Stress In Later Life Research Articles

Influence of Late Life Stressors on the Decisions of Older Women to Relocate into Congregate Senior Housing

Late-life stressors often require individuals to make substantial alterations in behavior and lifestyle and can affect their overall health and well-being. Relocation is a significant life stress, regardless of age. The primary aim of this study is to elucidate the push-pull factors associated with moving into congregate senior housing. The secondary aim is to investigate the decision-making processes and stresses associated with moving into a congregate living environment. Interviews were conducted with 26 women who were new residents in congregate senior housing. Relocation, as expected, was considered to be stressful, although individual differences were found among perceptions of relocation stresses. Women who had made the decision to relocate on their own showed evidence of better psychosocial well-being at the time of the move. One-quarter of the sample chose to move to provide care to another person. As the options for senior housing continue to evolve and the number of adults reaching advanced age continues to increase, it is important to understand the factors that contribute to successful adaptation. This knowledge will enable facility administrators to implement programs and procedures to assist incoming residents with acclimating to their new homes.

Perceived control as a longitudinal moderator of late-life stressors on depressive symptoms

Objectives: This study examined perceived control as a moderator of the relationship between late-life stressors and depressive symptoms among a sample of older New Zealanders. Method: Data were drawn from a longitudinal study with two data collection periods, one year apart. The Time 1 sample consisted of 1489 participants ranging in age from 65 to 94 years and 72% percent participated at Time 2. Correlational and multiple regression procedures were used to examine study hypotheses. Results: Results showed that Time 1 perceived control beliefs were a unique predictor of depressive symptoms at Time 2 after controlling for Time 1 depressives symptoms and other relevant variables. Further, perceived control beliefs at Time 1 moderated the relationship between late-life stressors and depressive symptoms at Time 2. Those with low perceived control demonstrated a stronger relationship between late-life stressors and depressive symptoms than those with high perceived control. Conclusion: This study provides evidence that perceived control influences levels of depressive symptoms over time among older adults. Results also support the hypothesis that control beliefs moderate the relationship between late-life stressors and depressive symptoms among older adults. Implications include attributional retraining to promote perceived control and subsequent well-being in older adults.

Selective Impact of Early Parental Responsivity on Adolescent Stress Reactivity

Research in animals has shown that early life experience, particularly parenting behaviors, influences later-life stress reactivity. Despite the tremendous relevance of this finding to human development and brain function, it has not been tested prospectively in humans. In this study two aspects of parenting were measured at age 4 in a sample of healthy, low socioeconomic status, African American children, and stress reactivity was measured in the same children 11–14 years later using a modified version of the Trier Social Stress Test (n = 55). Salivary cortisol was measured before, during and after the stressor and data were analyzed using piecewise hierarchical linear modeling. Parental responsivity, independent of the use of physical discipline, was positively related to cortisol reactivity. Effects were independent of subjective appraisals of the stressor and were also independent of other environmental risk factors and current psychosocial functioning. Therefore this study demonstrates in a novel and precise fashion that early childhood parental responsivity prospectively and independently predicts stress reactivity in adolescence.

Testing the cumulative stress and mismatch hypotheses of psychopathology in a rat model of early-life adversity

