A complex network perspective on clinical science

Contemporary classification systems for mental disorders assume that abnormal behaviors are expressions of latent disease entities. An alternative to the latent disease model is the complex network approach. Instead of assuming that symptoms arise from an underlying disease entity, the complex network approach holds that disorders exist as systems of interrelated elements of a network. This approach also provides a framework for the understanding of therapeutic change. Depending on the structure of the network, change can occur abruptly once the network reaches a critical threshold (the tipping point). Homogeneous and highly connected networks often recover more slowly from local perturbations when the network approaches the tipping point, potentially making it possible to predict treatment change, relapse, and recovery. In this article, we discuss the complex network approach as an alternative to the latent disease model and its implications for classification, therapy, relapse, and recovery.R34 MH086668 - NIMH NIH HHS; R01 AT007257 - NCCIH NIH HHS; R21 MH101567 - NIMH NIH HHS; R34 MH099311 - NIMH NIH HHS; R21 MH102646 - NIMH NIH HHS; K23 MH100259 - NIMH NIH HHS; R01 MH099021 - NIMH NIH HH

Why Psychiatrists Can’t Predict Mass Murderers

Psycholog

Risk Factors and Posttraumatic Stress Disorder: Are They Especially Predictive Following Exposure to Less Severe Stressors?

Background: The diagnosis of posttraumatic stress disorder (PTSD) requires exposure to a traumatic stressor, as defined by Criterion A in the DSM criteria for PTSD. Yet, over the course of successive revisions of the diagnostic manual, the range of qualifying stressors has expanded considerably (e.g., watching terrorist attacks on television). Moreover, stressors that fall short of qualifying for even an expanded Criterion A can produce apparent PTSD. Taken together, these findings imply that people who do satisfy symptomatic criteria for PTSD following exposure to less severe stressors carry a heavy burden of risk factors. Method: To test this hypothesis, we examined whether the association between the risk factor of lower intelligence and more severe PTSD and depression symptoms would be greater among women reporting less severe CSA (n = 15) relative to women who reported moderate (n = 54) or high (n = 31) severity CSA. Results: The evidence was consistent with this hypothesis for subjects in the low and moderate severity groups, but less so for those in the high severity group. Conclusions: Lower intelligence was a more potent risk factor for posttraumatic distress among people exposed to less severe relative to moderately severe stressors.Psycholog

Trauma Centrality and PTSD Symptom Severity in Adult Survivors of Childhood Sexual Abuse

Theorists have posited that regarding a trauma as central to one's identity leads to greater posttraumatic stress disorder (PTSD) symptom severity. To test this hypothesis, we administered the Centrality of Events Scale (CES) to women reporting a history of childhood sexual abuse (N = 102). The CES scores were correlated with PTSD symptom severity, depression severity, and self-esteem. In addition, we conducted a principal component analysis (PCA) to evaluate factors underlying the CES. The PCA yielded 3 factors reflecting (a) the centrality and integration of the trauma, (b) whether the event is regarded as a turning point in one's life story, and (c) whether the event is a reference point for expectations about the future. Each factor was associated with PTSD symptom severity.Psycholog

The Urinary 1-Hydroxypyrene Biomarker in Street Janitors Exposed to Air Quality Changes Associated with Religious Events in Madinah, Saudi Arabia

Madinah is the second most important Muslim holy city in Saudi Arabia. Exceptionally during holy months, traffic congestion and consequent air emission of several pollutant compounds mainly carcinogenic Benzo[a]pyrene (BaP) is expected to reach high levels at certain places. Inhalation of air BaP emissions is the main route of entry into the human body. Therefore, the aim of the present study was to assess a biomarker of exposure to air BaP which is urinary 1-hydroxypyrene (1-OHP) among janitors and find out the relation between this biomarker with daily exposure to air BaP, some traffic and weather factors

