Depression in caregivers of demented patients is associated with altered immunity: impaired proliferative capacity, increased CD8+, and a decline in lymphocytes with surface signal transduction molecules (CD38+) and a cytotoxicity marker (CD56+ CD8+)

Impact of psychological stressors on natural killer cell function: A comprehensive analysis based on stressor type, duration, intensity, and species

Patients with natural killer (NK) cell deficiency or dysfunction are more susceptible to infections by Herpesviridae viruses, herpesvirus-related cancers, and macrophage activation syndromes. This review summarizes research on NK cell dysfunction following psychological stress, focusing on stressor type, duration, age of exposure, and species studied. Psychological stressors negatively affect NK cell activity (NKCA) across species. Prolonged stress leads to more significant decreases in NK cell number and function, with rehabilitation efforts proving ineffective in reversing these effects. Early life and prolonged stress exposure particularly increases the risk of infections and cancer due to impaired NKCA. The review also highlights that stress impacts males and females differently, with females exhibiting a more immunosuppressed NK cell phenotype. Notably, mice respond differently compared to humans and other animals, making them unsuitable for NK cell stress-related studies. Most studies measured NKCA using cytolytic assays against K-562 or YAC-1 cells. Although the exact mechanisms of NK cell dysfunction under stress remain unclear, potential causes include reduced release of secretory lysosomes with perforin or granzyme, impaired NK cell synapse formation, decreased expression of synapse-related molecules like CD2 or LFA-1 (CD11a), altered activating receptor expression, and dysregulated signaling pathways, such as decreased Erk1/2 phosphorylation and NFkB signaling. These mechanisms are not mutually exclusive, and future research is needed to clarify these pathways and develop therapeutic interventions for stress-induced immune dysregulation.

In vitro proinflammatory gene expression predicts in vivo telomere shortening: A preliminary study

The chronic psychological stress of caregiving leads to higher risks for many diseases. One of the mechanisms through which caregiving is associated with disease risk is chronic inflammation. Chronic inflammation may accelerate cellular aging via telomere dysfunction and cell senescence, although this has not been examined in human cells from healthy people. We examined peripheral blood mononuclear cells (PBMCs) from 20 healthy mothers of children with autism (caregivers) and 19 mothers of neurotypical children (controls) in an in vitro culture system where PBMCs were stimulated with phytohaemagglutinin (PHA). We measured RNA expression levels of a panel of immune function genes before and after PHA stimulation, as well as telomere length from PBMCs collected from the participants at baseline and 15 months later. Caregivers and controls had similar gene expression profiles in unstimulated PBMCs, but after PHA stimulation, caregivers had increased RNA levels of the master inflammatory regulator NF-κB and its proinflammatory cytokine targets IL-1β, IL-6 and its receptor IL-6R as well as inflammatory chemokines IL-8, CXCL1 and CXCL2. Gene expression analysis suggested caregivers have increased Treg and Th17 T cell differentiation. Additionally, key signaling molecules involved in the upregulation of COX-2, a critical enzyme in the synthesis of the inflammatory mediator prostaglandin, were elevated. When both groups were examined together, higher expression levels of proinflammatory genes were associated with shorter telomere length in PBMCs from blood drawn 15 months later, independent of baseline telomere length. Taken together, these results suggest that chronic stress is associated with an exaggerated inflammatory response in PBMCs, which in turn is associated with shorter telomere length measured from PBMCs collected 15 months later. To our knowledge, this is the first human study that shows increased proinflammatory expression predicts future telomere shortening.

Attachment orientations and psychological adjustment of parents of children with cancer: A matched-group comparison

OBJECTIVE

To investigate the impact of childhood cancer on parents' adult attachment, social support, marital adjustment, anxiety, and depression.

METHODS

30 parents of children with childhood cancer and 30 matched controls completed the following questionnaires: Experiences in Close Relationships-Revised, Dyadic Adjustment Scale-4, Multidimensional Scale of Perceived Social Support, State-Trait Anxiety Inventory - form Y, and Beck Depression Inventory.

RESULTS

Parents of children with childhood cancer had a significantly lower dyadic adjustment than controls, and higher levels of insecure-avoidant attachment, state anxiety, and depression.

CONCLUSION

It is important for health-care personnel to take into account these parents' propensity to show increased levels of avoidant attachment during children's treatment to foster effective communication and supportive relationships between clinicians, pediatric patients, and parents.

A systematic review of the psychobiological burden of informal caregiving for patients with dementia: Focus on cognitive and biological markers of chronic stress

As the physiological impact of chronic stress is difficult to study in humans, naturalistic stressors are invaluable sources of information in this area. This review systematically evaluates the research literature examining biomarkers of chronic stress, including neurocognition, in informal dementia caregivers. We identified 151 papers for inclusion in the final review, including papers examining differences between caregivers and controls as well as interventions aimed at counteracting the biological burden of chronic caregiving stress. Results indicate that cortisol was increased in caregivers in a majority of studies examining this biomarker. There was mixed evidence for differences in epinephrine, norepinephrine and other cardiovascular markers. There was a high level of heterogeneity in immune system measures. Caregivers performed more poorly on attention and executive functioning tests. There was mixed evidence for memory performance. Interventions to reduce stress improved cognition but had mixed effects on cortisol. Risk of bias was generally low to moderate. Given the rising need for family caregivers worldwide, the implications of these findings can no longer be neglected.

Biopsychological Markers of Distress in Informal Caregivers

Background. Thirty caregiving wives participated in a study of caregiving distress and negative mood (depressive symptoms) by making diary entries on stressful caregiving situations and collecting saliva samples 4 times a day. At the end of the 7-day study period, caregivers’ salivary cortisol production was compared with their diary entries and correlated with pencil and paper self-report scores of caregiver distress and depressive symptoms.

