Chronic Stress Experience Research Articles

A Study on the Impact of Acute Stress and Chronic Stress Experience on Depression in Low-income Mothers with Children

A Study on the Impact of Acute Stress and Chronic Stress Experience on Depression in Low-income Mothers with Children

An Elephant Among Us: The Role of Dopamine in the Pathophysiology of Fibromyalgia

Exploration of the pathophysiology underlying fibromyalgia (FM) has become an exciting field of inquiry as we strive to improve our understanding of this enigmatic disorder. While evidence of a neuro-dysregulatory state mounts and insights are gained as to potential contribution of specific neurotransmitters, a review of recent literature demonstrates that not all relevant neurotransmitters are being considered equally or with disinterest. Specifically, the potential contribution of serotonin and norepinephrine has been emphasized, ostensibly due in part to the qualified success of trials of serotonin-norepinephrine reuptake inhibitors, while a general awareness of the potential contribution of dopamine-related dysfunction lags. Indeed, the text of recent reviews, and even peer-reviewed continuing medical education test articles, have contained either scant reference or, in a majority of cases, conspicuous neglect regarding the question of dopamine’s role in FM. Despite the recent European League Against Rheumatism consensus recommendation to consider a dopamine agonist for treatment of FM1, most clinicians and even medical authorities in the field routinely fail to acknowledge the mounting evidence for a role for dopamine in the pathogenesis of FM. The proposition that a disruption of normal dopaminergic neurotransmission may make a substantial contribution to the pathophysiology of FM was initially based on 3 key observations: (1) FM has been characterized as a “stress-related” disorder due to its frequent onset and apparent exacerbation of symptoms in the context of stressful events2; (2) the experience of chronic stress results in disruption of dopaminergic activity in otherwise healthy organisms3; and (3) dopamine plays a dominant role in natural analgesia within multiple brain centers4. The first hint in the medical literature of a connection between FM and dopamine was provided by Russell, et al , who in 1992 reported lower concentrations of metabolites of dopamine, norepinephrine, and serotonin … Address reprint requests to Dr. Wood ; E-mail: pwood{at}anglerbiomedical.com

Functional Status, Chronic Stress, and Cortisol Response After Mild-to-Moderate Traumatic Brain Injury

It is well known that individuals experience difficulties with depressive symptoms and functional status after traumatic brain injury. However, it is unclear what the relationship is between these 2 phenomena and whether there is a biological explanation for. In this secondary analysis, we examined whether depressive symptoms explained postinjury functional status and whether chronic stress and salivary cortisol influenced this relationship. Participants included 75 persons within 24 months of their injury dates who were evaluated or treated in specialty clinics. All participants and a family member or significant other completed survey data, and 50 of the participants provided cortisol data. Results indicated that chronic stress, measured using Cohen's Perceived Stress Scale, completely mediated the relationship between depressive symptoms, measured using the Center for Epidemiological Studies Depression Scale, and psychological functioning, measured using the Patient Competency Rating Scale. Furthermore, those who provided cortisol data displayed hypocortisolemia in their 12-hr profile. Results from this analysis suggest that interventions focused on addressing the chronic stress experience may be important in limiting depressive symptoms and improving psychological functioning. Longitudinal study of this phenomenon is required to understand the progression of chronic stress after traumatic brain injury.

Physical and Mental Health Effects of Family Caregiving

Adverse-and even positive-outcomes in a chronic stress experience.

Chronic Stress andAssociated Coping Strategies Among Volunteer EMS Personnel

Objective. This study assessed the chronic (everyday) stress experiences andcoping strategies among volunteer Emergency Medical Services personnel. Methods. An anonymous, self-report survey using standardized measures of burnout (the Maslach Burnout Inventory) andcoping (the Coping Mechanisms Checklist) was completed by a convenience sample of volunteer Emergency Medical Services personnel serving one of six participating ambulance companies in Suffolk County, New York. Results. Survey responders included 139 of 175 volunteers who were recruited to participate (response rate = 79%). Alarming percentages of participants scored high on emotional exhaustion (92%) anddepersonalization (99%); however, 75% also reported high levels of personal accomplishment. The use of several coping strategies were concerning. Significant differences were found in coping strategies used between genders andnumber of years served; women were more likely to talk with significant others (97% vs. 81.7%, chi-square = 6.849, p < 0.001), whereas men were more likely to indicate that they pick andchoose calls to go on (67% vs. 49%, chi-square = 4.062, p = 0.044). Participants with 6+ years were more likely than those with fewer years to “keep thoughts/feelings to self” (95.6% vs. 81.2%, chi-square = 5.72, p = 0.017) and“engage in risky behaviors” (47.82% vs. 30.43%, chi-square = 3.68, p = 0.055). Approximately half of responders indicted that they do the bare minimum required to stay an active member of their ambulance company (53%). ANOVAs revealed that use of several coping strategies were significantly associated with depersonalization andpersonal accomplishment scores. Conclusion. Gender, years of experience, the types of coping strategies used, andhigh levels of depersonalization andemotional exhaustion must be considered when developing mental health programs for chronic stress among volunteer Emergency Medical Services personnel.

