and stress were also found. CONCLUSIONS: This study suggests that being 'hypersensitive' to interpersonal interactions is a psychological feature of the putatively prodromal phase of psychosis. The relationship between interpersonal sensitivity, attenuated positive psychotic symptoms, avoidant coping and negative emotional states may contribute to long-term deficits in social functioning. We illustrate the importance, when assessing a young client with a possible ARMS, of examining more subtle and subjective symptoms in addition to attenuated positive symptoms.

Outreach and Support in South London (OASIS). Outcomes of non-attenders to a service for people at high risk of psychosis: the case for a more assertive approach to assessment.

BACKGROUND: International agreement dictates that clients must be help-seeking before any assessment or intervention can be implemented by an 'at-risk service'. Little is known about individuals who decline input. This study aimed to define the size of the unengaged population of an 'at-risk service', to compare this group to those who did engage in terms of sociodemographic and clinical features and to assess the clinical outcomes of those who did not engage with the service. METHOD: Groups were compared using data collected routinely as part of the service's clinical protocol. Data on service use and psychopathology since referral to Outreach and Support in South London (OASIS) were collected indirectly from clients' general practitioners (GPs) and by screening electronic patient notes held by the local Mental Health Trust. RESULTS: Over one-fifth (n=91, 21.2%) of those referred did not attend or engage with the service. Approximately half of this group subsequently received a diagnosis of mental illness. A diagnosis of psychosis was given to 22.6%. Nearly 70% presented to other mental health services. There were no demographic differences, except that those who engaged with the service were more likely to be employed. CONCLUSIONS: Over one-fifth of those referred to services for people at high risk of psychosis do not attend or engage. However, many of this group require mental health care, and a substantial proportion has, or will later develop, psychosis. A more assertive approach to assessing individuals who are at high risk of psychosis but fail to engage may be indicated.

Stress reactivity as a putative mechanism linking childhood trauma with clinical outcomes in individuals at ultra-high-risk for psychosis: Findings from the EU-GEI High Risk Study.

AIMS: Childhood trauma is associated with an elevated risk for psychosis, but the psychological mechanisms involved remain largely unclear. This study aimed to investigate emotional and psychotic stress reactivity in daily life as a putative mechanism linking childhood trauma and clinical outcomes in individuals at ultra-high-risk (UHR) for psychosis. METHODS: Experience sampling methodology was used to measure momentary stress, affect and psychotic experiences in the daily life of N = 79 UHR individuals in the EU-GEI High Risk Study. The Childhood Trauma Questionnaire was used to assess self-reported childhood trauma. Clinical outcomes were assessed at baseline, 1- and 2-year follow-up. RESULTS: The association of stress with positive (ß = -0.14, p = 0.010) and negative affect (ß = 0.11, p = 0.020) was modified by transition status such that stress reactivity was greater in individuals who transitioned to psychosis. Moreover, the association of stress with negative affect (ß = 0.06, p = 0.019) and psychotic experiences (ß = 0.05, p = 0.037) was greater in individuals exposed to high v. low levels of childhood trauma. We also found evidence that decreased positive affect in response to stress was associated with reduced functioning at 1-year follow-up (B = 6.29, p = 0.034). In addition, there was evidence that the association of childhood trauma with poor functional outcomes was mediated by stress reactivity (e.g. indirect effect: B = -2.13, p = 0.026), but no evidence that stress reactivity mediated the association between childhood trauma and transition (e.g. indirect effect: B = 0.14, p = 0.506). CONCLUSIONS: Emotional and psychotic stress reactivity may be potential mechanisms linking childhood trauma with clinical outcomes in UHR individuals.

Neural correlates of visuospatial working memory in the 'at-risk mental state'.

BACKGROUND: Impaired spatial working memory (SWM) is a robust feature of schizophrenia and has been linked to the risk of developing psychosis in people with an at-risk mental state (ARMS). We used functional magnetic resonance imaging (fMRI) to examine the neural substrate of SWM in the ARMS and in patients who had just developed schizophrenia. METHOD: fMRI was used to study 17 patients with an ARMS, 10 patients with a first episode of psychosis and 15 age-matched healthy comparison subjects. The blood oxygen level-dependent (BOLD) response was measured while subjects performed an object-location paired-associate memory task, with experimental manipulation of mnemonic load. RESULTS: In all groups, increasing mnemonic load was associated with activation in the medial frontal and medial posterior parietal cortex. Significant between-group differences in activation were evident in a cluster spanning the medial frontal cortex and right precuneus, with the ARMS groups showing less activation than controls but greater activation than first-episode psychosis (FEP) patients. These group differences were more evident at the most demanding levels of the task than at the easy level. In all groups, task performance improved with repetition of the conditions. However, there was a significant group difference in the response of the right precuneus across repeated trials, with an attenuation of activation in controls but increased activation in FEP and little change in the ARMS. CONCLUSIONS: Abnormal neural activity in the medial frontal cortex and posterior parietal cortex during an SWM task may be a neural correlate of increased vulnerability to psychosis.

Neural correlates of movement generation in the 'at-risk mental state'.

