Dementia severity of the care receiver predicts procoagulant response in Alzheimer caregivers

A Literature Review on the Burden of Alzheimer's Disease on Care Partners

BACKGROUND

Many individuals with Alzheimer's disease (AD) are dependent on nonprofessional care partners. Providing informal care can result in emotional, physical, and financial burdens; however, there is a need for a better understanding of the impact of AD on care partners to support the clinical and economic assessment of potential new treatments.

OBJECTIVE

We conducted a literature review to evaluate the burden experienced by care partners of individuals with AD.

METHODS

Electronic screening and supplementary searches identified studies published from 2011 to 2022 describing the association between AD and the quality of life (QoL) and physical health of care partners, and the economic or financial burden of AD.

RESULTS

Following electronic screening, 62, 25, and 39 studies were included on care partner burden, cost, and healthcare resource use in AD, respectively. Supplementary searches identified an additional 32 studies, resulting in 149 unique studies. These studies showed that care partners of individuals with AD report moderate to severe burden. Higher burden and lower QoL were observed in those caring for individuals with more severe AD. Care partners of individuals with AD experience higher burden, lower QoL, and higher levels of stress, depression, and anxiety than those without caring responsibilities. Informal care costs increased with AD severity and accounted for the greatest proportion of overall societal cost.

CONCLUSIONS

Care partners of individuals with AD experience emotional and economic burden, which increases with AD severity. These impacts should be quantified comprehensively in future studies and captured in economic evaluations of AD interventions.

Impact of Alzheimer's Dementia on Caregivers and Quality Improvement through Art and Music Therapy

Dementia is a general term for a series of medical conditions that affect the brain and evolve progressively. According to the literature, there are over 200 subtypes and causes of dementia, with Alzheimer's disease (AD) being the most common in elderly people. AD is an irreversible progressive neurodegenerative condition that leads to a decline in mental function, enough to disrupt daily life. Thinking skills slowly deteriorate, which, in advanced stages, makes it impossible to perform simple tasks. Besides the change in the quality of life of AD patients and their families, there is a considerable alteration in the quality of life of their caregivers, whose health can be negatively affected by the development of mental and somatic disorders. This article reviews the literature in order to reveal the benefits of applying non-pharmacological interventions such as music and art therapy to improve quality of life. This article also aims to shed light on the impact of this disease on the caregiver's life. Music and art therapy have produced reliable results in the treatment of patients with AD, and the best effects are related to increased socialization and the maintenance of social status.

Clinical Psychological Figures in Healthcare Professionals: Resilience and Maladjustment as the "Cost of Care"

Background: The health professionals are involved in the paths of care for patients with different medical conditions. Their life is frequently characterized by psychopathological outcomes so that it is possible to identify consistent burdens. Besides the possibility to develop pathological outcomes, some protective factors such as resilience play a fundamental role in facilitating the adaptation process and the management of maladaptive patterns. Personal characteristics and specific indexes such as burdens and resilience are essential variables useful to study in-depth ongoing conditions and possible interventions. The study was aimed at highlighting the presence and the relations among factors as personal variables, burdens, and resilience, to understand health professionals' specific structure and functions.

Methods: The observation group was composed of 210 participants, 55 males (26.2%), and 155 females (73.8%), aged from 18 to 30 years old with a mean age of 25.92 years old (SD = 3.33). The study considered personal characteristics of the subjects, such as age, gender, years of study, days of work per week, hours of work per week, and years of work. Our study had been conducted with the use of measures related to burdens (Caregivers Burden Inventory) and resilience (Resilience Scale for Adults).

Results: The performed analyses consisted of descriptive statistics, correlations, and regressions among the considered variables. Several significant correlations emerged among personal characteristics, CBI, and RSA variables. Specifically, age and work commitment indexes appeared to be significantly related to the development of burdens, differently from the years of study. Significant correlations emerged among personal and RSA variables, indicating precise directions for both domains. Age and gender were identified as predictors to perform multivariate regression analyses concerning CBI factors. Significant dependence relations emerged with reference to all CBI variables.