Stressful life events are associated with low secretion rates of immunoglobulin A in saliva in the middle aged and elderly

Whether chronic stress experience is related to downregulation of secretory immunoglobulin A (S-IgA) was tested in two substantial cohorts, one middle aged ( N = 640) and another elderly ( N = 582), comprising similar numbers of men ( N = 556) and women ( N = 666) and manual ( N = 606) and non-manual ( N = 602) workers. Participants indicated from a list of major stressful life events, up to six, they had experienced in the past 2 years. They also rated how disruptive and stressful the events were, at the time and now, as well as their perceived seriousness; the products of these impact values and event frequency were adopted as measures of stress load. From unstimulated 2-min saliva samples, saliva volume and S-IgA concentration were measured, and S-IgA secretion rate determined as their product. There was a negative association between the stress load measures and the S-IgA secretion rate, still evident following adjustment for such variables as smoking and saliva volume. The associations also withstood adjustment for sex, cohort, and household occupational status. Although these associations are small in terms of the amount of variance explained, they nonetheless suggest that chronic stress experience either decreases IgA production by the local plasma cells or reduces the efficiency with which S-IgA is transported from the glandular interstitium into saliva. Given the importance of S-IgA in immune defence at mucosal surfaces and the frequency with which infections are initiated at these surfaces, S-IgA downregulation could be a means by which chronic stress increases susceptibility to upper respiratory tract infection.

Homeostatic maintenance in excitability of tree shrew hippocampal CA3 pyramidal neurons after chronic stress.

The experience of chronic stress induces a reversible regression of hippocampal CA3 apical neuron dendrites. Although such postsynaptic membrane reduction will obviously diminish the possibility of synaptic input, the consequences for the functional membrane properties of these cells are not well understood. We tested the hypothesis that chronic stress affects the input-output characteristics and excitability of CA3 pyramidal cells. Somatic whole-cell current-clamp recording with parallel intracellular biocytin labeling was performed on CA3 neurons from in vitro hippocampal slices from male tree shrews, which were collected after 28 days of psychosocial stress exposure and compared to recordings obtained from control animals. Post hoc morphometric analysis of biocytin-labeled CA3 cells revealed branch regression, by fewer dendritic crossings and length, limited to a distance of approximately 280-340 microm from the soma only. The results from whole-cell recording indicate that chronic stress surprisingly reduced the apparent membrane time constant and input resistance 20-25%, accompanied by increased amplitude of the hyperpolarization-induced voltage "sag." All active membrane properties, including depolarization-induced action potential kinetics, complex spiking patterns, and afterhyperpolarization voltages, were indistinguishable from control recordings. Although linear association analysis confirmed that differences in geometry, such as apical length or branch number, were correlated to functional variability in properties of the AP current and voltage threshold, these changes were too marginal to be reflected in the group differences. However, the individual adrenal hormone status was associated significantly with the selective changes in subthreshold excitability. Taken together, the data provide evidence that despite long-term stress induces morphological changes, upregulates cortisol release and shifts the intrinsic membrane properties, the efficacy of somatic excitability of CA3 pyramidal neurons is largely preserved.

Differential effects of chronic stress on memory processes in the tree shrew

Unpredictable and uncontrollable stressful events have been shown to affect cognitive processes. Interestingly, only hippocampus-mediated memory processes are thought to be sensitive to the effects of chronic stress. In contrast, the hippocampus-independent memory processes have been shown to be resistant to chronic stressful experiences. A central feature of the stress response is the activation of the hypothalamus–pituitary–adrenocortical (HPA)-axis, resulting in increased plasma levels of glucocorticoids, and several studies suggested that the performance of hippocampus-mediated memory processes might be directly modulated by these adrenal steroids. We investigated the impact of chronic psychosocial stress on hippocampus-mediated and hippocampus-independent memory processes in male tree shrews. By using a modified holeboard we followed memory performance during 23 weeks of alternating stress-free and stressful conditions. This schedule was designed to mimic a more realistic situation with stress-free conditions being sequentially interrupted by challenging events. The results indicate that chronic stress differentially affects hippocampus-mediated and hippocampus-independent memory processes in tree shrews. While hippocampus-independent memory processes remained unimpaired throughout the study, hippocampus-mediated memory was persistently impaired, not only during stress periods but also during recovery periods. This persistent impairment seems not to be exclusively triggered by glucocorticoids because urinary free cortisol concentration returned to normal during recovery periods. The present study is the first to evaluate the consequences of sequential stress exposure on memory performance in animals. Apparently, the mechanisms modulating cognitive processes are far from being understood and need a very systematic analysis in animal models with a high face and predictive validity to human stress-related memory disorders.

