Assessing sleep architecture in dementia caregivers at home using an ambulatory polysomnographic system

Irregular sleep-wake rhythm disorder: From the pathophysiologic perspective to the treatment

Irregular sleep-wake rhythm disorder (ISWRD) is an intrinsic circadian rhythm disorder caused by loss of the brain's circadian regulation, through changes of the input and/or output to the suprachiasmatic nucleus (SCN), or of the SCN itself. Although there are limited prevalence data for this rare disease, ISWRD is associated with neurodegenerative disorders, including the Alzheimer disease (AD) and the Parkinson disease (PD), which will become increasingly prevalent in an aging population. It additionally presents in childhood developmental disorders, psychiatric disorders, and traumatic brain injury (TBI). Patients present with unpredictable, short sleep periods over a 24-h period, with significant day-to-day and weekly variability. Symptoms manifest as insomnia and excessive daytime sleepiness. Sleep logs and actigraphy monitoring capture rest-activity patterns required for diagnosis. Treatment aims to enhance external circadian cues through timed light therapy, behavioral activity regimens, and melatonin, but efficacy remains quite limited. Pathophysiology of ISWRD in association with various diseases and their specific management are discussed. There is a need for further investigation of disease pathophysiology, development of widely applicable tools for diagnosis, and development of treatments.

Sleep quality differences among caregivers for persons living with and without dementia

OBJECTIVES

This study examined the relationship between caring for a person with/without dementia and caregiver sleep quality, and analyzed the extent to which perceived benefits of caregiving and assessments of caregiver-recipient relationship quality explain the relationship between care recipient dementia status and caregiver sleep quality.

METHOD

Data were analyzed from caregivers for persons with no or probable dementia who participated in the 2017 National Study of Caregiving (NSOC) and National Health and Aging Trends Study. Caregiver sleep quality was measured using NSOC time diary interview. Perceptions of caregiving and relationship quality were assessed using 4-item surveys. We used multivariable logistic regressions to examine the association between care recipient dementia status and caregiver sleep quality controlling for covariates.

RESULTS

The sample consisted of 1,374 caregivers (mean age = 62.3, SD = 14, 68.3% women, 69.4% non-Hispanic White). In multivariable models adjusting for caregiver and care recipient characteristics, being a caregiver for someone with dementia was associated with 23% lower odds of reporting "excellent/very good" sleep quality (OR: 0.77, 95%CI: 0.61-0.98, p = 0.032). Greater perception of caregiving benefits was associated with 8% greater odds of "excellent/very good" sleep quality (AOR: 1.08, 95%CI: 1.02-1.15, p = 0.013), but did not explain the relationship between dementia and caregiver sleep quality. Positive ratings of relationship quality explained the relationship between care recipient dementia status and caregiver sleep quality (AOR: 0.82, 95%CI: 0.65-1.05, p = 0.12).

CONCLUSION

Improving assessments of relationship quality and amplifying perceptions of caregiving benefits may reduce disparities in sleep quality between caregivers of persons living with or without dementia.

Correlates of Sleep Disturbance Experienced by Informal Caregivers of Persons Living with Dementia: A Systematic Review

OBJECTIVES

This study aims to comprehensively review and update the literature concerning the correlates of sleep disturbance among caregivers of persons living with Alzheimer's disease and related dementias to identify gaps in the literature and antecedent targets for interventions.

METHODS

We searched PubMed, CINAHL, PsycINFO, and Embase using terms related to "sleep," "caregiver," and "dementia."

RESULTS

Thirty-six articles were included in this review. Based on the antecedents within the 3P model of insomnia, predisposing factors associated with caregiver sleep included caregiver demographics, and physiological factors like genotype and biomarkers. Precipitating factors related to caregiver sleep included caregiving status and responsibilities, and person living with dementia factors.

CONCLUSIONS

Sleep disturbance is a significant issue for caregivers of persons living with dementia. However, this review has identified multiple precipitating factors that are modifiable targets for interventions to improve or enhance caregiver sleep.

CLINICAL IMPLICATIONS

Numerous predisposing and precipitating factors contribute to caregivers of persons living with dementia being susceptible to sleep disturbance. Healthcare providers should ask patients about their caregiving status during annual visits. Healthcare providers should also evaluate caregivers' sleep patterns, and the predisposing and precipitating factors of sleep disturbance, with a focus on the modifiable factors, to enable timely intervention.

The Effect of Tele-Savvy on Sleep Quality and Insomnia in Caregivers of Persons Living with Dementia

Introduction

Sleep disturbance is prevalent in caregivers of persons living with dementia (PLwD). Tele-Savvy, a 7-week virtual psychoeducational intervention, enhances caregivers' competence and self-care, and reduces depression. While not explicitly designed to do so, Tele-Savvy can potentially improve caregivers' disturbed sleep. The present study aimed to examine the longitudinal effects of Tele-Savvy on caregivers' sleep quality and insomnia.

Methods

This was a secondary data analysis of a 3-arm randomized control trial [Tele-Savvy (active treatment), Healthy Living (attention control), and usual care (waitlist control)]. Multilevel mixed modeling with intent-to-treat principles tested for group, time, and group-by-time effects. Effect sizes were estimated for all changes from baseline to the initial 6-month post-intervention point. Following completion of the 6-month post-randomization delay, we examined combined outcomes for Tele-Savvy.

Results

Participants (n=137; mean age 64.7 years) were predominantly female (68.6%) and White (68.6%). We found no initial group-by-time effects for the Pittsburgh Sleep Quality Index (PSQI) and the Insomnia Severity Index (ISI). For the combined Tele-Savvy group, there was a statistically significant improvement in ISI scores across time (p=0.050). The combined Tele-Savvy effect size for PSQI was d=0.126 and ISI was d=0.310.

Discussion

Tele-Savvy resulted in a significant long-term reduction in insomnia symptoms in this sample of caregivers of PLwD and demonstrated a positive trend for improvement in their sleep quality. Since sleep disturbance is so prevalent among caregivers of PLwD, the inclusion of sleep health education into psychoeducation caregiver interventions may yield even better outcomes for caregivers.

