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ABSTRACT: Being overweight or obese is associated with reduced white matter integrity throughout the brain. It is not yet clear which physiological systems mediate the association between inter-individual variation in adiposity and white matter. We tested whether composite indicators of cardiovascular, lipid, glucose, and inflammatory factors would mediate the adiposity-related variation in white matter microstructure, measured with diffusion tensor imaging on a group of neurologically healthy adults (N=155). A composite factor representing adiposity (comprised of body mass index and waist circumference) was negatively associated fractional anisotropy, and increased radial diffusivity, throughout the brain, a pattern linked to myelin structure changes in non-human animal models. A similar global negative association was found for factors representing inflammation and, to a lesser extent, glucose regulation. In contrast, factors for blood pressure and dyslipidemia had positive associations with white matter in isolated brain regions. Taken together, these competing influences on the diffusion signal were significant mediators linking adiposity to white matter and explained up to fifty-percent of the adiposity-white matter variance. These results provide the first evidence for contrasting physiological pathways, a globally distributed immunity-linked negative component and a more localized vascular-linked positive component, that associate adiposity to individual differences in the microstructure of white matter tracts in otherwise healthy adults.
NeuroImage 04/2013; · 5.89 Impact Factor
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ABSTRACT: BACKGROUND: Prolonged, intensive treatment regimens often disrupt families of children with cancer. Siblings are at increased risk for distress, but factors underlying this risk have received limited empirical attention. In this study, the authors examined associations between the family context and sibling distress. METHODS: Siblings of children with cancer (ages 8-18 years; N = 209) and parents (186 mothers and 70 fathers) completed measures of sibling distress, family functioning, parenting, and parent post-traumatic stress. Associations between sibling distress and each family risk factor were evaluated. Then, family risks were considered simultaneously by calculating cumulative family risk index scores. RESULTS: After controlling for sociodemographic covariates, greater sibling distress was associated with more sibling-reported problems with family functioning and parental psychological control, lower sibling-reported maternal acceptance, and lower paternal self-reported acceptance. When risk factors were considered together, the results supported a quadratic model in which associations between family risk and sibling distress were stronger at higher levels of risk. CONCLUSIONS: The current findings support a contextual model of sibling adjustment to childhood cancer in which elevated distress is predicted by family risk factors, both alone and in combination. Cancer 2013;000:000-000. © 2013 American Cancer Society.
Cancer 04/2013; · 4.77 Impact Factor
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ABSTRACT: OBJECTIVES: (1) To examine the acceptability and feasibility of a stress management intervention for caregivers of children recently diagnosed with cancer. (2) To explore whether caregivers with lower baseline perceived social support derive greater benefit from the intervention than those with higher perceived support. METHODS: 45 primary caregivers were randomly assigned to intervention or standard care. Of these, 37 completed measures of social support, depression, anxiety, and perceived stress at both pre-intervention (T1; mean = 24 days post-diagnosis) and post-intervention time points (T2; mean = 165 days post-diagnosis). RESULTS: Enrollment, retention, and satisfaction data support feasibility and acceptability of the intervention. There was no overall significant impact of participation in the intervention on levels of distress at T2. However, T1 social support moderated intervention response, with caregivers who perceived lower T1 support showing greater psychological benefit from the intervention. CONCLUSIONS: Primary caregivers with lower levels of perceived social support may benefit from preemptive stress management intervention.