Chronic work stress, sickness absence, and hypertension in middle managers: General or specific sociological explanations?

The issue of differential prediction of health outcomes by sociological models of work stress has received little attention so far. This paper argues, both on theoretical and empirical grounds, that active coping with the experience of chronic work stress is more likely to be associated with physical health consequences of sustained autonomic arousal such as hypertension, whereas passive coping may a cross-sectional study on 189 male middle-aged (40–55, 48.3 ± 4.6 years) middle managers in a car-producing company in Germany, this hypothesis is tested in the framework of the theoretical model of effort-reward imbalance at work. More specifically, the simultaneous manifestation of high effort and low reward at work, indicative of active coping, is expected to statistically predict the risk of being hypertensive. Conversely, suffering from low occupational rewards in the absence of signs of sustained effort, indicative of passive coping, is expected to predict sickness absence (SA) behavior. Multivariate odds ratios (OR) derived from logistic regression analysis and adjusted for important confounders indicate that three measures of low reward are associated with short-term SA (OR ranging from 3.30 to 9.15), that one measure of low reward is associated with long-term SA (OR: 2.67) and that two measures of low reward are associated with number of SA episodes (OR 4.05 and 6.33), whereas no indicator of high effort at work is significantly associated with SA. On the other hand, the OR of being hypertensive is 5.77 in middle managers who suffer from high effort and low reward simultaneously. In conclusion, a sociological model of work stress which allows for differential prediction of health outcomes according to the important notions of active versus passive coping with work demands finds preliminary empirical support.

The relationship between hostility and beta-adrenergic receptor physiology in health young males.

We examined the relationship between hostility and mononuclear leukocyte (MNL) beta-adrenergic receptor function in a sample of young healthy males. Thirty subjects were selected for having scored above 20 (N = 11) and below 14 (N = 19) on the Cook-Medley Hostility (Ho) scale. MNL beta-adrenergic receptor function was characterized in terms of receptor density (Bmax) and ligand-binding affinity (Kd) in homogenized cells, and intracellular cyclic adenosine monophosphate (cAMP) responses to saline, isoproterenol, and forskolin in whole cells. Subjects also completed the Multidimensional Anger Inventory (MAI), which assesses dimensions of anger. Relative to men with low Ho scores, men with Ho scores above 20 showed lower receptor number and greater forskolin-stimulated cAMP. Moreover, high hostile men reported a greater frequency of anger, longer duration of anger, more frequent brooding, and a hostile outlook. These data indicate that adrenergic receptor down-regulation is associated with hostility. This association may be linked to hostile persons' propensity for excessive and prolonged neuroendocrine responses to either psychological stressors or the experience of chronic stress associated with frequent and prolonged bouts of anger.

A comparison of the behavioral effects of minaprine, amphetamine and stress.

Different types of clinically effective antidepressants prevent the behavioral effects of experimental stress, and some of these treatments affect mesolimbic dopamine (DA) functioning. Animal studies have demonstrated that repeated psychostimulant administration and repeated or chronic stressful experiences also affect mesolimbic DA functioning. These results could suggest homologies among stress, psychostimulants and antidepressants. The present experiments show that either repeated stress (120 min restraint daily for 10 consecutive days) or subchronic treatment with the antidepressant minaprine (5 mg/kg daily for 10 consecutive days) significantly reduced the inhibitory effect of 120 min of restraint on climbing, a behavioral response dependent on mesolimbic DA functioning. However, the antidepressant did not induce the altered sensitivity of presynaptic DA receptors promoted by repeated stress. Chronic stressful experience (13 days of food restriction) and repeated amphetamine (2.5 mg/kg daily for 10 consecutive days) were as effective as subchronic minaprine in reducing immobility in the Porsolt's swimming test. However, whilst both stress and amphetamine enhanced struggling, minaprine promoted swimming. Finally, chronically stressed mice and mice pretreated with amphetamine showed enhanced sensitivity to amphetamine-induced locomotion, whilst this effect was absent in animals pretreated with the antidepressant. These results indicate that although chronic and repeated stress as well as amphetamine have some antidepressant-like behavioral effects, their mode of action could be different from that of clinically active substances.

Endocrine Correlates of Stress Vulnerability

Psychological stress is implicated as one element in a constellation of risk factors for the development and maintenance of psychosomatic disease. Endocrine responses to stressful experience vary widely among individuals, and may account for some of the individual variability in vulnerability to development of psychosomatic symptoms under stress. Endocrine stress responsiveness probably has a large genetic component, but is also known to be modifiable by prolonged and/or profound stressful experience. Social and cognitive factors influence the pituitary-adrenal response to stress, and sex differences may also be significant. It may be possible to develop specific tests of endocrine responsiveness, perhaps incorporating psychological and pharmacological challenges, that may serve as markers of chronic stress experience or of vulnerability to psychosomatic disorders.