Findings. Despite the inability to control a number of factors thought to confound cortisol production (exercise, smoking, alcohol ingestion, and prescription medications), there was a statistically significant difference between No Caregiving and Caregiving cortisol, F( 1,739) = 7.67, P = 0.006, with cortisol production higher when caregiving events occurred. However, efforts to code specific types of caregiving situations (e.g., 1 = indirect care; 4 = AD problem behavior care) did not further differentiate cortisol production. Although caregivers’ self-reports for the same 7-day period indicated they were depressed, pencil-and-paper measures of distress and negative affect were not significantly correlated with cortisol production.

Conclusions and Recommendations. The finding that this caregiving group was significantly stressed by caregiving, as evidenced by increased cortisol production during caregiving episodes, verifies the importance of further exploration of specific caregiving situations as contributory factors in caregiver health and well-being. In that saliva is a relatively economical and comparatively noninvasive biological data source for community-based stress studies, methodological limitations of the study are identified and 5 recommendations are made for future biological marker studies of caregiver distress in community-based settings.

Pilot Study of Parent Psychophysiologic Outcomes in Pediatric Hematopoietic Stem Cell Transplantation

BACKGROUND

Parents of children undergoing hematopoietic stem cell transplantation (HSCT) are at risk for psychological distress. This distress may result in aberrant immune, inflammatory, or endocrine effects. These physiologic outcomes have not been reported previously.

MAIN OBJECTIVE

The aim of this study is to examine the feasibility of longitudinal testing of psychophysiological parameters of stress in parents of children undergoing HSCT.

METHODS

This pilot study was conducted at a large children's hospital in the Midwest and included parents of children who received autologous or allogeneic HSCT. Time points included before the start of HSCT conditioning and day +30, +60, and +100. Outcome variables included parent-perceived stress, lymphocyte subsets, C-reactive protein (CRP), proinflammatory cytokines, salivary cortisol, and salivary amylase. Effect sizes were calculated for each outcome.

RESULTS

Twelve parent-child dyads were enrolled (10 mothers, 2 fathers). Missing data were minimal. Parent-perceived stress significantly increased from pre-HSCT through day +100, and parent CD3+ T-lymphocyte counts decreased from pre-HSCT through day +100. No significant effects were observed for salivary studies, CRP, or proinflammatory cytokines. Effect sizes ranged from 1.23 (perceived stress) to 0.07 (CRP).

CONCLUSION

The results of this study suggest that it is feasible longitudinally measure parent psychophysiologic outcomes in the pediatric HSCT setting. In addition, parent-perceived stress increased linearly from start of conditioning through day +100, whereas parent T-lymphocyte counts decreased concurrently.

IMPLICATIONS FOR PRACTICE

Routine psychological and physical health screening of parents of children undergoing HSCT is needed. Multidisciplinary psychosocial support services should be offered to parents at regular intervals during their child's HSCT.

Comparative Analysis of Informal Caregiver Burden in Advanced Cancer, Dementia, and Acquired Brain Injury

CONTEXT

Measurement and improvement of informal caregiver burden are central aims of policy and intervention. Burden itself is a complex construct, and total burden can differ by patient diagnosis, although how diagnosis affects different aspects of caregiver subjective burden is unclear.

OBJECTIVES

To compare the subjective burden of caregivers across three diagnostic groups using the 22-item Zarit Burden Inventory.

METHODS

We performed a secondary analysis of pooled cross-sectional data from four U.K. studies of informal caregivers of patients with advanced cancer (n = 105), dementia (n = 131), and acquired brain injury (ABI) (n = 215). Zarit Burden Inventory totals, subscales (personal and role strain), and individual mean scores were compared between diagnostic groups using the general linear model, adjusting for caregiver characteristics.

RESULTS

Caregiver age (mean years [SD]: cancer 66.1 [12.0]; dementia 61.9 [13.4]; and ABI 53.8 [10.9]) differed significantly across diagnostic groups (P < 0.001); 81.9%, 36.6%, and 59.1% of caregivers were spouse/partners, respectively (P < 0.001). Total burden was highest in ABI caregivers and lowest in cancer (mean total score [SD]: cancer 23.3 [13.4]; dementia 27.9 [16.4]; and ABI 39.1 [17.3]) (P < 0.001). Subscale scores showed similar patterns (mean personal and role subscale scores [SD]: cancer 11.8 [6.9], 5.8 [4.8]; dementia 14.4 [8.8], 7.3 [5.7]; and ABI 18.7 [9.1], 11.8 [6.0]) (P < 0.001 for both subscales). Most (17 of 22) individual item scores differed by diagnosis group (P < 0.05), except concepts of duty, responsibility, and perception of financial situation.

CONCLUSION

Our data show that total, subscale, and most individual elements of caregiver subjective burden differ between cancer, dementia, and ABI caregivers. This should be considered when designing future intervention strategies to reduce caregiver burden in these groups.

Addressing Everyday Challenges: Feasibility of a Family Caregiver Training Program for People With Dementia

OBJECTIVE. The purpose of this study was to examine the feasibility and efficacy of the Family Caregiver Training Program for assisting with the basic activities of daily living of people with dementia.

METHOD. A one-group pretest–posttest research design with a 3-mo follow-up was used to examine the efficacy of a manualized education program for caregivers. The 6-hr training was delivered to 72 family caregivers over 3 consecutive weeks (2 hr/wk) by trained clinicians.