OBJECTIVE: People with 'prodromal' symptoms have a very high risk of developing psychosis. We examined the neurocognitive basis of this vulnerability by using functional MRI to study subjects with an at-risk mental state (ARMS) while they performed a random movement generation task. METHOD: Cross-sectional comparison of individuals with an ARMS (n = 17), patients with first episode schizophreniform psychosis (n = 10) and healthy volunteers (n = 15). Subjects were studied using functional MRI while they performed a random movement generation paradigm. RESULTS: During random movement generation, the ARMS group showed less activation in the left inferior parietal cortex than controls, but greater activation than in the first episode group. CONCLUSION: The ARMS is associated with abnormalities of regional brain function that are qualitatively similar to those in patients who have recently presented with psychosis but less severe.

Effects of short-term cannabidiol treatment on response to social stress in subjects at clinical high risk of developing psychosis.

RATIONALE: Stress is a risk factor for psychosis and treatments which mitigate its harmful effects are needed. Cannabidiol (CBD) has antipsychotic and anxiolytic effects. OBJECTIVES: We investigated whether CBD would normalise the neuroendocrine and anxiety responses to stress in clinical high risk for psychosis (CHR) patients. METHODS: Thirty-two CHR patients and 26 healthy controls (HC) took part in the Trier Social Stress Test (TSST) and their serum cortisol, anxiety and stress associated with public speaking were estimated. Half of the CHR participants were on 600 mg/day of CBD (CHR-CBD) and half were on placebo (CHR-P) for 1 week. RESULTS: One-way analysis of variance (ANOVA) revealed a significant effect of group (HC, CHR-P, CHR-CBD (p = .005) on cortisol reactivity as well as a significant (p = .003) linear decrease. The change in cortisol associated with experimental stress exposure was greatest in HC controls and least in CHR-P patients, with CHR-CBD patients exhibiting an intermediate response. Planned contrasts revealed that the cortisol reactivity was significantly different in HC compared with CHR-P (p = .003), and in HC compared with CHR-CBD (p = .014), but was not different between CHR-P and CHR-CBD (p = .70). Across the participant groups (CHR-P, CHR-CBD and HC), changes in anxiety and experience of public speaking stress (all p's < .02) were greatest in the CHR-P and least in the HC, with CHR-CBD participants demonstrating an intermediate level of change. CONCLUSIONS: Our findings show that it is worthwhile to design further well powered studies which investigate whether CBD may be used to affect cortisol response in clinical high risk for psychosis patients and any effect this may have on symptoms.

Duration of untreated prodromal symptoms and 12-month functional outcome of individuals at risk of psychosis.

Individuals seeking help from prodromal services may have been experiencing attenuated psychotic features and psychosocial impairments for a long period prior to referral. The effect of an extended duration of these untreated ;at risk' symptoms on patients' long-term functional outcome was assessed in a 12-month longitudinal observational study (n=49). A longer duration of untreated ;at risk' symptoms was correlated with a reduced improvement in Global Assessment of Functioning scores after 12 months (beta=-0.375, P=0.008). This effect was independent of age and gender and may have implications for the improvement of treatment strategies in pre-psychotic phases.

Economic impact of early intervention in people at high risk of psychosis.

BACKGROUND: Despite the increasing development of early intervention services for psychosis, little is known about their cost-effectiveness. We assessed the cost-effectiveness of Outreach and Support in South London (OASIS), a service for people with an at-risk mental state (ARMS) for psychosis. METHOD: The costs of OASIS compared to care as usual (CAU) were entered in a decision model and examined for 12- and 24-month periods, using the duration of untreated psychosis (DUP) and rate of transition to psychosis as key parameters. The costs were calculated on the basis of services used following referral and the impact on employment. Sensitivity analysis was used to test the robustness of all the assumptions made in the model. RESULTS: Over the initial 12 months from presentation, the costs of the OASIS intervention were pound1872 higher than CAU. However, after 24 months they were pound961 less than CAU. CONCLUSIONS: This model suggests that services that permit early detection of people at high risk of psychosis may be cost saving.

Interpersonal sensitivity in those at clinical high risk for psychosis mediates the association between childhood bullying victimisation and paranoid ideation: A virtual reality study.

BACKGROUND: Experience of bullying victimisation in childhood and heightened interpersonal sensitivity have been independently linked to the clinical high risk for psychosis. AIM: To examine the potential mediating effect of interpersonal sensitivity in explaining the link between childhood bullying victimisation and real-time paranoid ideation in adult participants at clinical high risk for psychosis. METHOD: In a cross-sectional study data were collected for 64 individuals at clinical high risk for psychosis. Measures included history of bullying victimisation, interpersonal sensitivity and state paranoid ideation following exposure to a social virtual reality environment. The virtual reality scenario was a London Underground journey. RESULTS: Path analysis indicated that interpersonal sensitivity fully explained the significant association between severe bullying victimisation in childhood and paranoid ideation in the clinical-high risk group. Based on AIC criteria the best model selected was the full mediation model: severe bullying→interpersonal sensitivity→state paranoid ideation. The results suggest that severity of bullying is more important than frequency of bullying in explaining state paranoid ideation. CONCLUSIONS: The significant role played by interpersonal sensitivity in the association between being bullied in childhood and paranoid ideation in the clinical high risk group suggests that this could become a target for intervention.