Domains of chronic stress, lifestyle factors, and allostatic load in middle-aged Mexican-American women

The association of allostasis with alcohol use: A case-control study in males with and without alcohol use disorder

BACKGROUND

Allostatic load (AL) is associated with a heightened predisposition to disease due to prolonged activation of biological stress-response systems. Alcohol use disorder (AUD) is known to activate these systems. The primary aim of the current study was to examine the relationship between AL and AUD.

METHODS

Participants were males (100%) with DSM-IV Alcohol Dependence (n = 48) and healthy participants with no history of substance use disorder (n = 17). Participants with AUD were 4-6 weeks abstinent. The AL index used cortisol, interleukin-6 (IL-6), fibrinogen, tumor necrosis factor-alpha (TNFα), C-reactive protein (CRP), glucose, insulin, leptin, pulse, systolic blood pressure readings, diastolic blood pressure readings, and body mass index (BMI). Physiological dysregulation for each biological measure was determined based on values within the 25th or 75th percentiles; AL was calculated as the total number of physiologically dysregulated biological measures.

RESULTS

No differences in mean AL scores between the cases and controls [t(63) = .48, p = .633] were observed. Among cases, AL was not associated with lifetime drinks per drinking day (F(2,42) = .42, p = .662), lifetime total drinks (F(2,42) = 0.48, p = .620), total drinks 6 months prior to participating in the study (F(2,43) = 0.58, p = .563), or drinks per drinking day at 3-month follow-up (F(2,35) = 1.93, p = .161). AL was negatively associated with drinks per drinking day 6 months prior to study participation (F(2,42) = 3.71, p = .033).

CONCLUSIONS

The hypotheses were not supported. Given that alcohol is likely to lead to physiological dysregulation, the apparent absence of a relationship between biomarkers of cumulative stress as indicated by AL and drinking status was both unanticipated and remarkable. Based on the results, AL in the context of drinking status or drinking among males with AUD may not be applicable.

The allostatic load model: a framework to understand the cumulative multi-system impact of work-related psychosocial stress exposure among firefighters

Firefighting is recognised as a profession where health and well-being can be affected by a variety of occupational factors, such as physical, thermal, and chemical stressors. Along with the risks intuitively associated with the fire service, however, psychosocial stress has begun to attract attention as another variable deserving of consideration. Indeed, long-term exposure to work-related psychosocial stress has been linked with poor health outcomes in many workers; however, despite this association, very little has been done to examine how such stressors become biologically embedded in firefighters. To help facilitate research into how psychosocial stress can affect health-related outcomes in the fire service, we propose a framework centered on the notion of allostatic load. First, we reviewed the occupational characteristics that may generate psychosocial stress within firefighters before introducing allostatic load (that is, dysregulation across various physiological systems caused by the need to manage ongoing stressors). Next, we provided a summary of how allostatic load can be measured and touched on the framework's utility for studying the cumulative effects of work-related stress on firefighter health. After this, factors that may influence the steps leading from stress exposure to health outcomes were discussed; in particular, we commented upon how research in this area should consider specific non-modifiable (age, sex, and ethnicity) and modifiable (psychosocial resources and behavioural habits) factors. Finally, we presented methodological barriers and opportunities that may arise when using the allostatic load framework with this professional group. By introducing the framework, we hope to provide a tool that may be used by those interested in stress-health research in firefighters to build the evidence needed to inform primary prevention measures.

Cumulative physiological stress is associated with age-related changes to peripheral T lymphocyte subsets in healthy humans

BACKGROUND

Progressive age-associated change in frequencies and functional capacities of immune cells is known as immunosenescence. Despite data linking chronic environmental, physiological, and psychosocial stressors with accelerated aging, how stress contributes to immunosenesence is not well characterized.

OBJECTIVE

To help delineate the contribution of cumulative physiological stress on immunosensence we assessed relationships between a composite measurement of cumulative physiological stress, reflecting the functioning of the hypothalamic-pituitary-adrenal axis, sympathetic nervous system, cardiovascular system, and metabolic processes, and lymphocyte changes typically affiliated with aging in a cohort of healthy volunteers ranging from 18 to 66 y.