Journal of Pediatric Psychology 01/2013; · 2.91 Impact Factor
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ABSTRACT: Introduction. Research focusing on the long-term sequelae of diagnosis and treatment for childhood cancer suggests that although the majority of survivors are not at increased risk for psychopathology, many experience persistent problems in other domains that greatly affect quality of life (QoL). One such domain is social functioning. To date, little is known about the impact of childhood cancer on social functioning and related QoL during emerging adulthood, the developmental period that spans the late teens and early twenties and is characterized, in part, by explorations in love and romantic relationships. Aim. To document emerging adult survivors' perceptions of their romantic relationships through a descriptive qualitative study. Main Outcome Measures. Recurrent themes from interviews were extracted via qualitative content-based analysis. Methods. Eighteen female survivors of childhood cancer, ages 18-25, participated in a phone interview focused on past and present romantic partnerships. Results. Themes from coded transcripts included redefined life priorities and perspective, concerns with disclosure of cancer history and emotions, negative body image as a result of illness and treatment side effects, and worries about fertility and health of future children. Survivors related these concerns to their histories of childhood cancer and discussed the impact on the development and maintenance of romantic relationships. Conclusions. Overall, survivors reported a number of relationship concerns that have the potential to interfere with their ability to move toward emotional and physical intimacy in relationships, a key task of emerging adulthood. These findings suggest a number of testable hypotheses for future research, have the potential to inform the construction of new measures that more accurately evaluate social functioning of childhood cancer survivors, and emphasize the importance of ongoing assessment by health care providers of developmentally salient issues like love/romance. Thompson AL, Long KA, and Marsland AL. Impact of childhood cancer on emerging adult survivors' romantic relationships: A qualitative account. J Sex Med **;**:**-**.
Journal of Sexual Medicine 10/2012; · 3.55 Impact Factor
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ABSTRACT: Each year, 14,000 children are diagnosed with cancer in the United States. Prolonged, intensive treatment regimens disrupt the entire family system, but effects on siblings are poorly understood. In this preliminary investigation, we employed a risk and resistance framework to study adjustment among 30 siblings (aged 10-17) of children undergoing cancer treatment. We examined whether or not objective stress associated with the cancer experience (contextual threat) predicted sibling distress and explored demographic and disease-related predictors of sibling adjustment. Contextual threat was positively associated with sibling-reported distress, independent of sibling age, gender, birth order relative to the child with cancer, and cancer treatment intensity. From among the demographic and disease-related factors, only younger birth order relative to the child with cancer was independently associated with sibling distress. These results suggest that a subset of siblings may be at increased risk for elevated distress in the face of their brother's or sister's illness.
Journal of Clinical Psychology in Medical Settings 09/2012; · 1.49 Impact Factor
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ABSTRACT: Socioeconomic disadvantage confers risk for aspects of ill health that may be mediated by systemic inflammatory influences on the integrity of distributed brain networks. Following this hypothesis, we tested whether socioeconomic disadvantage related to the structural integrity of white matter tracts connecting brain regions of distributed networks, and whether such a relationship would be mediated by anthropometric, behavioral, and molecular risk factors associated with systemic inflammation. Otherwise healthy adults (N= 155, aged 30-50 years, 78 men) completed protocols assessing multilevel indicators of socioeconomic position (SEP), anthropometric and behavioral measures of adiposity and cigarette smoking, circulating levels of C-reactive protein (CRP), and white matter integrity by diffusion tensor imaging. Mediation modeling was used to test associations between SEP indicators and measures of white matter tract integrity, as well as indirect mediating paths. Measures of tract integrity followed a socioeconomic gradient: individuals completing more schooling, earning higher incomes, and residing in advantaged neighborhoods exhibited increases in white matter fractional anisotropy and decreases in radial diffusivity, relative to disadvantaged individuals. Moreover, analysis of indirect paths showed that adiposity, cigarette smoking, and CRP partially mediated these effects. Socioeconomic inequalities may relate to diverse health disparities via inflammatory pathways impacting the structural integrity of brain networks.
