Predictors of Improvements in Mental Health From Mindfulness Meditation in Stressed Older Adults.

Context • The benefits of a mindfulness meditation (MM) intervention are most often evidenced by improvements in self-rated stress and mental health. Given the physiological complexity of the psychological stress system, it is likely that some people benefit significantly, whereas others do not. Clinicians and researchers could benefit from further exploration to determine which baseline factors can predict clinically significant improvements from MM. Objectives • The study intended to determine (1) whether the baseline measures for participants who significantly benefitted from MM training were different from the baseline measures of participants who did not, and (2) whether a classification analysis using a decision-tree, machine-learning approach could be useful in predicting which individuals would be most likely to improve. Design • The research team performed a secondary analysis of a previously completed randomized, controlled clinical trial. Setting • The study occurred at the Oregon Health & Science University (Portland, OR, USA) and in participants' homes. Participants • Participants were 134 stressed, generally healthy adults from the metropolitan area of Portland, Oregon, who were 50 to 85 y old. Intervention • Participants were randomly assigned either to a 6-wk MM intervention group or to a waitlist control group, who received the same MM intervention after the waitlist period. Outcome Measures • Outcome measures were assessed at baseline and at 2-mo follow-up intervals. A responder was defined as someone who demonstrated a moderate, clinically significant improvement on the mental health component (MHC) of the short-form health-related quality of life (SF-36) (ie, a change ≥4). The MHC had demonstrated the greatest effect size in the primary analysis of the previously mentioned randomized, controlled clinical trial. Potential predictors were demographic information and baseline measures related to stress and affect. Univariate statistical analyses were performed to compare the values of predictors in the responder and nonresponder groups. In addition, predictors were chosen for a classification analysis using a decision tree approach. Results • Of the 134 original participants, 121 completed the MM intervention. As defined previously, 61 were responders and 60 were nonresponders. Analyses of the baseline measures demonstrated significant differences between the 2 groups in several measures: (1) the positive and negative affect schedule negative subscale (PANAS-neg), (2) the SF-36-MHC, and (3) the SF-36 energy/fatigue, with clinically worse scores being associated with greater likelihood of being a responder. Disappointingly, the decision-tree analyses were unable to achieve a classification rate of better than 65%. Conclusions • The differences in predictor variables between responders and nonresponders to an MM intervention suggested that those with worse mental health at baseline were more likely to improve. Decision-tree analysis was unable to usefully predict who would respond to the intervention.

Do psychosocial predictors affect the following days' cortisol awakening response? Expanding the temporal frame with which to explore morning cortisol.

Much of the extant cortisol awakening response (CAR) literature posits that CAR is an anticipatory response to perceived demands later that same day. However, expanding and switching the temporal order of cortisol and psychosocial influences may motivate more flexible approaches to understanding the dynamic relationship between mind and body, including cumulative strain on the HPA axis. This study was novel because we used two models to explore the effects of one day's emotion regulation and cortisol levels on cortisol and CAR the following day in 100 mildly stressed adults aged 50-81 years old, which contrasts with the more common CAR-anticipatory-response design. In the first model, High negative-affect-variation on day 1 predicted a higher risk of having a flat CAR the next day, relative to the moderate-affect-variation group (RR = 10.10, p < .05). In the second model, higher bedtime cortisol on day 1 was positively associated with waking cortisol (ß = .293, p < .01) and flatter CAR slopes on day 2 (ß = -.422, p < .001). These results show that morning cortisol intercepts and slopes may be associated with previous days' affect variability and levels of bedtime cortisol. These results also suggest that anticipation of demands may extend to the previous day, rather than just the morning of the demand, indicating a broader temporal framework for the study of CAR.

Impulsivity and Stress Response in Nondependent Smokers (Tobacco Chippers) in Comparison to Heavy Smokers and Nonsmokers.