BackgroundIn the present study, we tested both the cumulative stress and the mismatch hypothesis of psychopathology. For this purpose the combined effects of early-life adversity and later-life stress exposure on behavioral markers of psychosis susceptibility were studied in male Wistar rats. MethodExperiment I: rat pups divided on the basis of the levels of their maternal care experience in low, medium or high maternal care groups, were reared post-weaning in groups (Exp. IA) or in social isolation (Exp. IB) and tested at adulthood under basal conditions or after an acute corticosterone (CORT) administration. Maternal care levels were assessed by measuring the dam's licking and grooming (LG) the first postnatal week of life.Experiment II: rat pups exposed as neonates to daily sessions of 8h of maternal separation (MS) on postnatal days 3, 4 and 5 either altogether in their home cage (HOME SEP) or alone in a novel environment (NOVEL SEP), were reared post-weaning in groups and tested at adulthood under basal conditions.Adult testing included behaviors marking psychosis susceptibility: apomorphine-induced gnawing (APO-gnawing), acoustic startle response and its modulation by a prepulse stimulus (PPI). The behavior of the Medium LG offspring was used as baseline reference for all the three experiments. ResultsExperiment I: Low maternal LG history alone had limited effects on the behavior of Wistar offspring, although increased acoustic startle and increased PPI, at high prepulse intensity levels, were observed. When low maternal LG history was combined with post-weaning social isolation, basal APO-gnawing was decreased and PPI increased, compared to High LG and Med LG offspring. This reflects attenuated psychosis susceptibility. High LG offspring reared in isolation displayed, however, the highest APO-gnawing and the lowest PPI levels among rats reared in social isolation, which is indicative for increased psychosis susceptibility. These findings support the mismatch hypothesis. For demonstration of the cumulative stress hypothesis an injection of CORT in the adult Low LG offspring was required that increased APO-gnawing and reduced PPI. This CORT-induced PPI disruption was greatly enhanced after additional isolation rearing. The High LG group, either socially housed or reared in isolation, was resistant to the acute effects of CORT at adulthood.Experiment II: MS increased psychosis susceptibility only in NOVEL SEP rats that had experienced MS in the context of early social isolation. These individuals displayed increased adult APO-gnawing and reduced PPI, if reared post-weaning in a condition that does not match with their early life social environment (i.e. group housing). This finding supports the mismatch hypothesis. ConclusionThe outcome of environmental manipulations on developmental programming of psychosis susceptibility depends on the interplay of early-life adversity and later-life stressors in a manner that supports the mismatch hypothesis. However, evidence for the cumulative stress hypothesis arises if vulnerable individuals are exposed in later life additionally to excess of the stress hormone CORT.

What contributes to perceived stress in later life? A recursive partitioning approach.

One possible explanation for the individual differences in outcomes of stress is the diversity of inputs that produce perceptions of being stressed. The current study examines how combinations of contextual features (e.g., social isolation, neighborhood quality, health problems, age discrimination, financial concerns, and recent life events) of later life contribute to overall feelings of stress. Recursive partitioning techniques (regression trees and random forests) were used to examine unique interrelations between predictors of perceived stress in a sample of 282 community-dwelling adults. Trees provided possible examples of equifinality (i.e., subsets of people with similar levels of perceived stress but different predictors) as well as identification both of contextual combinations that separated participants with very high and very low perceived stress. Random forest analyses aggregated across many trees based on permuted versions of the data and predictors; loneliness, financial strain, neighborhood strain, ageism, and to some extent life events emerged as important predictors. Interviews with a subsample of participants provided both thick description of the complex relationships identified in the trees, as well as additional risks not appearing in the survey results. Together, the analyses highlight what may be missed when stress is used as a simple unidimensional construct and can guide differential intervention efforts.

Poor Vision, Functioning, and Depressive Symptoms: A Test of the Activity Restriction Model

This study tested the applicability of the activity restriction model of depressed affect to the context of poor vision in late life. This model hypothesizes that late-life stressors contribute to poorer mental health not only directly but also indirectly by restricting routine everyday functioning. We used data from a national probability-based sample of older adults (N = 1,178; M = 69.2 years, approximately 50% female). Vision was assessed both subjectively (via self-report) and objectively (via a visual acuity test). Respondents also reported on their levels of physical and driving limitations, feelings of social isolation, and symptoms of depression. Path analyses indicated a strong fit of the data to the activity restriction model for subjective vision. In addition to directly contributing to higher depressive symptomatology, subjective vision contributed to depressive symptoms indirectly by predicting more physical limitations and feelings of social isolation that, in turn, contributed to more symptoms of depression; driving limitations did not mediate the relationship between subjective vision and depressive symptomatology. Objective vision contributed significantly to physical and driving limitations but was unrelated to feelings of social isolation and depressive symptomatology. Supporting the activity restriction model, poorer self-rated vision in late life contributes to lower mental health directly and also indirectly by restricting individuals' ability to carry out routine day-to-day physical activities and increasing their feelings of social isolation. Interventions for older adults with vision-related problems could focus on maintaining or enhancing their physical and social functioning in order to promote their adaptation to poor vision.