Conclusion: Pathological outcomes and resilience factors represent two sides of the health professionals' experiences, also known as “invisible patients.” Greater knowledge about present conditions and future possibilities is a well-known need in literature so that the current analyses considered fundamental factors. In line with state of the art, future studies are needed in order to deepen elusive phenomena underlying maladjustment.

Long-term caregiving is associated with impaired cardiovagal baroreflex

OBJECTIVE

Caregiving stress is associated with increased risk of cardiovascular disease (CVD). Inability to adequately regulate blood pressure is a possible underlying mechanism explaining this risk. We examined the relationship between length of caregiving and cardiovagal baroreflex sensitivity (cBRS) to better understand the link between caregiving and CVD risk.

METHODS

A total of 146 elderly individuals (≥55years) participated in this study, of whom 96 were providing in-home care to a spouse with dementia and 50 were healthy controls married to a non-demented spouse (i.e., non-caregivers). Among the caregivers, 56 were short-term caregivers (caring<4years) and 40 were long-term caregivers (caring≥4years). A multiple linear regression model, with contrast codes comparing short and long-term caregivers with non-caregivers was used to understand relationships between chronic caregiving and cBRS.

RESULTS

After controlling for relevant demographic and health characteristics, mean±SE log transformed cBRS for non-caregivers was 0.971±0.029. Relative to non-caregivers, the long-term caregivers had significantly impaired cBRS (0.860±0.033; p=0.013). However, mean cBRS for short-term caregivers did not significant differ from non-caregivers (0.911±0.028; p=0.144).

CONCLUSION

These results suggest that long-term caregiving stress is associated with an impaired cBRS. Accumulation of stress from years of caregiving could result in worse cBRS function, which could be a mechanistic explanation for the correlation between caregiving stress and the increased risk of CVD.

The Role of Biomarkers in Research on Caregivers for Cancer Patients: A Scoping Review

BACKGROUND

Biomarkers can be used as prognostic, predictive, or monitoring indicators of an associated outcome. The purpose of this review was to provide a comprehensive summary of the research examining the use of biomarkers as surrogate end points for clinical outcomes in family caregivers for cancer patients, identify gaps, and make recommendations for future research.

METHODS

A scoping review, a process of mapping the existing literature, was conducted. Studies comparing biomarkers across caregivers and controls and/or examining relationships between biomarkers and psychological health were reviewed.

RESULTS

The studies ( N = 18) of caregivers for cancer patients who were identified used biomarkers to predict outcomes ( n = 13) and to monitor the efficacy of interventions ( n = 6). Biomarkers were divided into two categories based on physiological systems involved: (1) neuroendocrine function (sympathetic-adrenal-medullary axis activity, hypothalamic-pituitary-adrenal axis activity) and (2) immune function. Predictive biomarkers were sensitive to differences between caregivers and controls. The biomarkers were used to evaluate outcomes frequently associated with stress, depression, and anxiety. Cortisol was the biomarker most commonly measured to monitor the efficacy of interventions.

DISCUSSION

Biomarkers are most commonly incorporated into caregiver studies to predict group membership and psychological health. Neuroendocrine biomarkers, specifically cortisol, are most frequently assessed. Future research should include biomarkers of other physiologic functions (e.g., cardiovascular function, cognitive dysfunction, and cell aging) and those that serve as multisystem indicators. Expanding the scientific study of biomarkers will contribute to our understanding of the mechanisms through which stress may influence caregiver health.

Chronic stress is associated with reduced circulating hematopoietic progenitor cell number: A maternal caregiving model

BACKGROUND

Chronic psychological stress is a risk factor for cardiovascular disease and mortality. Circulating hematopoietic progenitor cells (CPCs) maintain vascular homeostasis, correlate with preclinical atherosclerosis, and prospectively predict cardiovascular events. We hypothesize that (1) chronic caregiving stress is related to reduced CPC number, and (2) this may be explained in part by negative interactions within the family.

METHODS

We investigated levels of stress and CPCs in 68 healthy mothers - 31 of these had children with an autism spectrum disorder (M-ASD) and 37 had neurotypical children (M-NT). Participants provided fasting blood samples, and CD45⁺CD34⁺KDR⁺ and CD45⁺CD133⁺KDR⁺ CPCs were assayed by flow cytometry. We averaged the blom-transformed scores of both CPCs to create one index. Participants completed the perceived stress scale (PSS), the inventory for depressive symptoms (IDS), and reported on daily interactions with their children and partners, averaged over 7 nights.