RESULTS. Caregivers showed a significant gain in knowledge of how to effectively assist with communication and nutrition, t(52) = 7.05, p &lt; .000; transfers and toileting, t(45) = 3.10, p &lt; .003; and bathing and dressing, t(44) = 2.71, p &lt; .01, of their care recipients.

CONCLUSION. Our findings demonstrate that this manualized intervention protocol is a promising method of equipping family members with the skills needed to face their everyday challenges in caring for people with dementia.

Anger expression and natural killer cell activity in family caregivers participating in a physical activity trial

Associations between psychological functioning and natural killer cell activity (NKA) were examined in 23 older (62.2 ± 7.5 years) family caregivers randomized to a moderate intensity four-month exercise program or to a wait-list control condition. At baseline, although NKA was related to anger-control (r = -.42; trend p < .06) and anger-out (r = .50; p < .03), it was not related to depression, anxiety, perceived stress, or caregiver burden. After controlling for baseline NKA, changes in anger-control explained 14 percent of the variance in NKA four months later. Decreases in anger-control predicted increases in NKA. Group assignment (exercise vs control) was unrelated to changes in NKA over the four-month period; however, the study was not powered to detect this effect. These results are consistent with reported relationships of anger expression with other physiological measures, and extend the importance of anger expression to immune functioning in older family caregivers.

Salubrious effects of oxytocin on social stress-induced deficits

Social relationships are a fundamental aspect of life, affecting social, psychological, physiological, and behavioral functions. While positive social interactions can attenuate stress and promote health, the social environment can also be a major source of stress when it includes social disruption, confrontation, isolation, or neglect. Social stress can impair the basal function and stress-induced activation of the hypothalamic-pituitary-adrenal (HPA) axis, impairing function of multiple biological systems and posing a risk to mental and physical health. In contrast, social support can ameliorate stress-induced physiological and immunological deficits, reducing the risk of subsequent psychological distress and improving an individual's overall well-being. For better clinical treatment of these physiological and mental pathologies, it is necessary to understand the regulatory mechanisms of stress-induced pathologies as well as determine the underlying biological mechanisms that regulate social buffering of the stress system. A number of ethologically relevant animal models of social stress and species that form strong adult social bonds have been utilized to study the etiology, treatment, and prevention of stress-related disorders. While undoubtedly a number of biological pathways contribute to the social buffering of the stress response, the convergence of evidence denotes the regulatory effects of oxytocin in facilitating social bond-promoting behaviors and their effect on the stress response. Thus, oxytocin may be perceived as a common regulatory element of the social environment, stress response, and stress-induced risks on mental and physical health. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior.

An occupational health study of emergency physicians in Japan: health assessment by immune variables (CD4, CD8, CD56, and NK cell activity) at the beginning of work

This study was conducted to evaluate the occupational health of Japanese physicians in emergency medicine. Subjects participating in this study were eighty-nine physicians working at 12 medical facilities (10 critical care emergency centers) in Japan. Participants were asked to complete a questionnaire of work conditions and to provide blood samples for immune variable measurements (CD4, CD8, CD56 and natural killer cell (NK cell) activity) before commencing their work. The data collected from seventy-four of 89 participating physicians were analyzed. The traditional work group comprised of 39 emergency physicians, who were significantly overworked compared to other two groups: the shift work group and the day work group. Among these three groups, no immune variable was significantly different except lymphocyte, number of CD4, and NK cell activity; and the NK cell activity of the shift work group was significantly lower than those of the traditional work group (p<0.01) and the day work group (p<0.01) in terms of Bonferroni's multiple comparison, probably due to circadian rhythm. It was indicated that NK cell activity was significantly lower in samples collected at night versus in the morning (OR=8.34, 95%CI: 1.95-35.6, p<0.01) through multiple logistic regression analyses. NK cell activity was significantly lower in individuals taking 0-3 days off per month, as compared to those taking 4 or more days off (OR=4.65, 95%CI: 1.27-17.0, p=0.02), according to multiple logistic regression analyses. Therefore, the low NK cell activity appears to have reflected the extent of fatigue arising from physicians' overwork. Overwork would have been a potential risk for the physicians' health, resulting in a lower quality of Japanese emergency medical services than that which could have been achieved otherwise. This study suggests that it would be better for the Japanese emergency physicians to take 4 or more days off per month for their health and the quality of their services.

Effect of dietary oils on lymphocyte immunological activity in psychologically stressed mice

Psychological stress has been shown to modulate immune functions. In this study, we investigated the effect of dietary oils (olive oil, soybean oil, and fish oil) on the social isolation stress-induced modulation of lymphocyte immunological activities in mice. In olive oil-fed, but not soybean oil- or fish oil-fed, mice, a 2-week isolation stress decreased the lymphocyte proliferative response, reduced the interferon-gamma and interleukin (IL)-10 secretions and increased the IL-4 secretion by lymphocytes. The isolation stress reduced the arachidonic acid content of lymphocytes markedly, moderately, and not at all in the olive oil-, soybean oil-, and fish oil-fed mice, respectively. In the olive oil-fed, but not soybean oil- or fish oil-fed, mice, the isolation stress up-regulated the expression level of mRNA for splenic heat-shock protein 70 and increased lymphocyte sensitivity to the antiproliferative effect of corticosterone. This is the first demonstration that effect of psychological stress on lymphocyte immunological activities can vary depending upon the dietary fatty acid composition.