Development and Initial Evaluation of Web-Based Cognitive Behavioral Therapy for Insomnia in Rural Family Caregivers of People With Dementia (NiteCAPP): Mixed Methods Study

BACKGROUND

Informal caregivers of people with dementia frequently experience chronic insomnia, contributing to stress and poor health outcomes. Rural caregivers are particularly vulnerable but have limited access to cognitive behavioral therapy for insomnia (CBT-I), a recommended frontline treatment for chronic insomnia. Web-based delivery promises to improve insomnia, particularly for rural caregivers who have limited access to traditional in-person treatments. Our team translated an efficacious 4-session standard CBT-I content protocol into digital format to create NiteCAPP.

OBJECTIVE

This study aimed to (1) adapt NiteCAPP for dementia caregivers to create NiteCAPP CARES, a tailored digital format with standard CBT-I content plus caregiver-focused modifications; (2) conduct usability testing and evaluate acceptability of NiteCAPP CARES' content and features; and (3) pilot-test the adapted intervention to evaluate feasibility and preliminary effects on sleep and related health outcomes.

METHODS

We followed Medical Research Council recommendations for evaluating complex medical interventions to explore user needs and adapt and validate content using a stepwise approach: (1) a rural dementia caregiver (n=5) and primary care provider (n=5) advisory panel gave feedback that was used to adapt NiteCAPP; (2) caregiver (n=5) and primary care provider (n=7) focus groups reviewed the newly adapted NiteCAPP CARES and provided feedback that guided further adaptations; and (3) NiteCAPP CARES was pilot-tested in caregivers (n=5) for feasibility and to establish preliminary effects. Self-report usability measures were collected following intervention. Before and after treatment, 14 daily electronic sleep diaries and questionnaires were collected to evaluate arousal, health, mood, burden, subjective cognition, and interpersonal processes.

RESULTS

The stepped approach provided user and expert feedback on satisfaction, usefulness, and content, resulting in a new digital CBT-I tailored for rural dementia caregivers: NiteCAPP CARES. The advisory panel recommended streamlining content, eliminating jargon, and including caregiver-focused content. Focus groups gave NiteCAPP CARES high usefulness ratings (mean score 4.4, SD 0.79, scored from 1=least to 5=most favorable; score range 4.2-4.8). Multiple features were evaluated positively, including the intervention's comprehensive and engaging information, caregiver focus, good layout, easy-to-access intervention material, and easy-to-understand sleep graphs. Suggestions for improvement included the provision of day and night viewing options, collapsible text, font size options, tabbed access to videos, and a glossary of terms. Pilot-test users rated usefulness (mean score 4.3, SD 0.83; range 4.1-4.5) and satisfaction (mean score 8.4, SD 1.41, scored from 1=least to 10=most satisfied; range 7.4-9.0) highly. Preliminary effects on caregiver sleep, arousal, health, mood, burden, cognition, and interpersonal processes (all P<.05) were promising.

CONCLUSIONS

Adaptations made to standard digital CBT-I created a feasible, tailored digital intervention for rural dementia caregivers. Important next steps include further examination of feasibility and efficacy in a randomized controlled trial with an active control condition, a multisite effectiveness trial, and eventual broad dissemination.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04632628; https://clinicaltrials.gov/ct2/show/NCT04632628.

Sleep disturbances in Lewy body dementia: A systematic review

BACKGROUND

Lewy body dementia (LBD) refers to both dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD). Sleep disturbances are common in LBD, and can include poor sleep quality, excessive daytime sleepiness (EDS), and rapid eye movement behaviour disorder (RBD). Despite the high clinical prevalence of sleep disturbances in LBD, they are under-studied relative to other dementias. The aim of the present systematic review was to examine the nature of sleep disturbances in LBD, summarise the effect of treatment studies upon sleep, and highlight specific and necessary directions for future research.

METHODS

Published studies in English were located by searching PubMED and PSYCArticles databases (until 10 June 2022). The search protocol was pre-registered in PROSPERO (CRD42021293490) and performed in accordance with PRISMA guidelines.

RESULTS

Following full-text review, a final total of 70 articles were included. These included 20 studies focussing on subjective sleep, 14 on RBD, 8 on EDS, 7 on objective sleep, and 1 on circadian rhythms. The majority of the 18 treatment studies used pharmacological interventions (n = 12), had an open-label design (n = 8), and were of low-to-moderate quality. Most studies (n = 55) included only patients with DLB. Due to the heterogeneity of the studies, we reported a narrative synthesis without meta-analysis.

CONCLUSIONS

At least one form of sleep disturbance may be present in as many as 90% of people with LBD. Subjectively poor sleep quality, excessive daytime sleepiness, and RBD are more common and severe in LBD relative to other dementias.

Discrepancy between self-reported and objective sleep duration among dementia caregivers and noncaregivers

STUDY OBJECTIVES

Poor sleep, including short sleep duration, is common among caregivers of persons with dementia. However, it is unclear whether poor sleep is consistent across both self-reported and objective measures of sleep in caregivers. This study aimed to test the role of caregiving status (caregivers vs noncaregivers) on the discrepancy between self-reported and objective sleep duration.

METHODS

This was a cross-sectional study. Study participants were community-dwelling caregivers of spouses with dementia (n = 122) and noncaregivers (n = 53). A sleep duration discrepancy index was created by subtracting objective sleep duration measured with 3 consecutive 24-hour periods of actigraphy from self-reported sleep duration measured with the Pittsburgh Sleep Quality Index. Covariates included participants' demographic characteristics, depressive symptoms, positive and negative affects, personal mastery, and caregiving-role overload.

RESULTS

Caregivers showed a greater discrepancy in sleep duration than did noncaregivers (-0.46 hour vs 0.22 hour, respectively; P = .003). In a regression model, however, caregiving status was no longer associated with this sleep duration discrepancy, when covariates were accounted for. Higher positive affect was significantly associated with less sleep duration discrepancy (R2 = 11.3%, P = .014). The Sobel test of mediation showed that 26% of the effect of caregiving on this sleep discrepancy was attributable to caregivers with low positive affect.

CONCLUSIONS

The findings suggest a potential mediating role of positive affect on the relationship between caregiving status and sleep duration discrepancy. As an aid for understanding the role of lower positive affect, use of actigraphy may help address sleep discrepancy in caregivers.

CITATION

Song Y, Moore RC, Jeste DV, et al. Discrepancy between self-reported and objective sleep duration among dementia caregivers and noncaregivers. J Clin Sleep Med. 2022;18(8):1945-1952.

