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Background: Cannabis use has been identified as a potent predictor of the earlier onset of psychosis, but meta-analysis has not indicated that it has a clear effect in established psychosis. Aim: To assess the association between cannabis and outcomes, including whether change in cannabis use affects symptoms and functioning, in a large sample of people with established nonaffective psychosis and comorbid substance misuse. Methods: One hundred and sixty participants whose substance use included cannabis were compared with other substance users (n = 167) on baseline demographic, clinical, and substance use variables. The cannabis using subgroup was examined prospectively with repeated measures of substance use and psychopathology at baseline, 12 months, and 24 months. We used generalized estimating equation models to estimate the effects of cannabis dose on subsequent clinical outcomes and whether change in cannabis use was associated with change in outcomes. Results: Cannabis users showed cross-sectional differences from other substances users but not in terms of positive symptoms. Second, cannabis dose was not associated with subsequent severity of positive symptoms and change in cannabis dose did not predict change in positive symptom severity, even when patients became abstinent. However, greater cannabis exposure was associated with worse functioning, albeit with a small effect size. Conclusions: We did not find evidence of an association between cannabis dose and psychotic symptoms, although greater cannabis dose was associated with worse psychosocial functioning, albeit with small effect size. It would seem that within this population, not everyone will demonstrate durable symptomatic improvements from reducing cannabis.  相似文献   
994.

Background

The term psychosis refers to a combination of symptoms, without pointing to the origin of these symptoms. In a subset of psychotic patients, symptoms are attributable to an organic disease. It is important to identify these organic causes of psychosis early, as urgent treatment of the primary disease may be required. Some of these underlying organic disorders can be identified on magnetic resonance imaging (MRI) scans. Whether routine screening for all psychotic patients should therefore include MRI scans is still a matter of debate.

Methods

This study investigated the prevalence of clinically relevant abnormalities detected on MRI scans from psychotic patients and a matched control group. We could include MRI scans from 656 psychotic patients and 722 controls. The standard radiological reports of these scans were classified as normal, as a nonrelevant abnormality or as a clinically relevant brain abnormality by means of consensus, blind to diagnosis.

Results

A normal aspect of the brain was reported in 74.4% of the patients and in 73.4% of the controls. We found clinically relevant pathology in 11.1% of the patients and in 11.8% of the controls. None of the neuropathological findings observed in the patients was interpreted as a possible substrate for organic psychosis. Brain abnormalities that were classified as not clinically relevant were identified in 14.5% of the patients and in 14.8% of the controls.