INTRODUCTION: Tobacco chippers are light smokers with stable patterns of smoking that exhibit lower nicotine dependence severity than heavy smokers. Chippers may provide valuable information about the factors influencing drug dependence. Impulsivity and stress are two factors known to influence smoking. By comparing nondependent smokers (tobacco chippers, n = 25) to dependent smokers (heavy smokers, n = 23) and nonsmokers (n = 25), this study examines the relationship between nicotine dependence, impulsivity, chronic stress, and stress reactivity. METHODS: A total of 73 adult participants completed a study visit that included questionnaires to measure nicotine dependence, chronic stress, personality, affect, withdrawal, and craving. Impulsivity was measured with the delay discounting task and the flanker task. Stress reactivity was assessed by monitoring respiration, heart rate, and salivary cortisol during performance of a titrated Stroop task. Effects of acute stress on affect and craving were examined. RESULTS: Tobacco chippers were as impulsive as heavy smokers on the delay discounting task but no different from nonsmokers on the flanker task. Heavy smokers reported higher perceived stress than chippers and nonsmokers. Perceived stress was a significant predictor of discounting only in heavy smokers. Acute stress induced changes in respiration, heart rate, and heart rate variability. Craving and negative affect increased after stress in both smoking groups, but craving was associated with affect only in chippers. CONCLUSIONS: Tobacco chippers do not differ from heavy smokers in impulsivity, but do differ in perceived stress. One's perception and experience of stress might be associated to nicotine dependence resistance and could inform smoking cessation treatments. IMPLICATIONS: By examining impulsivity, chronic stress, and stress reactivity in nondependent smokers (tobacco chippers) compared to dependent smokers and nonsmokers, this study contributes to the understanding of nicotine addiction and informs smoking cessation programs.

Internet-based Mindfulness Meditation for Cognition and Mood in Older Adults: A Pilot Study.

CONTEXT: Older adults are at risk for greater chronic stress and cognitive decline. Training in mindfulness meditation (MM) may help reduce stress and, thus, cognitive decline in older adults, but little research has explored that hypothesis. OBJECTIVE: The current study's primary aim was to evaluate the feasibility and acceptability for use by older adults of the Internet Mindfulness Meditation Intervention (IMMI), a program that had been developed by the research team, as well as of an Internet-based health-and-wellness education program, the control. The secondary aim was to collect preliminary pre- and postintervention data on mood and cognitive function. DESIGN: The study was a randomized, controlled trial (RCT), a pilot study, with participants randomized either to the meditation group or the education group. SETTING: Participants obtained access to the programs from their homes, and the baseline and endpoint assessments occurred in their homes as well. PARTICIPANTS: Older adults aged 65-90 y were recruited from the Portland, OR, metropolitan area. Twenty-one people enrolled in the study. INTERVENTION: Participants in both groups took part in a 1-h online session each week for 6 wk, with 30 min of daily home practice. OUTCOME MEASURES: Feasibility and acceptability were assessed through measures of adherence to the protocol and a client satisfaction questionnaire. Mood and cognitive outcomes were also evaluated before and after the interventions. RESULTS: Sixteen participants completed the study, 8 in each group, and 5 dropped out, for a 76% completion rate. Participants' mean age was 76.2 y; 88% were Caucasian, and 50% were female. Acceptability was high for the interventions, based on above-average scores on the client satisfaction questionnaire. The IMMI participants completed (1) 4.25 ± 2.4 sessions, with a range of 0-6; (2) 604 ± 506 home-practice minutes, with a range 0-1432; and (3) 21.3 ± 15.5 d of practice, with a range of 0-46. The education group completed (1) 4.75 ± 1.8 sessions, with a range of 2-6; (2) 873 ± 395 home-practice minutes, with a range of 327-1524; and (3) 25.6 d of practice, with a range of 11-35. The intervention and control formats were both feasible, and the control group was appropriate. As expected due to the pilot nature of the study, no differences existed between groups for the mood or cognitive outcomes. CONCLUSIONS: Administering interventions via the Internet to older adults is feasible. The 2 interventions were acceptable to participants and equal with regard to perceived credibility and acceptability. Future RCTs are planned to evaluate the clinical efficacy of the 2 interventions.

Mechanistic Pathways of Mindfulness Meditation in Combat Veterans With Posttraumatic Stress Disorder.