Cytokines, stressors, and clinical depression: augmented adaptation responses underlie depression pathogenesis

By influencing the central nervous system, cytokines, which regulate immune function innately and adaptively, may play a key role in mediating depression-like neuro-behavioral changes. However, the similarity between cytokine and stressor-effects in animal models raises a question about the degree to which behavioral and neurochemical outcomes of cytokine challenge represent depressive disorder per se. The present review attempts to illustrate the degree of overlap between cytokines and stressors with respect to their effects on neurochemistry and behavior in animal models. The review also shows how short-term effects of cytokine exposure in typical animals may be discerned from characteristics that might otherwise be described as depression-like. By comparing outcomes of immune challenge in typical rodent strains (e.g., Sprague-Dawley [SD], Wistar) and an accepted animal model of depression (e.g., Fawn Hooded [FH] rodent strain), differences between short-term effects of cytokines and depression-like characteristics in rodents are demonstrated. Additionally, because it is known that preexisting vulnerability to depression may affect outcomes of immune challenge, we further compare immunological, biochemical and behavioral effects of cytokines between SD and FH rodent strains. Interestingly, the acute neurochemical and behavioral effects of the cytokine interleukin 1alpha (IL-1alpha) reveal stressor-like responses during behavioral habituation in both strains, though this appears to a stronger degree in FH animals. Further, the subacute response to IL-1alpha vastly differed between strains, indicating differences in adaptive mechanisms. Thus, stressor-like effects of immune challenge, particularly in FH animals, provide validation for recent "cross-sensitization" models of depression pathogenesis that incorporate immune factors.

Serum immunoglobulins and white blood cells status of drug addicts: influence of illicit drugs and sex habit

The aim of this study was to investigate the serum immunoglobulins and white blood cells status of drug addicts and to assess the extent of influence of drug habit and sexual practice on the immune components. The study was conducted among 253 male drug addicts and 100 non-addict controls of aged 18-45 years. An enzyme-linked immunosorbent assay (ELISA) was employed to analyse the serum immunoglobulin concentrations. White blood cells profile was estimated by counting 200 cells. Results showed a significant increase (p<0.03) of serum IgG, IgA and IgM in the drug addicts (6.93+/-1.53 g/l, 2.90+/-1.13 g/l and 1.72+/-0.73 g/l, respectively) compared to those in the cohort controls (6.52+/-1.05 g/l, 2.61+/-0.83 g/l and 1.52+/-0.59 g/l, respectively). A significant (p=0.00) decrease of peripheral lymphocytes (51.8+/-15.2 vs. 71.9+/-11.5) was noted in the drug addicts. Monocytes (8.3+/-4.9), neutrophils (128.2+/-18.9) and eosinophils (11.4+/-5.8) were found to be increased in the drug addicts against those in the controls (5.2+/-2.5, 113.2+/-13.0 and 9.6+/-5.8, respectively). Multiple drug abuse for longer period had resulted in a significant (p<0.05) decrease of serum immunoglobulins and lymphocytes. The longer period of addiction had also made a significant (p<0.05) decrease of eosinophils (p=0.05) and an increase of monocytes and neutrophils. Sex with multiple sexual partners had shown a significant (p<0.01) decrease of serum immunoglobulins and eosinophils.

Chronic stress in nonelderly caregivers: psychological, endocrine and immune implications

OBJECTIVE

This investigation examined whether the immune dysregulation that characterises elderly informal caregivers (e.g., spousal caregivers of dementia patients) extends to a younger caregiver population, specifically spousal carers of patients with multiple sclerosis (MS).

METHOD

MS spousal caregivers (n=41, mean age 43 years, 14 women, 27 men) and noncaregiving controls (n=62, mean age 33 years, 44 women, 18 men) were recruited. Psychological morbidity (i.e., self-reported stress, anxiety and depression), endocrine activity (i.e., salivary cortisol and DHEAs) and immunity (i.e., IgG and HAI responses to influenza vaccination and IFN-gamma and IL-4 levels) were assessed.

RESULTS AND CONCLUSIONS

MS caregivers and noncaregivers did not differ significantly in their IgG or HAI responses to influenza vaccination or in levels of IFN-gamma and IL-4. However, it remains unclear whether the "preserved" immune response of these younger caregivers was due to (1) an absence of immune senescence, (2) a relative absence of psychological morbidity, or both.

Dementia caregiving: recent research on negative health effects and the efficacy of caregiver interventions

Provision of care to an older adult with dementia is an important societal resource. This resource may also come at a high cost to informal caregivers, most of whom are family members. In this paper we provide an overview of recent research on dementia caregiving and caregiver interventions. First, we provide background information on the prevalence and costs of Alzheimer's disease and related disorders. Second, we describe the specific stressors and broader mental and physical health outcomes of dementia caregiving. Third, recent evidence of the efficacy of caregiver interventions for both caregiver and patient outcomes is reviewed. Throughout the paper, we describe promising new directions for future research in this area, including assessment and intervention with family caregivers of older patients with comorbid dementia and depression, and the focus on sleep disturbance as a critical health consequence of dementia caregiving.

Psychoneuroimmunology: psychological influences on immune function and health

This review focuses on human psychoneuroimmunology studies published in the past decade. Issues discussed include the routes through which psychological factors influence immune function, how a stressor's duration may influence the changes observed, individual difference variables, the ability of interventions to modulate immune function, and the health consequences of psychosocially mediated immune dysregulation. The importance of negative affect and supportive personal relationships are highlighted. Recent data suggest that immune dysregulation may be one core mechanism for a spectrum of conditions associated with aging, including cardiovascular disease, osteoporosis, arthritis, Type 2 diabetes, certain cancers, and frailty and functional decline; production of proinflammatory cytokines that influence these and other conditions can be stimulated directly by negative emotions and indirectly by prolonged infection.