RESULTS

Physiological stress load positively correlated with subject age in the study cohort and was significantly higher in adults 50-66 y compared to adults 18-33 y and 34-49 y. Using physiological stress load, we identified a significant age-dependent association between stress load and frequencies of circulating regulatory T lymphocytes (Tregs). Frequencies were higher in younger participants, but only in participants exhibiting low physiological stress load. As stress load increased, frequencies of Tregs decreased in young participants but were unchanged with increasing stress load in middle and older age individuals. Follow-up analysis of stress load components indicated lower circulating DHEA-S and higher urinary norepinephrine as the primary contributors to the effects of total stress load on Tregs. In addition, we identified age-independent inverse associations between stress load and frequencies of naïve Tregs and naïve CD4 T cells and positive associations between stress load and frequencies of memory Tregs and memory CD4 T cells. These associations were primarily driven by stress load components waist circumference, systolic and diastolic blood pressure, CRP, and HbA1c. In summary, our study results suggest that, in younger people, physiological stress load may diminish regulatory T cell frequencies to levels seen in older persons. Furthermore, independent of age, stress load may contribute to contraction of the naïve Treg pool and accumulation of memory Treg cells.

CLINICAL TRIAL

Registered on ClincialTrials.gov (Identifier: NCT02367287).

Physical activity is associated with allostatic load: Evidence from the National Health and Nutrition Examination Survey

We determined the associations between physical activity and allostatic load, and whether it is a modifiable factor related to allostatic load. We obtained data from the National Health and Nutrition Examination Survey (NHANES) database collected between 2017 and March 2020. The relationship between physical activity and allostatic load was examined using a logistic regression model. In the unadjusted model, physical activity level was associated with allostatic load index (odds ratio [OR] = 0.664, 95% confidence interval [CI]: 0.550, 0.802, P＜0.001), with this relationship being retained in the adjusted model (OR = 0.739, 95%CI: 0.603, 0.907; P = 0.004). Sedentary behaviour was also related to allostatic load index (OR = 1.236, 95%CI: 1.005, 1.520; P = 0.044). Our findings indicated that sufficient physical activity is associated with a lower allostatic load index, and sedentary behaviour is associated with a higher allostatic load index. Physical activity is a modifiable factor related to allostatic load.

The role of combined modifiable lifestyle behaviors in the longitudinal association between stressful life events and allostatic load in Australian adults

Allostatic load is a model that is used to quantify the physiological damage from exposure to stressors. Stressful life events are chronic stressors that can lead to an elevated allostatic load through the physiological and behavioral stress responses. However, there is limited empirical studies that has tested the proposed behavioural pathway. Our study addresses this gap by examining the mediating role of combined modifiable lifestyle behaviors in the 12-years longitudinal association between stressful life events and allostatic load among participants from the Australian Diabetes, Obesity and Lifestyle (AusDiab) Study cohort. A latent profile analysis was performed to identify latent subgroups with distinct behavioral clusters based on five modifiable lifestyle behaviors (smoking, sedentary behavior, physical activity, alcohol consumption, and diet quality). We then used a sequential mediation model design with path analysis to test the mediating effect of these latent subgroups in the associations between stressful life events and three measures of allostatic load. Indirect effects were estimated using the product of coefficient approach and the statistical significance was determined by the 95% bias-corrected bootstrap confidence intervals with 1000 replications. We identified three latent subgroups: "least healthy lifestyle" (12%; n = 396), "moderately healthy lifestyle" (78.7%; n = 2599), and "most healthy lifestyle" (9.2%; n = 306). Exposure to stressful life events was not associated with the allocation of participants in latent subgroups. Compared to the "moderately healthy lifestyle" subgroups, we found that the "least healthy lifestyle" behavioral cluster was not associated with allostatic load. However, there was a significant inverse association between the "most healthy lifestyle" behavioral cluster and allostatic load. Overall, we did not find significant indirect effects between stressful life events and three measures of allostatic load via the "least healthy lifestyle" and the "most healthy lifestyle" groups. In summary, the combinations of modifiable lifestyle behaviors did not explain the association between stressful life events and allostatic load. More longitudinal studies are needed to replicate our study to confirm this finding.

