Cannabis use is a global public health issue associated with increased risks of developing mental health disorders, especially in young people. We aimed to investigate the relationships between cannabis exposure and risks of receiving mental illness diagnoses or treatment as outcomes.

A population based, retrospective, open cohort study using patients recorded in ‘IQVIA medical research data’, a UK primary care database. Read codes were used to confirm patients with recorded exposure to cannabis use who were matched up to two unexposed patients. We examined the risk of developing three categories of mental ill health: depression, anxiety or serious mental illness (SMI).

At study entry, the exposed cohort had an increased likelihood of having experienced mental ill health [odds ratio (OR) 4.13; 95% confidence interval (CI) 3.99–4.27] and mental ill health-related prescription (OR 2.95; 95% CI 2.86–3.05) compared to the unexposed group. During the study period we found that exposure to cannabis was associated with an increased risk of developing any mental disorder [adjusted hazard ratio (aHR) 2.73; 95% CI 2.59–2.88], also noted when examining by subtype of disorder: anxiety (aHR 2.46; 95% CI 2.29–2.64), depression (aHR 2.34; 95% CI 2.20–2.49) and SMI (aHR 6.41; 95% CI 5.42–7.57). These results remained robust in sensitivity analyses.

These findings point to the potential need for a public health approach to the management of people misusing cannabis. However, there is a gross under-recording of cannabis use in GP records, as seen by the prevalence of recorded cannabis exposure substantially lower than self-reported survey records.

While recent research points to the potential benefits of clinical intervention before the first episode of psychosis, the logistical feasibility of this is unclear.

To assess the feasibility of providing a clinical service for people with prodromal symptoms in an inner city area where engagement with mental health services is generally poor.

Following a period of liaison with local agencies to promote the service, referrals were assessed and managed in a primary care setting. Activity of the service was audited over 30 months.

People with prodromal symptoms were referred by a range of community agencies and seen at their local primary care physician practice. Over 30 months, 180 clients were referred; 58 (32.2%) met criteria for an at risk mental state, most of whom (67.2%) had attenuated psychotic symptoms. Almost 30% were excluded due to current or previous psychotic illness, of which two-thirds were in the first episode of psychosis. The socio-demographic composition of the 'at risk' group reflected that of the local population, with an over-representation of clients from an ethnic minority. Over 90% of suitable clients remained engaged with the service after 1 year.

It is feasible to provide a clinical service for people with prodromal symptoms in a deprived inner city area with a large ethnic minority population.

In dimensional understanding of psychosis, auditory verbal hallucinations (AVH) are unitary phenomena present on a continuum from non-clinical voice hearing to severe mental illness. There is mixed evidence for this approach and a relative absence of research into subjective experience of AVH in early psychosis.

To conduct primary research into the nature of subjective experience of AVH in first-episode psychosis.

A phenomenological study using diary and photo-elicitation qualitative techniques investigating the subjective experience of AVH in 25 young people with first-episode psychosis.

AVH are characterised by: (a) entity, as though from a living being with complex social interchange; and (b) control, exerting authority with ability to influence. AVH are also received with passivity, often accompanied by sensation in other modalities.

A modern detailed phenomenological investigation, without presupposition, gives results that echo known descriptive psychopathology. However, novel findings also emerge that may be features of AVH in psychosis not currently captured with standardised measures.

1. • Consider a spectrum of psychosis rather than a dichotomous concept of the disease (present/absent)

2. • Understand that, by preventing bullying, it may also be possible to prevent the development of psychotic symptoms

3. • Reflect that psychotherapy helps to integrate past stressful experiences with current symptoms, providing an alternative interpretation of them

It is unknown whether prodromal services improve outcomes in those who go on to develop psychosis, and whether these patients are demographically different from the overall first-episode population.

To compare sociodemographic features, duration of untreated psychosis, hospital admission and frequency of compulsory treatment in the first year after the onset of psychosis in patients who present to prodromal services with patients who did not present to services until the first episode of psychosis.

We compared two groups of patients with first-episode psychosis: one who made transition after presenting in the prodromal phase and the other who had presented with a first episode.

The patients who had presented before the first episode were more likely to be employed and less likely to belong to an ethnic minority group. They had a shorter duration of untreated psychosis, and were less likely to have been admitted to hospital and to have required compulsory treatment.

Patients who develop psychosis after being engaged in the prodromal phase have a better short-term clinical outcome than patients who do not present until the first episode. Patients who present during first episodes may be more likely to have sociodemographic features associated with relatively poor outcomes.

People with prodromal symptoms have a very high risk of developing psychosis.

To use functional magnetic resonance imaging to examine the neurocognitive basis of this vulnerability.

Cross-sectional comparison of regional activation in individuals with an ‘at-risk mental state’ (at-risk group: n=17), patients with first-episode schizophreniform psychosis (psychosis group: n=10) and healthy volunteers (controls: n=15) during an overt verbal fluency task and an N-back working memory task.

A similar pattern of between-group differences in activation was evident across both tasks. Activation in the at-risk group was intermediate relative to that in controls and the psychosis group in the inferior frontal and anterior cingulate cortex during the verbal fluency task and in the inferior frontal, dorsolateral prefrontal and parietal cortex during the N-back task.

The at-risk mental state is associated with abnormalities of regional brain function that are qualitatively similar to, but less severe than, those in patients who have recently presented with psychosis.

Virtual reality provides a means of studying paranoid thinking in controlled laboratory conditions. However, this method has not been used with a clinical group

To establish the feasibility and safety of using virtual reality methodology in people with an at-risk mental state and to investigate the applicability of a cognitive model of paranoia to this group

Twenty-one participants with an at-risk mental state were assessed before and after entering a virtual reality environment depicting the inside of an underground train

Virtual reality did not raise levels of distress at the time of testing or cause adverse experiences over the subsequent week. Individuals attributed mental states to virtual reality characters including hostile intent. Persecutory ideation in virtual reality was predicted by higher levels of trait paranoia, anxiety, stress, immersion in virtual reality, perseveration and interpersonal sensitivity

Virtual reality is an acceptable experimental technique for use with individuals with at-risk mental states. Paranoia in virtual reality was understandable in terms of the cognitive model of persecutory delusions

Aunque la investigatión recieñte senala los beneficios potenciales de la interventión clínica antes del primer episodio de psicosis, la viabilidad logística de esto no esta clara.

Evaluar la viabilidad de proporcionar un servicio clínico para personas con síntomas prodrómicos en un área urbana deprimida donde el compromiso con los servicios de salud mental es malo por lo general.

Después de un periodo de enlace con agencias locales para promover el servicio, se evaluó y trató las derivaciones en un entomo de atención primaria. La actividad del servicio se auditó durante 30 meses.

Diversas agencias comunitarias derivaron a las personas con síntomas prodrómicos. Se vio a estas personas en la consulta de su médico de atención primaria local. Durante 30 meses, derivaron a 180 clientes; 50 (32,%) cumplían los criterios para estado mental de riesgo, teniendo la mayoría de ellos (67,2%) síntomas psicóticos atenuados. Se excluyó casi al 30% debido a enfermedad psicótica actual o anterior; dos tercios de ellos estaban en el primer episodio de psicosis. La compositión sociodemográfica del grupo “en situation de riesgo” reflejaba la de la población local, con una sobre-representación de clientes de una minoría étnica. Más del 90% de los clients apropiados mantenía el compromiso con el servicio después de 1 año.

Es posible proporcionar un servicio clínico para personas con síntomas pródromicos en un área urbana deprimida deficitaria con una gran población de minoría ertnica.