Emotions, morbidity, and mortality: new perspectives from psychoneuroimmunology

Negative emotions can intensify a variety of health threats. We provide a broad framework relating negative emotions to a range of diseases whose onset and course may be influenced by the immune system; inflammation has been linked to a spectrum of conditions associated with aging, including cardiovascular disease, osteoporosis, arthritis, type 2 diabetes, certain cancers, Alzheimer's disease, frailty and functional decline, and periodontal disease. Production of proinflammatory cytokines that influence these and other conditions can be directly stimulated by negative emotions and stressful experiences. Additionally, negative emotions also contribute to prolonged infection and delayed wound healing, processes that fuel sustained proinflammatory cytokine production. Accordingly, we argue that distress-related immune dysregulation may be one core mechanism behind a large and diverse set of health risks associated with negative emotions. Resources such as close personal relationships that diminish negative emotions enhance health in part through their positive impact on immune and endocrine regulation.

Human lymphocyte growth hormone stimulates interferon gamma production and is inhibited by cortisol and norepinephrine

Lymphocyte growth hormone (L-GH) is distributed throughout the human immune system; however, its biologic role has not been defined. In order to clarify this issue, we determined if Candida, commonly used as a recall antigen, and IL-12, an important monocyte cytokine that stimulates the TH1 cytokine pathway, could stimulate L-GH mRNA synthesis in cultured human peripheral blood mononuclear cells (PBMCs). Both Candida and IL-12 produced significant (p<0.01) stimulation of L-GH mRNA synthesis and the TH1 cytokine, gamma interferon (IFN-gamma). These effects on IFN-gamma production were significantly (p<0.001) inhibited by a GH antagonist, suggesting that L-GH was acting by an autocrine or paracrine mechanism to enhance IFN-gamma production in these serum-free cultured cells. Concentrations of norepinephrine and cortisol achievable in humans during stress were able to significantly (p<0.001) decrease L-GH synthesis in the PBMCs. They also diminished IFN-gamma significantly (p<0.001), but not the TH2 cytokine, IL-10, in the supernatants of the cultured PBMLs. These studies suggest that L-GH plays a role in cellular immune function mediated via the TH-1 pathway.

Lymphocyte proliferation is associated with gender, caregiving, and psychosocial variables in older adults

We examined lymphocyte responses to mitogens [phytohemagglutinin (PHA), concanavalin A, pokeweed] in spouse caregivers of persons with Alzheimer's disease (n = 82; mean age = 69.4) and noncaregiver spouses (n = 83) group matched on age and gender. Data were collected at study entry (T1) and 15-18 months later (T2). In men (n = 52), a depressed mood factor was negatively related to all mitogen responses at T1 and PHA at T2. Loneliness was the most important variable in the depressed mood factor. No relationships occurred in women (n = 113). At T2 an anger expression factor (anger-out--anger-control) was negatively related to all mitogen responses in caregivers. Anger-out was the most important variable for anger expression. Depressed mood at T1 predicted residualized changes in PHA at T2 in men. In conclusion, men with higher depressed mood and caregivers with higher anger expression may be at risk for lower proliferation responses.

Depressed mood, physician-rated prognosis, and comorbidity as independent predictors of 1-year mortality in consecutive medical inpatients

OBJECTIVE

To determine the independent effects of depressed mood and markers of medical disease severity on mortality in consecutive medical inpatients.

METHODS

Consecutive general medical inpatients were asked to complete the Hospital Anxiety and Depression Scale (HADS) at admission. Prognostic indicators were obtained from patients' records and physicians' ratings. The study endpoint was mortality from all causes at 1 year.

RESULTS

The baseline assessment was completed by 575 patients (87.7%). Survival data were available for 572 of these (86 deaths). HADS depression scores and several physical risk indicators predicted mortality. In multivariate analyses, physicians' rating of prognosis was the best predictor of mortality [adjusted odds ratio (OR) 3.6; 95% confidence interval (CI), 2.5--5.4]. Other independent predictors included a principal diagnosis of hemato-oncological disease, comorbidity scores, and HADS depression (adjusted OR 1.75; 95% CI, 1.10--2.79).

CONCLUSION

Our data demonstrate an independent prognostic effect of depressed mood on mortality in general medical inpatients. Screening for depression may improve risk stratification in these patients over and above that obtained by routinely available physical parameters and physicians' clinical judgement.

Immune, endocrine, and psychological responses in civilians displaced by war

OBJECTIVES

The objectives of this study were to assess the influence of trauma caused by forced expulsion from home in a war-ravaged region on the psychological, hormonal, and immune responses in displaced persons and to analyze the relationships between psychometric, hormonal, and immunologic variables.

METHODS

Participants were 20 displaced and 14 control women. Psychosomatic response was evaluated using the COR-NEX2 test. Serum concentrations of cortisol, prolactin, endorphin, thyroxine, and triiodothyronine were measured by radioimmunoassay. Immunophenotyping and lymphocyte proliferation were determined by flow cytometry, and phagocyte functions (i.e., ingestion and antibody-dependent cytotoxicity) against 51Cr-labeled sheep red blood cells were assessed through radioactivity uptake and release, respectively.

RESULTS

In comparison with control women, displaced women had higher COR-NEX2 test scores; higher serum cortisol, prolactin, and endorphin levels; an increase in activated phenotype within all three measured cell populations (i.e., B, T, and natural killer cells); as well as an enhanced proportion of proliferating lymphocytes in freshly isolated samples. However, the phytohemagglutinin-stimulated proliferative response, estimated as the stimulation index, was lower in displaced women. A complex pattern of relations between psychological, hormonal, and immune responses was observed.

