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

Fear of cancer recurrence and change in hair cortisol concentrations in partners of breast cancer survivors

PURPOSE

Partners of breast cancer (BC) survivors report high rates of psychological distress including fear of cancer recurrence (FCR). Research suggests that partners may have poorer physical health outcomes than the general population, but little research has examined the physiological biomarkers by which distress may impact partner health outcomes. The current study examined the associations between FCR and changes in hair cortisol among BC partners.

METHODS

Male partners (N = 73) of early-stage BC survivors provided hair samples during two visits, one after completion of survivors' adjuvant treatment (T1) and again 6 months later (T2). Two subscales from the Fear of Cancer Recurrence Inventory and one subscale from the Concerns about Recurrence Scale comprised a latent FCR factor at T1. A latent change score model was used to examine change in cortisol as a function of FCR.

RESULTS

Partners were on average 59.65 years of age (SD = 10.53) and non-Hispanic White (83%). Latent FCR at T1 was positively associated (b = 0.08, SE = 0.03, p = .004, standardized β = .45) with change in latent hair cortisol from T1 to T2.

CONCLUSIONS

Results indicated that greater FCR was associated with increases in hair cortisol in the months following adjuvant treatment. This is one of the first studies to examine the physiological correlates of FCR that may impact health outcomes in BC partners.

IMPLICATIONS FOR CANCER SURVIVORS

Findings highlight the need for further research into the relationship between FCR and its physiological consequences. Interventions to address partner FCR are needed and may aid in improving downstream physical health outcomes.

Nature-based virtual reality intervention to manage stress in family caregivers of allogeneic hematopoietic stem cell transplant recipients: a two-phase pilot study protocol

Millions of family members and/or friends in the U.S. serve as unpaid caregivers for individuals with chronic conditions, such as cancer. Caregiving for someone undergoing an intense allogeneic hematopoietic stem cell transplant (HSCT) is particularly demanding, with accompanying physical and psychological stress. Increased stress and stress-related symptoms could make it difficult for caregivers to fulfill their roles and could negatively impact the health status and quality of life of themselves and the recipients. Virtual reality (VR) is a promising technology increasingly used for treatment and wellness in various medical settings. There is growing evidence that studies have reported the positive effects of the VR intervention in managing and reducing stress among diverse populations in various clinical scenarios; however, no published studies have focused on family caregivers of patients with cancer. The study aims to assess the feasibility and acceptability of a four-week nature-based VR intervention and to examine the effectiveness of the VR intervention on stress in HSCT caregivers. This study comprises two phases. Phase I of the study will be a single-arm pre-post design focused on assessing the feasibility and acceptability of the VR intervention. Phase II of the study will be a prospective randomized controlled group design to examine the effectiveness of the VR intervention on perceived stress. Adults (≥ 18 years) who serve as primary caregivers for a person who will undergo an allogeneic HSCT will be recruited. Fifteen participants will be enrolled for Phase I and 94 participants for Phase II (Active VR arm N=47; Sham VR arm N=47). The nature-based immersive VR program contains 360° high-definition videos of nature scenes along with nature sounds through a head-mounted display (HMD) for 20 minutes every day for four weeks. Primary outcome is perceived stress measured by the Perceived Stress Scale. Secondary/exploratory outcomes are stress-related symptoms (e.g., fatigue, sleep disturbance) and physiological biomarkers (e.g., cortisol, alpha-amylase). The importance and innovativeness of this study consist of using a first-of-its-kind, immersive VR technology to target stress and investigating the health outcomes assessed by validated objective biomarkers as well as self-report measures of the nature-based intervention in the caregiver population.

Clinical trial registration

ClinicalTrials.gov, identifier NCT05909202.

A Biomarker of Stress and Self-reported Caregiving Distress Predict Poor Quality of Life in Family Caregivers of Patients With Heart Failure

BACKGROUND

Family caregivers are at a high risk for low quality of life due to caregiving-related stress. Caregivers' stress is commonly assessed using self-reported measures, which reflect relatively subjective and long-term stress related to caregiving, but objective biological markers of stress are rarely used for caregivers. The purposes of this study were (1) to determine whether caregiver characteristics were associated with stress assessed using a stress biomarker (serum cortisol) and a self-reported caregiving distress measure (Caregiver Burden Inventory) and (2) to determine the predictability of both stress measures for quality of life in caregivers of patients with heart failure.