Sleep Quality Reports From Family Caregivers and Matched Non-caregiving Controls in a Population-Based Study

The stress of family caregiving may affect many health-related variables, including sleep. We evaluated differences in self-reported sleep quality between incident caregivers and matched non-caregiving controls from a national population-based study. Caregivers and controls were identified in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study and matched on seven different demographic and health history factors. Caregivers reported significantly longer sleep onset latency than controls, before and after adjusting for covariates (ps < .05). No differences were found on measures of total sleep time or sleep efficiency. Among caregivers only, employed persons reported less total sleep time and number of care hours was a significant predictor of total sleep time. Dementia caregivers did not differ from other caregivers. This is one of the few population-based studies of sleep quality in family caregivers. Additional research is needed to examine whether sleep disturbance contributes to greater health problems among caregivers.

Cognitive Function and Sleep in Caregivers of Persons Living with Dementia

Poor sleep is prevalent among caregivers of persons living with dementia and increases their risk for cognitive impairment and decline. In this cross-sectional, correlational study, we compared the cognitive function scores of caregivers with poor sleep with the demographically adjusted normed scores of the National Institutes of Health Toolbox Cognition Battery. Caregivers completed a 14-day sleep diary. On average, caregivers (n = 28) were 65.14 (±10.08) years, female, and White. Their average crystallized cognitive function composite score was significantly higher and their average fluid cognitive function composite score was significantly lower than the normative scores. Caregivers performed significantly worse on the processing speed domain measure. Poor sleep may affect how caregivers, including highly educated caregivers, process and respond to information, thus can influence how they safely perform complex caregiving tasks. Health care providers should consistently assess caregivers' sleep and cognitive abilities to promptly identify changes and provide timely interventions.

Using Telehealth to Deliver Cognitive Behavioral Treatment of Insomnia to a Caregiver of a Person With Alzheimer's Disease

Cognitive behavioral therapy for Insomnia (CBT-I) is the gold standard treatment for insomnia. There is limited access to qualified providers to deliver CBT-I; moreover, there are patient populations who struggle with access to insomnia care due to limited time and resources. This includes caregivers for persons with Alzheimer's disease, for whom sleep disturbance is a common concern. Utilizing telehealth to deliver CBT-I may be particularly important for vulnerable populations such as caregivers of persons with dementia, as it can offer an accessible, safe, and cost-effective treatment option that can be tailored to meet the needs of a specific population. This case study illustrates the successful implementation of a four-session CBT-I protocol through telehealth with a caregiver of a person with Alzheimer's disease. Given the success of this case and the conditions for psychological care the recent pandemic has created, continued research into the efficacy of sleep-related interventions through telehealth is warranted.

Family Caregivers of People with Dementia Have Poor Sleep Quality: A Nationwide Population-Based Study

Previous studies have documented cognitive impairments, psychological stress, and depressive symptoms in family caregivers of people with dementia (PWD), which could be attributed to their sleep disturbances. Notwithstanding the increasing recognition of poor sleep quality and sleep disturbances in family caregivers of PWD, their association has not been tested yet using population-representative samples. We conducted a retrospective, cross-sectional study using population-based data from the 2018 Korean Community Health Survey. Sociodemographic, mental health-related, and physical health-related variables as well as sleep quality evaluated by the Pittsburgh Sleep Quality Index (PSQI) were compared between 2537 cohabitating caregivers of PWD, 8864 noncohabitating caregivers of PWD, and 190,278 non-caregivers. Two sets of multivariable logistic regressions were conducted to examine the associations between dementia caregiving and poor sleep quality in cohabitating and noncohabitating caregivers versus noncaregivers. Both cohabitating and noncohabitating caregivers had higher global PSQI scores and higher prevalence of poor sleep quality (PSQI score > 5) than did noncaregivers. Multivariable logistic regressions adjusted for potential confounders revealed that cohabitating caregivers (odds ratio (OR) 1.26, 95% confidence interval (CI) 1.15-1.38) and noncohabitating caregivers (OR 1.15, CI 1.10-1.21) were significantly associated with poor sleep quality. Our results showed that both cohabitating and noncohabitating caregivers of PWD experienced overall poorer sleep quality compared to noncaregivers, indicating the deleterious effect of dementia caregiving on sleep quality, regardless of living arrangements. Given the high prevalence of poor sleep quality in family caregivers of PWD and the increasing awareness of the serious health consequences of poor-quality sleep, physicians should consider active sleep interventions to promote health and wellbeing not only for the dementia patients but also for family caregivers.

Stress and its contribution to the development of depression symptoms are reduced in caregivers of elderly with higher educational level

Caregivers of elderly people with neurodegenerative diseases are highly vulnerable to stressful situations and mood disorders due to their work conditions. Stress has been associated with an increased risk of developing depression, and studies have supported that caffeine consumption can act as an independent protective factor for disorder. This study investigated indexes of stress and depression symptoms in caregivers of the elderly with neurodegenerative diseases, their caffeine intake and the association between stress and depressive symptoms with the salivary biomarkers cortisol, nitric oxide and DNA damage. Participants (n = 81) were recruited from the community between July 2018 and April 2019. Stress was assessed using Lipp's Inventory of Stress Symptoms, and depressive symptoms were measured using the Hamilton Depressive Rating Scale. Participants provided a 72-hour recall of their diet to measure caffeine intake. Saliva samples were used to measure cortisol and nitric oxide. DNA damage was measured through micronuclei frequency after swabbing on the buccal mucosa. The majority of caregivers displayed stress and depressive symptoms. Stress was associated with educational level, tobacco use and total DNA damage. The indexes found in this population were not associated with caffeine intake or other salivary biomarkers, indicating that only some salivary molecules could be used as biomarkers for stress-related disorders. Caregivers of the elderly are exposed to stressful situations daily, however, we observed that educational level can reduce the psychological symptoms of stress and thus reduce the negative impact on quality of life.

Open-source Longitudinal Sleep Analysis From Accelerometer Data (DPSleep): Algorithm Development and Validation

BACKGROUND

Wearable devices are now widely available to collect continuous objective behavioral data from individuals and to measure sleep.

OBJECTIVE

This study aims to introduce a pipeline to infer sleep onset, duration, and quality from raw accelerometer data and then quantify the relationships between derived sleep metrics and other variables of interest.