OBJECTIVE: This study's objective was to evaluate the effect of two common components of meditation (mindfulness and slow breathing) on potential mechanistic pathways. METHODS: A total of 102 combat veterans with posttraumatic stress disorder (PTSD) were randomized to (a) the body scan mindfulness meditation (MM), (b) slow breathing (SB) with a biofeedback device, (c) mindful awareness of the breath with an intention to slow the breath (MM+SB), or (d) sitting quietly (SQ). Participants had 6 weekly one-on-one sessions with 20 minutes of daily home practice. The mechanistic pathways and measures were as follows: (a) autonomic nervous system (hyperarousal symptoms, heart rate [HR], and heart rate variability [HRV]); (b) frontal cortex activity (attentional network task [ANT] conflict effect and event-related negativity and intrusive thoughts); and (c) hypothalamic-pituitary-adrenal axis (awakening cortisol). PTSD measures were also evaluated. RESULTS: Meditation participants had significant but modest within-group improvement in PTSD and related symptoms, although there were no effects between groups. Perceived impression of PTSD symptom improvement was greater in the meditation arms compared with controls. Resting respiration decreased in the meditation arms compared with SQ. For the mechanistic pathways, (a) subjective hyperarousal symptoms improved within-group (but not between groups) for MM, MM+SB, and SQ, while HR and HRV did not; (b) intrusive thoughts decreased in MM compared with MM+SB and SB, while the ANT measures did not change; and (c) MM had lower awakening cortisol within-group (but not between groups). CONCLUSION: Treatment effects were mostly specific to self-report rather than physiological measures. Continued research is needed to further evaluate mindfulness meditation's mechanism in people with PTSD.

Teaching mindfulness meditation to adults with severe speech and physical impairments: An exploratory study.

People with severe speech and physical impairments may benefit from mindfulness meditation training because it has the potential to enhance their ability to cope with anxiety, depression and pain and improve their attentional capacity to use brain-computer interface systems. Seven adults with severe speech and physical impairments (SSPI) - defined as speech that is understood less than 25% of the time and/or severely reduced hand function for writing/typing - participated in this exploratory, uncontrolled intervention study. The objectives were to describe the development and implementation of a six-week mindfulness meditation intervention and to identify feasible outcome measures in this population. The weekly intervention was delivered by an instructor in the participant's home, and participants were encouraged to practise daily using audio recordings. The objective adherence to home practice was 10.2 minutes per day. Exploratory outcome measures were an n-back working memory task, the Attention Process Training-II Attention Questionnaire, the Pittsburgh Sleep Quality Index, the Perceived Stress Scale, the Positive and Negative Affect Schedule, and a qualitative feedback survey. There were no statistically significant pre-post results in this small sample, yet administration of the measures proved feasible, and qualitative reports were overall positive. Obstacles to teaching mindfulness meditation to persons with SSPI are reported, and solutions are proposed.

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.

Contributions of loneliness to cognitive impairment and dementia in older adults are independent of other risk factors and Alzheimer's pathology: a narrative review.

Loneliness significantly contributes to cognitive impairment and dementia in older adults. Loneliness is a distressing feeling resulting from a perceived lack of social connection (i.e., a discrepancy between desired and actual social relationships), while social isolation is a related term that can be defined by number and type of social relationships. Importantly, loneliness is distinct from social isolation in that it is associated with a distressing self-perception. The primary focus of this narrative review is the impact of chronic loneliness on cognitive impairment and dementia among older adults. Loneliness has a significant association with many factors that are related to worse cognition, and therefore we include discussion on health, mental health, as well as the physiological effects of loneliness, neuropathology, and potential treatments. Loneliness has been shown to be related to development of dementia with a hazard ratio (HR) risk comparable to having a single APOE4 gene. The relationship of dementia to loneliness appears to be at least partially independent of other known dementia risk factors that are possibly associated with loneliness, such as depression, educational status, social isolation, and physical activity. Episodic memory is not consistently impacted by loneliness, which would be more typically impaired if the mild cognitive impairment (MCI) or dementia was due to Alzheimer's disease (AD) pathology. In addition, the several longitudinal studies that included neuropathology showed no evidence for a relationship between loneliness and AD neuropathology. Loneliness may decrease resilience, or produce greater cognitive change associated with the same level of AD neuropathology. Intervention strategies to decrease loneliness in older adults have been developed but need to consider key treatment targets beyond social isolation. Loneliness needs to be assessed in all studies of cognitive decline in elders, since it significantly contributes to the variance of cognitive function. It will be useful to better define the underlying mechanism of loneliness effects on cognition to determine if it is similar to other psychological factors related to excessive stress reactivity, such as neuroticism or even depression, which are also associated with cognitive decline. It is important from a health perspective to develop better strategies to decrease loneliness in older adults.

Effect of expectancy and personality on cortical excitability in Parkinson's disease.