METHODS

Taiwanese family caregivers (N = 113; mean age, 54.5 years; 70.8% female) of patients with heart failure completed surveys including caregiving distress and quality of life measured by the Caregiver Burden Inventory and the Short Form-36 (physical and psychological well-being subscales), respectively, and provided blood samples for serum cortisol. Independent t tests, correlation, and hierarchical regression were conducted.

RESULTS

Single caregivers had higher serum cortisol levels than married caregivers (P = .002). Men had significantly higher serum cortisol levels than women (P = .010), but men reported lower caregiving distress than women (P = .049). Both serum cortisol (β = -0.32, P = .012) and caregiving distress (β = -0.29, P = .018) were significant predictors of quality of life in the physical well-being scale while controlling for caregivers' characteristics and depressive symptoms. Serum cortisol (β = -0.28, P = .026) and caregiving distress (β = -0.25, P = .027) also predicted quality of life in the psychological well-being scale.

CONCLUSIONS

Serum cortisol and self-reported caregiving distress have similar predictability for quality of life in family caregivers of patients with heart failure. Reducing stress and caregiving distress is critical to improving quality of life in this population.

Effects of a yoga-based stress reduction intervention on stress, psychological outcomes and cardiometabolic biomarkers in cancer caregivers: A randomized controlled trial

Caregiving stress is a risk factor for cardiometabolic disease. Therefore, integrating cardiometabolic biomarkers into caregiving research provides a more comprehensive assessment of an individual’s health and response to an intervention. The objective of this study was to examine the effects of a yoga-based stress reduction intervention on stress, psychological outcomes, and cardiometabolic biomarkers in cancer caregivers. This prospective randomized controlled trial enrolled family caregivers of adult patients who underwent an allogeneic HSCT at the National Institutes of Health (NIH) Clinical Center. All subjects received usual care education. Participants in the intervention group received an Iyengar yoga intervention self-administered over six weeks using an audio recording file. The primary outcome was perceived stress (measured using the NIH toolbox Perceived Stress). The secondary outcomes were psychological factors (depression and anxiety measured using PROMIS® Depression and Anxiety), and cardiometabolic biomarkers measured by nuclear magnetic resonance spectroscopy. A total of 50 family caregivers (mean [SD] age, 44.9 [15.2] years; 42 [84.0%] women) were randomized, 25 to the intervention group and 25 to the control group. No group differences were noted in stress, depression, and anxiety. Significant interaction effects between group and time were found in large TRL-P (F(1,43) = 10.16, p = 0.003) and LP-IR (F(1,42) = 4.28, p = 0.045). Post-hoc analyses revealed that the levels of large TRL-P (mean difference = 1.68, CI = [0.86, 2.51], p< .001) and LP-IR (mean difference = 5.67, CI = [1.15, 10.18], p = 0.015) significantly increased over time in the control group but while remained stable in the intervention group (mean difference = -0.15, CI = [-0.96, 0.66], p = 0.718; mean difference = -0.81, CI = [-5.22, 3.61], p = 0.714, respectively). Even when perceptions of psychological distress remain unchanged, incorporating gentle yoga poses and breathing exercises may reduce the risk of cardiometabolic disease in caregivers by inhibiting the development of insulin resistance. Standard lipids of cardiometabolic risk do not appear to be robust enough to detect short-term early changes of cardiometabolic risk in caregivers.

Trial registration: ClinicalTrials.gov Identifier: NCT02257853.

Cognitive behavioral therapy versus general health education for family caregivers of individuals with heart failure: a pilot randomized controlled trial

Background

While support from family caregivers is essential in the care of patients with heart failure (HF), caregiving places a considerable burden on family caregivers. We examined the preliminary effects of cognitive behavioral therapy (CBT) for caregivers of individuals with HF.

Methods

In this pilot randomized controlled trial, patients with HF and their primary family caregivers (30 dyads) were randomized into CBT (n = 15) or general health education (GHE, n = 15) groups. Caregivers received 8 weekly individual sessions of either CBT (intervention) or GHE (attention control condition). Caregivers completed questionnaires at baseline, post-intervention, and 6 months. Saliva samples collected from caregivers at baseline and post-intervention were analyzed for salivary cortisol. The cortisol awakening response (CAR) and area under the curve (AUC) were calculated using log-transformed cortisol values. We analyzed data from 26 (14 receiving CBT and 12 receiving GHE) caregivers who received at least one session of CBT or GHE (modified intention-to treat) using linear mixed models. Each model included time, study group, and time-by-study group interaction as fixed effects.

