Inflammation | Schreier Lab

Low-Grade Inflammation and Ambulatory Cortisol in Adolescents: Interaction Between Interviewer-Rated Versus Self-Rated Acute Stress and Chronic Stress

Objective: To determine whether the association between self-rated or interviewer-rated recent acute stress exposures and low-grade inflammation and daily cortisol production in adolescents is moderated by chronic stress ratings. Methods: Acute and chronic stress exposures were assessed in 261 adolescents aged 13 to 16 years using a semistructured life stress interview. The negative impact of acute stressors was independently rated by both adolescents (self-rated) and interviewers (interviewer-rated). Markers of inflammation (interleukin (IL)-6, IL-1ra, C-reactive protein) were measured from peripheral blood samples obtained via antecubital venipuncture. Participants collected 4 saliva samples at home on each of 6 consecutive days for the analysis of diurnal salivary cortisol profiles. Results: There were no main effects of acute stressors (self- and interviewer-rated) and chronic family or peer stress on adolescent inflammation markers and cortisol (p values > .10). However, the interaction between interviewer-rated acute stress and chronic family stress was significantly associated with adolescent inflammation markers (IL-6, IL-1ra). Specifically, as chronic family stress increased, the association between acute stressor impact (interviewer-rated) and inflammation markers became more positive (IL-6 (B = .054, SE = .023, p = .022); IL-1ra (B = .030, SE = .014, p = .034)). Interactions between self-rated acute stress and chronic family stress were not associated with any biological measures (p values > .10). Interactions between acute stressor impact (both self- and interviewer-rated) and chronic peer stress were also not significantly associated with any biological measures (p values > .05). Conclusions: Among adolescents, interviewer-based ratings of acute stressor impact may allow for better prediction of health-relevant inflammation markers than adolescents’ own ratings.

CITATION: Schreier, H. M. C. & Chen, E. (2016). Low-Grade Inflammation and Ambulatory Cortisol in Adolescents: Interaction Between Interviewer-Rated Versus Self-Rated Acute Stress and Chronic Stress. Psychosomatic Medicine.

Family Influences / Inflammation / Publications — No Comments
27
Aug 16

Social role conflict predicts stimulated cytokine production among men, not women

Objective: To assess whether perceived role conflict is associated with stimulated pro-inflammatory cytokine production and glucocorticoid sensitivity, and whether these associations are moderated by sex. Methods: 153 healthy adults (aged 45.8±5.5years, 78% female) listed their 3 main social roles and indicated the amount of role conflict they perceived between each pair of social roles. Subsequently, participants underwent blood draws and leukocyte response to microbial challenge and glucocorticoid sensitivity were assessed by incubating whole blood with lipopolysaccharide (LPS) in the presence or absence of hydrocortisone. Stimulated levels of Interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor alpha (TNFα) were measured. Results: Multiple regression analyses controlling for sociodemographics revealed significant sex×role conflict interactions for LPS-stimulated production of IL-1β, IL-6, and TNFα (all interaction ps<0.05), and a marginal interaction on LPS-stimulated IL-8 production (interaction p<0.10). Greater perceived role conflict was associated with greater pro-inflammatory cytokine production in response to microbial stimulation only among men, not women. There also were significant sex×role conflict interactions with respect to glucocorticoid sensitivity for IL-1β, IL-6, and TNFα production (all interaction ps<0.05) and a marginal interaction for IL-8 (interaction p<0.10). Greater perceived role conflict was unrelated to glucocorticoid sensitivity among women, but associated with less sensitivity to glucocorticoid signaling among men. Conclusions: Perceived social role conflict, indicating greater perceived demand across multiple social roles, may take a greater toll on the regulation of inflammatory processes among men compared to women.

CITATION: Schreier, H. M. C, Hoffer, L. C. & Chen, E. (2016). Social role conflict predicts stimulated cytokine production among men, not women. Brain, Behavior, & Immunity.

