The effects of coronavirus disease 2019 (COVID-19) on the population's mental health and well-being are likely to be profound and long lasting.

To investigate the trajectory of mental health and well-being during the first 6 weeks of lockdown in adults in the UK.

A quota survey design and a sampling frame that permitted recruitment of a national sample was employed. Findings for waves 1 (31 March to 9 April 2020), 2 (10 April to 27 April 2020) and 3 (28 April to 11 May 2020) are reported here. A range of mental health factors was assessed: pre-existing mental health problems, suicide attempts and self-harm, suicidal ideation, depression, anxiety, defeat, entrapment, mental well-being and loneliness.

A total of 3077 adults in the UK completed the survey at wave 1. Suicidal ideation increased over time. Symptoms of anxiety, and levels of defeat and entrapment decreased across waves whereas levels of depressive symptoms did not change significantly. Positive well-being also increased. Levels of loneliness did not change significantly over waves. Subgroup analyses showed that women, young people (18–29 years), those from more socially disadvantaged backgrounds and those with pre-existing mental health problems have worse mental health outcomes during the pandemic across most factors.

The mental health and well-being of the UK adult population appears to have been affected in the initial phase of the COVID-19 pandemic. The increasing rates of suicidal thoughts across waves, especially among young adults, are concerning.

Controversy remains as to whether cannabis acts as a causal risk factor for schizophrenia or other functional psychotic illnesses.

To examine critically the evidence that cannabis causes psychosis using established criteria of causality.

We identified five studies that included a well-defined sample drawn from population-based registers or cohorts and used prospective measures of cannabis use and adult psychosis.

On an individual level, cannabis use confers an overall twofold increase in the relative risk for later schizophrenia. At the population level, elimination of cannabis use would reduce the incidence of schizophrenia by approximately 8%, assuming a causal relationship. Cannabis use appears to be neither a sufficient nor a necessary cause for psychosis. It is a component cause, part of a complex constellation of factors leading to psychosis.

Cases of psychotic disorder could be prevented by discouraging cannabis use among vulnerable youths. Research is needed to understand the mechanisms by which cannabis causes psychosis.

This paper presents a structured review of the published information on the mortality of schizophrenia.

A meta-analysis of the literature.

Schizophrenia has a significantly increased mortality from natural and unnatural causes. Twenty-eight percent of the excess mortality is attributable to suicide and 12% to accidents. The rest of the excess mortality is from the same broad range of conditions which cause deaths in the general population. Further interpretation is hampered by confounding variables, wide confidence intervals and reservations about generalising from individual cohorts.

The available evidence suggests that schizophrenia is associated with a large increased mortality from suicide and a moderate increased mortality from natural causes. A number of possible interventions have been identified, but we do not yet have reliable means of detecting any changes in mortality which might result.

Specific cortico-striato-thalamic circuits are hypothesised to mediate the symptoms of obsessive–compulsive disorder (OCD), but structural neuroimaging studies have been inconsistent.

To conduct a meta-analysis of published and unpublished voxel-based morphometry studies in OCD.

Twelve data-sets comprising 401 people with OCD and 376 healthy controls met inclusion criteria. A new improved voxel-based meta-analytic method, signed differential mapping (SDM), was developed to examine regions of increased and decreased grey matter volume in the OCD group v. control group.

No between-group differences were found in global grey matter volumes. People with OCD had increased regional grey matter volumes in bilateral lenticular nuclei, extending to the caudate nuclei, as well as decreased volumes in bilateral dorsal medial frontal/anterior cingulate gyri. A descriptive analysis of quartiles, a sensitivity analysis as well as analyses of subgroups further confirmed these findings. Meta-regression analyses showed that studies that included individuals with more severe OCD were significantly more likely to report increased grey matter volumes in the basal ganglia. No effect of current antidepressant treatment was observed.

The results support a dorsal prefrontal–striatal model of the disorder and raise the question of whether functional alterations in other brain regions commonly associated with OCD, such as the orbitofrontal cortex, may reflect secondary compensatory strategies. Whether the reported differences between participants with OCD and controls precede the onset of the symptoms and whether they are specific to OCD remains to be established.

Recent reports estimate the prevalence of autism-spectrum conditions in the UK to be 1%.

To use different methods to estimate the prevalence of autism-spectrum conditions, including previously undiagnosed cases, in Cambridgeshire.

We carried out a survey of autism-spectrum conditions using the Special Educational Needs (SEN) register. A diagnosis survey was distributed to participating schools to be handed out to parents of all children aged 5–9 years. The mainstream primary school population was screened for unknown cases.

