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Background: There is considerable interest in cannabis use in psychosis. It has been suggested that the chronic psychosis associated with cannabis use, is symptomatically distinct from idiopathic schizophrenia. Several studies have reported differences in psychopathology and family history in people with schizophrenia according to whether or not they were cannabis users. We set out to test the hypotheses arising from these studies that cannabis use is associated with more bizarre behaviour, more thought disorder, fewer negative symptoms including blunted affect, more delusions of reference, more paranoid delusions and a stronger family history of schizophrenia. Method: We used a case register that contained 757 cases of first onset schizophrenia, 182 (24%) of whom had used cannabis in the year prior to first presentation, 552 (73%) had not and 3% had missing data. We completed the OPCRIT checklist on all patients and investigated differences in the proportion of people with distractibility, bizarre behaviour, positive formal thought disorder, delusions of reference, well organised delusions, any first rank symptom, persecutory delusions, abusive/accusatory hallucinations, blunted affect, negative thought disorder, any negative symptoms (catatonia, blunted affect, negative thought disorder, or deterioration), lack of insight, suicidal ideation and a positive family history of schizophrenia, using chi square tests. Logistic regression modelling was then used to determine whether prior cannabis use affected the presence of the characteristics after controlling for age, sex and ethnicity. Results: There was no statistically significant effect of cannabis use on the presence of any of the above. There remained however a non-significant trend towards more insight (OR 0.65 p=0.055 for “loss of insight”) and a finding of fewer abusive or accusatory hallucinations (OR 0.65 p=0.049) of borderline significance amongst the cannabis users. These were in the hypothesised direction. There was no evidence of fewer negative symptoms or greater family history amongst cannabis users. Conclusion: We found few appreciable differences in symptomatology between schizophrenic patients who were or were not cannabis users. There were no differences in the proportion of people with a positive family history of schizophrenia between cannabis users and non-users. This argues against a distinct schizophrenia-like psychosis caused by cannabis. © 2007 Elsevier B.V. All rights reserved.

Background: Much remains unknown about whether there are early risk factors for suicide in psychosis. Aim: The aim of the study was to determine whether there are any identifiable early symptom clusters, aetiological factors or illness course markers for suicide in first episode psychosis. Method: A total of 2132 patients with first episode psychosis presenting to secondary care services in London (1965-2004; n = 1474), Nottingham (1997-1999; n = 195) and Dumfries and Galloway (1979-1998; n = 463) were traced after up to 40 years (mean 13 years) following first presentation. Risk factors were identified from the Operational Checklist for Psychotic Disorders rated for the first year following presentation. Results: Overall, there were 51 suicides and 373 deaths from other causes. Male gender (RR 2.84, 95% Cl 1.20-6.69, p = 0.02) and a cumulative threshold effect of symptoms early in the illness (RR 6.81,95% Cl 2.33-19.85, p

Background: The long term risk of suicide following first onset of psychosis is unknown, because previous studies have (1) been based on prevalence cohorts, (2) been biased to more severely ill, hospitalised patients, (3) extrapolated from short follow–up times and (4) made a distinction between schizophrenia and other psychoses. Previous research has identified risk factors in the period leading up to suicide in psychotic illness, but little is known about whether factors identifiable early in the course of illness might be markers for later suicide. Objectives: (i) To determine the epidemiology of suicide and (ii) to investigate potential early risk factors for suicide in a clinically representative, retrospective inception cohort of n=2,723 first onset psychosis patients. Method: All 2,723 patients who presented for the first time to secondary care services with psychosis in three defined geographical catchment areas in London (1965-2004; n=2056), Nottingham (1997-1999; n=203) and Dumfries and Galloway (1979-1998; n=464) were traced after a mean follow-up period of 11.5 years and death certificates were obtained to identify deaths by suicide and open verdicts according to ICD-7-10. Potential early risk factors for suicide were identified from the Operational Checklist for Psychotic Disorders rated for the first year following presentation. Results: Overall there were 53 suicides and 391 deaths from other causes. Case fatality from suicide was considerably lower than expected from previous studies: 1.9% (53/2723); proportionate mortality was 11.9% (53/444). Although the rate of suicide was highest in the first year after presentation, risk persisted late into follow-up, with median time to suicide being 5.6 years. Suicide occurred approximately 12 times more than expected from the general population of England and Wales (SMR 11.65; 95%CI 8.7315.24), and 49 of the 53 suicides were excess deaths. Even a decade after first presentation, suicide risk remained almost 4 times higher than in the general population (SMR 3.92; 95%CI 2.22-6.89): a time when there may be less intense clinical monitoring of risk. Male gender (RR 2.84, 95% CI 1.206.69, p=0.02) and a cumulative threshold effect of symptoms early in the illness (RR 6.81, 95% CI 2.33-19.85, p