Cognitive Aspects of Nonclinical Obsessive-Compulsive Hoarding

Research on the cognitive variables associated with obsessive-compulsive hoarding is scarce. In this study, we investigated cognitive variables that may contribute to the maintenance and possibly etiology of hoarding. College students who characterized themselves as either "packrats" (nonclinical hoarders; n = 21) or not (control participants; n = 20) completed questionnaires assessing hoarding behavior and beliefs about hoarding, and completed a task requiring them to categorize diverse objects and trinkets of minimal value into groups. The results revealed that nonclinical hoarders, relative to control participants, rated the categorization task as significantly more stressful and difficult. Relative to control participants, hoarders took longer to complete the task and sorted objects into more categories. These findings suggest that underinclusiveness and indecisiveness, characteristic of clinical hoarders, are evident in nonclinical hoarders as well.Psycholog

A Workflow for Global Sensitivity Analysis of PBPK Models

Physiologically based pharmacokinetic (PBPK) models have a potentially significant role in the development of a reliable predictive toxicity testing strategy. The structure of PBPK models are ideal frameworks into which disparate in vitro and in vivo data can be integrated and utilized to translate information generated, using alternative to animal measures of toxicity and human biological monitoring data, into plausible corresponding exposures. However, these models invariably include the description of well known non-linear biological processes such as, enzyme saturation and interactions between parameters such as, organ mass and body mass. Therefore, an appropriate sensitivity analysis (SA) technique is required which can quantify the influences associated with individual parameters, interactions between parameters and any non-linear processes. In this report we have defined the elements of a workflow for SA of PBPK models that is computationally feasible, accounts for interactions between parameters, and can be displayed in the form of a bar chart and cumulative sum line (Lowry plot), which we believe is intuitive and appropriate for toxicologists, risk assessors, and regulators

Patterns of suicide deaths in Hungary between 1995 and 2017

Hungary has had one of the highest suicide mortality rates in the world for decades. Investigating seasonality of suicide deaths is essential as its findings could be key elements in the prevention. In our study we have analyzed the seasonal effect in suicide mortality in relation to possible risk factors in Hungary during 1995–2017. Data on the numbers of suicide deaths were obtained from a published online database. Negative binomial regression was employed to investigate the effect of possible risk factors and seasonal and annual trends in suicide rates. The seasonal effect was further investigated, adding a significant risk factor from the “initial” negative binomial regression. The suicide risk was significantly (p < 0.001) higher in men than in women (incidence rate ratio: 3.48), and it increased with age and decreased with education level. Marriage was a protective factor against suicide. Annual suicide mortality declined significantly (p < 0.001 for trend) from 36.7 (95% confidence interval: 35.5–37.9) to 16.5 (15.7–17.3) per 100,000 persons per year during the study period. Significant seasonality was found in suicide rates with a peak in late June. Similar peaks were observed at each level of each risk factor. There were differences in peaks by suicide method. The peak of non-violent suicides was in early June; suicides committed by violent methods peaked half a month later. This study suggests that there was a significant seasonal effect on suicide deaths between 1995 and 2017, which remained significant even in the presence of each risk factor. To our knowledge, this has been the first study to investigate the seasonal pattern so extensively in Hungary. Our findings confirm that the environmental effects are involved in the etiology of suicide mortality

Inter-Identity Autobiographical Amnesia in Patients with Dissociative Identity Disorder

Background: A major symptom of Dissociative Identity Disorder (DID; formerly Multiple Personality Disorder) is dissociative amnesia, the inability to recall important personal information. Only two case studies have directly addressed autobiographical memory in DID. Both provided evidence suggestive of dissociative amnesia. The aim of the current study was to objectively assess transfer of autobiographical information between identities in a larger sample of DID patients. Methods: Using a concealed information task, we assessed recognition of autobiographical details in an amnesic identity. Eleven DID patients, 27 normal controls, and 23 controls simulating DID participated. Controls and simulators were matched to patients on age, education level, and type of autobiographical memory tested. Findings: Although patients subjectively reported amnesia for the autobiographical details included in the task, the results indicated transfer of information between identities. Conclusion: The results call for a revision of the DID definition. The amnesia criterion should be modified to emphasize its subjective nature.Psycholog