Cerebral Cortex 07/2012; · 6.54 Impact Factor
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ABSTRACT: Maintaining brain health promotes successful aging. The main determinants of brain health are the preservation of cognitive function and remaining free from structural and metabolic abnormalities, including loss of neuronal synapses, atrophy, small vessel disease and focal amyloid deposits visible by neuroimaging. Promising studies indicate that these determinants are to some extent modifiable, even among adults seventy years and older. Converging animal and human evidence further suggests that inflammation is a shared mechanism, contributing to both cognitive decline and abnormalities in brain structure and metabolism. Thus, inflammation may provide a target for intervention. Specifically, circulating inflammatory markers have been associated with declines in cognitive function and worsening of brain structural and metabolic characteristics. Additionally, it has been proposed that older brains are characterized by a sensitization to neuroinflammatory responses, even in the absence of overt disease. This increased propensity to central inflammation may contribute to poor brain health and premature brain aging. Still unknown is whether and how peripheral inflammatory factors directly contribute to decline of brain health. Human research is limited by the challenges of directly measuring neuroinflammation in vivo. This review assesses the role that inflammation may play in the brain changes that often accompany aging, focusing on relationships between peripheral inflammatory markers and brain health among well-functioning, community-dwelling adults seventy years and older. We propose that monitoring and maintaining lower levels of systemic and central inflammation among older adults could help preserve brain health and support successful aging. Hence, we also identify plausible ways and novel experimental study designs of maintaining brain health late in age through interventions that target the immune system.
Aging and disease. 02/2012; 3(1):16-33.
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ABSTRACT: Experimental evidence links poor sleep with susceptibility to infectious illness; however, it remains to be determined if naturally occurring sleep is associated with immune responses known to play a role in protection against infection. The aim of this study was to determine whether sleep duration, sleep efficiency, and sleep quality, assessed in the natural environment, predict magnitude of antibody responses to a novel antigen among community volunteers in midlife.
Observational.
Healthy midlife adults (n = 125; 70 female; age 40-60 yr) received the standard 3-dose hepatitis B vaccination series. Actigraphy and electronic sleep diaries were used to assess sleep duration, sleep efficiency, and subjective sleep quality. Viral-specific antibody titers were obtained prior to the 2nd and 3rd vaccination to assess primary and secondary antibody responses. Clinical protection status (anti-hepatitis B surface antigen immunoglobulin G ≥ 10 mIU/ml) was assessed 6 mo after the final immunization. Regression analyses revealed that shorter actigraphy-based sleep duration was associated with a lower secondary antibody response independent of age, sex, body mass index, and response to the initial immunization. Shorter sleep duration, measured by actigraphy and sleep diary, also predicted a decreased likelihood of being clinically protected from hepatitis B at the conclusion of the vaccination series. Neither sleep efficiency nor subjective sleep quality were significant predictors of antibody response.
Short sleep duration in the natural environment may negatively affect in vivo antibody responses to novel antigens, providing a possible explanation for observed associations of poor sleep with increased susceptibility to infectious disease. CITATION: Prather AA; Hall M; Fury JM; Ross DC; Muldoon MF; Cohen S; Marsland AL. Sleep and antibody response to hepatitis B vaccination. SLEEP 2012;35(8):1063-1069.
Sleep 01/2012; 35(8):1063-9. · 5.05 Impact Factor
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ABSTRACT: Allostatic load is a commonly used metric of health risk based on the hypothesis that recurrent exposure to environmental demands (e.g., stress) engenders a progressive dysregulation of multiple physiological systems. Prominent indicators of response to environmental challenges, such as stress-related hormones, sympatho-vagal balance, or inflammatory cytokines, comprise primary allostatic mediators. Secondary mediators reflect ensuing biological alterations that accumulate over time and confer risk for clinical disease but overlap substantially with a second metric of health risk, the metabolic syndrome. Whether allostatic load mediators covary and thus warrant treatment as a unitary construct remains to be established and, in particular, the relation of allostatic load parameters to the metabolic syndrome requires elucidation. Here, we employ confirmatory factor analysis to test: 1) whether a single common factor underlies variation in physiological systems associated with allostatic load; and 2) whether allostatic load parameters continue to load on a single common factor if a second factor representing the metabolic syndrome is also modeled. Participants were 645 adults from Allegheny County, PA (30-54 years old, 82% non-Hispanic white, 52% female) who were free of confounding medications. Model fitting supported a single, second-order factor underlying variance in the allostatic load components available in this study (metabolic, inflammatory and vagal measures). Further, this common factor reflecting covariation among allostatic load components persisted when a latent factor representing metabolic syndrome facets was conjointly modeled. Overall, this study provides novel evidence that the modeled allostatic load components do share common variance as hypothesized. Moreover, the common variance suggests the existence of statistical coherence above and beyond that attributable to the metabolic syndrome.