CONCLUSIONS

Chronic psychological stress elicited multiple, predominantly stimulatory influences on immune functions.

Nonradioactive techniques for measurement of in vitro T-cell proliferation: alternatives to the [(3)H]thymidine incorporation assay

T-cell proliferation is an important in vitro parameter of in vivo immune function and has been used as a prognostic marker of human immunodeficiency virus type 1 (HIV-1) disease progression. The proliferative capacity of T cells in response to various stimuli is commonly determined by a radioactive assay based on incorporation of [(3)H]thymidine ([(3)H]TdR) into newly generated DNA. In order to assess techniques for application in laboratories where radioactive facilities are not present, two alternative methods were tested and compared to the [(3)H]TdR assay as a "gold standard." As an alternative, T-cell proliferation was measured by flow cytometric assessment of CD38 expression on T cells and by an enzyme-linked immunosorbent assay (ELISA) based on bromo-2'-deoxyuridine (BrdU) incorporation. Peripheral blood mononuclear cells (PBMCs), either in whole blood or Ficoll-Isopaque separated, from a total of 26 HIV-1-positive and 18 HIV-1-negative Dutch individuals were stimulated with CD3 monoclonal antibody (MAb) alone, a combination of CD3 and CD28 MAbs, or phytohemagglutinin. BrdU incorporation after 3 days of stimulation with a combination of CD3 and CD28 MAbs correlated excellently with the [(3)H]TdR incorporation in both study groups (HIV-1 positives, r = 0.96; HIV-1 negatives, r = 0.83). A significant correlation of absolute numbers of T cells expressing CD38 with [(3)H]TdR incorporation, both in HIV-1-positive (r = 0.96) and HIV-1-negative (r = 0.84) individuals, was also observed under these conditions. The results of this study indicate that determination of both the number of CD38-positive T cells and BrdU incorporation can be used as alternative techniques to measure the in vitro T-cell proliferative capacity. The measurement of CD38 expression on T cells provides the additional possibility to further characterize the proliferating T-cell subsets for expression of other surface markers.

Chronic stress in caregivers of dementia patients is associated with reduced lymphocyte sensitivity to glucocorticoids

Caring for the chronically ill is associated with chronic distress. In view of the adverse effects of distress on cellular immune function, such distress may have implications for health. Indeed, it has been proposed that the hypothalamic-pituitary-adrenal (HPA) axis is a potential psychobiological mediator of these effects. In this study, we observed that elderly caregivers experienced greater distress and increased salivary cortisol than non-caregivers. In addition, caregivers had blunted mitogen-induced lymphocyte proliferation, lower mitogen-induced IL-2 production, and reduced lymphocyte sensitivity to glucocorticoids. These results indicate that chronic distress is associated with impaired cell-mediated immunity which is, in turn, associated with elevated basal steroid levels and altered steroid immunoregulation at the level of the lymphocyte.

The measurement of stress-related immune dysfunction in psychoneuroimmunology

In recent years there has been a dramatic increase in research dedicated to the psycho-behavioural modulation of immune function, i.e. the field of Psychoneuroimmunology (PNI). This has led, necessarily, to the use of several in vitro and in vivo techniques in attempts to delineate the relationship between these two phenomena. However, since the field's inception, considerable uncertainty has existed over the significance of the immune outcomes detected and this has been compounded by the equivocal nature of some of the published data. A great deal of this uncertainty could, however, be overcome if a clearer understanding was achieved on the advantages and limitations conferred by the manifold immune assays described in the literature. This would, in turn, encourage their more appropriate use within PNI. Hence, in this review we describe the rationale behind, and offer an evaluation of, some of the more frequently used in vitro and in vivo immunological and virological techniques. We hope that a clear understanding of the rationale behind such assays and their inherent advantages and limitations will inform the discussion of the significance of stress-related immune impairment.

Chronic stress in dogs subjected to social and spatial restriction. II. Hormonal and immunological responses

Two groups of beagles, accustomed to spacious group housing, were subjected to social and spatial restriction and studied for manifestations of chronic stress with a time interval of 7 weeks between the groups. The change from outside group housing (the control period) to individual housing in small indoor kennels resulted in sustained decreases in urinary adrenaline/creatinine and noradrenaline/creatinine ratios for the total group. Urinary dopamine/creatinine and noradrenaline/adrenaline ratios were statistically unaffected. Socially and spatially restricted dogs that had experienced pleasant weather during the control period showed (a) increased salivary and urinary cortisol concentrations, (b) a diminished responsiveness of the pituitary-adrenal axis to a sudden sound blast or exogenous CRH, (c) intact plasma ACTH and cortisol suppressions after dexamethasone administration, and (d) increased concanavalin A induced lymphocyte proliferations. When social and spatial restriction was preceded by a control period during which the weather was bad, these physiological responses were either augmented (lymphocyte proliferation), or offset (salivary and urinary cortisol), or directed oppositely (CRH-induced ACTH and cortisol responses). Together with the previously presented behavioral observations, these data suggest that bad weather conditions during spacious outdoor group housing induced early stress that attenuated the negative appraisal of the subsequent period of social and spatial restriction. In comparison to male dogs, bitches showed increased HPA responses to a sound blast or exogenous CRH. Their increased attenuations of the ACTH and cortisol responses to CRH after 5 weeks of restricted housing indicates that bitches are not only more susceptible to acute stress, but also to chronic housing stress. It is concluded that the quality of circumstances preceding a period of affected well-being determines the magnitude and even the direction of the behavioral and physiological stress responses. Basal salivary and urinary cortisol measurements are useful for the assessment of chronic stress, and of poor welfare in dogs. The use of urinary catecholamine, peripheral leucocyte, and lymphocyte proliferation measures requires further investigation.

