Leisure activities, caregiving demands and catecholamine levels in dementia caregivers

This study examined whether satisfaction from leisure activities moderates the relationship between caregiving demands (i.e., hours per day spent caring for a spouse with dementia) and resting levels of the catecholamines norepinephrine (NE) and epinephrine (EPI). Spousal caregivers (n?=?107; mean age?=?73.95?±?8.12 years) were assessed in home for plasma levels of NE and EPI, amount of care provided, and leisure satisfaction. Regression was used to determine whether leisure satisfaction moderated the relationship between hours providing care per day and catecholamine levels. A significant interaction was found between hours caregiving and leisure satisfaction for NE, but not for EPI. Post?hoc regressions were conducted for both NE and EPI. At low leisure satisfaction, time spent caring for a spouse was positively associated with plasma NE (β?=?0.41; p?=?0.005) and EPI (β?=?0.44; p?=?0.003). In contrast, at high levels of satisfaction, time caregiving was not significantly associated with plasma NE (β?=?-0.08; p?=?0.57) or EPI (β?=?0.23; p?=?0.12). These findings suggest that leisure satisfaction may protect caregivers from increases in catecholamines, which have been implicated in cardiovascular risk. Further support for these findings may impact psychological treatments for distressed caregivers.     

Functional interactions between the nucleus tractus solitarius (NTS) and nucleus accumbens shell in modulating memory for arousing experiences

The shell division of the nucleus accumbens receives noradrenergic input from neurons in the nucleus of the solitary tract (NTS) that transmit information regarding fluctuations in peripheral hormonal and autonomic activity. Accumbens shell neurons also receive converging inputs from limbic areas such as the hippocampus and amygdala that process newly acquired information. However, few studies have explored whether peripheral information regarding changes in emotional arousal contributes to memory processing in the accumbens. The beneficial effects on memory produced by emotional arousal and the corresponding activation of NTS neurons may be mediated through influences on neuronal activity in the accumbens shell during memory encoding. To explore this putative relationship, Experiment 1 examined interactions between the NTS and the accumbens shell in modulating memory for responses acquired after footshock training in a water-motivated inhibitory avoidance task. Memory for the noxious shock was significantly improved by posttraining excitation of noradrenergic NTS neurons. The enhanced retention produced by activating NTS neurons was attenuated by suppressing neuronal activity in the accumbens shell with bupivacaine (0.25%/0.5 microl). Experiment 2 examined the direct involvement of accumbens shell noradrenergic activation in the modulation of memory for psychologically arousing events such as a reduction in perceived reward value. Noradrenergic activation of the accumbens shell with phenylephrine (1.0 microg/0.5 microl) produced an enhancement in memory for the frustrating experience relative to control injections as evidenced by runway performance on an extended seven-day retention test. These findings demonstrate a functional relationship between NTS neurons and the accumbens shell in modulating memory following physiological arousal and identifies a role of norepinephrine in modulating synaptic activity in the accumbens shell to facilitate this process.     

A randomized clinical trial of Behavioral Activation (BA) therapy for improving psychological and physical health in dementia caregivers: Results of the Pleasant Events Program (PEP)

Dementia caregiving is associated with elevations in depressive symptoms and increased risk for cardiovascular diseases (CVD). This study evaluated the efficacy of the Pleasant Events Program (PEP), a 6-week Behavioral Activation intervention designed to reduce CVD risk and depressive symptoms in caregivers. One hundred dementia family caregivers were randomized to either the 6-week PEP intervention (N = 49) or a time-equivalent Information-Support (IS) control condition (N = 51). Assessments were completed pre- and post-intervention and at 1-year follow-up. Biological assessments included CVD risk markers Interleukin-6 (IL-6) and D-dimer. Psychosocial outcomes included depressive symptoms, positive affect, and negative affect. Participants receiving the PEP intervention had significantly greater reductions in IL-6 (p = .040), depressive symptoms (p = .039), and negative affect (p = .021) from pre- to post-treatment. For IL-6, clinically significant improvement was observed in 20.0% of PEP participants and 6.5% of IS participants. For depressive symptoms, clinically significant improvement was found for 32.7% of PEP vs 11.8% of IS participants. Group differences in change from baseline to 1-year follow-up were non-significant for all outcomes. The PEP program decreased depression and improved a measure of physiological health in older dementia caregivers. Future research should examine the efficacy of PEP for improving other CVD biomarkers and seek to sustain the intervention's effects.     