Results

Patients were older (66.94 ± 14.01 years) than caregivers (55.09 ± 15.24 years), and 54% of patients and 54% of caregivers were female. Most caregivers (58%) were spouses. A total of 14 (93%) CBT and 12 (80%) GHE participants received at least 1 session (p = .60), and 11 (73%) CBT and 11 (73%) GHE participants completed all 8 sessions (p = 1.00). There were no significant between-group differences in change for salivary cortisol or psychological outcomes. However, the CBT group had significant within-group improvements in perceived stress (p = .011), stress symptoms (p = .017), depression (p = .002), and anxiety (p = .006) from baseline to post-intervention, while the control group had no significant within-group change in the outcomes except for anxiety (p = .03). The significant improvements observed in the CBT group lasted for 6 months. No adverse effects were observed.

Conclusions

In this pilot trial, although between-group differences in change were not significant, CBT resulted in significant improvements in some psychological outcomes with no improvement in the control group. Our findings suggest the potential of the intervention to alleviate psychological distress in HF caregivers. Further examination in larger randomized trials is warranted.

Trial registration

ClinicalTrials.gov Identifier: NCT01937936 (Registered on 10/09/2013).

Caregivers of patients with cancer: perceived stress, quality of life and immune function

OBJECTIVES

To examine the mediating effect of quality of life (QoL) on the relationship between perceived stress and immune function in Korean family caregivers of patients with cancer.

METHODS

In this cross-sectional study, 89 family caregivers of patients with cancer completed perceived stress and QoL questionnaires. Immune function was assessed using two proinflammatory biomarkers, IL-6 and tumour necrosis factor-alpha (TNF-α). Multiple parallel mediator regression was conducted using four mediators (burden, lifestyle disruption, positive adaptation and financial concern) representing the subscales of QoL related to caregiving.

RESULTS

Psychological (indirect effect (ab)=-0.52, 95% CI -1.25 to -0.01) and physical (ab=-0.44, 95% CI -1.07 to -0.05) stress had a significant indirect effect on IL-6 levels attributed to lifestyle disruption associated with caregiving. Psychological (ab=-0.97, 95% CI -2.37 to -0.11) and physical (ab=-1.10, 95% CI -2.87 to -0.08) stress also had a significant indirect effect on TNF-α as a result of financial concerns owing to caregiving. Other indirect effects of psychological/physical stress on inflammation were not significant.

CONCLUSION

This study demonstrated that the effects of perceived psychological and physical stress on IL-6 and TNF-α levels were mediated by the caregiver's QoL, especially lifestyle disruption and financial concerns. Stress management and improvement of caregivers' QoL related to lifestyle disruption and financial issues should be considered to reduce the negative effects of caregiving on immune function.

Caregiving stress and burden associated with cardiometabolic risk in family caregivers of individuals with cancer

Chronic stress is a well-established risk factor for cardiometabolic disease. Caregiving for individuals with cancer is perceived as a chronic stressor yet research on the risk for cardiometabolic disease in this population, opposed to the elderly and those with Alzheimer's disease, is limited. Additionally, few studies have explored the early physiological changes that occur in family caregivers suggesting an elevated risk for illness. This cross-sectional study was designed to examine levels of cardiometabolic risk biomarkers and their correlates in caregivers of patients with colorectal cancer. Caregivers completed questionnaires that measure exposures to stress and vulnerability factors, psychological distress, and health habits as potential correlates. Traditional lipid and nontraditional lipoprotein particle biomarkers (e.g. concentration and size for all lipoprotein classes) were assayed from blood serum. Caregivers (N = 83, mean age = 49.8, 73% female) displayed levels of cardiometabolic biomarkers that suggest an elevated risk for cardiometabolic disease. Caregivers who were Hispanic, married, highly educated, employed, reported more hours spent caregiving daily, experienced higher caregiver burden associated with the lack of family support and impact on schedule, and psychological distress, demonstrated an elevated risk for cardiometabolic disease; primarily determined by nontraditional lipid biomarkers - large TRL-P, LDL-P, small HDL-P, large HDL-P, TRL-Z, LDL-Z and HDL-Z. These findings suggest that traditional lipid biomarkers may not be robust enough to detect early physiological changes associated with cardiometabolic disease risk in family caregivers. Moreover, findings reiterate the importance of assessing caregiver burden and providing evidence-based interventions to manage caregiving stress with the potential to improve caregivers' cardiometabolic health.