Hypoxia in early life is associated with lasting changes in left ventricular structure and function at maturity in the rat

BackgroundThere is a growing population of adults with repaired cyanotic congenital heart disease. These patients have increased risk of impaired cardiac health and premature death. We hypothesized that hypoxia in early life before surgical intervention causes lasting changes in left ventricular structure and function with physiological implications in later life. MethodsSprague–Dawley rats reared initially hypoxic conditions (FiO2=0.12) for days 1–10 of life were compared to rats reared only in ambient air. Cellular morphology and viability were compared among LV cardiomyocytes and histological analyses were performed on LV myocardium and arterioles. Intracellular calcium transients and cell shortening were measured in freshly-isolated cardiomyocytes, and mitochondrial hexokinase 2 (HK2) expression and activity were determined. Transthoracic echocardiography was used to assess LV function in anesthetized animals. ResultsCardiomyocytes from adult animals following hypoxia in early life had greater cellular volumes but significantly reduced viability. Echocardiographic analyses revealed LV hypertrophy and diastolic dysfunction, and alterations in cardiomyocyte calcium transients and cell shortening suggested impaired diastolic calcium reuptake. Histological analyses revealed significantly greater intima–media thickness and decreased lumen area in LV arterioles from hypoxic animals. Alterations in mitochondrial HK2 protein distribution and activity were also observed which may contribute to cardiomyocyte fragility. ConclusionsHypoxia in early life causes lasting changes in left ventricular structure and function that may negatively influence myocardial and vascular responses to physiological stress in later life. These data have implications for the growing population of adults with repaired or palliated cyanotic congenital heart disease.

The prenatal origins of lung cancer. I. The fetus

People differ in their susceptibility to developing cancer on exposure to carcinogens such as tobacco. What causes this is largely unknown. One possibility is that it is determined by nutritional influences during development that permanently change the structure and function of the baby's body. We studied an older and a younger cohort, totaling 20,431 men and women, born in Helsinki during 1924-1933 and 1934-1944. Their body size at birth had been recorded. Of them, 385 had developed lung cancer. Smoking history was known for 6,822 people. At birth, babies who later developed lung cancer had a high ponderal index (birthweight/length(3)). This association was confined to people whose mother's height was below the median. Among these people in the older cohort, the hazard ratio associated with a ponderal index >30 kg/m(3) was 3.1 (95% CI 1.6-5.9), in comparison to those with a ponderal index of 26 kg/m(3) or less (P for trend < 0.001). The equivalent figures for the younger cohort were 2.9 (1.2-7.0, P for trend = 0.001) and this association was independent of smoking. We suggest that a high ponderal index in babies born to short mothers is the result of low amino acid delivery to the fetus in relation to glucose delivery. We hypothesize that this impairs the development of the babies' antioxidant systems and makes them vulnerable to oxidative stress in later life. This is the first evidence that fetal programming may determine vulnerability to carcinogens in humans.

The geriatric population and psychiatric medication.

With improvement in medical services in the last few years, there has been a constant rise in the geriatric population throughout the world, more so in the developing countries. The elderly are highly prone to develop psychiatric disorders, probably because of age related changes in the brain, concomitant physical disorders, as well as increased stress in later life. Psychiatric disorders in this population may have a different presentation than in other groups and some of psychopathologies might be mistaken for normal age related changes by an unwary clinician. Therefore the need of the day is to train psychiatrists and physicians to better recognize and manage mental disorders in this age group.

Impairment of developmental stem cell-mediated striatal neurogenesis and pluripotency genes in a knock-in model of Huntington's disease

