Chronic stress and natural killer cell activity after exposure to traumatic death

The epidemiology of finding a dead body: reports from inner-city Baltimore, Maryland US

In the US, there are no national statistics on encountering a dead body, which can be viewed as a measure of community health and a stressful life event. Participants for an HIV prevention intervention targeting drug users were recruited in areas of inner-city Baltimore, Maryland. Nine hundred and fifty-one respondents, most with a history of drug use, were asked "have you ever found a dead body?" and 17.0% reported they had. Leading causes of death were: violence (37%), natural causes (22.2%), drug overdose (21.6%), accidental death (3.1%), and suicide (2.5%). In multivariate logistic models, respondents with longer history of drug use and more roles in a drug economy were more likely to be exposed to a dead body. The study results suggest that this population has a high level of experiences with mortality associated with violence and drugs. To obtain a better understanding of community health, future studies should assess not only morbidity and mortality, but also how death and illness is experienced by the community.

Exposure, probable PTSD and lower respiratory illness among World Trade Center rescue, recovery and clean-up workers

BACKGROUND

Thousands of rescue and recovery workers descended on the World Trade Center (WTC) in the wake of the terrorist attack of September 11, 2001 (9/11). Recent studies show that respiratory illness and post-traumatic stress disorder (PTSD) are the hallmark health problems, but relationships between them are poorly understood. The current study examined this link and evaluated contributions of WTC exposures.

METHOD

Participants were 8508 police and 12 333 non-traditional responders examined at the WTC Medical Monitoring and Treatment Program (WTC-MMTP), a clinic network in the New York area established by the National Institute for Occupational Safety and Health (NIOSH). We used structural equation modeling (SEM) to explore patterns of association among exposures, other risk factors, probable WTC-related PTSD [based on the PTSD Checklist (PCL)], physician-assessed respiratory symptoms arising after 9/11 and present at examination, and abnormal pulmonary functioning defined by low forced vital capacity (FVC).

RESULTS

Fewer police than non-traditional responders had probable PTSD (5.9% v. 23.0%) and respiratory symptoms (22.5% v. 28.4%), whereas pulmonary function was similar. PTSD and respiratory symptoms were moderately correlated (r=0.28 for police and 0.27 for non-traditional responders). Exposure was more strongly associated with respiratory symptoms than with PTSD or lung function. The SEM model that best fit the data in both groups suggested that PTSD statistically mediated the association of exposure with respiratory symptoms.

CONCLUSIONS

Although longitudinal data are needed to confirm the mediation hypothesis, the link between PTSD and respiratory symptoms is noteworthy and calls for further investigation. The findings also support the value of integrated medical and psychiatric treatment for disaster responders.

Natural killer cell cytotoxicity and lymphocyte perforin expression in veterans with posttraumatic stress disorder

OBJECTIVE

To examine the effect of posttraumatic stress disorder (PTSD) on the measures of immune function and the hypothalamic-pituitary-adrenal axis components, and to determine whether additional life stressors affect measured variables.

METHODS

We simultaneously examined the natural killer cell cytotoxicity (NKCC), perforin and glucocorticoid receptor (GCR) expression in natural killer (NK) and cytotoxic T (CD8) cells, as well as serum cortisol concentration in a group of Croatian war veterans with chronic, combat-related PTSD (n=29) and a group of healthy, age-matched men (n=13). PTSD patients were divided into two subgroups: compensation-seeking (n=15) and retired or compensation non-seeking (n=14) subjects. The former includes those involved in the process of getting disability-based army retirement as an additional life stressor.

RESULTS

NKCC was decreased in both PTSD groups when compared to controls. Impairment of NKCC could not be attributed to the perforin expression as perforin was not decreased in comparison to controls. Moreover, the increased level of perforin was recorded in NK cells of retired PTSD subjects. Both PTSD groups shared an increased relative quantity of GCR in lymphocytes, whereas no difference between the groups in the baseline levels of serum cortisol was observed.