Conclusions

This suggests that MRI brain scans are not an essential part of routine screening for psychotic patients.  相似文献   
995.
Striatal dysfunction is thought to be a fundamental element in schizophrenia. Striatal dopamine dysfunction impacts on reward processing and learning and is present even at rest. Here, we addressed the question whether and how spontaneous neuronal activity in the striatum is altered in schizophrenia. We therefore assessed intrinsic striatal activity and its relation with disorder states and symptom dimensions in patients with schizophrenia. We performed resting-state functional (rs-fMRI) and structural magnetic resonance imaging as well as psychometric assessment in 21 schizophrenic patients during psychosis. On average 9 months later, we acquired follow-up data during psychotic remission and with comparable levels of antipsychotic medication. Twenty-one age- and sex-matched healthy controls were included in the study. Independent component analysis of fMRI data yielded spatial maps and time-courses of coherent ongoing blood-oxygen-level-dependent signal fluctuations, which were used for group comparisons and correlation analyses with scores of the positive and negative syndrome scale. During psychosis, coherent intrinsic activity of the striatum was increased in the dorsal part and correlated with positive symptoms such as delusion and hallucination. In psychotic remission of the same patients, activity of the ventral striatum was increased and correlated with negative symptoms such as emotional withdrawal and blunted affect. Results were controlled for volumetric and medication effects. These data provide first evidence that in schizophrenia intrinsic activity is changed in the striatum and corresponds to disorder states and symptom dimensions.  相似文献   
996.
Among adolescents referred between 1984 and 1989 to an outpatient clinic and followed up 6 years, 50 suicidal females were compared with 72 non-suicidal females, as well as with 37 suicidal surviving males, in terms of individual and treatment-related factors. Referral by health care professional, a history of previous inpatient care and mood disorders were more common among the suicidal females compared with the non-suicidal females. The proportion of those who had attempted suicide was higher among suicidal females than among suicidal surviving males (72% vs. 51%). Severe psychosocial impairment, psychotropic medication and a recommendation for inpatient treatment characterized both suicidal females and males. Psychosocial treatment modalities meeting the specific needs of mood-disordered adolescent female suicidal outpatients need to be developed.  相似文献   
997.
The effectiveness of a novel 7-month psychosocial treatment designed to prevent the second episode of psychosis was evaluated in a randomized controlled trial at 2 specialist first-episode psychosis (FEP) programs. An individual and family cognitive behavior therapy for relapse prevention was compared with specialist FEP care. Forty-one FEP patients were randomized to the relapse prevention therapy (RPT) and 40 to specialist FEP care. Participants were assessed on an array of measures at baseline, 7- (end of therapy), 12-, 18-, 24-, and 30-month follow-up. At 12-month follow-up, the relapse rate was significantly lower in the therapy condition compared with specialized treatment alone (P = .039), and time to relapse was significantly delayed for those in the relapse therapy condition (P = .038); however, such differences were not maintained. Unexpectedly, psychosocial functioning deteriorated over time in the experimental but not in the control group; these differences were no longer statistically significant when between-group differences in medication adherence were included in the model. Further research is required to ascertain if the initial treatment effect of the RPT can be sustained. Further research is needed to investigate if medication adherence contributes to negative outcomes in functioning in FEP patients who have reached remission, or, alternatively, if a component of RPT is detrimental.  相似文献   
998.
Although functional capacity is typically diminished, there is substantial heterogeneity in functional outcomes in schizophrenia. Motivational factors likely play a significant role in bridging the capacity-to-functioning gap. Self-efficacy theory suggests that although some individuals may have the capacity to perform functional behaviors, they may or may not have confidence they can successfully perform these behaviors in real-world settings. We hypothesized that the relationship between functional capacity and real-world functioning would be moderated by the individual’s self-efficacy in a sample of 97 middle-aged and older adults with schizophrenia (mean age = 50.9 ± 6.5 years). Functional capacity was measured using the Brief UCSD Performance-based Skills Assessment (UPSA-B), self-efficacy with the Revised Self-Efficacy Scale, and Daily Functioning via the Specific Level of Functioning (SLOF) scale and self-report measures. Results indicated that when self-efficacy was low, the relationship between UPSA-B and SLOF scores was not significant (P = .727). However, when self efficacy was high, UPSA-B scores were significantly related to SLOF scores (P = .020). Similar results were observed for self-reported social and work functioning. These results suggest that motivational processes (ie, self-efficacy) may aid in understanding why some individuals have the capacity to function well but do not translate this capacity into real-world functioning. Furthermore, while improvement in capacity may be necessary for improved functioning in this population, it may not be sufficient when motivation is absent.  相似文献   
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Background22q11.2 deletion syndrome (22q11DS) associates with schizophrenia spectrum disorders (SSDs), autism spectrum disorders (ASDs), and other psychiatric disorders, but co-occurrence of diagnoses are not well described.MethodsWe evaluated the co-occurrence of SSDs, ASDs and other axis I psychiatric diagnoses in 31 adolescents and adults with 22q11DS, assessing ASDs using either stringent Collaborative Program for Excellence in Autism (ASD-CPEA) criteria, or less stringent DSM-IV criteria alone (ASD-DSM-IV).ResultsTen (32%) individuals met criteria for an SSD, five (16%) for ASD-CPEA, and five others (16%) for ASD-DSM-IV. Of those with ASD-CPEA, one (20%) met SSD criteria. Of those with ASD-DSM-IV, four (80%) met SSD criteria. Depressive disorders (8 individuals; 26%) and anxiety disorders (7; 23%) sometimes co-occurred with SSDs and ASDs. SSDs, ASDs, and anxiety occurred predominantly among males and depression predominantly among females.ConclusionsIndividuals with 22q11DS can manifest SSDs in the presence or absence of ASDs and other axis I diagnoses. The results suggest that standard clinical care should include childhood screening for ASDs, and later periodic screening for all axis I diagnoses.  相似文献   
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