The pathogenesis of Huntington's disease (HD) remains elusive. The identification of increasingly early pathophysiological abnormalities in HD suggests the possibility that impairments of striatal medium spiny neuron (MSN) specification and maturation may underlie the etiology of HD. In fact, we demonstrate that HD knock-in (Hdh-Q111) mice exhibited delayed acquisition of early striatal cytoarchitecture with aberrant expression of progressive markers of MSN neurogenesis (Islet1, DARPP-32, mGluR1, and NeuN). Hdh-Q111 striatal progenitors also displayed delayed cell cycle exit between E13.5-15.5 (BrdU birth-dating) and an enhanced fraction of abnormal cycling cells in association with expansion of the pool of intermediate progenitors and over expression of the core pluripotency (PP) factor, Sox2. Clonal analysis further revealed that Hdh-Q111 neural stem cells (NSCs) displayed: impaired lineage restriction, reduced proliferative potential, enhanced late-stage self-renewal, and deregulated MSN subtype specification. Further, our analysis revealed that in addition to Sox2, the core PP factor, Nanog is expressed within the striatal generative and mantle regions, and in Hdh-Q111 embryos the fraction of Nanog-expressing MSN precursors was substantially increased. Moreover, compared to Hdh-Q18 embryos, the Hdh-Q111 striatal anlagen exhibited significantly higher levels of the essential PP cofactor, Stat3. These findings suggest that Sox2 and Nanog may play roles during a selective window of embryonic brain maturation, and alterations of these factors may, in part, be responsible for mediating the aberrant program of Hdh-Q111 striatal MSN specification and maturation. We propose that these HD-associated developmental abnormalities might compromise neuronal homeostasis and subsequently render MSNs more vulnerable to late life stressors.

Effect of early life thermal conditioning and immune challenge on thermotolerance and humoral immune competence in adult laying hens

Effects of early life experience with climatic (heat) and hygienic [lipopolysaccharide (LPS)] stress on adaptability to the same stressors in later life were studied in laying hens. Chicks were exposed to 37 degrees C for 24 h at d 5 of age (n = 12) or were i.v.-administered once with 1 mg/kg of BW of LPS at 6 wk of age (n = 12), whereas a control group was reared under standard conditions receiving a placebo treatment of PBS (n = 36). At 24 wk of age, hens treated in early life were reexposed to the same stressor. Early life control hens were exposed to heat stress (n = 12), i.v.-administered with LPS (n = 12), or not exposed (n = 12). To evaluate improvement of adaptability, effects of climatic and hygienic stress on performance, humoral immune competence, and endocrine responsiveness were investigated in hens with early life experience to the stressors and hens only exposed to the stressors in later life. Early life heat exposure did not affect performance, immune, and endocrine parameters. Treatment x time interactions were found for level of antibody (Ab) binding to LPS and keyhole limpet hemocyanin (KLH) after LPS administration, indicating that hens with early life LPS experience differed in response level (Ab binding to LPS) and response pattern (Ab binding to LPS and KLH) compared with hens administered with LPS only at adult age. Our data suggest that early life heat stress exposure did not affect adaptability of laying hens to heat stress in later life. However, early life LPS exposure affected kinetics and magnitude of Ab levels binding to LPS and KLH, indicating that early life LPS exposure can enhance the status of immune reactivity or induce a higher sensitivity to LPS.

Personality predicts recurrence of late-life depression

ObjectiveTo examine the association of personality with recurrence of depression in later life. MethodA subsample of 91 subjects from the Longitudinal Aging Study Amsterdam (LASA; baseline sample size n=3107; aged ≥55 years) depressed at baseline, who had recovered in the course of three years (first follow-up cycle) was identified. 41 (45%) respondents experienced a recurrence during the subsequent six years. The influences of personality and late life stress (demographic factors, health and social factors) on recurrence were investigated prospectively. ResultsRecurrence of depression was associated with a high level of neuroticism and low level of mastery, residual depressive symptoms at time of recovery, female gender, pain complaints and feelings of loneliness. In multivariable analysis entering all predictors significant in single variable analysis, residual depressive symptoms and lack of mastery remained significantly associated with recurrence. ConclusionIn predicting the recurrence of depression in later life, the direct effects of personality remain important and comparable in strength with other late life stressors related to recurrence.