CONCLUSIONS

Diminished NKCC was not accompanied by perforin insufficiency in PTSD subjects, and other causes should be examined. An additional life stressor does not contribute considerably to either immune or endocrine system related changes.

Religiosity and the expansion of caregiver stress

We present a stress process framework as a model for understanding how religiosity may influence the expansion of stress. Survey data from informal caregivers to a spouse with Alzheimer's disease or a related dementia (n = 200) were analyzed to observe the relationships among three variables: (1) care-related stress, (2) religiosity, and (3) depression. This sample, which has a mean age of 73 years, demonstrates high rates of self-described religiosity, church attendance and frequency of prayer. Using these criteria, women and racial/ethnic minority caregivers are the most religious. In a series of multivariate analyses, we found strong evidence to suggest that there is an expansion of care-related stressors leading to depression in this sample. Religiosity, as measured here, appears to be largely unrelated to stress and stress expansion. We found no evidence to suggest that it moderates stress expansion. However, these data do suggest that one stressor--feelings of role overload--is correlated with greater levels of self-perceived religiosity, which among caregivers who have health problems of their own is associated with greater depressive symptomatology. Thus, for a sub-sample of these caregivers, we find weak evidence of a mediation effect wherein one subjective, non-organizational dimension of religiosity is a conduit of the harmful effects of stress (rather than a suppressor). Results and data limitations are discussed in relation to better assessing the role of religiosity and spirituality in the experience of the stress process.

Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stressors were associated with suppression of both cellular and humoral measures. Effects of event sequences varied according to the kind of event (trauma vs. loss). Subjective reports of stress generally did not associate with immune change. In some cases, physical vulnerability as a function of age or disease also increased vulnerability to immune change during stressors.

Psychological stress and the human immune system: a meta-analytic study of 30 years of inquiry

The present report meta-analyzes more than 300 empirical articles describing a relationship between psychological stress and parameters of the immune system in human participants. Acute stressors (lasting minutes) were associated with potentially adaptive upregulation of some parameters of natural immunity and downregulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stressors were associated with suppression of both cellular and humoral measures. Effects of event sequences varied according to the kind of event (trauma vs. loss). Subjective reports of stress generally did not associate with immune change. In some cases, physical vulnerability as a function of age or disease also increased vulnerability to immune change during stressors.

Perceived social support and secondary traumatic stress symptoms in emergency responders

This study investigated prevalence rates of secondary traumatic stress symptoms in Israeli Police forensic technicians, and the relationship between these symptoms and perceived social support as well as perceived severity of prior trauma (combat, work, personal). Ninety technicians from the Israeli Police Forensic Investigation Unit participated in the study. Intrusion and avoidance measured within the medium range of severity, whereas distress symptoms were below clinical threshold. Intrusion was significantly related to avoidance, distress, and the perceived severity of prior personal and work-related exposure. No significant relationship was found between perceived social support and secondary traumatic stress symptoms. The data suggest that this cohort utilized avoidance effectively as a defense against intrusion.

Post-traumatic stress disorder: advances in psychoneuroimmunology

Exposure to trauma can result in immune dysregulation, and increasing evidence suggests that there are immune alterations associated with post-traumatic stress disorder (PTSD). However, the exact nature of these immune findings in PTSD has not been defined. The study of psychoneuroimmunology in PTSD is relevant not only for understanding the biological underpinnings of this disorder, but also for establishing the nature of the associations between PTSD and other medical and psychiatric illnesses.