RESULTS

M-ASD exhibited lower CPCs than M-NT (Cohen's d=0.83; p⩽0.01), controlling for age, BMI, and physical activity. Across the whole sample, positive interactions were related to higher CPCs, and negative interactions to lower CPCs (allp's<0.05). The adverse effects of group on CPCs were significantly mediated through negative interactions with the child (indirect β=-0.24, p⩽0.01). In the full model, greater age (β=-0.19, p=0.04), BMI (β=-0.18, p=0.04), and negative interactions with the child (β=-0.33, p<0.01) were independently associated with lower CPCs. M-ASD had a less healthy lipid profile (total cholesterol/HDL), which in turn, was associated with lower CPCs.

CONCLUSIONS

Chronic stress adversely impacts CPC number, an early-stage biomarker that predicts subclinical atherosclerosis and future CVD events, independent of traditional cardiovascular risk factors and inflammatory factors. Among maternal caregivers, child-related interpersonal stress appears to be a key psychological predictor of stress-related CVD risk.

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.

The Trier Social Stress Test: Principles and practice

Researchers interested in the neurobiology of the acute stress response in humans require a valid and reliable acute stressor that can be used under experimental conditions. The Trier Social Stress Test (TSST) provides such a testing platform. It induces stress by requiring participants to make an interview-style presentation, followed by a surprise mental arithmetic test, in front of an interview panel who do not provide feedback or encouragement. In this review, we outline the methodology of the TSST, and discuss key findings under conditions of health and stress-related disorder. The TSST has unveiled differences in males and females, as well as different age groups, in their neurobiological response to acute stress. The TSST has also deepened our understanding of how genotype may moderate the cognitive neurobiology of acute stress, and exciting new inroads have been made in understanding epigenetic contributions to the biological regulation of the acute stress response using the TSST. A number of innovative adaptations have been developed which allow for the TSST to be used in group settings, with children, in combination with brain imaging, and with virtual committees. Future applications may incorporate the emerging links between the gut microbiome and the stress response. Future research should also maximise use of behavioural data generated by the TSST. Alternative acute stress paradigms may have utility over the TSST in certain situations, such as those that require repeat testing. Nonetheless, we expect that the TSST remains the gold standard for examining the cognitive neurobiology of acute stress in humans.

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The TSST is the human experimental gold standard for evaluating the neurobiology of acute stress.

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The HPA axis response to the TSST is higher in males and lower in older adults.

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Genotype and epigenetic factors moderate the neurobiological response to the TSST.

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Multiple adaptations of the TSST are available for different testing contexts.

The Effects of Mindfulness-Based Stress Reduction for Family Caregivers: Systematic Review

Caring for patients with various conditions is demanding and stressful and can have a negative impact on both physical and psychological health. This paper reports a systematic review and critical appraisal of the evidence on the effectiveness of mindfulness-based stress reduction for the family caregivers of patients with various conditions. There were improvements in the self-rated psychological symptoms, such as stress, depression, anxiety and mindfulness. To conclude, mindfulness-based stress reduction, as a safe and transportable approach, has potential to improve the psychological symptoms in the caregivers of patients with various conditions.

Caregiver burden and coping strategies in caregivers of patients with Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) causes considerable distress in caregivers who are continuously required to deal with requests from patients. Coping strategies play a fundamental role in modulating the psychologic impact of the disease, although their role is still debated. The present study aims to evaluate the burden and anxiety experienced by caregivers, the effectiveness of adopted coping strategies, and their relationships with burden and anxiety.

METHODS

Eighty-six caregivers received the Caregiver Burden Inventory (CBI) and the State-Trait Anxiety Inventory (STAI Y-1 and Y-2). The coping strategies were assessed by means of the Coping Inventory for Stressful Situations (CISS), according to the model proposed by Endler and Parker in 1990.

RESULTS

The CBI scores (overall and single sections) were extremely high and correlated with dementia severity. Women, as well as older caregivers, showed higher scores. The trait anxiety (STAI-Y-2) correlated with the CBI overall score. The CISS showed that caregivers mainly adopted task-focused strategies. Women mainly adopted emotion-focused strategies and this style was related to a higher level of distress.

