BACKGROUND: Few studies have examined samples of people with cannabis-induced psychotic symptoms. AIMS: To establish whether cannabis-induced psychotic disorders are followed by development of persistent psychotic conditions, and the timing of their onset. METHOD: Data on patients treated for cannabis-induced psychotic symptoms between 1994 and 1999 were extracted from the Danish Psychiatric Central Register. Those previously treated for any psychotic symptoms were excluded. The remaining 535 patients were followed for at least 3 years. In a separate analysis, the sample was compared with people referred for schizophrenia-spectrum disorders for the first time, but who had no history of cannabis-induced psychosis. RESULTS: Schizophrenia-spectrum disorders were diagnosed in 44.5% of the sample. New psychotic episodes of any type were diagnosed in 77.2%. Male gender and young age were associated with increased risk. Development of schizophrenia-spectrum disorders was often delayed, and 47.1% of patients received a diagnosis more than a year after seeking treatment for a cannabis-induced psychosis. The patients developed schizophrenia at an earlier age than people in the comparison group (males, 24.6 v. 30.7 years, females, 28.9 v. 33.1 years). CONCLUSIONS: Cannabis-induced psychotic disorders are of great clinical and prognostic importance.
Ethnic minority status and childhood trauma are established risk factors for psychotic disorders. Both are found to be associated with increased level of positive symptoms, in particular auditory hallucinations. Our main aim was to investigate the experience and effect of childhood trauma in patients with psychosis from ethnic minorities, hypothesizing that they would report more childhood trauma than the majority and that this would be associated with more current and lifetime hallucinations.
In this cross-sectional study we included 454 patients with a SCID-I DSM-IV diagnosis of non-affective or affective psychotic disorder. Current hallucinations were measured with the Positive and Negative Syndrome Scale (P3; Hallucinatory Behaviour). Lifetime hallucinations were assessed with the SCID-I items: auditory hallucinations, voices commenting and two or more voices conversing. Childhood trauma was assessed with the Childhood Trauma Questionnaire, self-report version.
Patients from ethnic minority groups (n = 69) reported significantly more childhood trauma, specifically physical abuse/neglect, and sexual abuse. They had significantly more current hallucinatory behaviour and lifetime symptoms of hearing two or more voices conversing. Regression analyses revealed that the presence of childhood trauma mediated the association between ethnic minorities and hallucinations.
More childhood trauma in ethnic minorities with psychosis may partially explain findings of more positive symptoms, especially hallucinations, in this group. The association between childhood trauma and these first-rank symptoms may in part explain this group's higher risk of being diagnosed with a schizophrenia-spectrum diagnosis. The findings show the importance of childhood trauma in symptom development in psychosis.
Over a five-year period of registration in the county of S?r-Tr?ndelag we studied whether the frequency of consulting for one of three major psychiatric diagnostic groups (psychosis, neurosis, or "other") depended on the type of municipality (rural, coastal, urban) where the patient was resident. Diagnoses were based on consultations with a staff member of the regional outpatient psychiatric clinic, and the underlying population was described in the National Census, 1980. The results showed that, in general, urban residents sought help more frequently from the psychiatric outpatient clinic than rural residents did, (relative risk = 1.6, 95% confidence interval 1.4 to 1.8). The increased "risk" was attributed to a relatively larger number of neuroses and "other" diagnoses in the urban areas. The risk of consulting for psychosis was higher among coastal residents (relative risk = 1.8, 95% confidence interval 1.4 to 2.3) than among rural residents, was particularly evident among coastal residents between 16 and 39 years of age (relative risk = 4.1, 95% confidence interval 2.1 to 8.5), and was equally strong for men as for women. This study confirms that, in general, the risk of seeking outpatient psychiatric treatment is higher among urban than among rural and coastal residents. The apparently higher frequency of requests to the outpatient clinic for help for psychosis among coastal residents should be balanced against the tendency for city residents with psychosis to be admitted directly to the psychiatric hospital.
This study aimed to investigate the validity of disintegrative psychosis (DP) as defined in the ICD-9. The history of epilepsy in 13 subjects with DP was compared with that of 39 subjects with infantile autism (IA) who were matched for sex, age, IQ, and socioeconomic status (SES). The average follow-up time was 22 and 23 years (range 11 to 33 years). A significant difference was found between the DP and IA groups in terms of incidence of epilepsy, 77% versus 33% respectively. The peak period of onset of epilepsy occurred before puberty in both groups. Different types of epilepsy were seen, but the psychomotor variant accounted for 50% in the DP group, while 46% of the IA group had the psychomotor and 62% had the grand mal variant. The types are not mutually exclusive. Individuals without epilepsy had significantly higher IQ scores than those with epilepsy, but only within the IA group. The increased risk of developing epilepsy in the DP group is most likely a reflection of an underlying early brain pathology probably present in most individuals with DP. On the whole our findings can be seen as a contribution to the validation of DP as separate from IA, as these two conditions could be distinguished in terms of the way they develop with reference to epilepsy.
