Fear of anxiety as a partial mediator of the relation between trauma severity and PTSD symptoms

Post-Hurricane Distress Scale (PHDS): A Novel Tool for First Responders and Disaster Researchers

OBJECTIVE

The aim of this study was the construction and validation of a novel research instrument to quantify the degree of post-hurricane trauma and distress in an affected population. The Post-Hurricane Distress Scale (PHDS) has quantitative measures of both acute and prolonged distress, attributable to meteorological and hydrological disasters.

METHODS

A careful evaluation of existing questionnaires, as well as extensive canvasing of the post-Maria population of Puerto Rico, availed the construction of the PHDS. The PHDS consists of 20 items, organized into 4 subscales. The PHDS was pre-validated (n=79), revised, and then distributed to a broad sampling of the post-Hurricane Maria Puerto Rican population (n=597). Validation, including factor analysis, analyses of concurrent validity, discriminant validity, and internal reliability, was performed.

RESULTS

After comparing various scales, factor loading profiles, concurrent validities, and models of fit, we show that the PHDS is best scored as a single 0-6 distress scale. When compared with the Traumatic Exposure Severity Scale, the PHDS shows superior concurrent validity, more accurately predicting scores for the Peritraumatic Distress Inventory, Impact of Event Scale - Revised, and Generalized Anxiety Disorder 7 Scale. The PHDS shows good internal reliability and discriminant validity.

CONCLUSIONS

The PHDS represents a novel, useful instrument for disaster first-responders and researchers. The prompt identification of high-risk populations is possible using this instrument. (Disaster Med Public Health Preparedness. 2019;13:82-89).

The neural basis of olfactory function and its relationship with anhedonia in individuals with schizotypy: An exploratory study

Previous studies have established a linkage between olfactory deficits and negative symptoms in schizophrenia. However, it is not known whether olfactory function is associated with hedonic traits in individuals with schizotypy. Seventeen individuals with schizotypy and 18 age- and sex-matched controls participated in this study. Hedonic traits were assessed with the Chapman Scales for Physical and Social Anhedonia (CSAS and CPAS). Olfactory function was assessed with the Sniffin' Stick Test (olfactory threshold, odour discrimination and odour identification). All participants undertook a structural imaging scan for grey matter volume measurements. Individuals with schizotypy had significantly higher CSAS and CPAS scores than healthy controls. They had normal olfactory function. Their odour identification ability was inversely correlated with physical and social anhedonia. The volume of the right parahippocampal gyrus was positively associated with odour identification ability, and negatively associated with physical and social anhedonia. Furthermore, mediation analysis suggested that odour identification ability influences anhedonia through its effect on the right parahippocampal gyrus. No such relationship was found in controls. These findings suggest that there is a relationship between odour identification and anhedonia in individuals with schizotypy, and the association may be mediated by parahippocampal gyrus volume.

Mediators of Initial Acute and Later Posttraumatic Stress in Youth in a PICU

OBJECTIVES

Youth in a PICU and their parents may experience initial symptoms of acute stress disorder and later symptoms of posttraumatic stress disorder. The objective of this study was to examine potential mediators of these conditions, including youth anxiety, depression, negative affect, and hospital fear, as well as parent anxiety and depression

DESIGN

This study involved a short longitudinal design that encompassed initial assessments in a PICU setting and later assessments 4-7 weeks after discharge.

SETTING

Youth and their parents completed dependent measures in the hospital and at follow-up at the youth's home or an outpatient clinic setting.

PATIENTS

Fifty youth aged 9-17 yrs were admitted to a PICU for respiratory illness/asthma (30.0%), trauma (26.0%), surgery and after surgery recovery (20.0%), infections/viral illness (8.0%), neurologic disorder (6.0%), or other (10.0%). Parents (n = 50) were also assessed.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Measures were utilized for youth anxiety, acute stress, depression, negative affect, posttraumatic stress, and hospital fear, as well as parent anxiety, acute stress, depression, and posttraumatic stress. Some youth (26%) and parents (24%) had substantial posttraumatic stress disorder symptoms develop. Youth acute stress disorder symptoms in the PICU predicted later youth posttraumatic stress disorder symptoms, parent acute stress disorder symptoms in the PICU predicted later parent posttraumatic stress disorder symptoms, and youth acute stress disorder symptoms in the PICU predicted later parent posttraumatic stress disorder symptoms. Youth anxiety, negative affect, and hospital fear mediated initial youth acute stress disorder symptoms and later youth posttraumatic stress disorder symptoms.

CONCLUSIONS

Youth in a pediatric intensive care unit are at increased risk for posttraumatic stress disorder and should be screened for acute stress disorder.

Measuring exposure in Hurricane Katrina: a meta-analysis and an integrative data analysis

To date there is no consensus on the operationalization of exposure severity in the study of the impact of natural disasters. This is problematic because incomplete and inconsistent measurement of exposure limits the internal and external validity of disaster studies. The current paper examined the predictive validity of severity measures in two interrelated studies of Hurricane Katrina survivors. First, in a meta-analysis of eight studies that measured both exposure severity and posttraumatic stress, the effect size was estimated to be r = .266. The moderating effects of sample and study characteristics were examined and we found that minority status and number of stressors assessed were significant moderators. Second, in an integrative data analysis of five independent samples of Hurricane Katrina survivors, the impact of specific disaster-related stressors on mental health was compared. Threat to physical integrity of self and others were found to have the strongest association with posttraumatic stress (PTS) and general psychological distress (GPD). The lack of basic necessities, such as food, water, and medical care, and loss of pet were also found to be strongly associated with both PTS and GPD. The results from the two studies are integrated and their implication for disaster research and relief are discussed.

Fear conditioning and extinction: emotional states encoded by distinct signaling pathways

Conditioning and extinction of fear have traditionally been viewed as two independent learning processes for encoding representations of contexts or cues (conditioned stimuli, CS), aversive events (unconditioned stimuli, US), and their relationship. Based on the analysis of protein kinase signaling patterns in neurons of the fear circuit, we propose that fear and extinction are best conceptualized as emotional states triggered by a single CS representation with two opposing values: aversive and non-aversive. These values are conferred by the presence or absence of the US and encoded by distinct sets of kinase signaling pathways and their downstream targets. Modulating specific protein kinases thus has the potential to modify emotional states, and hence, may emerge as a promising treatment for anxiety disorders.