METHODS

The pipeline released here for the deep phenotyping of sleep, as the DPSleep software package, uses a stepwise algorithm to detect missing data; within-individual, minute-based, spectral power percentiles of activity; and iterative, forward-and-backward-sliding windows to estimate the major Sleep Episode onset and offset. Software modules allow for manual quality control adjustment of the derived sleep features and correction for time zone changes. In this paper, we have illustrated the pipeline with data from participants studied for more than 200 days each.

RESULTS

Actigraphy-based measures of sleep duration were associated with self-reported sleep quality ratings. Simultaneous measures of smartphone use and GPS location data support the validity of the sleep timing inferences and reveal how phone measures of sleep timing can differ from actigraphy data.

CONCLUSIONS

We discuss the use of DPSleep in relation to other available sleep estimation approaches and provide example use cases that include multi-dimensional, deep longitudinal phenotyping, extended measurement of dynamics associated with mental illness, and the possibility of combining wearable actigraphy and personal electronic device data (eg, smartphones and tablets) to measure individual differences across a wide range of behavioral variations in health and disease. A new open-source pipeline for deep phenotyping of sleep, DPSleep, analyzes raw accelerometer data from wearable devices and estimates sleep onset and offset while allowing for manual quality control adjustments.

Sleep Quality in Young Adult Informal Caregivers: Understanding Psychological and Biological Processes

BACKGROUND

Providing informal care for a relative or friend with medical or mental needs can extol a physical burden on the caregiver, including impaired aspects of sleep quality such as suboptimal sleep duration, lengthened sleep latency, frequent awakenings, daytime sleepiness, and poor self-rated sleep quality. Diminished sleep quality can worsen the health in the caregiver, including dysregulation of hypothalamic-pituitary-adrenal axis (HPA) activity. Few studies have attempted to describe sleep in young adults who provide regular informal care. This study examines subjective and objective indicators of sleep quality and diurnal cortisol rhythms among young adult caregivers relative to non-caregiving peers. We expect that caregivers will exhibit poorer objective and subjective sleep quality and greater dysregulation in diurnal cortisol indices, than demographically similar non-caregivers, and that caregivers with poorer sleep will exhibit pronounced cortisol dysregulation.

METHODS

Participant self-reported sleep quality over the prior month via the Pittsburgh Sleep Quality Index and objective sleep quality was observed via wrist actigraph for three consecutive days. Diurnal salivary cortisol was also measured across the three days of actigraph monitoring.

RESULTS

Informal caregivers exhibited more self-reported sleep disturbance and greater sleep latency than non-caregivers, as well as more objectively measured sleep fragmentation. Caregivers with a shorter sleep duration were observed to have flatter diurnal cortisol slopes than caregivers with a relatively longer sleep duration.

CONCLUSIONS

Young adult caregivers appear to be at risk for impairment in sleep quality, which in turn might impact health through HPA axis dysregulation. Longitudinal research is needed to identify these relationships across time.

Accuracy of Actigraphy Compared to Concomitant Ambulatory Polysomnography in Narcolepsy and Other Sleep Disorders

Actigraphy provides longitudinal sleep data over multiple nights. It is a less expensive and less cumbersome method for measuring sleep than polysomnography. Studies assessing accuracy of actigraphy compared to ambulatory polysomnography in different sleep-disordered patients are rare. We aimed to compare the concordance between these methods in clinical setting. We included 290 clinical measurements of 281 sleep laboratory patients (mean age 37.9 years, 182 female). Concomitant ambulatory polysomnography and actigraphy were analyzed to determine the agreement in patients with obstructive sleep apnea, narcolepsy, periodic leg movement disorder, hypersomnia, other rarer sleep disorders, or no organic sleep disorder. Bland-Altman plots showed excellent accuracy, but poor precision in single night results between the two methods in the measurement of sleep time, sleep efficiency, and sleep latency. On average, actigraphy tended to overestimate sleep time by a negligible amount, −0.13 min, 95% confidence interval [−5.9, 5.6] min in the whole sample. Overestimation was largest, −12.8 [−25.1, −0.9] min, in patients with obstructive sleep apnea. By contrast, in patients with narcolepsy, actigraphy tended to underestimate sleep time by 24.3 [12.4, 36.1] min. As for sleep efficiency, actigraphy underestimated it by 0.18 [−0.99, 1.35] % and sleep latency by 11.0 [8.5, 13.6] min compared to polysomnography. We conclude that, in measuring sleep time, actigraphy is reasonably reliable and helpful to be used for a week or two to exclude insufficient sleep in patients with the suspicion of narcolepsy. However, the effectiveness of actigraphy in determining sleep seems to decrease in subjects with low sleep efficiencies.

Sleep Behaviors in Persons With Alzheimer's Disease: Associations With Caregiver Sleep and Affect

Poor sleep in persons with Alzheimer's disease (AD) is a common stressor for family caregivers. Retrospective reports support associations between sleep disturbance in persons with AD and worse caregiver mood; however, prospective associations between sleep in persons with AD and caregiver outcomes have not been studied. The current study determined associations between affect and sleep of persons with AD and their caregivers using daily diary data. Multilevel mediation models indicated that sleep in persons with AD is linked to caregiver affect; furthermore, these associations are mediated by sleep characteristics in caregivers and affect in persons with AD. Daily fluctuations in sleep behaviors in persons with AD-rather than average values-were most strongly associated with caregiver outcomes. Interventions to improve sleep in persons with AD may decrease their negative affect and improve caregiver mood.

Is Family Caregiving Associated With Inflammation or Compromised Immunity? A Meta-Analysis

BACKGROUND AND OBJECTIVES

Family caregiving stress has been widely reported to have negative effects on circulating biomarkers of immune system function and inflammation. Our goals were to systematically review this literature and conduct a meta-analysis on the extracted effects.

RESEARCH DESIGN AND METHODS

A systematic search of published studies comparing caregivers and noncaregivers on biomarkers measured from blood samples was conducted in the PubMed, Embase, and Cochrane databases. This search identified 2,582 articles and abstracts. After removing duplicative papers and studies not meeting inclusion criteria, 30 articles were identified that reported analyses on 86 relevant biomarkers from 1,848 caregivers and 3,640 noncaregivers.

RESULTS

Random-effects models revealed an overall effect size across all biomarkers of 0.164 SD units (d). A slightly larger overall effect (d = 0.188) was found for dementia caregivers only. Immune system comparisons yielded somewhat larger differences than inflammation comparisons. Most studies used small convenience samples, and effect sizes were larger for studies with moderate or high bias ratings than for studies with low bias ratings. No significant associations were found in studies that used population-based samples.