The prevalence estimates generated from the SEN register and diagnosis survey were 94 per 10 000 and 99 per 10 000 respectively. A total of 11 children received a research diagnosis of an autism-spectrum condition following screening and assessment. The ratio of known:unknown cases is about 3:2 (following statistical weighting procedures). Taken together, we estimate the prevalence to be 157 per 10 000, including previously undiagnosed cases.

This study has implications for planning diagnostic, social and health services.

Major depressive disorder (MDD) is a leading cause of disability worldwide.

To examine the: (a) 12-month prevalence of DSM-IV MDD; (b) proportion aware that they have a problem needing treatment and who want care; (c) proportion of the latter receiving treatment; and (d) proportion of such treatment meeting minimal standards.

Representative community household surveys from 21 countries as part of the World Health Organization World Mental Health Surveys.

Of 51 547 respondents, 4.6% met 12-month criteria for DSM-IV MDD and of these 56.7% reported needing treatment. Among those who recognised their need for treatment, most (71.1%) made at least one visit to a service provider. Among those who received treatment, only 41.0% received treatment that met minimal standards. This resulted in only 16.5% of all individuals with 12-month MDD receiving minimally adequate treatment.

Only a minority of participants with MDD received minimally adequate treatment: 1 in 5 people in high-income and 1 in 27 in low-/lower-middle-income countries. Scaling up care for MDD requires fundamental transformations in community education and outreach, supply of treatment and quality of services.

The relative efficacy of different psychological treatments for chronic post-traumatic stress disorder (PTSD) is unclear.

To determine the efficacy of specific psychological treatments for chronic PTSD.

In a systematic review of randomised controlled trials, eligible studies were assessed against methodological qualitycriteria and data were extracted and analysed.

Thirty-eight randomised controlled trials were included in the meta-analysis. Trauma-focused cognitive-behavioural therapy (TFCBT), eye movement desensitisation and reprocessing (EMDR), stress management and group cognitive-behavioural therapy improved PTSD symptoms more than waiting-list or usual care. There was inconclusive evidence regarding other therapies. There was no evidence of a difference in efficacy between TFCBT and EMDR butthere was some evidence that TFCBT and EMDR were superior to stress management and other therapies, and that stress management was superior to other therapies.

The first-line psychological treatment for PTSD should be trauma-focused (TFCBTor EMDR).

The Hospital Anxiety and Depression (HAD) rating scale is a commonly used questionnaire. Former studies have given inconsistent results as to the psychometric properties of the HAD scale.

To examine the psychometric properties of the HAD scale in a large population.

All inhabitants aged 20–89 years (n=92 100) were invited to take part in The Nord-Tr⊘ndelag Health Study, Norway. A total of 65 648 subjects participated, and only completed HAD scale forms (n=51 930) formed the basis for the psychometric examinations.

Principal component analysis extracted two factors in the HAD scale that accounted for 57% of the variance. The anxiety and depression sub-scales shared 30% of the variance. Both sub-scales were found to be internally consistent, with values of Cronbach's coefficient (a) being 0.80 and 0.76, respectively.

Based on data from a large population, the basic psychometric properties of the HAD scale as a self-rating instrument should be considered as quite good in terms of factor structure, intercorrelation, homogeneity and internal consistency.

Epidemiological data on personality disorders, comorbidity and associated use of services are essential for health service policy.

To measure the prevalence and correlates of personality disorder in a representative community sample.

The Structured Clinical Interview for DSM-IV Axis II disorders was used to measure personality disorder in 626 persons aged 16-74 years in households in England, Scotland and Wales, in atwo-phase survey.

The weighted prevalence of personality disorder was 4.4% (95% CI 2.9-6.7). Rates were highest among men, separated and unemployed participants in urban locations. High use of healthcare services was confounded by comorbid mental disorder and substance misuse. Cluster B disorders were associated with early institutional care and criminality.

Personality disorder is common in the community especially in urban areas. Services are normally restricted to symptomatic, help-seeking individuals, but a vulnerable group with cluster B disorders can be identified early are in care during childhood and enter the criminal justice system when young. This suggests the need for preventive interventions at the public mental health level.

Mortality has been suggested to be increased in autism spectrum disorder (ASD).

To examine both all-cause and cause-specific mortality in ASD, as well as investigate moderating role of gender and intellectual ability.

Odds ratios (ORs) were calculated for a population-based cohort of ASD probands (n = 27 122, diagnosed between 1987 and 2009) compared with gender-, age- and county of residence-matched controls (n = 2 672 185).