PLoS ONE 01/2012; 7(10):e47246. · 4.09 Impact Factor
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ABSTRACT: Psychological stress and sleep disturbances are highly prevalent and are both implicated in the etiology of cardiovascular diseases. Given the common co-occurrence of psychological distress and sleep disturbances including short sleep duration, this study examined the combined effects of these two factors on blood pressure reactivity to immediate mental challenge tasks after well-rested and sleep-deprived experimental conditions.
Participants (n = 20) were healthy young adults free from current or past sleep, psychiatric, or major medical disorders. Using a within-subjects crossover design, we examined acute stress reactivity under two experimental conditions: after a night of normal sleep in the laboratory and after a night of total sleep deprivation. Two standardized psychological stress tasks were administered, a Stroop color-word naming interference task and a speech task, which were preceded by a prestress baseline period and followed by a poststress recovery period. Each period was 10 minutes in duration, and blood pressure recordings were collected every 2.5 minutes throughout each period. Mean blood pressure responses during stress and recovery periods were examined with a mixed-effects analysis of covariance, controlling for baseline blood pressure.
There was a significant interaction between sleep deprivation and stress on systolic blood pressure (F(2,82.7) = 4.05, p = .02). Systolic blood pressure was higher in the sleep deprivation condition compared with the normal sleep condition during the speech task and during the two baseline periods.
Sleep deprivation amplified systolic blood pressure increases to psychological stress. Sleep loss may increase cardiovascular risk by dysregulating stress physiology.
Psychosomatic Medicine 09/2011; 73(8):679-82. · 3.97 Impact Factor
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ABSTRACT: It is proposed that socioeconomic conditions in early childhood effect immune programming, with poorer conditions resulting in adult phenotypes that are prone to inflammation. Recent evidence supports this possibility, showing an inverse association of childhood SES with adult markers of systemic inflammation. In this study, we further investigate this association, extending prior studies to include an examination of multiple indices of SES across distinct periods of childhood. Subjects were 112 men and women, 40-60 years of age (88.6% Caucasian). Childhood SES was indexed by a composite of three indicators of parental wealth (parental home and vehicle ownership, and number of bedrooms per child in the family home) averaged across 2 year periods of childhood between 1 and 18 years old. Higher adult serum concentrations of interleukin (IL)-6 were associated with lower SES in early childhood (years 1-2) (β=-.05, p<.05), associations that were independent of adult age, personal income, educational attainment, gender, race, body mass index, and physical activity. These associations support recent suggestions that the early environment may program immune phenotypes that contribute to disease risk.
Brain Behavior and Immunity 06/2011; 25(7):1468-74. · 4.72 Impact Factor
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Kristin A Long,
Linda J Ewing,
Sheldon Cohen,
David Skoner,
Deborah Gentile,
Jennifer Koehrsen,
Chelsea Howe,
Amanda L Thompson,
Rhonda K Rosen,
Megan Ganley, Anna L Marsland
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ABSTRACT: Evidence supports a bidirectional relationship between stress and asthma exacerbations in children, suggesting that interventions to reduce stress may improve both psychosocial quality of life and disease course. Here, we examine the feasibility of a stress management intervention for 7- to 12-year-olds with asthma.