Allostatic Load Measurement: A Systematic Review of Reviews, Database Inventory, and Considerations for Neighborhood Research

BACKGROUND

Neighborhoods are critical to understanding how environments influence health outcomes. Prolonged environmental stressors, such as a lack of green spaces and neighborhood socioeconomic disadvantage, have been associated with higher allostatic load levels. Since allostatic load levels experienced earlier in life have stronger associations with mortality risk, neighborhoods may be uniquely suited to monitor and mitigate the impacts of environmental stressors. Researchers often study allostatic load in neighborhoods by utilizing administrative boundaries within publicly accessible databases as proxies for neighborhoods.

METHODS

This systematic review of reviews aims to identify commonly used biomarkers in the measurement of allostatic load, compare measurement approaches, inventory databases to study allostatic load, and spotlight considerations referenced in the literature where allostatic load is studied in neighborhoods. The review was conducted using the search term "allostatic load" in the MEDLINE, CINAHL, and PsychINFO databases. The search results were filtered to include reviews.

RESULTS

The search returned 499 articles after deduplication. Overall, 18 synthesis reviews met the inclusion criteria and were retained for extraction. The synthesis reviews analyzed represented 238 studies published from 1995 to 2020. The original ten biomarkers were most often used to measure allostatic load. More recently, body mass index and C-reactive protein have additionally been frequently used to measure allostatic load burden.

CONCLUSIONS

The scientific contributions of this study are that we have identified a clear gap in geographic considerations when studying allostatic load. The implication of this study is that we have highlighted geographic concepts when conducting neighborhood-level research using administrative databases as a neighborhood proxy and outlined emerging future trends that can enable future study of allostatic load in the neighborhood context.

Association of Allostatic Load and All Cancer Risk in the SWAN Cohort

Elevated chronic stress is thought to increase cancer risk, though the results so far have been inconsistent. In this study, we assessed the relationship between allostatic load (AL), a biological indicator of chronic stress, and overall cancer risk in 3015 women who participated in the Study of Women’s Health Across the Nation (SWAN). Based on the distribution of AL, the study population was categorized into four groups, from the lowest (1st category) to the highest AL group (4th category). At baseline, African American and Hispanic women were more likely to be in the higher AL categories than White women (p < 0.001). In addition, women who smoked regularly, drank alcohol regularly, had no leisure physical activity, and had restless sleep were also more likely to be in the higher AL categories than their relative counterparts (p < 0.001). We also observed that women in the lower-income category with no health insurance were more likely to be in the higher AL category (p < 0.001). The study then found that women in the 4th category of AL (the highest AL group) had a 1.64-fold increased risk of overall cancer (Hazard ratio (HR): 1.64, 95% confidence interval (CI): 1.04, 2.59). The risk association was further strengthened after adjusting demographics, healthy behaviors, and socioeconomic factors with an HR of 2.08. In further analysis of individual biomarkers of AL score, we found that higher levels of triglyceride and CRP were associated with increased risk of cancer, highlighting the role of metabolic dysfunction and inflammation in the etiology of cancer development. In summary, we report that higher AL is associated with increased cancer risk.

Dimensions of acculturation and biological dysregulation among Latina/os: the role of ethnic background, gender, and immigrant generation

