Disorganisation, thought disorder and socio-cognitive functioning in schizophrenia spectrum disorders.

BACKGROUND: Poor social cognition is prevalent in schizophrenia spectrum disorders. Some authors argue that these effects are symptom-specific and that socio-cognitive difficulties (e.g. theory of mind) are strongly associated with thought disorder and symptoms of disorganisation.AimsThe current review tests the strength of this association. METHOD: We meta-analysed studies published between 1980 and 2016 that tested the association between social cognition and these symptoms in schizophrenia spectrum disorders. RESULTS: Our search (PsycINFO, MEDLINE and Web of Science) identified 123 studies (N = 9107). Overall effect size as r = -0.313, indicating a moderate association between symptoms and social cognition. Subanalyses yielded a moderate association between symptoms and theory of mind (r = -0.349) and emotion recognition (r = -0.334), but smaller effect sizes for social perception (r = -0.188), emotion regulation (r = -0.169) and attributional biases (r = -0.143). CONCLUSIONS: The association is interpreted within models of communication that highlight the importance of mentalisation and processing of partner-specific cues in conversational alignment and grounding.Declaration of interestsNone.

Assessing Feasibility and Acceptability of Web-Based Enhanced Relapse Prevention for Bipolar Disorder (ERPonline): A Randomized Controlled Trial.

BACKGROUND: Interventions that teach people with bipolar disorder (BD) to recognize and respond to early warning signs (EWS) of relapse are recommended but implementation in clinical practice is poor. OBJECTIVES: The objective of this study was to test the feasibility and acceptability of a randomized controlled trial (RCT) to evaluate a Web-based enhanced relapse prevention intervention (ERPonline) and to report preliminary evidence of effectiveness. METHODS: A single-blind, parallel, primarily online RCT (n=96) over 48 weeks comparing ERPonline plus usual treatment with "waitlist (WL) control" plus usual treatment for people with BD recruited through National Health Services (NHSs), voluntary organizations, and media. Randomization was independent, minimized on number of previous episodes (<8, 8-20, 21+). Primary outcomes were recruitment and retention rates, levels of intervention use, adverse events, and participant feedback. Process and clinical outcomes were assessed by telephone and Web and compared using linear models with intention-to-treat analysis. RESULTS: A total of 280 people registered interest online, from which 96 met inclusion criteria, consented, and were randomized (49 to WL, 47 to ERPonline) over 17 months, with 80% retention in telephone and online follow-up at all time points, except at week 48 (76%). Acceptability was high for both ERPonline and trial methods. ERPonline cost approximately £19,340 to create, and £2176 per year to host and maintain the site. Qualitative data highlighted the importance of the relationship that the users have with Web-based interventions. Differences between the group means suggested that access to ERPonline was associated with: a more positive model of BD at 24 weeks (10.70, 95% CI 0.90 to 20.5) and 48 weeks (13.1, 95% CI 2.44 to 23.93); increased monitoring of EWS of depression at 48 weeks (-1.39, 95% CI -2.61 to -0.163) and of hypomania at 24 weeks (-1.72, 95% CI -2.98 to -0.47) and 48 weeks (-1.61, 95% CI -2.92 to -0.30), compared with WL. There was no evidence of impact of ERPonline on clinical outcomes or medication adherence, but relapse rates across both arms were low (15%) and the sample remained high functioning throughout. One person died by suicide before randomization and 5 people in ERPonline and 6 in WL reported ideas of suicide or self-harm. None were deemed study related by an independent Trial Steering Committee (TSC). CONCLUSIONS: ERPonline offers a cheap accessible option for people seeking ongoing support following successful treatment. However, given high functioning and low relapse rates in this study, testing clinical effectiveness for this population would require very large sample sizes. Building in human support to use ERPonline should be considered. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number (ISRCTN): 56908625; http://www.isrctn.com/ISRCTN56908625 (Archived by WebCite at http://www.webcitation.org/6of1ON2S0).

Backward bifurcation, equilibrium and stability phenomena in a three-stage extended BRSV epidemic model.

In this paper we consider the phenomenon of backward bifurcation in epidemic modelling illustrated by an extended model for Bovine Respiratory Syncytial Virus (BRSV) amongst cattle. In its simplest form, backward bifurcation in epidemic models usually implies the existence of two subcritical endemic equilibria for R(0) < 1, where R(0) is the basic reproductive number, and a unique supercritical endemic equilibrium for R(0) > 1. In our three-stage extended model we find that more complex bifurcation diagrams are possible. The paper starts with a review of some of the previous work on backward bifurcation then describes our three-stage model. We give equilibrium and stability results, and also provide some biological motivation for the model being studied. It is shown that backward bifurcation can occur in the three-stage model for small b, where b is the common per capita birth and death rate. We are able to classify the possible bifurcation diagrams. Some realistic numerical examples are discussed at the end of the paper, both for b small and for larger values of b.

Temporal and geographic patterns of stab injuries in young people: a retrospective cohort study from a UK major trauma centre.