Our previous studies in Parkinson's disease have shown that both levodopa and expectancy of receiving levodopa reduce cortical excitability. We designed this study to evaluate how degree of expectancy and other individual factors modulate placebo response in Parkinson's patients. Twenty-six Parkinson's patients were randomized to 1 of 3 groups: 0%, 50%, and 100% expectancy of receiving levodopa. All subjects received placebo regardless of expectancy group. Subjects completed the NEO-Five Factor Inventory, General Perceived Self-Efficacy Scale, and Perceived Stress Scale. Cortical excitability was measured by the amplitude of motor-evoked potential (MEP) evoked by transcranial magnetic stimulation. Objective physical fatigue of extensor carpi radialis before and after placebo levodopa was also measured. Responders were defined as subjects who responded to the placebo levodopa with a decrease in MEP. Degree of expectancy had a significant effect on MEP response (P < .05). Subjects in the 50% and 100% expectancy groups responded with a decrease in MEP, whereas those in the 0% expectancy group responded with an increase in MEP (P < .05). Responders tended to be more open to experience than nonresponders. There were no significant changes in objective physical fatigue between the expectancy groups or between responders and nonresponders. Expectancy is associated with changes in cortical excitability. Further studies are needed to examine the relationship between personality and placebo effect in Parkinson's patients. © 2013 Movement Disorder Society.

Salivary cortisol lower in posttraumatic stress disorder.

Altered cortisol has been demonstrated to be lower in those with posttraumatic stress disorder (PTSD) in most studies. This cross-sectional study evaluated salivary cortisol at waking and 30 minutes after, and at bedtime in 51 combat veterans with PTSD compared to 20 veterans without PTSD. It also examined the relationship of cortisol to PTSD symptoms using 2 classifications: the Diagnostic and Statistical Manual of Mental Disorders (4th ed., DSM-IV; American Psychiatric Association, 1994) and the more recent 4-factor classification proposed for DSM-5. The PTSD group had lower cortisol values than the control group, F(6, 69) = 3.35, p = .006. This significance did not change when adding age, body mass index, smoking, medications affecting cortisol, awakening time, sleep duration, season, depression, perceived stress, service era, combat exposure, and lifetime trauma to the model. Post hoc analyses revealed that the PTSD group had lower area-under-the-curve ground and waking, 30 min, and bedtime values; the cortisol awakening response and area-under-the-curve increase were not different between groups. The 4-factor avoidance PTSD symptom cluster was associated with cortisol, but not the other symptom clusters. This study supports the finding that cortisol is lower in people with PTSD.

Peak high-frequency HRV and peak alpha frequency higher in PTSD.

Posttraumatic stress disorder (PTSD) is difficult to treat and current PTSD treatments are not effective for all people. Despite limited evidence for its efficacy, some clinicians have implemented biofeedback for PTSD treatment. As a first step in constructing an effective biofeedback treatment program, we assessed respiration, electroencephalography (EEG) and heart rate variability (HRV) as potential biofeedback parameters for a future clinical trial. This cross-sectional study included 86 veterans; 59 with and 27 without PTSD. Data were collected on EEG measures, HRV, and respiration rate during an attentive resting state. Measures were analyzed to assess sensitivity to PTSD status and the relationship to PTSD symptoms. Peak alpha frequency was higher in the PTSD group (F(1,84) = 6.14, p = 0.01). Peak high-frequency HRV was lower in the PTSD group (F(2,78) = 26.5, p < 0.00005) when adjusting for respiration rate. All other EEG and HRV measures and respiration were not different between groups. Peak high-frequency HRV and peak alpha frequency are sensitive to PTSD status and may be potential biofeedback parameters for future PTSD clinical trials.

Patterns of Respiration Rate Reactivity in Response to a Cognitive Stressor Associate With Self-Reported Mental Health Outcomes.

Many studies have examined physiological responses to acute stress in healthy and clinical populations. Some have documented exaggerated physiological stress reactivity in response to acute stress, while others have reported blunted physiological stress reactivity. Although the literature is conflicted, the relationship between abnormal physiological stress reactivity and negative outcomes is well-established. However, past research has neglected a critical aspect of physiological stress response - respiration - and it is unclear whether differences in respiration rate responses to acute stress are related to health outcomes. This secondary cross-sectional analysis explored differences in outcomes between three subgroups: blunted, moderate, and exaggerated respiration rate reactivity to an acute stress task. In a sample of at least mildly-stressed older adults (n = 55), we found that perceived stress (b = -7.63; p = .004) and depression (b = -9.13; p = .007) were significantly lower in the moderate reactivity group compared to the high reactivity group, and that self-reported mindfulness (b = 10.96; p = .008) was significantly lower in the moderate reactivity group as compared to the low reactivity group. Across outcomes, participants in the moderate range of physiological reactivity showed less negative and more positive psychological attributes and better health outcomes, while the blunted subgroup demonstrated more negative and less positive psychological attributes and worse health outcomes overall, when compared to the exaggerated and moderate groups. This study extends the literature by adding respiration to markers of acute physiological stress reactivity and demonstrating the effects of blunted respiration reactivity on negative psychological attributes and health outcomes.