During the observed period, 24 358 (0.91%) individuals in the general population died, whereas the corresponding figure for individuals with ASD was 706 (2.60%; OR = 2.56; 95% CI 2.38–2.76). Cause-specific analyses showed elevated mortality in ASD for almost all analysed diagnostic categories. Mortality and patterns for cause-specific mortality were partly moderated by gender and general intellectual ability.

Premature mortality was markedly increased in ASD owing to a multitude of medical conditions.

An acceptable, standardised outcome measure to assess efficacy and effectiveness is needed across multiple disciplines offering psychological therapies.

To present psychometric data on reliability, validity and sensitivity to change for the CORE–OM (Clinical Outcomes in Routine Evaluation – Outcome Measure).

A 34-item self-report instrument was developed, with domains of subjective well-being, symptoms, function and risk. Analysis includes internal reliability, test–retest reliability, socio-demographic differences, exploratory principal-component analysis, correlations with other instruments, differences between clinical and non-clinical samples and assessment of change within a clinical group.

Internal and test–retest reliability were good (0.75–0.95), as was convergent validity with seven other instruments, with large differences between clinical and non-clinical samples and good sensitivity to change.

The CORE–OM is a reliable and valid instrument with good sensitivity to change. It is acceptable in a wide range of practice settings.

Studies of people with schizophrenia assessed using magnetic resonance imaging (MRI) usually include patients with first-episode and chronic disease, yet brain abnormalities may be limited to those with chronic schizophrenia.

To determine whether patients with a first episode of schizophrenia have characteristic brain abnormalities.

Systematic review and meta-analysis of 66 papers comparing brain volume in patients with a first psychotic episode with volume in healthy controls.

Atotal of 52 cross-sectional studies included 1424 patients with a first psychotic episode; 16 longitudinal studies included 465 such patients. Meta-analysis suggests that whole brain and hippocampal volume are reduced (both P < 0.0001) and that ventricular volume is increased (P < 0.0001) in these patients relative to healthy controls.

Average volumetric changes are close to the limit of detection by MRI methods. It remains to be determined whether schizophrenia is a neurodegenerative process that begins at about the time of symptom onset, or whether it is better characterised as a neurodevelopmental process that produces abnormal brain volumes at an early age.

It is unclear how many children and adolescents develop post-traumatic stress disorder (PTSD) after trauma.

To determine the incidence of PTSD in trauma-exposed children and adolescents as assessed with well-established diagnostic interviews and to examine potential moderators of the estimate.

A systematic literature search identified 72 peer-reviewed articles on 43 independent samples (n = 3563). Samples consisting only of participants seeking or receiving mental health treatment were excluded. Main analyses involved pooled incidence estimates and meta-analyses of variance.

The overall rate of PTSD was 15.9% (95% CI 11.5–21.5), which varied according to the type of trauma and gender. Least at risk were boys exposed to non-interpersonal trauma (8.4%, 95% CI 4.7–14.5), whereas girls exposed to interpersonal trauma showed the highest rate (32.9%, 95% CI 19.8–49.3). No significant difference was found for the choice of assessment interview or the informant of the assessment.

Research conducted with the best available assessment instruments shows that a significant minority of children and adolescents develop PTSD after trauma exposure, with those exposed to interpersonal trauma and girls at particular risk. The estimates provide a benchmark for DSM-5 and ICD-11.

Suicide risk is greatly increased in schizophrenia. Detection of those at risk is clinically important.

To identify risk factors for suicide in schizophrenia.

The international literature on case-control and cohort studies of patients with schizophrenia or related conditions in which suicide was reported as an outcome was systematically reviewed. Studies were identified through searching electronic databases and reference lists, and by consulting experts.

Twenty-nine eligible studies were identified. Factors with robust evidence of increased risk of suicide were previous depressive disorders (OR=3.03, 95% CI 2.06–4.46), previous suicide attempts (OR=4.09, 95% CI 2.79–6.01), drug misuse (OR=3.21, 95% CI 1.99–5.17), agitation or motor restlessness (OR=2.61, 95% CI 1.54–4.41), fear of mental disintegration (OR=12.1, 95% CI 1.89–81.3), poor adherence to treatment (OR=3.75, 95% CI 2.20–6.37) and recent loss (OR=4.03, 95% CI 1.37–11.8). Reduced risk was associated with hallucinations (OR=0.50, 95% CI 0.35–0.71).

Prevention of suicide in schizophrenia is likely to result from treatment of affective symptoms, improving adherence to treatment, and maintaining special vigilance in patients with risk factors, especially after losses.