CONCLUSION

AD is associated with high distress among caregivers. The burden strongly correlates with dementia severity and is higher in women and in elderly subjects. Chronic anxiety affects caregivers who mainly rely on emotion-oriented coping strategies. The findings suggest providing support to families of patients with AD through tailored strategies aimed to reshape the dysfunctional coping styles.

Mindfulness-based stress reduction for family caregivers: a randomized controlled trial

PURPOSE

Caring for a family member with dementia is associated with chronic stress, which can have significant deleterious effects on caregivers. The purpose of the Balance Study was to compare a mindfulness-based stress reduction (MBSR) intervention to a community caregiver education and support (CCES) intervention for family caregivers of people with dementia.

DESIGN AND METHODS

We randomly assigned 78 family caregivers to an MBSR or a CCES intervention, matched for time and attention. Study participants attended 8 weekly intervention sessions and participated in home-based practice. Surveys were completed at baseline, postintervention, and at 6 months. Participants were 32- to 82-year-old predominately non-Hispanic White women caring for a parent with dementia.

RESULTS

MBSR was more effective at improving overall mental health, reducing stress, and decreasing depression than CCES. Both interventions improved caregiver mental health and were similarly effective at improving anxiety, social support, and burden.

IMPLICATIONS

MBSR could reduce stress and improve mental health in caregivers of family members with dementia residing in the community.

Effect of Alzheimer caregiving on circulating levels of C-reactive protein and other biomarkers relevant to cardiovascular disease risk: a longitudinal study

BACKGROUND

Providing care to a spouse with Alzheimer's disease (AD) may contribute to cardiovascular disease (CVD). The acute phase reactant C-reactive protein (CRP) is a well-established biomarker of an increased CVD risk.

OBJECTIVE

To investigate the hypothesis that dementia caregiving is associated with elevated circulating levels of CRP and possibly other biomarkers of CVD risk.

METHODS

We examined 118 elderly spousal Alzheimer caregivers and 51 noncaregiving controls about once a year for up to 3 years. Random regression models with fixed and time-variant effects for a range of covariates known to affect biomarker levels were used to evaluate changes in CRP and in 12 additional measures of inflammation, cellular adhesion, endothelial function, and hemostasis in relation to caregiving status, years of caregiving, and major transitions in the caregiving situation.

RESULTS

During the study period, longer duration of caregiving was associated with elevated CRP levels (p = 0.040) and caregivers showed greater tumor necrosis factor (TNF)-α levels than controls (p = 0.048). Additionally, 3 months after the death of the AD spouse, caregivers showed a significant drop in CRP levels (p = 0.003) and levels of soluble intercellular adhesion molecule (sICAM)-1 (p = 0.008).

CONCLUSION

Duration of caregiving and being a caregiver per se were both associated with chronic low-grade inflammation as indicated by elevated CRP and TNF-α levels, respectively. Conversely, death of the AD spouse was associated with lower CRP and sICAM-1 levels. The findings indicate that chronic caregiving of those with dementia may result in increased inflammation and, thereby, possibly increased CVD risk.

Effects of Alzheimer caregiving on allostatic load

This study aimed to determine if Alzheimer caregivers have increased allostatic load compared to non-caregivers. Potential psychological moderators (mastery, depression, and role overload) of the relationship between caregiving status and allostatic load were also explored. Eighty-seven caregivers and 43 non-caregivers underwent biological assessment of allostatic load and psychological assessments. Caregivers had significantly higher allostatic load compared to non-caregivers ( p < .05). Mastery, but not depression or overload, moderated the relationship between caregiving status and allostatic load. In conclusion, allostatic load may represent a link explaining how stress translates to downstream pathology, but more work is necessary to understand the role of psychological factors.

Association between chronic caregiving stress and impaired endothelial function in the elderly

OBJECTIVES

We examined the relationship between chronic caregiving stress and endothelial function.