DISCUSSION AND IMPLICATIONS

Caregivers had small but significantly reduced immune system functioning and greater inflammation than noncaregivers, but associations were generally weak and of questionable clinical significance. The absence of clear associations from low bias studies and population-based studies underscores concerns with possible selection biases in many of the convenience samples. Population-based studies that assess biomarkers before and after the onset of caregiving might add much clarity to this literature.

Sleep Duration and Sleep Quality in Caregivers of Patients With Dementia: A Systematic Review and Meta-analysis

IMPORTANCE

In the United States, 16 million family caregivers provide long-term care for patients with dementia. Although one's physical, mental, and cognitive health depends on sleep, many caregivers experience chronic stress, and stress is typically associated with worse sleep quantity and quality.

OBJECTIVE

To quantify the extent, nature, and treatability of sleep problems in dementia caregivers.

DATA SOURCES

PubMed and Scopus databases were systematically searched for articles published through June 2018 using the following keywords: caregiver or spouse or caretaker AND sleep or circadian AND dementia or Alzheimer. Backward citation tracking was performed, and corresponding authors were contacted for additional data to conduct meta-analyses and pooled analyses.

STUDY SELECTION

Two reviewers independently screened 805 studies to identify those that reported sleep duration or sleep quality in caregivers of patients with dementia.

DATA EXTRACTION AND SYNTHESIS

Following the PRISMA guidelines, 2 reviewers independently extracted data from all studies and conducted National Heart, Lung, and Blood Institute study quality assessments. Meta-analyses with random-effects models were performed to evaluate sleep duration, sleep quality, and sleep interventions in dementia caregivers.

MAIN OUTCOMES AND MEASURES

Sleep quality and total sleep time were measured by polysomnography, actigraphy, and self-report.

RESULTS

Thirty-five studies were analyzed with data from 3268 caregivers (pooled mean age [SD of sample means], 63.48 [5.99] years; 76.7% female) were analyzed. Relative to age-matched control noncaregiver adults, caregivers had lower sleep durations akin to losing 2.42 to 3.50 hours each week (Hedges g = -0.29; 95% CI, -0.48 to -0.09; P = .01). Sleep quality was significantly lower in caregivers (Hedges g = -0.66; 95% CI, -0.89 to -0.42; P < .001), but caregivers who underwent sleep intervention trials had better sleep quality than caregivers who did not receive a sleep intervention (Hedges g = 0.35; 95% CI, 0.20-0.49; P < .001).

CONCLUSIONS AND RELEVANCE

Sleep debt is known to have cumulative associations with physical, mental, and cognitive health; therefore, poor sleep quality in dementia caregivers should be recognized and addressed. Although the caregiving role is stressful and cognitively demanding by its nature, better sleep quality was observed in caregivers who received low-cost behavioral interventions.

Informal caregiving and diurnal patterns of salivary cortisol: Results from the Whitehall II cohort study

The objective was to investigate the relationship between various aspects of informal caregiving and diurnal patterns of salivary cortisol, with special attention to the moderating effect of sex and work status. The study population was composed of 3727 men and women from the British Whitehall II study. Salivary cortisol was measured six times during a weekday. Aspects of caregiving included the relationship of caregiver to recipient, weekly hours of caregiving, and length of caregiving. Diurnal cortisol profiles were assessed using the cortisol awakening response (CAR) and diurnal cortisol slopes. Results showed that men, but not women, providing informal care had a blunted CAR compared with non-caregivers (P_Interaction = 0.03). Furthermore, we found a dose-response relationship showing that more weekly hours of informal care was associated with a more blunted CAR for men (P_trend = 0.03). Also, the blunted CAR for men was especially pronounced in short-term caregivers and those in paid work. In women, the steepest cortisol slope was seen among those in paid work who provided informal care (P_Interaction = 0.01). To conclude, we found different cortisol profiles in male and female informal caregivers. Male caregivers had a blunted CAR, which has previously been associated with chronic stress and burnout. Future research should investigate whether results are generalizable beyond UK citizens with a working history in the civil service.

Understanding Health-Related Quality of Life in Caregivers of Civilians and Service Members/Veterans With Traumatic Brain Injury: Establishing the Reliability and Validity of PROMIS Fatigue and Sleep Disturbance Item Banks

OBJECTIVE

To examine the reliability and validity of Patient-Reported Outcomes Measurement Information System (PROMIS) measures of sleep disturbance and fatigue in traumatic brain injury (TBI) caregivers and to determine the severity of fatigue and sleep disturbance in these caregivers.

DESIGN

Cross-sectional survey data collected through an online data capture platform.

SETTING

A total of 4 rehabilitation hospitals and Walter Reed National Military Medical Center.

PARTICIPANTS

Caregivers (N=560) of civilians (n=344) and service member/veterans (SMVs) (n=216) with TBI.

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

PROMIS sleep and fatigue measures administered as both computerized adaptive tests (CATs) and 4-item short forms (SFs).

RESULTS

For both samples, floor and ceiling effects for the PROMIS measures were low (<11%), internal consistency was very good (all α≥0.80), and test-retest reliability was acceptable (all r≥0.70 except for the fatigue CAT in the SMV sample r=0.63). Convergent validity was supported by moderate correlations between the PROMIS and related measures. Discriminant validity was supported by low correlations between PROMIS measures and measures of dissimilar constructs. PROMIS scores indicated significantly worse sleep and fatigue for those caring for someone with high levels versus low levels of impairment.

CONCLUSIONS

Findings support the reliability and validity of the PROMIS CAT and SF measures of sleep disturbance and fatigue in caregivers of civilians and SMVs with TBI.

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.

Impact of caregiving for older people and pro-inflammatory biomarkers among caregivers: a systematic review

INTRODUCTION

Evidence suggests that providing care for an older loved one may present a risk to the health of the caregiver. To understand the link between the psychosocial stress of caregiving and damage to the health of caregivers, numerous studies have assessed the presence of inflammatory biomarkers among caregivers. These biomarkers are measured to understand the relationships between the social stress of caregiving and the health of caregivers.

OBJECTIVE

To provide a complete summary of the current literature regarding the most clinically relevant pro-inflammatory biomarkers associated with caregiving.