Objective: Research examining how different dimensions of acculturative beliefs and behaviors influence the risk of biological dysregulation among Latina/os is limited. This study examined associations between three types of acculturation and allostatic load (i.e. a multisystem index of biological dysregulation) across gender and Latina/o ethnic groups. Multiplicative models were also included in order to determine whether immigrant generation moderates acculturation-allostatic load relationships.Design: Data were drawn from the Hispanic Community Health Study/ Study of Latina/os. The sample consisted of 11,841 Latina/os from five ethnic groups: Cuban, Puerto Rican, Dominican, Mexican, and South/Central American. The measure for allostatic load was derived from 15 biomarker and anthropometric measures that were designed to capture cardiometabolic risk, glucose metabolism, cardiopulmonary function, inflammation, and organ function. Acculturation measures, immigrant generation, gender, ethnic background, and other covariates were derived from self-reports. Survey corrected ordinary least squares regressions were used to assess relationships between different dimensions of acculturation and allostatic load.Results: Results demonstrate dimensions of acculturation play a significant role in the risk of biological dysregulation for Latina/os with divergent results across gender and ethnic background. Estimates from the multiplicative models show immigrant generation moderates acculturation-allostatic load relationships, and relationships are dependent on gender and ethnic background.Conclusion: The study contributes to the understanding of how different dimensions of acculturation, as well as other important structural determinants of health, influence the risk of biological dysregulation among Latina/os. Finding from this study can inform targeted strategies designed to reduce the physiological consequences of chronic stress among Latina/os.

The role of combined modifiable lifestyle behaviors in the association between exposure to stressors and allostatic load: A systematic review of observational studies

BACKGROUND

Exposure to stressors can evoke psychological, physiological, and behavioral stress responses, which may lead to the adoption of health-damaging behaviors that dysregulate multiple biological systems contributing to a high allostatic load. This review explored the role of combined modifiable lifestyle behaviors in the relationship between stressors and allostatic load among healthy adults.

METHODS

A systematic search was conducted in Medline Complete, PsycINFO, CINAHL, and Embase databases up to September 2021. The PRISMA guidelines guided reporting and study quality was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Checklist.

RESULTS

Database searches identified 319 papers. Eight cross-sectional and two longitudinal studies met our inclusion criteria. Among the ten studies, combined modifiable lifestyle behaviors partly explained the association between exposure to stressors and elevated allostatic load in four cross-sectional and two longitudinal studies.

CONCLUSION

Some evidence suggests that combined modifiable lifestyle behaviors may help explain the relationship between stressors and an elevated allostatic load. Further longitudinal studies with mediation analyses would strengthen these findings and help to confirm the mechanistic role of combined modifiable lifestyle behaviors underlying the relationship between stress exposure and allostatic load.

Energy intake and season interact to influence physiological stress load among midlife women

Allostatic load (AL) is an index that measures physiologic stress associated with chronic disease risk. One factor that may influence overall physiologic stress load and AL is energy consumption, but whether this association differs across different seasons is unknown. We tested whether energy consumption interacted with the season to influence AL in 52 mid-life (40-60 years) women from the Life in All Seasons Study. Women completed an online 24-h recall every 10 days and had components of allostatic load measured seasonally. Women were from the greater Grand Forks, ND catchment area and were followed for one year between July 2012 and July 2014. We found a significant (p = 0.01) interaction between season and energy consumption on AL. Further inspection showed that, during the summer and winter seasons, the average allostatic load rose with relatively higher energy consumption. We also observed a linear and positive association between AL and energy intake in summer (β = 0.0013 ± 0.0004; p = 0.001; r² = 0.14) and winter (β = 0.0011 ± 0.0004; p = 0.007; r² = 0.10), but not in fall or spring. These results suggest that factors associated with distinct times of the year promote or prevent the effects of higher energy consumption on physiological stress load. Since allostatic load is linked to elevated disease risk, our results provide additional information that may help to explain seasonal differences in disease risk of some women.

Allostatic Load and Its Impact on Health: A Systematic Review

INTRODUCTION

Allostatic load refers to the cumulative burden of chronic stress and life events. It involves the interaction of different physiological systems at varying degrees of activity. When environmental challenges exceed the individual ability to cope, then allostatic overload ensues. Allostatic load is identified by the use of biomarkers and clinical criteria.

OBJECTIVE

To summarize the current knowledge on allostatic load and overload and its clinical implications based on a systematic review of the literature.

METHODS

PubMed, PsycINFO, Web of Science, and the Cochrane Library were searched from inception to December 2019. A manual search of the literature was also performed, and reference lists of the retrieved articles were examined.We considered only studies in which allostatic load or overload were adequately described and assessed in either clinical or non-clinical adult populations.