Two trials were conducted. Cohort 1 (n = 11) was recruited from the community and attended intervention sessions at an urban university. Cohort 2 (n = 7) was school based and recruited from an African American charter school. Six individual intervention sessions focused on psychoeducation about asthma, stress, and emotions; problem-solving and coping skills training; and relaxation training paired with physiological feedback. Pre- and post-intervention stress, mood, and lung function data were collected. Satisfaction surveys were administered after intervention completion.
The intervention was rated as highly acceptable by participating families. Feasibility was much stronger for the school-based than the university-based recruitment mechanism. Initial efficacy data suggest that both cohorts showed pre- to post-intervention improvements in lung function, perceived stress, and depressed mood.
Findings provide evidence for the feasibility of offering asthma-related stress management training in a school setting. Initial findings offer support for future, large-scale efficacy studies.
Journal of Asthma 03/2011; 48(2):162-70. · 1.52 Impact Factor
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ABSTRACT: This systematic review integrates qualitative and quantitative research findings regarding family changes in the context of childhood cancer. Twenty-eight quantitative, 42 qualitative, and one mixed-method studies were reviewed. Included studies focused on family functioning, marital quality, and/or parenting in the context of pediatric cancer, were written in English, and were published between 1996 and 2009. Overall, qualitative findings show that families alter roles, responsibilities, and day-to-day functioning to accommodate the needs of children with cancer. Although some degree of family reorganization is normative, the extent and impact of these changes varies. Quantitative work shows that mean levels of family functioning (e.g., cohesion, flexibility) are similar between families facing cancer and normative or comparison samples. However, families follow different trajectories of improvement, decline, or stability in family closeness and marital quality. Parenting has received limited quantitative research attention, but qualitative work suggests that parents perceive deeper bonds with ill children and may spoil or overprotect them. Conclusions support future work examining the influence of family-level variables on the adjustment of individual family members.
Clinical Child and Family Psychology Review 01/2011; 14(1):57-88. · 3.13 Impact Factor
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ABSTRACT: The metabolic syndrome is conceptualized as a clustering of risk factors--including insulin resistance, dyslipidemia, central adiposity, and elevated blood pressure (BP)--that increase the risk for cardiovascular disease and type 2 diabetes mellitus. Recent evidence suggests that markers of systemic inflammation may be included in the definition of the syndrome and play some role in its pathogenesis. In this study, we use a statistical modeling technique, confirmatory factor analysis, to evaluate relationships of systemic inflammation, as measured by plasma concentrations of C-reactive protein and interleukin-6, with the component factors of the metabolic syndrome (insulin resistance, dyslipidemia, central adiposity, and elevated BP) and to examine whether inflammation is a potential common pathway linking established components to the full syndrome. Subjects were 645 community volunteers aged 30 to 54 years (48% male, 82% European American, 18% African American). Consistent with existing literature, structural equation modeling adjusting for age, sex, and race confirmed a higher-order common factor underlying the covariation of insulin resistance, dyslipidemia, adiposity, and BP. Inflammation was positively associated with this common factor, accounting for 54% of its variance and partially mediating statistical aggregation of the component factors comprising the metabolic syndrome. These results were particularly strong for adiposity, raising the possibility that inflammatory processes stimulated by intraabdominal adipose tissue contribute to the development of the metabolic syndrome. The inclusion of inflammatory markers in the clinical definition of metabolic syndrome seems warranted and may improve prognostic assessment of risk of type 2 diabetes mellitus and cardiovascular disease.