Adolescents / Chronic Illnesses / Family Influences / Inflammation / Publications — No Comments
15
Sep 15

Chronic traffic-related air pollution and stress interact to predict biologic and clinical outcomes in asthma

Background: Previous research has documented effects of both physical and social environmental exposures on childhood asthma. However, few studies have considered how these two environments might interact to affect asthma. Objective: This study aimed to test interactions between chronic exposure to traffic-related air pollution and chronic family stress in predicting biologic and clinical outcomes in children with asthma. Method: Children with asthma (n = 73, 9-18 years of age) were interviewed about life stress, and asthma-relevant inflammatory markers [cytokine production, immunoglobulin E (IgE), eosinophil counts] were measured. Parents reported on children’s symptoms. Children completed daily diaries of symptoms and peak expiratory flow rate (PEFR) measures at baseline and 6 months later. Exposure to traffic-related air pollution was assessed using a land use regression model for nitrogen dioxide concentrations. Results: NO(2) by stress interactions were found for interleukin-5 (beta for interaction term = -0.31, p = 0.02), IgE (interaction beta = -0.29, p = 0.02), and eosinophil counts (interaction beta = -0.24, p = 0.04). These interactions showed that higher chronic stress was associated with heightened inflammatory profiles as pollution levels decreased. Longitudinally, NO(2) by stress interactions emerged for daily diary symptoms (interaction beta = -0.28, p = 0.02), parent-reported symptoms (interaction beta = -0.25, p = 0.07), and PEFR (interaction beta = 0.30, p = 0.03). These interactions indicated that higher chronic stress was associated with increases over time in symptoms and decreases over time in PEFR as pollution levels decreased. Conclusions: The physical and social environments interacted in predicting both biologic and clinical outcomes in children with asthma, suggesting that when pollution exposure is more modest, vulnerability to asthma exacerbations may be heightened in children with higher chronic stress.

CITATION: Chen, E., Schreier, H. M. C., Strunk, R. C., & Brauer, M. (2008). Chronic traffic-related air pollution and stress interact to predict biologic and clinical outcomes in asthma. Environmental Health Perspectives, 116(7), 970-975.

Adolescents / Chronic Illnesses / Family Influences / Inflammation / Publications — No Comments
15
Sep 15

Longitudinal relationships between family routines and biological profiles among youth with asthma

Objective: To investigate whether longitudinal trajectories of inflammatory markers of asthma can be predicted by levels of family routines in youth with asthma. Design: Family routines were assessed through parent questionnaires and peripheral blood samples obtained from youth every 6 months throughout the 18-month study period. Longitudinal relationships were evaluated using hierarchical linear modeling. Main Outcome Measures: Mitogen-stimulated production of cytokines implicated in asthma, specifically IL-4, IL-5, and IL-13. Results: Youth with more family routines in their home environment showed decreases in IL-13 (but not IL-4 or IL-5) over the course of the study period. In turn, within-person analyses indicated that at times when stimulated production of IL-13 was high, asthma symptoms were also high, pointing to the clinical relevance of changes in IL-13 over time. A variety of child and parent psychosocial as well as child behavioral characteristics could not explain these effects. However, medication use eliminated the relationship between family routines and stimulated production of IL-13. Conclusion: Our study suggests that family routines predict asthma outcomes at the biological level, possibly through influencing medication use. Considering daily family behaviors when treating asthma may help improve both biological and clinical profiles in youth with asthma.

CITATION: Schreier, H. M. C. & Chen, E. (2010). Longitudinal relationships between family routines and biological profiles among youth with asthma. Health Psychology, 29(1), 82-90.

Adolescents / Family Influences / Inflammation / Publications / Socioeconomic Status — 1 Comment
09
Sep 15

Family chaos and adolescent inflammatory profiles: the moderating role of socioeconomic status