METHODS

We searched articles in MEDLINE and EMBASE from January 1980 to 30 April 2016 for all studies that assessed biomarkers (cortisol, interleukin-6 and c-reactive protein) among caregivers of community-dwelling older persons. The quality of the selected studies was assessed by two reviewers using the STROBE or CONSORT checklist.

RESULTS

Twenty-four studies were included. Most of the studies were cross-sectional and focused on dementia caregiving. Increases in biomarkers were associated with problems such as disturbed sleep, burden or pain and caregiving characteristics, including daily stressors and the duration of caregiving. Cognitive-behavioural therapy and participation in leisure activities were associated with significantly lower levels of cortisol and IL-6, respectively.

DISCUSSION

We found little evidence concerning the association between caregiving status and biomarkers of stress and inflammation. We discuss potential sources of bias and suggest some directions for further research. This stress model can be expanded by taking into account the positive aspects of caregiving and the potential resources of caregivers.

Changes in Caregiving Status and Intensity and Sleep Characteristics Among High and Low Stressed Older Women

STUDY OBJECTIVES

To examine whether change in caregiving status and intensity among community-dwelling older women was associated with sleep characteristics at follow-up, and whether perceived stress modified these associations.

METHODS

The sample included 800 women aged 65 years or older who completed baseline and second follow-up interviews in the Caregiver-Study of Osteoporotic Fractures (Caregiver-SOF). Respondents were categorized into four groups based on change in caregiving status and intensity between the two time points: continuous noncaregivers, ceased caregivers, low-intensity caregivers (continuous caregivers with low/decreased intensity), and high-intensity caregivers (continuous caregivers with high/increased intensity or new caregivers). Perceived Stress Scale scores at the second follow-up were dichotomized into high versus low stress. Sleep outcomes at SOF Visit 8 (which overlapped with Caregiver-SOF second follow-up) included the Pittsburgh Sleep Quality Index total score; and actigraphy-measured total sleep time, sleep efficiency, wake after sleep onset, and sleep latency.

RESULTS

Multivariate-adjusted sleep characteristics did not differ significantly across caregiving groups. Among high-intensity caregivers, however, those with high stress levels had significantly longer wake after sleep onset (mean 82.3 minutes, 95% confidence interval = 70.9-93.7) than those with low stress levels (mean 65.4 minutes, 95% confidence interval = 55.2-75.7). No other sleep outcomes were modified by stress levels. Further, higher stress was significantly associated with worse Pittsburgh Sleep Quality Index scores, regardless of the caregiving group.

CONCLUSIONS

Overall, sleep characteristics did not differ among noncaregivers, ceased caregivers, or those with high-/low-intensity caregiving among older women. However, subgroups of caregivers may be vulnerable to developing sleep problems, particularly those with high stress levels.

Sleep disturbances in caregivers of patients with advanced cancer: A systematic review

OBJECTIVE

Sleep disturbances are a common issue for those who provide informal care to someone with a life-limiting condition. The negative consequences of poor sleep are well documented. The purpose of the present study was to determine the sleep patterns of caregivers of patients with advanced cancer.

METHOD

An extensive systematic review of studies reporting empirical sleep data was undertaken in 2015 in accordance with the PRISMA Statement. A total of eight electronic databases were searched, with no date restrictions imposed. Additionally, a search of the bibliographies of the studies identified during the electronic search was conducted. Search terms included: "sleep," "insomnia," "sleep disturbance," "circadian rhythm," "caregiver," "carer," "advanced cancer," "palliative cancer," and MESH suggestions. The inclusion criteria required studies to be in English and to report primary qualitative and/or quantitative research that examined sleep in caregivers of patients with advanced cancer. Unpublished studies, conference papers, and dissertations were excluded.

RESULTS

Overall, 10 studies met the inclusion criteria and were included in the review. Two major findings emerged from the data synthesis. First, at least 72% of caregivers reported moderate to severe sleep disturbance as measured by the Pittsburgh Sleep Quality Index. Second, objective measurement of caregivers' sleep identified that some caregivers experienced up to a 44% reduction in their total sleep time compared to the recommended eight hours.

SIGNIFICANCE OF RESULTS

Reduction in total sleep time appears to be the biggest issue facing caregivers' sleep. Future studies need to explore the specific factors that cause these sleep disturbances and thus help to identify interventions to optimize sleep.

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.

How Adult Caregiving Impacts Sleep: a Systematic Review

Sleep disturbance can contribute to negative health outcomes. However, sleep complaints have been under-recognized and undertreated in caregivers of ill family members. This systematic review describes the impact of family caregiving on sleep and summarizes factors associated with sleep disturbance in caregivers. A literature search using PubMed, MEDLINE, PsycINFO, and CINAHL databases yielded 22 relevant research articles on family caregivers of ill adults. Analyses revealed that up to 76% of caregivers reported poor sleep quality, and the proportion is considerably higher for female caregivers compared to male caregivers. Sleep measures indicated short sleep duration and frequent night awakenings. Characteristics of the care recipient, such as health status, and the caregiver's own health status and symptoms, such as depression, fatigue, and anxiety, were associated with sleep disturbance in caregivers. These factors may help clinicians identify caregivers at highest risk for developing sleep disturbance and guide the family toward additional support.

Assessing the daily stability of the cortisol awakening response in a controlled environment

Background

Levels of cortisol, the end product of the hypothalamic-pituitary-adrenal (HPA) axis, display a sharp increase immediately upon awakening, known as the cortisol awakening response (CAR). The daily stability of the CAR is potentially influenced by a range of methodological factors, including light exposure, participant adherence, sleep duration and nocturnal awakenings, making inferences about variations in the CAR difficult. The aim of the present study was to determine the daily stability of multiple measurement indices of the CAR in a highly-controlled sleep laboratory environment. A secondary aim was to examine the association between objective sleep continuity and sleep architecture, and the CAR.

Methods

The CAR was assessed in 15 healthy normal sleepers (seven male, eight female, M_age = 23.67 ± 3.49 years) on three consecutive weekday mornings. Sleep was measured objectively using polysomnography. Saliva samples were obtained at awakening, +15, +30, +45 and +60 min, from which multiple CAR measurement indices were derived: cortisol levels at each time point, awakening cortisol levels, the mean increase in cortisol levels (MnInc) and total cortisol secretion during the measurement period. Morning 2 and Morning 3 awakening cortisol levels, MnInc and total cortisol secretion were compared and the relationship between Night 1 and Night 2 objective measures of sleep continuity and architecture, and the subsequent CAR, was also assessed.