Association of cancer caregiver stress and negative attribution style with depressive symptoms and cortisol: a cross-sectional study

PURPOSE

We examined the effect of informal cancer caregiver stress and negative attribution style (NAS) on depressive symptoms and salivary cortisol.

METHOD

The sample came from a hospital bone marrow unit and caregiver support organizations and included 60 informal cancer caregivers (51.7% partners) of individuals with cancer (provided care for a median of 27.5 h per week for 12 months) and 46 non-caregiver participants. In this cross-sectional study, participants completed questionnaires assessing NAS and depressive symptoms and provided saliva samples to measure cortisol.

RESULTS

Linear regressions demonstrated that cancer caregiver stress (p = 0.001) and the cancer caregiver stress by NAS interaction (p = 0.017), but not NAS alone (p = 0.152), predicted depressive symptoms. Caregivers independent of their NAS and non-caregivers high in NAS reported high depression while non-caregivers low in NAS reported low depression. Neither cancer caregiver stress (p = 0.920) nor NAS alone (p = 0.114), but their interaction, predicted cortisol (p = 0.036). Higher NAS was associated with a higher cortisol in both groups while non-caregivers had higher cortisol than caregivers.

CONCLUSIONS

If the findings can be replicated, consideration of NAS in existing interventions to support informal cancer caregivers in managing chronic stress appears warranted.

Caregiver subjective and physiological markers of stress and patient heart failure severity in family care dyads

Greater family caregiver exposure to uncontrolled patient symptoms is predictive of greater caregiver psychological and physiological stress in dementia and other chronic illnesses, but these phenomena have not been well-studied in heart failure (HF) - a disease with high symptom burden. The purpose of this study was to test the hypothesis that worse patient functional status (as reflected by increasing HF symptoms) would be associated with elevated psychological and physiological stress for the caregiver. This was a secondary analysis of data from 125 HF caregivers in the Caregiver Opportunities for Optimizing Lifestyle (COOL) study. Psychological stress was measured on four dimensions: care-related strain/burden (Oberst Caregiving Burden Scale), depression (Center for Epidemiological Studies Depression Scale), anxiety (State-Trait Anxiety Index), and general stress (Perceived Stress Scale). Physiological stress was measured by markers of HPA axis function (elevated cortisol awakening response [CAR]), endothelial dysfunction (increased PAI-1), and inflammation (increased IL-6, hsCRP). HF patient functional status was quantified by caregiver assessment of New York Heart Association (NYHA) Class. Generalized linear models were used to test associations between patient NYHA Class and stress (one model per indicator). NYHA Class (ordinal) was backwards difference coded in each model to examine caregiver stress in relation to increasing levels of HF severity. Caregivers were mostly female and in their mid-fifties, with a slight majority of the sample being African American and the patient's spouse. Overall, patient functional status was associated with greater caregiver psychological and physiological stress. In terms of psychological stress, higher NYHA Class was significantly associated with greater caregiver anxiety and general stress, but not with caregiver burden or depression. In terms of physiological stress, higher NYHA Class was associated with elevated markers in all models (elevated CAR and higher IL-6, hsCRP, and PAI-1). Across models, most associations between NYHA Class and stress were present at relatively early stages of functional limitation (i.e. Class II), while others emerged when functional limitations became more severe. To inform timing and mechanisms for much-needed caregiver interventions, research is needed to determine which aspects of HF symptomatology are most stressful for caregivers across the HF trajectory.

Glucocorticoid resistance and β2-adrenergic receptor signaling pathways promote peripheral pro-inflammatory conditions associated with chronic psychological stress: A systematic review across species

Activation of the HPA-axis and SNS are widely accepted to link chronic stress with elevated levels of peripheral pro-inflammatory markers in blood. Yet, empirical evidence showing that peripheral levels of glucocorticoids and/or catecholamines mediate this effect is equivocal. Recent attention has turned to the possibility that cellular sensitivity to these ligands may contribute to inflammatory mediators that accompany chronic stress. We review current evidence for the association of chronic stress with glucocorticoid receptor (GR) and β-adrenergic receptor (β-AR) signaling sensitivity. Across 15 mouse, 7 primate, and 19 human studies, we found that chronic stress reliably associates with downregulation in cellular GR sensitivity, alterations in intracellular β-AR signaling, and upregulation in pro-inflammatory biomarkers in peripheral blood. We also present evidence that alterations in GR and β-AR signaling may be specific to myeloid progenitor cells such that stress-related signaling promotes release of cells that are inherently less sensitive to glucocorticoids and differentially sensitive to catecholamines. Our findings have broad implications for understanding mechanisms by which chronic stress may contribute to pro-inflammatory phenotypes.