Immune dysfunction associated with chronic professional stress in nurses

The relationship between chronic professional stress in nurses and immunity as well as the possible impact of psychopathology upon this relationship have been examined. Sixty subjects were selected on the basis of high/low scores on professional stress and psychopathology. Chronic professional stress appeared to be associated with immune dysfunction including signs of immune activation (increased numbers of cells expressing the interleukin-2 receptor, especially CD4+CD25+ cells) and possibly immune suppression (decrease in percentage of natural killer cells). The increase in activation markers, CD3+CD16CD56+ cells and serum neopterin was most pronounced in the group with high stress/low psychopathology whereas the decrease in CD8+CD11b+ cells was most pronounced in the group with high stress/high psychopathology. It is hypothesized that in the presence of chronic stress distinct psychological mechanisms are associated with specific immune dysfunctions.

Stress, depression and immunity: the role of defense and coping styles

It is by now widely recognized that acute and chronic stress have an impact on the immune system. Acute stress may have a stimulating effect on the immune system, while in the case of chronic stress--and in particular in depression--the immune system may be down-regulated. However, there is considerable individual variability in the immune response to stress. This seems to a large extent to be determined by the subject's way of dealing with stress. The perception and evaluation of a stressor and the specific ways of stress coping may in different ways be related to various aspects of the stress response: sympathetic nervous system (SNS) activation and activation of the hypothalamic-pituitary-adrenal (HPA) axis, both systems affecting the immune system. Prolonged exposure to stressors or to severe life stresses may outweigh the person's coping resources leading to feelings of depression. The affective changes with the accompanying changes in the HPA axis are one of the hypothesized mechanisms underlying the immune changes in depression. It should be noted that the relationship between depression and immunity is affected by several other factors, such as gender and age and other personal resources. Increasing the subject's abilities to cope with stress and to reduce the negative affect by psychological interventions may on the other hand have a beneficial effect on the immune system.

Diagnostic groups and depressed mood as predictors of 22-month mortality in medical inpatients

OBJECTIVE

While depression has been found to predict mortality in acute myocardial infarction, results from many other groups of medical patients are inconclusive. It is, therefore, unclear whether depression also predicts mortality in the typical mixed patient populations treated on medical hospital wards and whether an increased risk can be identified by means of patients' self ratings of depression.

METHOD

The Hospital Anxiety and Depression scale was used as a routine screening tool in consecutive admissions to the general medical wards of a university hospital. The official survival data were obtained 22 months later. For all 454 patients who completed the screening questionnaire, complete survival data were available.

RESULTS

High depression scores significantly predicted mortality in univariate comparisons (odds ratio 3.2; 95% CI 1.9-5.5) and in multivariate Cox regression analyses controlling for demographic and medical baseline variables (multivariate odds ratio 1.9; 95% CI 1.2-3.1; p < .01). Other significant predictors in the multivariate model were having a principal diagnosis of hematological disease or cancer, and older age. Disability, as assessed by nurses' ratings, and gender were not related to mortality. Subgroup analyses showed that the effect of depression scores was greatest in cardiopulmonary patients, but there was also a uniform trend toward higher mortality in depressed patients with other diagnoses.

CONCLUSION

Depressed mood is an independent risk factor for all-cause mortality in medical inpatients. Identifying patients at risk does not require formal psychiatric diagnoses, but can be achieved by means of a short, routinely administered self-rating questionnaire.

CD4 and CD8 counts are associated with interactions of gender and psychosocial stress

OBJECTIVE

This study examined relationships of gender, psychosocial stress/distress (caregiving, hassles, depressed mood), and the relative percentage and absolute cell counts of CD4 and CD8 cells in two samples of older adults (mean age = 69.4)--spouse caregivers of persons with Alzheimer's disease (N = 78) and age- and gender-matched spouses of nondemented controls (N = 72).

METHODS

Counts and percentages of CD4 and CD8 cells and psychosocial variables were assessed twice (Time 1, Time 2) over a 15- to 18-month period. Several covariates were examined in the analyses, including body mass index (BMI), medication use, alcohol use, exercise, and illness history.

RESULTS

Caregiver men had fewer CD4 cell counts at Times 1 and 2 than did control men (p < .05). At Times 1 and 2, both CD8 cell counts and percentages were positively associated with hassles in men (p < .05), but not in women. Although interactions of hassles and gender were present for CD8 percentages at both times, interactions and main effects were not present for CD4 percentages at either time. When the ratio of CD4 to CD8 levels was analyzed, hassles by gender interactions were present at both Times 1 and 2-hassles were negatively associated with the CD4/CD8 ratio in men (p < .05), but unrelated in women. From Time 1 to Time 2, change analyses showed that increases in hassles scores were associated with decreases in CD4 counts (p < .05), whereas increases in Hamilton Depression Scores were related to increases in both CD8 counts and percentages (p < .05).

CONCLUSION

Caregiver status, hassles, and depressed mood had cross-sectional and/or longitudinal associations with CD4 and CD8 counts, but such relationships occurred primarily in men. Moreover, absolute cell counts were more related to psychosocial factors than were percentages.

Research on physiological and physical concomitants of caregiving: where do we go from here?