Posttraumatic stress disorder revisited

In this review we trace the history of and professional discussion on psychological traumatization due to "railroad spine syndrome," "shell-shock syndrome," and "war neuroses," as well as the more or less endemic "posttraumatic stress disorder" of today. Psychological trauma engenders longlasting consequences in the biological, intrapsychic, and social organization of individuals. Medical experts have reported a shift in attention from exogenous to endogenous and back to exogenous causes, as indicated by new diagnostic systems (DSM-IV and ICD-10). As far as the relevant literature is concerned, the medical profession demonstrates the same partial amnesia as their patient counterparts. The purpose of this review is to overcome this fragmented memory and thus reach a more integrated view of what constitutes psychological trauma by reviewing trauma-related articles published in Psychosomatic Medicine. Moreover, we point out the direction in which research is desperately needed and ought to develop.

Psychoneuroimmunology and psychosomatic medicine: back to the future

OBJECTIVE

Although psychological modulation of immune function is now a well-established phenomenon, much of the relevant literature has been published within the last decade. This article speculates on future directions for psychoneuroimmunology research, after reviewing the history of the field.

METHODS

This review focuses on human psychoneuroimmunology studies published since 1939, particularly those that have appeared in Psychosomatic Medicine. Studies were clustered according to key themes, including stressor duration and characteristics (laboratory stressors, time-limited naturalistic stressors, or chronic stress), as well as the influences of psychopathology, personality, and interpersonal relationships; the responsiveness of the immune system to behavioral interventions is also addressed. Additionally, we describe trends in populations studied and the changing nature of immunological assessments. The final section focuses on health outcomes and future directions for the field.

RESULTS

There are now sufficient data to conclude that immune modulation by psychosocial stressors or interventions can lead to actual health changes, with the strongest direct evidence to date in infectious disease and wound healing. Furthermore, recent medical literature has highlighted a spectrum of diseases whose onset and course may be influenced by proinflammatory cytokines, from cardiovascular disease to frailty and functional decline; proinflammatory cytokine production can be directly stimulated by negative emotions and stressful experiences and indirectly stimulated by chronic or recurring infections. Accordingly, distress-related immune dysregulation may be one core mechanism behind a diverse set of health risks associated with negative emotions.

CONCLUSIONS

We suggest that psychoneuroimmunology may have broad implications for the basic biological sciences and medicine.

Autonomic and neuroendocrine responses to mild psychological stressors: effects of chronic stress on older women

We investigated autonomic and endocrine responses to acute stressors in 27 women who were or are presently caring for a spouse with a progressive dementia (high chronic stress) and 37 noncaregivers who were category matched for age and family income (low chronic stress). Measures were taken before (low acute stress) and in response to brief laboratory stressors (high acute stress). We replicated prior research showing that caregivers report greater stress, depression, and loneliness than the comparison groups, and acute stressors elevate autonomic and neuroendocrine activity. We also found that caregivers, relative to noncaregivers, exhibited shorter preejection periods and elevated blood pressure and heart rate, but the magnitude of autonomic and neuroendocrine reactivity to the experimental stressors was comparable across these groups. This pattern of autonomic differentiation replicates prior research showing that caregivers are characterized by higher sympathetic activation than noncaregivers and suggests that the effects of chronic stress on physiological reactivity may be a less robust effect in older adults.

Similarity of prior trauma exposure as a determinant of chronic stress responding to an airline disaster

The cumulative effects of trauma were examined in 108 workers at the site of a major air disaster at 4 time points over a year following the crash. The influence of trauma history on chronic distress and physiological arousal associated with the crash were examined. Stress levels were expected to differ on the basis of the similarity of prior trauma exposure to work at the crash site. Prior traumatic exposure that was "dissimilar" to this type of work was associated with greater vulnerability to crash-related stress, that is, more distress and crash-related intrusions during the year following the crash. Accumulation of a variety of different traumatic experiences appeared to sensitize workers to the new stressor and to perpetuate chronic stress. Understanding the role of trauma history is important for improving intervention efforts aimed at alleviating stress following a trauma.

