A wide range of cognitive deficits have been demonstrated in schizophrenia, but their longitudinal course remains unclear.

To bring together all the available information from longitudinal studies of cognitive performance in people with schizophrenia.

We carried out a meta-analysis of 53 studies. Unlike previous reviewers, we included all studies (regardless of the type of medication), analysed each variable separately and compared results with data from controls.

Participants with schizophrenia showed a significant improvement in most cognitive tasks. The available data for controls showed, with one exception (the Stroop test), a similar or greater improvement. Performance in semantic verbal fluency remained stable in both individuals with schizophrenia and controls.

Participants with schizophrenia displayed improvement in most cognitive tasks, but practice was more likely than cognitive remediation to account for most of the improvements observed. Semantic verbal fluency may be the best candidate cognitive endophenotype.

The increased prevalence of diabetes in schizophrenia is partly attributed to antipsychotic treatment, in particular second-generation antipsychotics, but the evidence has not been systematically reviewed.

Systematic review and meta-analysis comparing diabetes risk for different antipsychotics in people with schizophrenia.

We searched MEDLINE, PsycINFO, EMBASE, International Pharmaceutical Abstracts, CINAHL and Web of Knowledge until September 2006. Studies were eligible for inclusion if the design was cross-sectional, case-control, cohort or a controlled trial in individuals with schizophrenia or related psychotic disorders, where second-generation antipsychotics (defined as clozapine, olanzapine, risperidone and quetiapine) were compared with first-generation antipsychotics and diabetes was an outcome. Data were pooled using random effects inverse variance weighted meta-analysis.

Of the studies that met the inclusion criteria (n=14), 11 had sufficient data to include in the meta-analysis. Four of these were retrospective cohort studies. The relative risk of diabetes in patients with schizophrenia prescribed one of the second-generation v. first-generation antipsychotics was 1.32 (95% CI 1.15-1.51). There were insufficient data to include aripiprazole, ziprasidone and amisulpride in this analysis.

There is tentative evidence that the second-generation antipsychotics included in this study are associated with a small increased risk for diabetes compared with firstgeneration antipsychotics in people with schizophrenia. Methodological limitations were found in most studies, leading to heterogeneity and difficulty interpreting data. Regardless of type of antipsychotic, screening for diabetes in all people with schizophrenia should be routine.

Many theorists posit that childhood sexual abuse has a central role in the aetiology of self-injurious behaviour. Studies that report statistically significant associations between a history of such abuse and self-injury are cited to support this view.

A meta-analysis was conducted to determine systematically the magnitude of the association between childhood sexual abuse and self-injurious behaviour.

Forty-five analyses of the association were identified. Effect sizes were converted to a standard metric and aggregated.

The relationship between childhood sexual abuse and self-injurious behaviour is relatively small (mean weighted aggregate ϕ=0.23). This figure may be inflated owing to publication bias. In studies that statistically controlled for psychiatric risk factors, childhood sexual abuse explained little or no unique variance in self-injurious behaviour.

Theories that childhood sexual abuse has a central or causal role in the development of self-injurious behaviour are not supported by the available empirical evidence. Instead, it appears that the two are modestly related because they are correlated with the same psychiatric risk factors.

Increased semantic priming is an influential theory of thought disorder in schizophrenia. However, studies to date have had conflicting findings.

To investigate semantic memory in patients with schizophrenia with and without thought disorder.

Data were pooled from 36 studies comparing patients with schizophrenia and normal controls in semantic priming tasks. Data from 18 studies comparing patients with thought disorder with normal controls, and 13 studies comparing patients with and without thought disorder were also pooled.

There was no support for altered semantic priming in schizophrenia as a whole. Increased semantic priming in patients with thought disorder was supported, but this was significant only in comparison with normal controls and not in comparison with patients without thought disorder. Stimulus onset asynchrony (SOA) and general slowing of reaction time moderated the effect size for priming in patients with thought disorder.

Meta-analysis provides qualified support for increased semantic priming as a psychological abnormality underlying thought disorder. However, the possibility that the effect is an artefact of general slowing of reaction time in schizophrenia has not been excluded.

Family intervention reduces relapse rates in psychosis. Cognitive-behavioural therapy (CBT) improves positive symptoms but effects on relapse rates are not established.

To test the effectiveness of CBT and family intervention in reducing relapse, and in improving symptoms and functioning in patients who had recently relapsed with non-affective psychosis.