Objective: To test whether family chaos influences adolescents’ inflammatory profiles and whether adolescents from low socio- economic status (SES) environments are at higher risk for experiencing adverse inflammatory profiles from living in chaotic family environments. Methods: A total of 244 families with an adolescent aged 13 to 16 years participated. Parents completed measures of family SES and family chaos. Both systemic inflammation and stimulated proinflammatory cytokine production in response to bacterial challenge were assessed in adolescents. Results: Our results suggest that SES moderates the detrimental effect of family chaos on systemic inflammation and interleukin-6 (B = -0.010, standard error [SE] = 0.004, p = .026), but not C-reactive protein (B = 0.009, SE = 0.006, p = .11), and on stimulated proinflammatory cytokine production (B = -0.098, SE = 0.044, p = .026) in adolescents, such that a chaotic family environment is positively associated with greater systemic inflammation and greater stimulated proinflammatory cytokine production in adolescents as family SES declines. Conclusions: These findings indicate that living in chaotic family environments places youth who may be vulnerable based on socioeconomic factors at a potentially higher risk for inflammation-related diseases. Key words: inflammation, family chaos, adolescents, socioeconomic status.

CITATION: Schreier, H. M. C., Roy, L. B., Frimer, L., & Chen, E. (2014). Family chaos and adolescent inflammatory profiles: the moderating role of socioeconomic status. Psychosomatic Medicine, 76(6), 460-467.

Adolescents / Inflammation / Intervention / Publications / Volunteering — No Comments
08
Sep 15

Effect of volunteering on cardiovascular risk in adolescents

Importance The idea that individuals who help others incur health benefits themselves suggests a novel approach to improving health while simultaneously promoting greater civic orientation in our society. The present study is the first experimental trial, to our knowledge, of whether regular volunteering can reduce cardiovascular risk factors in adolescents. Objective To test a novel intervention that assigned adolescents to volunteer with elementary school–aged children as a means of improving adolescents’ cardiovascular risk profiles. Design Randomized controlled trial, with measurements taken at baseline and 4 months later (postintervention). Setting Urban public high school in western Canada. Participants One hundred six 10th-grade high school students who were fluent in English and free of chronic illnesses. Intervention Weekly volunteering with elementary school–aged children for 2 months vs wait-list control group. Main Outcome Measures Cardiovascular risk markers of C-reactive protein level, interleukin 6 level, total cholesterol level, and body mass index. Results No statistically significant group differences were found at baseline. Postintervention, adolescents in the intervention group showed significantly lower interleukin 6 levels (log₁₀ mean difference, 0.13; 95% CI, 0.004 to 0.251), cholesterol levels (log₁₀ mean difference, 0.03; 95% CI, 0.003 to 0.059), and body mass index (mean difference, 0.39; 95% CI, 0.07 to 0.71) compared with adolescents in the control group. Effects for C-reactive protein level were marginal (log₁₀ mean difference, 0.13; 95% CI, −0.011 to 0.275). Preliminary analyses within the intervention group suggest that those who increased the most in empathy and altruistic behaviors, and who decreased the most in negative mood, also showed the greatest decreases in cardiovascular risk over time. Conclusions and Relevance Adolescents who volunteer to help others also benefit themselves, suggesting a novel way to improve health.

CITATION: Schreier, H. M. C., Schonert-Reichl, K. A., & Chen, E. (2013). Effect of volunteering on cardiovascular risk in adolescents. JAMA – Pediatrics, 167(4), 327-332.

Inflammation / Publications — No Comments
08
Sep 15

Stress and food allergy: mechanistic considerations

Recent years have seen a marked increase in food allergy prevalence among children, particularly in Western countries, that cannot be explained by genetic factors alone. This has resulted in an increased effort to identify environmental risk factors underlying food allergies and to understand how these factors may be modified through interventions. Food allergy is an immune-mediated adverse reaction to food. Consequently, considerations of candidate risk factors have begun to focus on environmental influences that perturb the healthy development of the emerging immune system during critical periods of development (eg, prenatally and during early childhood), particularly in the gut. Given that psychosocial stress is known to play an important role in other allergic and inflammatory diseases, such as asthma, its potential role in food allergy is a growing area of research. However, research to date has largely focused on animal studies. This review synthesizes relevant animal research and epidemiological data, providing proof of concept for moderating influences of psychological stress on food allergy outcomes in humans. Pathways that may underlie associations between psychosocial stress and the expression of food allergy are discussed.

CITATION: Schreier, H. M. C. & Wright, R. J. (2013). Stress and food allergy: mechanistic considerations. Annals of Allergy, Asthma, & Immunology, 112(4), 296-301.