There has been increasing interest in the psychiatric literature on research and service delivery focused on first-episode psychosis (FEP), and accurate information on the incidence of FEP is crucial for the development of services targeting patients in the early stages of illness. We sought to obtain a population-based estimate of the incidence of first-episode schizophrenia-spectrum psychosis (SSP) among adolescents and young adults in Montreal.
Population-based administrative data from physician billings, hospitalizations, pharmacies, and public health clinics were used to estimate the incidence of first-episode SSP in Montreal. A 3-year period (2004-2006) was used to identify patients with SSP aged 14 to 25 years. We used a 4- to 6-year clearance period to remove patients with a history of any psychotic disorder or prescription for an antipsychotic.
We identified 456 patients with SSP, yielding a standardized annual incidence of 82.9 per 100 000 for males (95% CI 73.7 to 92.1), and 32.2 per 100 000 for females (95% CI 26.7 to 37.8). Using ecologic indicators of material and social deprivation, we found a higher-incidence proportion of SSP among people living in the most deprived areas, relative to people living in the least deprived areas.
Clinical samples obtained from psychiatric services are unlikely to capture all treatment-seeking patients, and epidemiologic surveys have resource-intensive constraints, making this approach challenging for rare forms of psychopathology; therefore, population-based administrative data may be a useful tool for studying the frequency of psychotic disorders.
Previous studies have suggested that the risk of psychosis, especially affective psychosis, is greatly increased during the first 30 days following delivery. The aim of our study was to replicate these findings. Linking The Danish Medical Birth Register and The Danish Psychiatric Central Register from January Ist 1973 to December 31st 1993 has revealed 1253 admissions diagnosed as psychosis within 91 days after delivery. The admission rate following delivery was compared to the admission rate among non-puerperal women in the general, Danish female population. The relative risk of all admissions was only slightly increased, RR = 1.09 (CI, 1.03-1.16). The admission rate concerning first admissions was greatly increased, RR = 3.21 (CI, 2.96-3.49) whereas the admission rate concerning readmissions was reduced, RR = 0.66 (CI, 0.61-0.72. In conclusion, childbirth is a strong risk factor for first admission with psychosis, but the risk is less increased than previously assumed.
Self-reported psychosis-like experiences (PEs) may be common in patients with mood disorders, but their clinical correlates are not well known. We investigated their prevalence and relationships with self-reported symptoms of depression, mania, anxiety, borderline (BPD) and schizotypal (SPD) personality disorders among psychiatric patients with mood disorders.
The Community Assessment of Psychic Experiences (CAPE-42), Mood Disorder Questionnaire (MDQ), McLean Screening Instrument (MSI), The Beck Depressive Inventory (BDI), Overall Anxiety Severity and Impairment Scale (OASIS) and Schizotypal Personality Questionnaire-Brief form (SPQ-B) were filled in by patients with mood disorders (n=282) from specialized care. Correlation coefficients between total scores and individual items of CAPE-42 and BDI, SPQ-B, MSI and MDQ were estimated. Hierarchical multivariate regression analysis was conducted to examine factors influencing the frequency of self-reported PE.
PEs are common in patients with mood disorders. The "frequency of positive symptoms" score of CAPE-42 correlated strongly with total score of SPQ-B (rho=0.63; P
To review the North American literature with respect to the role of social factors in the etiology of psychosis, including schizophrenia.
Relevant publications were identified through a search of MEDLINE from 1966 to 2006. Identified studies and articles had to originate in Canada or the United States to be included in the review. Articles written prior to 1966 were identified by cross-referencing bibliographies and reference lists. Articles were considered relevant if they discussed ethnoracial or other social factors as being causal or contributing to the development of psychosis or schizophrenia.
The relation between the etiology of psychosis and such social factors as poverty, migration, and racial discrimination has been neglected in the North American psychiatric literature for the last 40 years. In Canada and the United States, there is a dearth of research on these issues: the study of social causes of psychosis has been replaced by a focus on the clinical encounter, in which clinician bias is presumed to be responsible for widespread misdiagnosis of psychosis in minority (mainly African-American) populations. The reasons for neglecting social causes of psychosis in the North American psychiatric literature are obscure but may have to do with the rise of genetic-biological paradigms in recent decades.
The neglect of social causes of psychosis in the North American psychiatric literature has been coincident with an increase in scholarly concern among European clinicians and researchers. Careful reading of the European literature may reveal helpful avenues for future investigation in the North American context. In addition, drawing on social science literature and methods may help to clarify mechanisms underlying poverty, migration, and racial discrimination that contribute to psychosis in vulnerable individuals and groups.
Comment In: Can J Psychiatry. 2008 Jan;53(1):74; author reply 7418286875
Comment In: Can J Psychiatry. 2007 May;52(5):275-617542377