Metabolism: clinical and experimental 12/2010; 59(12):1801-8. · 2.59 Impact Factor
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ABSTRACT: Laboratory studies show that individuals differ appreciably in the magnitude of their inflammatory responses to acute psychological stress. These individual differences are poorly understood, yet may contribute to variation in stress-associated disease vulnerability. The present study examined the possibility that affective responses to acute stress contribute to these differences. For this purpose, 102 relatively-healthy community volunteers (mean age 50 years; 60% female; 91.2% white) performed an acute stress protocol and measures of affective state and serum levels of the proinflammatory cytokine, interleukin (IL)-6 were collected at the end of a 30-min resting baseline, a 5-min evaluative public speaking task, and a 30-min recovery period. Results of regression analyses, controlling for age, race, gender, menopausal status, and body mass index, revealed a positive association of task-related increases in anger and anxiety with increases in IL-6 (R² change = .08, p = .004; R² change = .08, p = .005, respectively). Further examination showed that these affective responses to the task were independent predictors of change in IL-6. Cardiovascular reactivity to the task did not explain the association. These results suggest that individuals who exhibit angry or anxious responses to acute challenge are more vulnerable to stress-related increases in markers of systemic inflammation, possibly rendering them more susceptible to inflammatory disease.
Brain Behavior and Immunity 09/2010; 25(2):232-8. · 4.72 Impact Factor
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ABSTRACT: Although not all findings are consistent, growing evidence suggests that individuals high in dispositional hostility are at elevated risk for cardiovascular disease and all-cause mortality; however, the mechanisms of these associations remain unclear. One possibility is that hostility is associated with oxidative stress. Here, we explore relationships between hostility and a measure of systemic oxidative stress among a mid-life sample.
In a community sample of 223 adults aged 30 to 54 years (86% white, 50% female), oxidative stress was measured as the 24-hour urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG). An abbreviated Cook Medley Hostility Scale was used to measure dimensions of hostility.
Regression analyses controlling for demographic characteristics and cardiovascular risk factors showed a positive relationship of 8-OHdG with total hostility (beta = 0.003, p = .03) and hostile affect (beta = 0.018, p < .001).
These findings provide evidence that dispositional hostility, and in particular, hostile affect, covary positively with systemic oxidative stress, raising the possibility that oxidative stress contributes to the pathogenicity of hostile attributes.
Psychosomatic Medicine 04/2010; 72(3):273-80. · 3.97 Impact Factor
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ABSTRACT: To promote a broader understanding of the psychosocial impact of childhood cancer on siblings, a systematic review was undertaken. Directions for future research are proposed and clinical strategies are suggested for addressing the needs of these children.
Searches of Medline, PsycINFO and CINAHL revealed 65 relevant qualitative, quantitative, or mixed methods' papers published between 1997 and 2008. These papers were rated for scientific merit and findings were extracted for summary.
Siblings of children with cancer do not experience elevated mean rates of psychiatric disorders, but a significant subset experiences post-traumatic stress symptoms, negative emotional reactions (e.g. shock, fear, worry, sadness, helplessness, anger, and guilt), and poor quality of life in emotional, family, and social domains. In general, distress is greater closer to time of diagnosis. School difficulties are also evident within 2 years of diagnosis. Qualitative studies reveal family-level themes such as loss of attention and status as well as positive outcomes including increased sibling maturity and empathy.
Research regarding siblings of children with cancer continues to be methodologically limited. The conclusions of qualitative and quantitative studies differ considerably. We propose a research agenda to propel this field forward including greater attention to alterations in normative development (as opposed to psychiatric conditions), development of more appropriate quantitative measures, examination of potential moderators of adaptation, and use of prospective longitudinal designs. Siblings of children with cancer are a psychosocially at-risk group and should be provided with appropriate supportive services.
Psycho-Oncology 10/2009; 19(8):789-805. · 3.34 Impact Factor
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ABSTRACT: Growing evidence suggests that socioeconomic attributes of both childhood and adulthood confer risk for cardiovascular morbidity and mortality. In this study, we examine the association of both parental and individual educational attainment with C-reactive protein (CRP), an inflammatory mediator relevant to cardiovascular pathophysiology, in a mid-life community sample. Subjects were 811 men and women (394 men/417 women; 87% European-American/13% African-American), 30-54 years of age. Plasma concentrations of CRP were determined from blood samples obtained at a single session following an overnight fast. Regression analyses adjusting for age and race showed both parental education and individual education to be associated inversely with CRP in women, but not men. The relationship of parental education with CRP in women persisted on multivariable adjustment for both lifestyle risk factors (smoking, alcohol consumption, sleep, exercise, body mass index) and individual SES. Independent of reported personal educational attainment, mid-life adult women whose parents achieved fewer years of educational attainment exhibit higher levels of circulating CRP than women with higher parental education. This association may help explain the increased risk of atherosclerotic cardiovascular morbidity and mortality conferred by low childhood socioeconomic status.