A multicentre randomised controlled trial (ISRCTN83557988) with two pathways: those without carers were allocated to treatment as usual or CBT plus treatment as usual, those with carers to treatment as usual, CBT plus treatment as usual or family intervention plus treatment as usual. The CBT and family intervention were focused on relapse prevention for 20 sessions over 9 months.

A total of 301 patients and 83 carers participated. Primary outcome data were available on 96% of the total sample. The CBT and family intervention had no effects on rates of remission and relapse or on days in hospital at 12 or 24 months. For secondary outcomes, CBT showed a beneficial effect on depression at 24 months and there were no effects for family intervention. In people with carers, CBT significantly improved delusional distress and social functioning. Therapy did not change key psychological processes.

Generic CBT for psychosis is not indicated for routine relapse prevention in people recovering from a recent relapse of psychosis and should currently be reserved for those with distressing medication-unresponsive positive symptoms. Any CBT targeted at this acute population requires development. The lack of effect of family intervention on relapse may be attributable to the low overall relapse rate in those with carers.

The public health significance of mixed anxiety–depressive disorder (MADD) and the distinctiveness of its phenomenology have yet to be established.

To determine the public health significance of MADD, and to compare its phenomenology with ICD-10 anxiety, depressive, and comorbid anxiety and depressive disorders.

Weighted analysis of data from the Great Britain National Psychiatric Morbidity survey was conducted with a representative household sample of 8580 persons aged 16–74 years.

The 1-month prevalence of MADD was 8.8%. A fifth of all days off work in Britain occurred in this group. The symptom profile of MADD was similar to ‘pure’ ICD-10 anxiety and depression, but with a lower overall symptom count. The disorder was associated with significant impairment of health-related quality of life. Differences in health-related quality of life measures between diagnostic groups were accounted for by overall symptom severity, which remained strongly associated with health-related quality of life measures after adjusting for diagnostic group. The finding that half of the anxiety, depression and MADD cases and a third of the comorbid depression and anxiety cases grouped into a single latent class challenges the notion of these conditions as having distinct phenomenologies. Mixed presentations may be the norm in the population.

The data support the pathological significance of MADD in its negative impact upon population health. Dimensional approaches to classification may provide a more parsimonious description of anxiety and depressive disorders compared with categorical approaches.

Obesity and metabolic syndrome are significant problems for patients taking antipsychotic drugs. Evidence is emerging of genetic risk factors.

To investigate the influence of two candidate genes, smoking and drug treatment on obesity and metabolic syndrome in patients with schizophrenia.

Patients (n=134) were assessed for measures of obesity, other factors contributing to metabolic syndrome, and two genetic polymorphisms(5-HT2C receptor −759C/T and leptin −2548A/G).

Neither genotype nor smoking was significantly associated with measures of obesity. However, both leptin genotype and smoking were significantly associated with metabolic syndrome. Significant interaction occurred between the genetic polymorphisms for effects on obesity, whereby a genotype combination increased risk. Drug treatment showed significant effects on measures of obesity and triglyceride concentrations; risperidone was associated with lower values than olanzapine or clozapine.

The findings suggest interacting genetic risk factors and smoking influence development of metabolic syndrome in patients on antipsychotic drugs.

Depression may increase the risk of mortality among certain subgroups of older people, but the part played by antidepressants in this association has not been thoroughly explored.

To identify the characteristics of older populations who are most at risk of dying, as a function of depressive symptoms, gender and antidepressant use.

Adjusted Cox proportional hazards models were used to determine the association between depression and/or antidepressant use and 4-year survival of 7363 community-dwelling elderly people. Major depressive disorder was evaluated using a standardised psychiatric examination based on DSM-IV criteria and depressive symptoms were assessed using the Center for Epidemiological Studies Depression scale.

Depressed men using antidepressants had the greatest risk of dying, with increasing depression severity corresponding to a higher hazard risk. Among women, only severe depression in the absence of treatment was significantly associated with mortality.

The association between depression and mortality is gender-dependent and varies according to symptom load and antidepressant use.

Suicide is a leading cause of death worldwide; however, the prevalence and risk factors for the immediate precursors to suicide – suicidal ideation, plans and attempts – are not well-known, especially in low- and middle-income countries.

To report on the prevalence and risk factors for suicidal behaviours across 17 countries.