RESULTS

A total of 267 original investigations were included. They encompassed general population studies, as well as clinical studies on consequences of allostatic load/overload on both physical and mental health across a variety of settings.

CONCLUSIONS

The findings indicate that allostatic load and overload are associated with poorer health outcomes. Assessment of allostatic load provides support to the understanding of psychosocial determinants of health and lifestyle medicine. An integrated approach that includes both biological markers and clinimetric criteria is recommended.

Is the Association Between Education and Sympathovagal Balance Mediated by Chronic Stressors?

Background

This study investigated whether raised chronic stress in low education groups contributes to education differences in cardiovascular disease by altering sympathovagal balance.

Methods

This study included cross-sectional data of 10,202 participants from the multi-ethnic, population-based HELIUS-study. Sympathovagal balance was measured by baroreflex sensitivity (BRS), the standard deviation of the inter-beat interval (SDNN) and the root mean square of successive differences between normal heartbeats (RMSSD). The associations between chronic stressors (work, home, psychiatric, financial, negative life events, lack of job control and perceived discrimination) in a variety of domains and BRS, SDNN and RMSSD were assessed using linear regression, adjusted for age, ethnicity, waist-to-hip ratio and pack-years smoked. Mediation analysis was used to assess the contribution of chronic stress to the association between education and sympathovagal balance.

Results

Modest but significant associations were observed between financial stress and BRS and SDNN in women, but not in RMSSD nor for any outcome measure in men. Women with the highest category of financial stress had 0.55% lower BRS (ms/mmHg; β = -0.055; CI = -0.098, -0.011) and 0.61% lower SDNN (ms; β = -0.061; CI = -0.099, -0.024) than those in the lowest category. Financial stress in women contributed 7.1% to the association between education and BRS, and 13.8% to the association between education and SDNN.

Conclusion

No evidence was found for the hypothesized pathway in which sympathovagal balance is altered by chronic stress, except for a small contribution of financial stress in women.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12529-021-10027-9.

Chronic stress exposure in men and women, and implications for the course of fatigue after percutaneous coronary intervention; the THORESCI study

BACKGROUND

Fatigue is a prevalent symptom in patients with coronary heart disease (CHD). Individual differences in chronic stress may affect the experience and persistence of fatigue, and this may vary between the sexes. Therefore, we studied the effect of chronic stress on the course of fatigue over a 2-year period after percutaneous coronary intervention (PCI), and examined the moderating effects of sex.

METHODS

1682 patients (78% men, age = 67.1 ± 10.6) were recruited and filled out multiple self-report questionnaires at baseline, one, 12, and 24 months post-PCI, including questions on demographics, fatigue (HCS). Multiple chronic stressors were assessed at baseline: work stress (ERI16), marital stress (MMQ-6), early life events (Life Events Questionnaire) and social stress. Latent class factor analysis (LatentGOLD) was used to construct a comprehensive chronic stress index. Linear mixed modeling examined the predictive quality of predictors and covariates.

RESULTS

Fatigue was found to substantially decrease over the first month post-PCI, then stabilized at a moderate level. Chronic stress impacted both the level and course of fatigue by increasing its level and delaying recovery. Overall and across time, women reported more fatigue than men. The level and course effects of chronic stress and sex were independent of demographic, health behavioral, and medical covariates.

CONCLUSIONS

Individual differences in chronic stress impact both the level and course of fatigue post-PCI, with women being affected most. Future research could further explain the mechanisms underlying the observed relationships. Developing and testing interventions focusing on exercise and stress-reduction could be used to alleviate fatigue.