BACKGROUND

Evidence suggests that caregiving stress is associated with pathophysiologic processes related to atherosclerosis. Endothelial dysfunction is a possible underlying mechanism explaining the relationship between caregiving stress and cardiovascular morbidity. We investigated the relationship between chronic caregiving stress and endothelial dysfunction assessed by reactive hyperemia-induced flow-mediated dilation (FMD).

METHODS

Seventy-eight elderly individuals participated in the study. Fifty-five were providing in-home care to a spouse with Alzheimer's disease, and 23 were married and living with a healthy, nondemented spouse. Analysis of covariance was used to examine the relationships between advancing dementia severity (Clinical Dementia Rating scores) and FMD and nitroglycerin-induced vasodilation of the brachial artery. Multiple linear regression was used to examine the relationship between years of caregiving and FMD.

RESULTS

Clinical Dementia Rating scale scores were significantly related to FMD (p = 0.033), with participants caring for a spouse with moderate to severe dementia showing significantly worse FMD than those caring for a spouse with mild dementia (p = 0.028) and noncaregivers (p = 0.032). Within the caregiver sample, the number of years of caregiving was significantly related to FMD (r = -0.465, p < 0.001).

CONCLUSIONS

These results suggest that the chronic stress of caregiving is associated with impaired endothelial function, which may be a potential mechanistic link to the observed increased risk of cardiovascular disease in elderly caregivers.

Problem behavior of dementia patients predicts low-grade hypercoagulability in spousal caregivers

BACKGROUND

Low-grade hypercoagulability might be one pathway to explain how the chronic stress of dementia caregiving increases cardiovascular disease risk, but the specific aspects of caregiver stress that elicit hypercoagulability are elusive. We hypothesized that dementia patients' problem behaviors and negative reactions of caregivers to these behaviors would relate to hypercoagulability in caregivers.

METHODS

One hundred and eight participants (mean age 74 +/- 8 years, 70% women) providing in-home care for their spouse with Alzheimer's disease were examined. Caregivers were interviewed about the number of 24 predefined patient problem behaviors in the previous week (range 0-24) and how upset or bothered they felt in response to these behaviors (total score 0-96). Von Willebrand factor, plasminogen activator inhibitor-1, and D-dimer were determined in plasma and standardized z-scores of their concentrations summed into a procoagulant index.

RESULTS

Greater number of problem behaviors (Delta R(2) = 0.046, p = .014) and negative reactions of caregivers to these behaviors (Delta R(2) = 0.044, p = .017) were associated with greater procoagulant index after controlling for sociodemographic factors, major cardiovascular risk factors, health habits, and health problems. However, the number of and reaction to problem behaviors did not significantly predict procoagulant activity independent from each other. Post hoc analysis revealed a positive association between the number of problem behaviors and D-dimer (p = .010, Delta R(2) = 0.053), even when controlling for negative reactions (p = .033, Delta R(2) = 0.036). Caregiver reaction to problem behaviors was not significantly associated with any procoagulant factor individually.

CONCLUSION

Alzheimer patients' problem behavior and their negative appraisal by the caregiver may contribute to the chronic low-grade hypercoagulable state in dementia caregivers.

Longitudinal platelet reactivity to acute psychological stress among older men and women

Platelet reactivity to acute stress is associated with increased cardiovascular disease risk; however, little research exists to provide systematic methodological foundations needed to generate strong longitudinal research designs. Study objectives were: 1) to evaluate whether markers of platelet function increase in response to an acute psychological stress test among older adults, 2) to establish whether reactivity remains robust upon repeated administration (i.e. three occasions approximately 1 year apart), and 3) to evaluate whether two different acute speech stress tasks elicit similar platelet responses. The 149 subjects (mean age 71 years) gave a brief impromptu speech on one of two randomly assigned topics involving interpersonal conflict. Blood samples drawn at baseline and post-speech were assayed using flow cytometry for platelet responses on three outcomes (% aggregates, % P-selectin expression, and % fibrinogen receptor expression). Three-level hierarchical linear modeling analyses revealed significant stress-induced increases in platelet activation on all outcomes (p < 0.001). No significant habituation on any measure was found. Additional reactivity differences were associated with male gender, history of myocardial infarction, and use of aspirin, statins, and antidepressants. The results demonstrate that laboratory acute stress tests continued to produce robust platelet reactivity on three activation markers among older adults over 3 years.