Twin-to-twin transfusion syndrome: current understanding of pathophysiology, in-utero therapy and impact for future development

Whereas monochorionic twins account for only 30% of twin gestations, they contribute to a disproportionate extent to the overall twin perinatal morbidity and mortality. Twin-to-twin transfusion syndrome can occur at any point in a monochorionic gestation but is associated with significant increases in both morbidity and mortality when it develops before 26 weeks of gestation. It is still not possible to predict accurately those pregnancies that will be affected. This has resulted in the practice of routine ultrasound surveillance beginning at the end of the first trimester. Our understanding of the physiology still has many gaps but there is an increased recognition of the heterogeneity that exists especially in the early stages of the disease. The role of the cardiovascular response of the recipient twin offers the potential for further refining the application of our current treatment modalities and may offer insight into future therapies. The optimal therapy at this point in time resides clearly with selective laser photocoagulation, and further refinements of techniques and patient selection may continue to improve outcomes. Finally, the in-utero responses generated by the fetuses to the physiologic stress of twin-to-twin transfusion may influence their response or ability to respond to cardiovascular stress in later life. If there is in-utero programming, then the detection and timely treatment of conditions such as twin-twin transfusion syndrome may have lifelong implications for both members of the twin pair.

Intrauterine Programmierung von Störungen der Hirnfunktion im späteren Leben

Die Entwicklung der Hirnfunktion wird pränatal durch epigenetische Faktoren, die insbesondere mit einer fetalen Mangelversorgung oder erhöhten fetalen Stresshormonkonzentrationen einhergehen, beeinflusst. Schon eine moderate Mangelernährung hat Effekte auf die Hirnentwicklung u.a. über eine Hemmung des Systems des insulinähnlichen Wachstumsfaktors. Daneben führt sie zu einer Erhöhung von mütterlichen Kortisolkonzentrationen im fetalen Kreislauf. Erhöhte fetale Kortisolkonzentrationen, sei es aufgrund fetaler Mangelversorgung, Stress oder pränataler Gabe von Glukokortikoiden, führen ebenfalls zu Störungen der Hirnentwicklung. Darüber hinaus induzieren sie in den letzten Wochen der Schwangerschaft, wenn die kindliche Hypophysen-Hypothalamus-Nebennieren-(HHN)-Achse reift, eine dauerhafte Desensitivierung von Glukokortikoidrezeptoren im Hippokampus. Diese bewirkt eine verminderte negative Rückkopplung der HHN-Achse mit der Folge einer verstärkten Kortisolausschüttung und einer erhöhten Stressempfindlichkeit im späteren Leben. Die Störungen der Hirnentwicklung und die dauerhaft erhöhten Kortisolspiegel induzieren subtile kognitive Störungen, Verhaltensauffälligkeiten und eine Prädisposition für depressive und schizophrene Erkrankungen.

Early weaning results in less active behaviour, accompanied by lower 5-HT 1A and higher 5-HT 2A receptor mRNA expression in specific brain regions of female pigs

In rodents and humans stressful events in early life e.g. maternal deprivation, can increase sensitivity to stress in later life. Humans may become more susceptible to mood disorders, e.g. depression. In livestock species, such as pigs, early weaning is a form of maternal deprivation. We investigated behavioural consequences in 99 female pigs weaned at three different ages (12, 21 and 42 days; d12, d21, d42). Pigs were habituated to an open field arena over 6 days before being given 5-min open-field tests over three subsequent days (days 77-79). Early-weaned pigs (d12) showed behavioural inhibition (reduced vocalisations and lower activity) compared with later-weaned pigs, although in all groups these measures declined over the three tests, so this treatment difference might reflect more rapid habituation to the test in d12 pigs. Long-term effects on mood-related 5-HT receptor subtypes were measured in the brain at 90 days in a random sample of the d12 (n=8) and d42 pigs (n=8), using (3)H-ligand-binding and autoradiography and in situ hybridisation histochemistry. There were no differences between weaning ages in binding of (3)H-8-OH-DPAT (5-HT(1A) receptor agonist) or of (3)H-ketanserin (5-HT(2A) receptor antagonist) to any brain region studied. In d12 pigs, 5-HT(1A) receptor mRNA expression per unit area was 29%, 63%, 52% and 64% lower than in d42 pigs in the parvocellular PVN, amygdala and hippocampal dentate gyrus and pyramidal cell layer, respectively. The ratio of expression per cell to expressing cells per unit area was also lower, by 31%, in the pars horizontalis of the PVN in d12 pigs. Conversely, 5-HT(2A) receptor mRNA was expressed at a 25% and 28% higher density per unit area in the amygdala and pyramidal cell layer of the hippocampus, respectively, in these d12 pigs. In individual pigs, across brain regions, 5-HT(1A) receptor mRNA data were 70-79% correlated with binding data but no correlation was found for 5-HT(2A) data, suggesting different regulatory mechanisms. The behavioural and neurobiological responses to early weaning might represent either dysfunction or adaptation. Further investigation is required.