Association between physiological stress load and diet quality patterns differs between male and female adults

A promising, yet relatively unexplored factor that may influence a person's stress response, is diet. Diet can affect the physiological response to stress, but relationships between diet quality and the chronic stress marker allostatic load (AL) are insufficiently studied. Furthermore, sex, age, and BMI may interact with diet quality to influence AL. 358 adults were recruited across predetermined sex, age, and BMI ranges. Cluster analysis of 13 Healthy Eating Index (HEI) sub-scores across all participants revealed six distinct diet quality patterns (HEI-P). We found sex and HEI-P interacted (P_HEIxSex = 0.0232) to affect AL, reflecting a significantly different AL between women and men consuming a diet more closely aligned with the Dietary Guidelines for Americans for dairy, refined grains, and sodium consumption, but less aligned for added sugar, saturated fat, and fruits/vegetables intake. Sex and HEI-P also interacted to affect cholesterol (P_HEIxSex = 0.0157), norepinephrine (P_HEIxSex = 0.0315), epinephrine (P_HEIxSex = 0.0204), and systolic blood pressure (P_HEIxSex = 0.0457) but, compared to total allostatic load, no individual component of this biomarker explained the entire array of sex by HEI-P interactions. Our results suggest that differences in HEI-P and sex interact to influence physiological stress load which, in turn, may help resolve discrepancies in diet and sex-related disease risk.

Association between health behaviours and cardiometabolic dysregulation: a population-based survey among healthy adults in Hong Kong

OBJECTIVE

To explore the association between cardiometabolic dysregulation, an integral component of allostatic load, and health risk behaviours (HRBs) of the Hong Kong healthy adult population.

DESIGN

Secondary analysis of cross-sectional anonymous data.

SETTING

Data on sociodemographics, self-reported health status, HRBs and biomarkers were extracted from the Hong Kong Population Health Survey 2014/2015.

PARTICIPANTS

One thousand five hundred and fifty-one participants aged 18-64 years without self-reported diagnoses of hypertension, diabetes mellitus, hyperlipidaemia, cardiovascular disease, cognitive impairment or cancer.

PRIMARY OUTCOME MEASURES

Cardiometabolic dysregulation index (CMDI), ranging from 0 to 6, was calculated by counting the number of biomarkers including systolic blood pressure, diastolic blood pressure, waist to hip ratio, glycated haemoglobin, total cholesterol to high-density lipoprotein cholesterol ratio, and triglycerides that were above the respective normal level suggested by international guidelines and literature. HRBs including smoking, dietary habits and sleeping hours were collected by self-report questionnaire. Alcohol consumption was assessed by the 10-item Alcohol Use Disorders Identification Test, while physical activity level was measured using the Global Physical Activity Questionnaire. A composite HRB score, ranging from 0 to 5, was calculated as the cumulative number of HRBs. The effect of HRB on CMDI was evaluated by negative binomial regression with adjustment for socioeconomic status, health awareness and comorbidities of the participants.

RESULTS

The mean CMDI of the studied population was 1.6; 29.5% had a CMDI of 0, whereas 1.5% had a CMDI of 6. Significant difference was observed in mean CMDI between gender and different age groups. Sleeping less than 6 hours (incidence rate ratio (IRR)=1.26, p<0.001), smoking (IRR=1.15, p=0.027), insufficient physical activity (IRR=1.12, p=0.007) and higher composite HRB score (IRR=1.12, 95% CI 1.06 to 1.18) were significantly associated with higher CMDI.

CONCLUSION

Smoking, physical inactivity and inadequate sleep-an essential yet often overlooked health behaviour-were associated with higher CMDI in the Hong Kong healthy adult population.

A Systematic Review of Physical Health Consequences and Acculturation Stress Among Latinx Individuals in the United States

The health of Latinx immigrants decays over time and across generations. Acculturation stress influences decays in behavioral and mental health in this population, but the effect on physical health outcomes is less understood. This systematic review synthesizes findings from 22 studies that examined the influence of acculturation stress on physical health outcomes among Latinx populations in the United States. The Society-to-Cell Resilience Framework was used to synthesize findings according to individual, physiological, and cellular levels. There is mounting evidence identifying acculturation stress as an important social contributor to negative physical health outcomes, especially at the individual level. More research is needed to identify the physiological and cellular mechanisms involved. Interventions are also needed to address the damaging effects of acculturation stress on a variety of physical health conditions in this population.