Protocol for an exploratory, randomised, single-blind clinical trial of aerobic exercise to promote remyelination in multiple sclerosis.

INTRODUCTION: There is an urgent need for remyelinating therapies that restore function in people with multiple sclerosis (pwMS). Aerobic exercise is a promising remyelinating strategy because it promotes remyelination in animal models both independently and synergistically with medications. Here, in this study, we present an innovative, randomised, single-blind, clinical trial designed to explore: the relationship between demyelination and mobility (part 1), and if 24 weeks of aerobic exercise promotes remyelination in pwMS (part 2). METHODS AND ANALYSIS: Sedentary participants (n=60; aged 18-64 years) with stable MS will undergo a baseline visit with the following outcomes to assess associations between demyelination and mobility (part 1): spinal cord demyelination (somatosensory-evoked potentials, SSEPs), mobility (6-Minute Timed Walk, Timed 25-Foot Walk, Timed Up and Go, 9-Hole Peg Test) and patient-reported outcomes (PROs). After baseline testing, participants with significantly prolonged SSEP latency will advance to the clinical exercise trial (part 2) and will be randomised 1:1 to active or control conditions for 24 weeks. The active condition will be aerobic stationary cycling three times per week with graded virtual supervision. The control condition will be monthly virtual MS symptom education groups (six sessions). SSEP latency (remyelination endpoint), mobility outcomes and PROs will be measured at 12 and 24 weeks in all clinical trial participants. A subset of 11 active and 11 control participants will undergo a brain MRI with quantitative T1 myelin water fraction at baseline and 24 weeks (exploratory remyelination endpoint). ETHICS AND DISSEMINATION: Ethical approval was obtained from the Oregon Health & Science University Institutional Review Board (#21045). Dissemination of findings will include peer-reviewed publications, conference presentations and media releases. The proposed study will inform the feasibility, study design and sample size for a fully powered clinical trial of aerobic exercise to promote remyelination in pwMS. TRIAL REGISTRATION NUMBER: NCT04539002.

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.

Target-Related Alpha Attenuation in a Brain-Computer Interface Rapid Serial Visual Presentation Calibration.

This study evaluated the feasibility of using occipitoparietal alpha activity to drive target/non-target classification in a brain-computer interface (BCI) for communication. EEG data were collected from 12 participants who completed BCI Rapid Serial Visual Presentation (RSVP) calibrations at two different presentation rates: 1 and 4 Hz. Attention-related changes in posterior alpha activity were compared to two event-related potentials (ERPs): N200 and P300. Machine learning approaches evaluated target/non-target classification accuracy using alpha activity. Results indicated significant alpha attenuation following target letters at both 1 and 4 Hz presentation rates, though this effect was significantly reduced in the 4 Hz condition. Target-related alpha attenuation was not correlated with coincident N200 or P300 target effects. Classification using posterior alpha activity was above chance and benefitted from individualized tuning procedures. These findings suggest that target-related posterior alpha attenuation is detectable in a BCI RSVP calibration and that this signal could be leveraged in machine learning algorithms used for RSVP or comparable attention-based BCI paradigms.

Reliability and validity of food frequency questionnaire and nutrient biomarkers in elders with and without mild cognitive impairment.