The potential role of hypocortisolism in the pathophysiology of stress-related bodily disorders

Representing a challenge for current concepts of stress research, a number of studies have now provided convincing evidence that the adrenal gland is hypoactive in some stress-related states. The phenomenon of hypocortisolism has mainly been described for patients, who experienced a traumatic event and subsequently developed post-traumatic stress disorder (PTSD). However, as presented in this review, hypocortisolism does not merely represent a specific correlate of PTSD, since similar findings have been reported for healthy individuals living under conditions of chronic stress as well as for patients with several bodily disorders. These include chronic fatigue syndrome, fibromyalgia, other somatoform disorders, rheumatoid arthritis, and asthma, and many of these disorders have been related to stress. Although hypocortisolism appears to be a frequent and widespread phenomenon, the nature of the underlying mechanisms and the homology of these mechanisms within and across clinical groups remain speculative. Potential mechanisms include dysregulations on several levels of the hypothalamic-pituitary adrenal axis. In addition, factors such as genetic vulnerability, previous stress experience, coping and personality styles may determine the manifestation of this neuroendocrine abnormality. Several authors proposed theoretical concepts on the development or physiological meaning of hypocortisolism. Based on the reviewed findings, we propose that a persistent lack of cortisol availability in traumatized or chronically stressed individuals may promote an increased vulnerability for the development of stress-related bodily disorders. This pathophysiological model may have important implications for the prevention, diagnosis and treatment of the classical psychosomatic disorders.

Identifying human remains following an air disaster: the role of social work

An area of disaster response with high risk of inducing trauma in response workers is recovering and identifying human remains. Following a review of the literature addressing the significant stressors associated with handling dead bodies, we present a case study which describes professional social work intervention and support to disaster response workers and volunteers assigned to the morgue following a major air disaster. A primary task was helping workers cope with the unique stresses associated with recovering dead bodies. Opportunities for social workers to use their professional skills for disaster response work is discussed along with recommendations for social work education.

Cues, frequency, and the disturbing nature of intrusive thoughts: patterns seen in rescue workers after the crash of Flight 427

Intrusive thoughts have been identified as key elements of chronic or traumatic stress, but many questions remain about how they operate and what causes persistence of disturbing intrusions. The present study considers these questions, examining the impact of having intrusive thoughts that are cued by stimuli in one's environment as opposed to uncued intrusions that seem to "come out of the blue." In addition, this research evaluates the extent to which distress accompanying intrusive thoughts shortly after a traumatic event predicts persistence of intrusions over time. Rescue workers who responded to the crash of Flight 427 were studied 4 to 8 weeks, and 6, 9, and 12 months after the disaster. Participants who reported crash-related thoughts that were not prompted by cues showed higher levels of distress than those reporting only cued thoughts or those reporting neither. The magnitude of distress that these thoughts caused in the first 2 months after the crash was important in predicting subsequent frequency of unwanted thoughts. The presence or absence of cues and their role in the maintenance of distress also is discussed.

Assessment of characteristics of intrusive thoughts and their impact on distress among victims of traumatic events

OBJECTIVE

This study examines the psychometric properties of the Intrusive Thoughts Questionnaire (ITQ) and its utility as a predictor of distress among trauma victims.

METHOD

Victims of three types of trauma, a motor vehicle accident (N = 115), a hurricane (N = 182), and recovery work after an airline disaster (N = 159), completed the ITQ along with the Impact of Event Scale (IES) and the Symptom Checklist-90, Revised (SCL-90-R), at several different time points after their exposure.

RESULTS

The ITQ was a reliable and valid instrument that was positively related to concurrent measures of distress as well as a predictor of long-term stress responding. Characteristics of intrusive thoughts reflecting the extent to which they were unwanted or controllable, were identified as key determinants of distress.

CONCLUSIONS

The ITQ is a useful adjunct to current measures of intrusions, allowing for greater specificity in analyses of responses to trauma. Evaluation of characteristics of intrusions indicated that frequency of intrusions was neither the only predictor of distress nor the best predictor of trauma-related outcomes.