Technician-Scored Stool Consistency Spans the Full Range of the Bristol Scale in a Healthy US Population and Differs by Diet and Chronic Stress Load

BACKGROUND

Prior studies of adults with constipation or diarrhea suggest that dietary intake, physical activity, and stress may affect stool consistency. However, the influence of these factors is unresolved and has not been investigated in healthy adults.

OBJECTIVES

We assessed the relations of technician-scored stool consistency in healthy adults with self-reported diet, objectively monitored physical activity, and quantifiable markers of stress.

METHODS

Stool consistency was scored by an independent technician using the Bristol Stool Form Scale (BSFS) to analyze samples provided by healthy adults, aged 18-65 y, BMI 18-44 kg/m2, in the USDA Nutritional Phenotyping Study (n = 364). A subset of participants (n = 109) were also asked to rate their sample using the BSFS. Dietary intake was assessed with two to three 24-h recalls completed at home and energy expenditure from physical activity was monitored using an accelerometer in the 7-d period preceding the stool collection. Stress was measured using the Wheaton Chronic Stress Inventory and allostatic load (AL). Statistical and machine learning analyses were conducted to determine which dietary, physiological, lifestyle, and stress factors differed by stool form.

RESULTS

Technician-scored BSFS scores were significantly further (P = 0.003) from the central score (mean ± SEM distance: 1.41 ± 0.089) than the self-reported score (1.06 ± 0.086). Hard stool was associated with higher (P = 0.005) intake of saturated fat (13.8 ± 0.40 g/1000 kcal) than was normal stool (12.5 ± 0.30 g/1000 kcal). AL scores were lower for normal stool (2.49 ± 0.15) than for hard (3.07 ± 0.18) (P = 0.009) or soft stool (2.89 ± 0.18) (P = 0.049). Machine learning analyses revealed that various dietary components, physiological characteristics, and stress hormones predicted stool consistency.

CONCLUSIONS

Technician-scored stool consistency differed by dietary intake and stress hormones, but not by physical activity, in healthy adults.This trial was registered at clincialtrials.gov as NCT02367287.

Stress and Allostatic Load Among Latina/os: Evidence from the Hispanic Community Health Study/Study of Latina/os

We investigated associations between measures of environmental and psychological stress (i.e., chronic stress and perceived stress) and allostatic load across gender. We also tested whether other important intersectional factors, such as ethnic background and nativity, moderated stress-allostatic load relationships. Data were drawn from the Hispanic Community Health Study/ Study of Latina/os, a representative, multi-ethnic sample of Latina/os living in four urban communities. The final analytic sample consisted of 3848 Latina/os from five ethnic groups: Cuban, Puerto Rican, Dominican, Mexican, and South/ Central American. Findings indicate greater chronic and perceived stress were significantly associated with allostatic load for males but not for females. We also find, in some cases, ethnic background and nativity moderated relationships between types of stress and allostatic load for males. Findings suggest that environmental and psychological stressors can potentially shape health profiles of Latino males, with important differences across ethnic background and nativity.

Allostatic score and its associations with demographics, healthy behaviors, tumor characteristics, and mitochondrial DNA among breast cancer patients

INTRODUCTION

Allostatic load (AL), a composite index, has been used to capture variation in life-course stresses. However, few studies have been carried out among breast cancer patients.

METHODS

In this study, we examined the cross-sectional association of AL with demographics, healthy behaviors, tumor characteristics, and mitochondrial DNA copy number in breast cancer patients. The study used a sub-sample of 934 women with newly diagnosed breast cancer at M.D. Anderson from 2013 to 2018. To construct the AL score, the study used a battery of seventeen factors that represents the activity of five physiological systems: metabolic, cardiovascular, immunological, renal, and liver.

RESULTS

AL was positively associated with the age of disease diagnosis (P = 0.002), and was higher in Black and Hispanic populations than White (P = 0.001 and 0.032, respectively). AL was also found more abundant in those who experienced marital dissolution (P = 0.006), lacked a college education (P = 0.045), currently smoked (P = 0.011), and had low levels of physical activity (P = 0.037) than their counterparts. The study then found that higher AL was associated with increased odds of having poorly differentiated tumors (Odds ratio (OR): 1.40, 95% confidence interval (CI): 1.28, 1.62). An additional significant association was observed between AL with estrogen receptor negative (ER-) (OR = 1.56, 95%CI: 1.02, 2.36) among Black patients. Finally, we observed a significant positive correlation between AL with leukocyte mitochondrial DNA copy number variation (P < 0.001).