INTRODUCTION: There is great interest in the nutritional strategies for the prevention of age-related cognitive decline, yet the best methods for nutritional assessment in the populations at risk for dementia are still evolving. Our study objective was to examine the reliability and validity of the 2 common nutritional assessments (plasma nutrient biomarkers and Food Frequency Questionnaire) in the people at risk for dementia. METHODS: Thirty-eight elders, half with amnestic-mild cognitive impairment were recruited. Nutritional assessments were collected together at the baseline and again at 1 month. Intraclass and Pearson correlation coefficients quantified reliability and validity. RESULTS: Twenty-six nutrients were examined. The reliability was very good or better for 77% (20/26, intraclass correlation coefficients or ICC ≥0.75) of the plasma nutrient biomarkers and for 88% of the food frequency questionnaires (FFQ) estimates. Twelve of the nutrient biomarkers were as reliable as the commonly measured plasma cholesterol (ICC≥0.92). FFQ and plasma long-chain fatty acids (docosahexaenoic acid, r=0.39, eicosapentaenoic acid, r=0.39) and carotenoids (α-carotene, r=0.49; lutein + zeaxanthin, r=0.48; ß-carotene, r=0.43; ß-cryptoxanthin, r=0.41) were correlated, but these significant correlations were present only in non-impaired elders. CONCLUSION: The reliability and validity of the FFQ and nutrient biomarkers vary according to the nutrient of interest. Memory deficit attenuates validity and inflates reliability of FFQ reports. Many plasma nutrient biomarkers have very good reliability over 1-month, regardless of memory state. This objective method can circumvent sources of error seen in other less direct and subjective methods of nutritional assessment.

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.

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

Findings from previous research assessing sleep quality in caregivers are inconsistent due to differences in sleep assessment methods. This study evaluated sleep in dementia caregivers using a comprehensive sleep assessment utilizing an ambulatory polysomnography (PSG) device. A total of 20 caregivers and 20 noncaregivers rated their perceived sleep quality, stress, and depressive symptoms; provided samples of cortisol and inflammatory biomarkers; and completed an objective sleep assessment using a portable PSG device. Caregivers reported greater perceived stress than noncaregivers. Next, the groups had different sleep architecture: caregivers spent less proportion of their sleep in restorative sleep stages compared to noncaregivers. Further, levels of C-reactive protein and awakening salivary cortisol were greater in caregivers than in noncaregivers, and these measures were related to sleep quality. Our findings indicate that sleep disruption is a significant concomitant of caregiving and may affect caregiver's health. Sleep quality of caregivers might be a useful target for a clinical intervention.

Differential impact of mindfulness practices on aggression among law enforcement officers.

OBJECTIVES: Home-based mindfulness practice is a common component of formal mindfulness training (MT) protocols. Obtaining objective data from home-based mindfulness practice is challenging. Interpreting associations between home-based mindfulness practice and clinically impactful outcomes is complicated given the variability in recommendations in length, frequency, and type of practice. In this exploratory study, adherence to home-based practices of Mindfulness-Based Resilience Training (MBRT) was studied in order to evaluate associations with clinical outcomes. METHODS: Home practices from 24 (92% male, non-Hispanic white, aged M = 43.20 years) law enforcement officers (LEOs) from the urban Pacific Northwest enrolled in a feasibility and efficacy trial of MBRT were studied using an objective tracking device and self-report data. Outcomes included adherence to home-based mindfulness practices and self-reported aggression. RESULTS: Participants completed 59.12% of the frequency amount of practice assigned in the MBRT curriculum. Frequency of practice was associated with decreased aggression, adjusted R 2 = .41, F(3,23) = 6.14, p = .004. Duration of practice also predicted decreased aggression, adjusted R 2 = .33, F(3,23) = 4.76, p = .011. CONCLUSIONS: Home-based MBRT practices for LEOs, even at low rates of adherence, may reduce aggression. MTs may show beneficial effects for other populations presented with challenges to engage in regular MT practices.

Ascorbic acid and rates of cognitive decline in Alzheimer's disease.

The brain maintains high levels of ascorbic acid (AA) despite a concentration gradient favoring diffusion from brain to peripheral tissues. Dietary antioxidants, including AA, appear to modify the risk of Alzheimer's disease (AD). The objective of this study was to test the hypothesis that neurodegeneration in AD is modified by brain levels of AA. Thirty-two patients with mild to moderate AD participated in a biomarker study involving standardized clinical assessments over one year. Cerebrospinal fluid (CSF) and serum were collected at baseline for AA and albumin content. Cognitive measures were collected at baseline and one year. CSF and plasma AA failed to predict cognitive decline independently, however, CSF: plasma AA ratio did. After adding CSF Albumin Index (an established marker of blood-brain barrier integrity) to the regression models the effect of CSF: plasma AA ratio as a predictor of cognitive decline was weakened. CSF: plasma AA ratio predicts rate of decline in AD. This relationship may indicate that the CSF: plasma AA ratio is an index of AA availability to the brain or may be an artifact of a relationship between blood-brain barrier impairment and neurodegeneration.