Design and validation of an electrophysiological based tool to assess chronic stress. Case study: burnout syndrome in caregivers

Caregiver burnout syndrome is an increasingly seen condition, although the subjective nature of self-administered psychometric tests and the lack of a consensual diagnostic tool might hinder a proper diagnosis. The availability of objective psychosomatic measures of stress might facilitate the early diagnosis and clinical management of these patients. For this reason, the aim of this work was to develop a quantitative tool to evaluate the stress level of caregivers in a noninvasive and repeatable manner. An observational, controlled, matched study was designed including a group of 38 principal caregivers of chronic patients and a control group of 38 non-caregivers. Psychometric, biochemical, and electrophysiological data were analyzed along with sociodemographic data. A quantitative chronic stress reference scale (CSRs) was constructed based on the weighted contribution of several psychometric and biochemical variables and afterwards, a predictive psychosomatic model (ESBSm) correlated with CSRs was elaborated from extracted variables of several electrophysiological signals monitored for 10 min. The resulting CSR scale shows a high power to discriminate caregivers from the control group while the ESBSm shows a 79% correlation with the CSR scale validated through a 5-fold process. Therefore, the results demonstrate that the ESBS model is an objective and validated tool to diagnose the degree of stress linked to burnout in caregivers of chronic patients from a 10-min session of noninvasive monitoring with a reliability equivalent to the questionnaires currently used to quantify stress in caregivers.

Repetitive Negative Thinking, Depressive Symptoms, and Cortisol in Cancer Caregivers and Noncaregivers

OBJECTIVES

To examine the effect of informal cancer caregiving and repetitive negative thinking (RNT) on depressive symptoms and salivary cortisol levels.

SAMPLE & SETTING

The sample was recruited from a hospital bone marrow unit and caregiver support organizations. It included 60 informal cancer caregivers (52% partners) of individuals with cancer who provided care for a median of 27.5 hours per week for 12 months, and 46 noncaregiver participants.

METHODS & VARIABLES

In this cross-sectional study, participants completed questionnaires assessing RNT and depressive symptoms and provided saliva samples to measure cortisol levels.

RESULTS

Cancer caregiving and RNT, but not the interaction, were associated with more depressive symptoms. RNT, but not cancer caregiving, was associated with salivary cortisol. A disordinal interaction effect suggests that cancer caregiving was associated with lower cortisol levels, and RNT in noncaregivers was associated with higher cortisol levels.

IMPLICATIONS FOR NURSING

Given that RNT is related to depressive symptoms and cortisol, connecting cancer caregivers who experience RNT to resources and the development and evaluation of brief nurse-led interventions to reduce RNT in informal cancer caregivers seems warranted.

Family Caregiving for Cancer Patients: the State of the Literature and a Direction for Research to Link the Informal and Formal Care Systems to Improve Quality and Outcomes

OBJECTIVES

Based on recent shifts in reimbursement for cancer treatment from fee-for-service to bundled and value-based payment, this concluding article summarizes data from these papers and the large body of literature on caregiving to suggest how caregiving research might be redirected to link the formal with the informal systems to achieve higher-quality and lower-cost care. Caregiver dyads, the tasks of care, and strategies for training are presented.

DATA SOURCES

Articles in this issue of Seminars in Oncology Nursing, the larger body of caregiving literature, and the Oncology Care Model driving bundled payments and value-based care.

CONCLUSION

Research on informal caregiving for cancer patients should begin to reframe the rich body of evidence available toward a focus on caregivers reactions to the tasks of care, the training necessary for caregivers to perform them, and how each contributes to quality care at lower costs and appropriate outcomes given patients' stage of disease and goals of treatment.

IMPLICATIONS FOR NURSING PRACTICE

Oncology systems must take a more active role in including patients and their families as partners to manage treatments and side effects to achieve the best possible patient outcomes. They must be able to evaluate the patient and the caregiver to determine what tasks they will be able to perform, and then make sure they have the training and resources to carry out those tasks. Training could be done by social media and through communication using patient portals that could be expanded through the electronic medical records to include caregiver portals, enabling caregiver questions and reports of patients' conditions.