Results

There were no differences in cortisol levels at each time point, or total cortisol secretion during the CAR period, between Morning 2 and Morning 3. Awakening cortisol levels were lower, and the MnInc was higher, on Morning 3. Morning 2 and Morning 3 awakening levels (r = 0.77) and total cortisol secretion (r = 0.82), but not the magnitude of increase, were positively associated.

Conclusions

The stability of the CAR profile and total cortisol secretion, but not awakening cortisol levels or the magnitude of increase, was demonstrated across two consecutive mornings of measurement in a highly-controlled environment. Awakening cortisol levels, and the magnitude of increase, may be sensitive to differences in daily activities.

Electronic supplementary material

The online version of this article (doi:10.1186/s40359-016-0107-6) contains supplementary material, which is available to authorized users.

Positive affect and sleep in spousal Alzheimer caregivers: a longitudinal study

This article examines the longitudinal relation between positive affect (PA) and sleep in 126 spousal Alzheimer's disease caregivers. Caregivers underwent 4 yearly assessments for the Positive and Negative Affect Schedule, the self-rated Pittsburgh Sleep Quality Index, and actigraphy to objectify nighttime total sleep time, wake after sleep onset, and percentage of sleep. Increased levels of PA and a greater positivity (i.e., positive-to-negative affect) ratio were significantly associated with better subjective sleep over the entire study period. Yearly increases in PA-even when controlling for negative affect (NA)-and in the positivity ratio were also associated with better subjective sleep. PA and actigraphy measures showed no significant relations. Increased PA is longitudinally associated with better sleep in dementia caregivers largely independent of NA.

Physiological and functional consequences of caregiving for relatives with dementia

BACKGROUND

Chronic stress negatively affects health and well-being. A growing population of informal dementia caregivers experience chronic stress associated with extraordinary demands of caring for a relative with dementia. This review summarizes physiological and functional changes due to chronic dementia caregiver stress.

METHODS

A literature search for papers assessing effects of dementia caregiving was conducted focusing on publications evaluating differences between caregivers and non-caregivers in objective measures of health and cognition.

RESULTS

The review identified 37 studies describing data from 4,145 participants including 749 dementia caregivers and 3,396 non-caregiver peers. Objective outcome measures affected in dementia caregivers included markers of dyscoagulation, inflammation, and cell aging as well as measures of immune function, sleep, and cognition. Though diverse in designs, samples, and study quality, the majority of the studies indicated increased vulnerability of dementia caregivers to detrimental changes in health and cognition. Demographic and personality characteristics moderating or mediating effects of chronic stress in caregivers were also reviewed.

CONCLUSIONS

There is accumulating evidence that chronic dementia caregiver stress increases their vulnerability to disease and diminishes their ability to provide optimal care. Clinicians and society need to appreciate the extent of deleterious effects of chronic stress on dementia caregiver health.

Dementia caregivers' lived experience of sleep

PURPOSE

Poor sleep quality leads to sleep deficiency, an unmet public health problem that is especially acute in caregivers. The purpose of this study was to investigate the dementia caregiver's lived experience of sleep. The specific objectives were to (1) explore causes for poor sleep as identified by the caregiver, (2) gain knowledge about how the caregiver manages the sleep experience, and (3) gain an understanding of how caregivers perceive health promotion suggestions to improve sleep quality.

METHODS

This was a qualitative study using a phenomenological framework. In 3 focus groups, data were collected from 15 informal/family member caregivers of a person with dementia (PWD).

RESULTS

Three themes were identified in caregivers' descriptions of disruptions to their sleep quality: sleep quality fluctuating with the status of the PWD, a need for vigilance to safeguard the PWD at night, and worry about current and future events, which caused rumination. Caregivers did not receive formal help from healthcare providers but did participate in activities that promote good sleep. Caregivers identified barriers to health promotion activities, including lack of time, decreased energy, and additional costs for providing care for the PWD.

CONCLUSION

This research provides exemplars of caregivers' thoughts, preferences, values, and beliefs regarding their sleep experience in the context of caregiving. The caregiver's perspective should be taken into consideration when clinical nurse specialists provide evidence-based care. Clinical implications are provided.

Sleep characteristics of family caregivers of individuals with a primary malignant brain tumor

PURPOSE/OBJECTIVES

To describe the sleep characteristics of family caregivers of individuals with a primary malignant brain tumor (PMBT).

DESIGN

Cross-sectional, correlational design using baseline data from a longitudinal study.

SETTING

Neuro-oncology and neurosurgery clinics at an urban tertiary medical center in the United States.

SAMPLE

133 family caregivers recruited one to two months following diagnosis of family member's PMBT.

METHODS

Subjective and objective measures of sleep were obtained via self-report and the use of accelerometers (three nights).

MAIN RESEARCH VARIABLES

Sleep characteristics including sleep latency, total sleep time, wake after sleep onset, number of naps, number of arousals, sleep-wake cycle, and sleep quality.

FINDINGS

Sleep latency in caregivers was, on average, 35 minutes (SD = 34.5)-more than twice as long as the norm of 15 minutes (t[113]) = 6.18, p < 0.01). Caregivers averaged a total sleep time of 5 hours and 57 minutes (SD = 84.6), significantly less than the recommended 7 hours (t[113] = -8, p < 0.01), and were awake in the night 15% of the time, significantly more than the norm of 10% (t[111] = 5.84, p < 0.01). Caregivers aroused an average of 8.3 times during nocturnal sleep (SD = 3.5, range = 2-21), with about 32% reporting poor or very poor sleep quality.

CONCLUSIONS

Caregivers experienced sleep impairments that placed them at risk for poor mental and physical health, and may compromise their ability to continue in the caregiving role.

IMPLICATIONS FOR NURSING

Nurses need to assess sleep in caregivers of individuals with PMBT and implement interventions to improve sleep.

KNOWLEDGE TRANSLATION

Sleep deprivation is common in family caregivers during the early stages of care for individuals with a PMBT. A single-item sleep quality question could be an easy but valuable tool in assessing sleep disturbances in family caregivers of individuals with a PMBT. The health trajectory of family caregivers warrants further longitudinal study, in addition to the examination of the bidirectional relationship of health status of care recipients and their family caregiver.