Conversation with Rudolf Moos

Conversation with Rudolf Moos

Modelling prenatal bacterial infection: Functional consequences of altered hypothalamic pituitary adrenal axis development

Prenatal exposure of animals to bacterial endotoxin is an experimental model of systemic maternal infection in the human pregnancy. Previous studies in the rat have demonstrated that such exposure is associated with long term alterations to hypothalamic pituitary adrenal (HPA) axis development. Typically, these animals display an elevated HPA response to stress in adulthood. As neural development is more similar in the human and the guinea pig than the rat, this study adopted a guinea pig model of pregnancy to explore the effects of endotoxin exposure on the HPA axis in the offspring. The offspring of dams exposed to endotoxin exhibited an attenuated cortisol response to the novel environment stress in the weaning period. The degree to which this cortisol response was both buffered by the mother's presence, and habituated to on repeated exposure, differed significantly between the prenatal treatment groups. In adulthood, a diminished cortisol response to the immune challenge was only evident in the female offspring, while both male and female offspring exhibited altered febrile responses. The results of the present study indicate that prenatal bacterial exposure in the guinea pig results in offspring with lower cortisol responses to stress in later life. These findings contrast past research that has used the rat to model pregnancy. As such, the use of the guinea pig to model infection may provide a useful alternative model of human pregnancy to explore programming effects.

Psychological resilience, positive emotions, and successful adaptation to stress in later life.

In 3 studies, the authors investigated the functional role of psychological resilience and positive emotions in the stress process. Studies 1a and 1b explored naturally occurring daily stressors. Study 2 examined data from a sample of recently bereaved widows. Across studies, multilevel random coefficient modeling analyses revealed that the occurrence of daily positive emotions serves to moderate stress reactivity and mediate stress recovery. Findings also indicated that differences in psychological resilience accounted for meaningful variation in daily emotional responses to stress. Higher levels of trait resilience predicted a weaker association between positive and negative emotions, particularly on days characterized by heightened stress. Finally, findings indicated that over time, the experience of positive emotions functions to assist high-resilient individuals in their ability to recover effectively from daily stress. Implications for research into protective factors that serve to inhibit the scope, severity, and diffusion of daily stressors in later adulthood are discussed.

Long-term patterns and predictors of successful stressor resolution in later life.

At 1 year, 4 years, and 10 years after baseline, late-middle-aged adults reported whether they had successfully resolved their most important stressor of the past year. Compared to individuals who never resolved focal stressors over the 10-year interval, those who always did consistently showed less negative stressor appraisal, less reliance on avoidance coping, and less use of exploratory relative to directed coping responses, independent of type and severity of focal stressor. Less use of exploratory relative to directed coping and having more social resources, fewer health problems, and fewer depressive symptoms at baseline predicted more stressor resolution over the next 10 years. These predictors are promising foci for prospective efforts to optimize ways in which aging adults manage late-life stressors.

Stress, age, and immune function: toward a lifespan approach.

Both aging processes and psychological stress affect the immune system: Each can dysregulate immune function with a potentially substantial impact on physical health. Worse, the effects of stress and age are interactive. Psychological stress can both mimic and exacerbate the effects of aging, with older adults often showing greater immunological impairment to stress than younger adults. In addition, stressful experiences very early in life can alter the responsiveness of the nervous system and immune system. We review the unique impact of aging and stress on immune function, followed by evidence of interactions between age and stress. Further, we suggest that prenatal or early life stress may increase the likelihood of maladaptive immune responses to stress in late life. An understanding of the interactive effects of stress and age is critical to efforts to determine underlying mechanisms, clarify the directionality of effects, and develop effective interventions in early and late life.