This article discusses the current state of research on the physiological and physical concomitants of caregiving. We offer recommendations about theoretical, empirical, and treatment issues that researchers should consider in future investigations. Important theoretical issues include specifying acute and chronic stress in caregiving research. Empirical issues include sample selection, home versus clinic assessments, the use of experimental probes, moderating and mediating variables, and measurement issues (problems with self-report of health, medical records, physical exams, and lab assessments). Finally, we note that investigators should use this newfound knowledge to target interventions to specific subsets of vulnerable caregivers. In this way, basic research into caregiving, as a model of chronic human stress, can provide more focused approaches to benefit both caregivers and patients.

The influence of psychological stress on the immune response to vaccines

We compared virus-specific antibody and T-cell responses to influenza virus vaccination in 32 caregivers of Alzheimer's disease (AD) patients and matched control subjects. Caregivers showed a poorer antibody response and virus-specific T-cell response following vaccination compared to the control subjects as measured by fourfold increases in antibody titers to the vaccine and lower levels of virus-induced IL-2 levels in vitro. We performed a second study in which forty-eight medical students were inoculated with a series of three injections of the hepatitis-B (HEP-B) vaccine to coincide with the third day of three, three-day examination blocks. Twelve of the 48 medical students seroconverted after the first injection; these students were characterized by falling into the lower stressed/lower anxiety group of students. Students who reported greater social support and lower anxiety and stress demonstrated a higher antibody response to the vaccine and a more vigorous T-cell response to HEP-B surface antigen at the end of the third examination experience. The differences in antibody and T-cell responses to HEP-B and influenza virus vaccinations provide a demonstration of how stress may be able to alter both the cellular and humoral immune responses to vaccines and novel pathogens in both younger and older adults.

Study of human neurovegetative and hematologic effects of environmental low-frequency (50-Hz) electromagnetic fields produced by transformers

A survey of neurovegetative and hematologic disorders was conducted in a population (n = 13) exposed occupationally to environmental electromagnetic fields; the population was matched with 13 control subjects. The exposed subjects worked at least 8 h/d for 1-5 y in premises located above transformers and high-tension cables, and the subjects were submitted to low-frequency electromagnetic fields (i.e., 50 Hz) of 0.2 microT-6.6 microT. The subjects were matched with respect to socioeconomic category, sex, and age with a control population of subjects that worked in premises outside of the immediate vicinity of transformers or high-tension cables. The exposed population had a significant increase in degree of certain neurovegetative disorders (i.e., physical fatigue, psychical asthenia, lipothymia, decreased libido, melancholy, depressive tendency, and irritability). In addition, the population experienced a significant fall in total lymphocytes and CD4, CD3, and CD2 lymphocytes, as well as a rise in NK cells. Leukopenia and neutropenia were also observed in two persons permanently exposed to doses of 1.2-6.6 microT. The disorders disappeared when exposure stopped, and they reappeared on reexposure.

Mind-body therapies for primary care physicians

Evidence is accumulating that mental and emotional processes can affect disease states. Mind-body therapies are effective adjuncts to conventional medical treatments, and they are easy to teach and learn. This article offers a review of relevant literature and introduces several mind-body techniques.

Searching for the biological pathways between stress and health

Population-based, person-specific health surveys, with concomitant biological measures, should provide important information about the processes by which socioeconomic and psychosocial factors embed themselves in human health. Questionnaire responses allow for assessment of the perceived psychosocial environment, but biological measurements will measure the status of the psychoneuroimmunology/ psychoneuroendocrinology (PNI/PNE) pathways and may allow us to identify people who have "adapted" to their stress because of experience, expectations, stoicism, etc. This review sets criteria to evaluate potential physiological markers of chronic stress. Because population health surveys involve a massive number of samples, special consideration must be given to the laboratory analysis method and transportation time of the markers chosen. We reviewed five areas: glycosylated proteins, the immune system, hemostasis peripheral benzodiazepine receptors, and the waist-hip ratio.

Impairment of non-specific immunity in patients in persistent vegetative state

In fourteen patients in persistent vegetative state (PVS) immune responsiveness was investigated. In particular, we studied the relationship between brain lesions following traumatic injury and immune system. In this respect, phagocytosis and killing of Candida albicans by polymorphonuclear cells (PMN) and monocytes were tested. In addition serum levels of Interferon-gamma (IFN-gamma) were evaluated. The patients come out from PVS by 3-4 month were used as control group. Data shown a profound impairement of phagocytosis and killing of monocytes and low serum levels of IFN gamma when compared with normal values. Taken together, these findings suggest that brain lesions, may affect non-specific immune response.

The immune system and major depression

This paper reviews research literature on the links between human immune functioning and mood disorders. It summarizes the initial steps of this fledgling research area since its inception in the late 1970s, and outlines a range of studies that are needed to increase our neuroimmunological sophistication. Future investigations will require greater specificity in several interrelated realms of inquiry: diagnostic, epidemiologic, and physiologic. In particular, this paper highlights basic physiological studies needed in both neurophysiology and immunology to provide a foundation for meaningful examination of their interface. Among the areas that require more specific investigation in both immunologic and mood disorders research is that of temporal organization. Just as psychiatric researchers have begun to scrutinize temporal cycles of mood, behavior, and neurophysiology, so too exploration of immune functioning must take into account predictable temporal cycles such as circadian and ultradian rhythms, as they shape responses to unanticipated external perturbations. Clarification of the temporal dimension will add significantly to our analysis of the links between immune functioning and mood disorders. The basic science of psychoneuroimmunology continues to mature, bringing new discoveries and revealing hitherto unknown mechanisms and interactions. This is a field of study in many ways still on the frontier, and explication of the long suspected links between mood disorders and immune functioning continues to beckon.