Brain Behavior and Immunity 08/2009; 23(5):677-83. · 4.72 Impact Factor
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ABSTRACT: In studies employing functional magnetic resonance imaging (fMRI), reactivity of the amygdala to threat-related sensory cues (viz., facial displays of negative emotion) has been found to correlate positively with interindividual variability in testosterone levels of women and young men and to increase on acute administration of exogenous testosterone. Many of the biological actions of testosterone are mediated by intracellular androgen receptors (ARs), which exert transcriptional control of androgen-dependent genes and are expressed in various regions of the brain, including the amygdala. Transactivation potential of the AR decreases (yielding relative androgen insensitivity) with expansion a polyglutamine stretch in the N-terminal domain of the AR protein, as encoded by a trinucleotide (CAG) repeat polymorphism in exon 1 of the X-chromosome AR gene. Here we examined whether amygdala reactivity to threat-related facial expressions (fear, anger) differs as a function of AR CAG length variation and endogenous (salivary) testosterone in a mid-life sample of 41 healthy men (mean age=45.6 years, range: 34-54 years; CAG repeats, range: 19-29). Testosterone correlated inversely with participant age (r=-0.39, p=0.012) and positively with number of CAG repeats (r=0.45, p=0.003). In partial correlations adjusted for testosterone level, reactivity in the ventral amygdala was lowest among men with largest number of CAG repeats. This inverse association was seen in both the right (r(p)=-0.34, p<0.05) and left (r(p)=-0.32, p<0.05) hemisphere. Activation of dorsal amygdala, correlated positively with individual differences in salivary testosterone, also in right (r=0.40, p<0.02) and left (r=0.32, p<0.05) hemisphere, but was not affected by number of CAG repeats. Hence, androgenic influences on threat-related reactivity in the ventral amygdala may be moderated partially by CAG length variation in the AR gene. Because individual differences in salivary testosterone also predicted dorsal amygdala reactivity and did so independently of CAG repeats, it is suggested that androgenic influences within this anatomically distinct region may be mediated, in part, by non-genomic or AR-independent mechanisms.
Psychoneuroendocrinology 06/2009; 35(1):94-104. · 5.81 Impact Factor
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ABSTRACT: Activation of innate inflammatory pathways, marked by increased production of pro-inflammatory cytokines, has been proposed as a potential mechanism linking poor sleep and inflammatory disease risk. In the present study, we examined associations of self-reported sleep quality and duration, and a calculated measure of sleep debt with the production of pro-inflammatory cytokines, interleukin (IL)-6, IL-1beta, and tumor necrosis factor (TNF)-alpha among a community sample of 156 healthy adults. Bivariate correlations revealed an inverse association between sleep quality and production of all the three pro-inflammatory cytokines that was retained for IL-1beta after controlling for demographic and health characteristics. Hierarchical linear regressions also revealed that higher sleep debt scores predicted greater production of IL-1beta and IL-6 after adjusting for covariates. Secondary analyses showed an interaction between sleep debt and body mass index (BMI) in the prediction IL-1beta, suggesting that the impact of sleep debt on cytokine production is greater among participants with lower BMI scores. Further exploration of this potential psychophysiological pathway linking sleep difficulty and inflammatory disease susceptibility is warranted.
Biological psychology 06/2009; 82(1):12-7. · 4.36 Impact Factor