OBJECTIVES: To describe the epidemiology of assaults resulting in stab injuries among young people. We hypothesised that there are specific patterns and risk factors for injury in different age groups. DESIGN: Eleven-year retrospective cohort study. SETTING: Urban major trauma centre in the UK. PARTICIPANTS: 1824 patients under the age of 25 years presenting to hospital after a stab injury resulting from assault. OUTCOMES: Incident timings and locations were obtained from ambulance service records and triangulated with prospectively collected demographic and injury characteristics recorded in our hospital trauma registry. We used geospatial mapping of individual incidents to investigate the relationships between demographic characteristics and incident timing and location. RESULTS: The majority of stabbings occurred in males from deprived communities, with a sharp increase in incidence between the ages of 14 and 18 years. With increasing age, injuries occurred progressively later in the day (r2=0.66, p<0.01) and were less frequent within 5 km of home (r2=0.59, p<0.01). Among children (age <16), a significant peak in injuries occurred between 16:00 and 18:00 hours, accounting for 22% (38/172) of injuries in this group compared with 11% (182/1652) of injuries in young adults. In children, stabbings occurred earlier on school days (hours from 08:00: 11.1 vs non-school day 13.7, p<0.01) and a greater proportion were within 5 km of home (90% vs non-school day 74%, p=0.02). Mapping individual incidents demonstrated that the spike in frequency in the late afternoon and early evening was attributable to incidents occurring on school days and close to home. CONCLUSIONS: Age, gender and deprivation status are potent influences on the risk of violent injury in young people. Stab injuries occur in characteristic temporal and geographical patterns according to age group, with the immediate after-school period associated with a spike in incident frequency in children. This represents an opportunity for targeted prevention strategies in this population.

Users' experiences of an online intervention for bipolar disorder: important lessons for design and evaluation.

BACKGROUND: The evidence base for digital interventions for physical and mental health, including severe and enduring mental health difficulties, is increasing. In a feasibility trial, web-based Enhanced Relapse Prevention (ERPonline) for bipolar disorder demonstrated high recruitment and retention rates. Relative to participants in the waitlist control group, those who received ERPonline showed increased monitoring for early warning signs of relapse and had developed more positive illness models. OBJECTIVE: To understand users' motivations and barriers for taking part in an online/telephone-based trial, and for engagement with ERPonline. METHODS: Participants from the trial who had been allocated to receive ERPonline were purposively sampled to participate in telephone-based, in-depth qualitative interviews about their experiences. Interviews (n=19) were analysed using framework analysis to identify themes relevant to study aims. FINDINGS: Participants took part due to the convenient, flexible and rewarding aspects of the trial design, as well as a desire to improve the mental health of themselves and others. Barriers included extensive assessments, practical difficulties and mood. ERPonline was was generally considered to be accessible, relevant and straightforward, but there were individual preferences regarding design, content and who it was for. Several participants reported positive changes, but there was a sense that digital interventions should not replace routine care. CONCLUSIONS: There are a number of barriers and facilitators to consider when evaluating and implementing digital interventions. Individual preferences and human contact were key factors for both trial design and engagement with an online intervention. CLINICAL IMPLICATIONS: Digital interventions should be co-produced, personalised, interactive and embedded as one component in a broader package of care. TRIAL REGISTRATION NUMBER: ISRCTN56908625; Post-results.

Gluteal compartment syndrome with severe rhabdomyolysis.

Gluteal compartment syndrome is a rare entity but a recognised complication of prolonged immobilisation. It can present as renal failure as a result of severe rhabdomyolysis and can lead to sepsis and death. We report a case of gluteal compartment syndrome in a 25-year-old man who was found unconscious following intoxication with alcohol and cocaine of an unknown duration. He presented with tense tight left buttock swelling, right thigh swelling, cold immobile extremeties and acute renal failure. Immediate left gluteal, thigh and calf fasciotomy resulting in an improvement of lower limb and renal function.

The probability of extinction in a bovine respiratory syncytial virus epidemic model.

Backward bifurcation is a relatively recent yet well-studied phenomenon associated with deterministic epidemic models. It allows for the presence of multiple subcritical endemic equilibria, and is generally found only in models possessing a reasonable degree of complexity. One particular aspect of backward bifurcation that appears to have been virtually overlooked in the literature is the potential influence its presence might have on the behaviour of any analogous stochastic model. Indeed, the primary aim of this paper is to investigate this possibility. Our approach is to compare the theoretical probabilities of extinction, calculated via a particular stochastic formulation of a deterministic model exhibiting backward bifurcation, with those obtained from a series of stochastic simulations. We have found some interesting links in the behaviour between the deterministic and stochastic models, and are able to offer plausible explanations for our observations.

Dynamic phenomena arising from an extended Core Group model.

In order to obtain a reasonably accurate model for the spread of a particular infectious disease through a population, it may be necessary for this model to possess some degree of structural complexity. Many such models have, in recent years, been found to exhibit a phenomenon known as backward bifurcation, which generally implies the existence of two subcritical endemic equilibria. It is often possible to refine these models yet further, and we investigate here the influence such a refinement may have on the dynamic behaviour of a system in the region of the parameter space near R(0)=1. We consider a natural extension to a so-called Core Group model for the spread of a sexually transmitted disease, arguing that this may in fact give rise to a more realistic model. From the deterministic viewpoint we study the possible shapes of the resulting bifurcation diagrams and the associated stability patterns. Stochastic versions of both the original and the extended models are also developed so that the probability of extinction and time to extinction may be examined, allowing us to gain further insights into the complex system dynamics near R(0)=1. A number of interesting phenomena are observed, for which heuristic explanations are provided.