Influence of caregiver burden on the association between daily fluctuations in pleasant activities and mood: A daily diary analysis

Much research has focused on behavioral activation and its effect on depression, but less is known about the effects of leisure activities on the two distinct affective domains of depression: positive affect (PA) and negative affect (NA). Furthermore, individual factors (i.e., stress level) may moderate the impact of behavioral activation on affect. The present study utilized a daily diary approach to examine the moderating effect of stress on the relationship between leisure satisfaction and both PA and NA. Twenty-five dementia caregivers completed activity and affect measures four times daily for 14 days. Results were analyzed using multilevel modeling, an approach that considers intra-individual differences in activity and affect over time. Results supported the hypothesis that caregivers with higher burden display a stronger association between leisure satisfaction and affect than caregivers with lower burden. Specifically, caregivers with higher burden had a stronger positive relationship between leisure satisfaction and PA and a stronger negative relationship between leisure satisfaction and NA. These findings suggest that screening caregivers for level of burden may help identify those most likely to benefit from behavioral interventions.     

Leisure activities,caregiving demands and catecholamine levels in dementia caregivers

This study examined whether satisfaction from leisure activities moderates the relationship between caregiving demands (i.e., hours per day spent caring for a spouse with dementia) and resting levels of the catecholamines norepinephrine (NE) and epinephrine (EPI). Spousal caregivers (n?=?107; mean age?=?73.95?±?8.12 years) were assessed in home for plasma levels of NE and EPI, amount of care provided, and leisure satisfaction. Regression was used to determine whether leisure satisfaction moderated the relationship between hours providing care per day and catecholamine levels. A significant interaction was found between hours caregiving and leisure satisfaction for NE, but not for EPI. Post hoc regressions were conducted for both NE and EPI. At low leisure satisfaction, time spent caring for a spouse was positively associated with plasma NE (β?=?0.41; p?=?0.005) and EPI (β?=?0.44; p?=?0.003). In contrast, at high levels of satisfaction, time caregiving was not significantly associated with plasma NE (β?=?–0.08; p?=?0.57) or EPI (β?=?0.23; p?=?0.12). These findings suggest that leisure satisfaction may protect caregivers from increases in catecholamines, which have been implicated in cardiovascular risk. Further support for these findings may impact psychological treatments for distressed caregivers.     

Relationship between chronic stress and carotid intima-media thickness (IMT) in elderly Alzheimer's disease caregivers

The stress associated with providing care for a spouse diagnosed with Alzheimer's disease can have adverse effects on cardiovascular health. One potential explanation is that chronic caregiving stress may contribute to the development of atherosclerosis. The purpose of this study was to determine whether the duration that one has provided care is associated with the degree of atherosclerotic burden, as measured by carotid artery intima-media thickness (IMT). One hundred and ten Alzheimer caregivers [mean age 74?±?8 (SD) years, 69% female] underwent in-home assessment of carotid artery IMT via B-mode ultrasonography. Data regarding medical history, blood pressure, and multiple indicators of caregiving stress were also collected. Multiple regression indicated that duration of care was positively associated with IMT measured in the internal/bifurcation segments of the carotid artery (β?=?0.202, p?=?0.044) independent of risk factors such as age, gender, body mass index, smoking history, sleep quality, hypertension status, and caregiving stressors. Duration of care was positively associated with IMT in the common carotid artery, but the relationship was not significant. These findings provide more evidence of the link between chronic caregiving stress and cardiovascular disease and indicate that enduring the experience of caregiving over a period of years might be associated with atherosclerotic burden.     

The Effect of Stress on Spontaneous Nest Leaving Behavior in the Mouse: An Improved Model of Stress-Induced Behavioral Pathology

The present experiments were conducted to develop a more sensitive and reliable model of stress-induced behavioral pathology in the mouse. Male mice were housed singly in nest cages connected to either a circular tunnel, a recreational cage or a large box with food foraging apparatus. Spontaneous nocturnal out of nest activity or food foraging behavior in these environments was continuously monitored for a two week period during which time the effects of stress were examined. It was found that both repeated restraint and aggression stress markedly and persistently reduced out of nest nocturnal activity or food foraging behavior in all 3 environments but did not alter activity in a novel open field or plus maze or food or saccharin intake in the nest cage. In a preliminary experiment the reduction in out of nest activity by stress was attenuated by prior chronic treatment with the antidepressant, desmethylimipramine. Plasma corticosterone was elevated immediately after aggression stress but reduced 5 hr after chronic aggression stress. The reduction in activity did not appear the result of increased anxiety as measured by spontaneous risk assessment behavior in the nest. It is concluded that the decrease in out of nest activity after stress in the present studies models a withdrawn behavioral state and may be due to either or both a decrease in appetitive motivation to leave the nest or an increased aversion to the external environment which does not apparently involve anxiety.