A total of 84 850 adults were interviewed regarding suicidal behaviours and socio-demographic and psychiatric risk factors.

The cross-national lifetime prevalence of suicidal ideation, plans, and attempts is 9.2% (s.e.=0.1), 3.1% (s.e.=0.1), and 2.7% (s.e.=0.1). Across all countries, 60% of transitions from ideation to plan and attempt occur within the first year after ideation onset. Consistent cross-national risk factors included being female, younger, less educated, unmarried and having a mental disorder. Interestingly, the strongest diagnostic risk factors were mood disorders in high-income countries but impulse control disorders in low- and middle-income countries.

There is cross-national variability in the prevalence of suicidal behaviours, but strong consistency in the characteristics and risk factors for these behaviours. These findings have significant implications for the prediction and prevention of suicidal behaviours.

Judging whether we can trust other people is central to social interaction, despite being error-prone. A fear of others can be instilled by the contemporary political and social climate. Unfounded mistrust is called paranoia, and in severe forms is a central symptom of schizophrenia.

To demonstrate that individuals without severe mental illness in the general population experience unfounded paranoid thoughts, and to determine factors predictive of paranoia using the first laboratory method of capturing the experience.

Two hundred members of the general public were comprehensively assessed, and then entered a virtual reality train ride populated by neutral characters. Ordinal logistic regressions (controlling for age, gender, ethnicity, education, intellectual functioning, socio-economic status, train use, playing of computer games) were used to determine predictors of paranoia.

The majority agreed that the characters were neutral, or even thought they were friendly. However, a substantial minority reported paranoid concerns. Paranoia was strongly predicted by anxiety, worry, perceptual anomalies and cognitive inflexibility.

This is the most unambiguous demonstration of paranoid ideation in the general public so far. Paranoia can be understood in terms of cognitive factors. The use of virtual reality should lead to rapid advances in the understanding of paranoia.

The shape of the corpus callosum may differ in schizophrenia, although no study has compared first-episode with established illness.

To investigate the size and shape of the corpus callosum in a large sample of people with first-episode and established schizophrenia.

Callosal size and shape were determined using highresolution magnetic resonance imaging on 76 patients with first-episode schizophrenia-spectrum disorders, 86 patients with established schizophrenia and 55 healthy participants.

There were no significant differences in total area across groups. Reductions in callosal width were seen in the region of the anterior genu in first-episode disorder (P<0.005). Similar reductions were seen in the chronic schizophrenia group in the anterior genu, but also in the posterior genu and isthmus (P = 0.0005).

Reductions in anterior callosal regions connecting frontal cortex are present at the onset of schizophrenia, and in established illness are accompanied by changes in other regions of the callosum connecting cingulate, temporal and parietal cortices.

Lack of social interaction, which is characteristically seen in people with autistic-spectrum disorder, may be caused by malfunctioning of the frontostriatal reward systems. However, no reported in vivo brain imaging studies have investigated reward mechanisms in autistic-spectrum disorder.

To investigate functional brain activation during reward feedback in people with autistic-spectrum disorder and control individuals.

We used event-related functional magnetic resonance imaging to examine the neural substrates of monetary reward in individuals with autistic-spectrum disorder and matched controls.

When rewarded, individuals with autism compared with control individuals showed significantly greater brain activation in the left anterior cingulate gyrus. In addition, activation of this region was negatively correlated with social interaction as measured by the Autism Diagnostic Interview.

In people with autistic-spectrum disorder, achieving reward is associated with significant differences in the activation of areas known to be responsible for attention and arousal, and this may partially underpin some deficits in social behaviour.

The effects of in utero exposure to atypical antipsychotics on infant birth weight are unknown.

To determine whether atypical and typical antipsychotics differ in their effects on birth weight after maternal exposure during pregnancy.

Prospective data on gestational age and birth weight collected by the National Teratology Information Service for infants exposed to typical (n=45) and atypical (n=25) antipsychotics was compared with data for a reference group of infants (n=38).

Infants exposed to atypical antipsychotics had a significantly higher incidence of large for gestational age (LGA) than both comparison groups and a mean birth weight significantly heavier than those exposed to typical antipsychotics. In contrast those exposed to typical antipsychotics had a significantly lower mean birth weight and a higher incidence of small for gestational age infants than the reference group.

In utero exposure to atypical antipsychotic drugs may increase infant birth weight and risk of LGA.