Persistent versus transient depressive symptoms in relation to platelet hyperactivation: a longitudinal analysis of dementia caregivers

BACKGROUND

Depressive symptoms and caregiving stress may contribute to cardiovascular disease (CVD) via chronic platelet activation; however, it remains unclear whether this elevated activation constitutes a trait or state marker. The primary objective was to investigate whether persistent depressive symptoms would relate to elevated platelet activation in response to acute psychological stress over a three-year period.

METHODS

Depressive symptoms (Brief Symptom Inventory) were assessed among 99 spousal dementia caregivers (52-88 years). Platelet P-selectin expression was assessed in vivo using flow cytometry at three time-points over the course of an acute stress test: baseline, post-stress, and after 14 min of recovery. Two competing structural analytic models of depressive symptoms and platelet hyperactivity with three yearly assessments were compared.

RESULTS

Although depressive symptoms were generally in the subclinical range, their persistent elevation was associated with heightened platelet reactivity and recovery at all three-years while the change in depressive symptoms from the previous year did not predict platelet activity.

LIMITATIONS

These results focus on caregivers providing consistent home care, while future studies may extend these results by modeling major caregiving stressors.

CONCLUSIONS

Enduring aspects of negative affect, even among those not suffering from clinical depression are related to hemostatic changes, in this case platelet reactivity, which might be one mechanism for previously reported increase in CVD risk among elderly Alzheimer caregivers.

The hidden patient: addressing the caregiver

Premium caregiving is pivotal to achieve quality care for persons with chronic or disabling conditions. Unpaid informal caregivers currently provide for a substantial proportion of care recipient needs including 80% of long-term care needs in the United States. Within the next 2 decades, 78 million baby boomers will reach 65 years of age and older, creating unique and extensive challenges to an already flawed health care system; this older cohort will at minimum increase utilization of health care resources. On an individual level, care providers need to support and educate caregivers and make caregivers partners in the delivery of excellent care. To achieve this, health care professionals need to educate themselves regarding the caregivers' demographics, ethnicity, characteristics, effective interventions, and outcomes. From a health policy perspective, public, private, and community funding needs to be allocated to advocate for, encourage, and train these caregivers.

A 5-year longitudinal study of the relationships between stress, coping, and immune cell beta(2)-adrenergic receptor sensitivity

Caring for a spouse with Alzheimer's disease (AD) is associated with overall health decline and impaired cardiovascular functioning. This morbidity may be related to the effects of caregiving stress and impaired coping on beta(2)-adrenergic receptors, which mediate hemodynamic and vascular responses and are important for peripheral blood mononuclear cell (PBMC) trafficking and cytokine production. This study investigated the longitudinal relationship between stress, personal mastery, and beta(2)-adrenergic receptor sensitivity assessed in vitro on PBMC. Over a 5-year study, 115 spousal AD caregivers completed annual assessments of caregiving stress, mastery, and PBMC beta(2)-adrenergic receptor sensitivity, as assessed by in vitro isoproterenol stimulation. Heightened caregiving stress was associated with significantly decreased receptor sensitivity, whereas greater sense of personal mastery was associated with significantly increased receptor sensitivity. These results suggest that increased stress may be associated with a desensitization of beta(2)-receptors, which may contribute to the development of illness among caregivers. However, increased mastery is associated with increased receptor sensitivity, and may therefore serve as a resource factor for improved health in this population.

Effects of depressive and anxious symptoms on norepinephrine and platelet P-selectin responses to acute psychological stress among elderly caregivers

BACKGROUND

Caring for a spouse with Alzheimer's disease is associated with increased psychological distress, impaired immunity, and heightened cardiovascular risk. Hyperreactivity of sympathetic and platelet activation responses to acute psychological stress, or the failure to recover quickly from stressful events, may constitute an important pathway linking stress and negative affect with cardiovascular disease (CVD).

OBJECTIVES

(1) To evaluate associations between negative affect (i.e., depressive and anxious symptoms) with increased norepinephrine and P-selectin responses to an acute psychological stress task. (2) To establish whether these associations are augmented among elderly spousal caregivers (CG) compared to non-caregivers (NC).