Positive affect is associated with fewer sleep problems in older caregivers but not noncaregivers

PURPOSE OF THE STUDY

Older adults who are depressed or are caregivers experience more sleep problems, whereas recent studies suggest that adults with high positive affect (PA) have fewer sleep problems. This study examined whether the associations of PA and depressive symptoms with sleep problems differed between caregivers and noncaregivers.

DESIGN AND METHODS

Face-to-face interviews were conducted with 92 caregivers to a relative or friend with Alzheimer's disease or Parkinson's disease, and 137 noncaregivers aged 60 years and older (mean 73.8±7.9 years) from the Boston, Massachusetts, metropolitan area. Sleep problems were assessed using the Pittsburgh Sleep Quality Index (PSQI). Respondents were categorized as high PA (n = 122), low PA (n = 69), and depressive symptoms (n = 38) based on the Center for Epidemiologic Studies-Depression scale.

RESULTS

The mean PSQI score was 5.19 (SD = 3.26) and did not differ by caregiving status. In multivariable linear regression analyses among caregivers, those with high PA had significantly fewer sleep problems than their counterparts with low PA (adjusted mean PSQI score was 4.16 [SE = 0.50] vs. 5.69 [SE = 0.58], p = .05), whereas caregivers with depressive symptoms reported slightly more problems (adjusted mean 6.92 [SE = 0.80], p = .22). High PA and depressive symptoms were not associated with sleep problems among noncaregivers (adjusted mean PSQI scores were 4.88 [SE = 0.35], 5.38 [SE = 0.51], and 5.99 [SE = 0.73], respectively). Similar associations were found with PSQI scale components.

IMPLICATIONS

Results suggest that routine screening and interventions to increase PA may reduce sleep problems among older caregivers.

Sleep loss and its effects on health of family caregivers of individuals with primary malignant brain tumors

Sleep loss places caregivers at risk for poor health. Understanding correlates of sleep loss and relationships to health may enable improvement of health of caregivers of individuals with primary malignant brain tumors (PMBT). In this cross-sectional, descriptive study of 133 caregivers, relationships were examined between sleep loss and physical, mental, emotional, and social health at time of patient diagnosis. Sleep loss was not related to physical health. Shorter total sleep time was associated with greater fatigue and social support. Sleep quality was positively associated with quality of life. Further study is needed of the role of sleep loss in the PMBT caregiving trajectory and its long-term relationship with health outcomes.

Post-traumatic disorder symptoms and blunted diurnal cortisol production in partners of prostate cancer patients

Prostate cancer (PC) is the most common cancer diagnosed in men, and research suggests that coping with this illness can cause significant distress in patients as well as their partners. This study examined the relationship of caregiving for a partner with PC with diurnal cortisol output in women between the ages of 42 and 75 years old. Participants were women whose partners had PC (n = 19) and women who were in relationships with men with no diagnosed medical illness (n = 26). Women provided saliva samples (4 times per day over 3 days) in their natural environment. The Structured Clinical Interview for DSM-IV Axis-I Disorders was also conducted to assess for the presence of post-traumatic stress disorder (PTSD) and major depression. Partners of men with PC had lower daily cortisol output across the three days than controls, F(1,444.08) = 20.72, p<.001). They were also more likely to report PTSD symptoms with 68.4% of PC partners fulfilling criteria for sub-threshold PTSD as compared to 23.1% of controls (χ(2) = 11.30, p = .01). Mixed model analyses revealed that the presence of sub-threshold PTSD symptoms significantly predicted cortisol production, F(1,419.64) = 5.10, p<.01). Regardless of caregiver status, women who reported at least sub-threshold PTSD symptoms had lower cortisol production than those with no PTSD symptoms. Major depression did not explain differences in cortisol production between partners of PC patients and controls. Although these findings are preliminary, they highlight the importance of developing interventions aimed at reducing risk of psychopathology in partners of men with PC.

Differences in stress-related ratings between research center and home environments in dementia caregivers using ecological momentary assessment

BACKGROUND

Clinicians and researchers working with dementia caregivers typically assess caregiver stress in a clinic or research center, but caregivers' stress is rooted at home where they provide care. This study aimed to compare ratings of stress-related measures obtained in research settings and in the home using ecological momentary assessment (EMA).

METHODS

EMA of 18 caregivers (mean age 66.4 years ±7.8; 89% females) and 23 non-caregivers (mean age 66.4 years ±7.9; 87% females) was implemented using a personal digital assistant. Subjects rated their perceived stress, fatigue, coping with current situation, mindfulness, and situational demand once in the research center and again at 3-4 semi-random points during a day at home. The data from several assessments conducted at home were averaged for statistical analyses and compared with the data collected in the research center.

RESULTS

The testing environment had a differential effect on caregivers and non-caregivers for the ratings of perceived stress (p < 0.01) and situational demand (p = 0.01). When tested in the research center, ratings for all measures were similar between groups, but when tested at home, caregivers rated their perceived stress as higher than non-caregivers (p = 0.02). Overall, caregivers reported higher perceived stress at home than in the research center (p = 0.02), and non-caregivers reported greater situational demand in the research center than at home (p < 0.01).

CONCLUSIONS

The assessment method and environment affect stress-related outcomes. Evaluating participants in their natural environment provides a more sensitive measure of stress-related outcomes. EMA provides a convenient way to gather data when evaluating dementia caregivers.

Stress-related cognitive dysfunction in dementia caregivers

In a cross-sectional study, 31 dementia caregivers were compared to a group of 25 noncaregiving controls to evaluate whether the stress of being the primary caregiver of a person with dementia produces cognitive dysfunction. Cognitive differences were examined to evaluate the relationships between cognitive function and stress-related physiological and psychological measures to contribute information regarding its potential mechanism. The cognitive assessments were 2 measures of attention-executive function and 1 word list memory task. Physiological and self-rated stress-related measurements included cortisol, perceived stress, depression, self-efficacy, mindfulness, sleep quality, fatigue, and neuroticism. Caregivers performed worse than noncaregivers on the 2 attention tasks but not on the word list memory test. There was no interaction of caregiver status and age on cognitive performance. The caregivers and noncaregivers differed in morning salivary cortisol and most of the self-rated stress-related measures with the caregiver values reflecting greater stress. Of note, impaired sleep was the only potential mediator of the caregiver effect on cognitive performance in our small sample.