METHODS

Depressive (DEP) and anxious (ANX) symptoms from the Brief Symptom Inventory were assessed among 39 CG and 31 NC. Plasma norepinephrine levels (NE) and percent platelet P-selectin (PSEL) expression were assayed at three time-points: rest, immediately following a laboratory speech test (reactivity), and after 14 min of recovery.

RESULTS

Among CG, but not NC, increased symptoms of depression and anxiety were associated with delayed NE recovery (DEP: beta=.460, p=.008; ANX: beta=.361, p=.034), increased PSEL reactivity (DEP: beta=.703, p<.001; ANX: beta=.526, p=.002), and delayed PSEL recovery (DEP: beta=.372, p=.039; ANX: beta=.295, p=.092), while controlling for age, gender, aspirin use, antidepressant use, and preexisting CVD. Bivariate correlations showed delayed NE recovery was also associated with increased PSEL reactivity (r=.416) and delayed PSEL recovery (r=.372; all ps<.05) among CG but not NC.

DISCUSSION

Among chronically stressed caregivers, increased levels of depressive and anxious symptoms are associated with prolonged sympathetic activation and pronounced platelet activation. These changes may represent one pathway linking caregiving stress to cardiovascular risk.

Combination of caregiving stress and hormone replacement therapy is associated with prolonged platelet activation to acute stress among postmenopausal women

OBJECTIVE

To investigate the combined effects of caregiving and hormone replacement therapy (HRT) on platelet hyperactivity to acute psychological stress. Both HRT and the chronic stress of caregiving have been associated with increased cardiovascular risk, potentially through a mechanism of platelet hyperactivity.

METHODS

A total of 78 elderly postmenopausal women (51 caregivers (CG) and 27 noncaregivers (NC)) were assessed for platelet activation in response to a laboratory speech test. Half the sample was taking HRT. Blood was sampled at baseline, post speech, and after 14 minutes of recovery. Platelet activation was assessed through whole blood flow cytometry assays of % aggregates (Agg), and expression of % fibrinogen receptors (FbR) and % P-selectin (P-sel) on platelet surface.

RESULTS

Multivariate repeated-measures analysis of variance revealed that CG taking HRT exhibited significantly prolonged platelet activation in response to acute stress. There was an interaction between HRT and CG on recovery from stress for Agg (F (1,71) = 5.260, p = .025), P-Sel (F(1,71 = 6.426, p = .013), and FbR (F(1,71 = 6.653, p = .012), controlling for age, cardiovascular disease, and aspirin. Among HRT users, regression analysis revealed that CG had delayed recovery of Agg (beta = 0.354, t(34) = 2.154, p = .038) and P-sel (beta = 0.498, t(34)=3.126, p = .004) from stress relative to NC. No caregiving effects on recovery were present among non-HRT users. In addition, these effects were maintained after controlling for health behaviors, medications, and medical conditions.

CONCLUSION

Chronic dementia caregiving stress in combination with HRT may impair recovery of platelet activation after acute mental stress (i.e., activation levels do not quickly return to resting levels), thereby potentially increasing cardiovascular risk among CG who take HRT.

Effects of placement and bereavement on psychological well-being and cardiovascular risk in Alzheimer's caregivers: a longitudinal analysis

OBJECTIVE

We examined the impact of Alzheimer caregiver transitions (i.e., placement and bereavement) on psychological outcomes and on plasma D-dimer levels, an end product of the coagulation cascade associated with increased cardiovascular risk.

METHODS

This was a prospective study in which 126 spousal caregivers of Alzheimer's patients were assessed each year for 5 years. We used random regression models to evaluate discontinuous change in our outcomes over time, with emphasis on the impact of caregiver transitions on psychological and physical well-being.

RESULTS

Caregivers experienced immediate improvement in overload and mastery following transitions, and these improvements were maintained over time. There was also a significant drop in depressive symptoms immediately following placement of spouses. D-dimer rose significantly over time but began to significantly decline at 6-months posttransitions.

CONCLUSIONS

Caregiver transitions appear to produce immediate and long-term "normalization" of psychological health in caregivers. This normalization also appears related to "downstream" reductions in D-dimer.