CONCLUSIONS

We conclude AL is influenced by selected demographics and healthy behaviors, and further is correlated with tumor characteristics and mitochondrial DNA copy number in breast cancer patients.

Social Risk Factors for Medication Nonadherence: Findings from the CARDIA Study

Objectives: Nonadherence to medications has been documented, but the combined effect of social risk factors on medication nonadherence has not been investigated. Methods: We conducted a cross-sectional analysis of data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, a population-based prospective cohort. The sample (N = 1506) included subjects who at Year 20 (2005-06) were taking prescription medications and completed a 4-item Medication Adherence Scale. Social risk factors were education of high school or less, annual household income <$25,000, high financial strain, high chronic stress, low social support, and high social strain. Results: In a fully adjusted logistic regression model, income <$25,000 (OR = 2.37 [95% CI 1.12-4.98], p < .05) and high chronic stress (OR = 2.07 [95% CI 1.09-3.94], p < .05) were significantly associated with medication nonadherence. Individuals with ≥3 social risk factors had >3 times higher odds of nonadherence than counterparts with no social risk factors (OR = 3.26 [95% CI 1.72-6.19], p < .001). Conclusion: Low income and chronic stress are associated with medication nonadherence, and the odds of nonadherence increase with the accumulation of social risk factors. Findings may be used to develop risk prediction tools to identify individuals who can benefit from adherence-promoting interventions.

A time to be chronically stressed? Maladaptive time perspectives are associated with allostatic load

Living in the past, the present, or the future can affect stress and health. Our group has shown that acute stress (cortisol reactivity) is modulated by time perspectives, the ways we psychologically relate to time. Here, we expand this research with a comprehensive measure of multi-systemic chronic stress (allostatic load). Among 204 healthy adults (60 men; 144 women), we examined whether time perspectives modulate allostatic load measured with 23 neuroendocrine, immune, metabolic, and cardiovascular biomarkers. Five time perspective categories were measured (past negative, past positive, present hedonistic, present fatalistic, future). Multiple regressions controlling for sex, age, and depressive symptoms were used. Increased present fatalistic time perspective was positively correlated with allostatic load, while future time perspective was negatively correlated with allostatic load. Our preliminary findings link time perspective to multisystemic chronic stress and are discussed in the context of potential clinical implications.

Financial strain and ideal cardiovascular health in middle-aged and older women: Data from the Women's health study

Financial strain is a prevalent form of psychosocial stress in the United States; however, information about the relationship between financial strain and cardiovascular health remains sparse, particularly in older women.

METHODS

The cross-sectional association between financial strain and ideal cardiovascular health were examined in the Women's Health Study follow-up cohort (N = 22,048; mean age = 72± 6.0 years).Six self-reported measures of financial strain were summed together to create a financial strain index and categorized into 4 groups: No financial strain, 1 stressor, 2 stressors, and 3+ stressors. Ideal cardiovascular health was based on the American Heart Association strategic 2020 goals metric, including tobacco use, body mass index, physical activity, diet, blood pressure, total cholesterol and diabetes mellitus. Cardiovascular health was examined as continuous and a categorical outcome (ideal, intermediate, and poor). Statistical analyses adjusted for age, race/ethnicity, education and income.

RESULTS

At least one indicator of financial strain was reported by 16% of participants. Number of financial stressors was associated with lower ideal cardiovascular health, and this association persisted after adjustment for potential confounders (1 financial stressor (FS): B = -0.10, 95% Confidence Intervals (CI) = -0.13, -0.07; 2 FS: B = -0.20, 95% CI = -0.26, -0.15; 3+ FS: B = -0.44, 95% CI = -0.50, -0.38).

CONCLUSION

Financial strain was associated with lower ideal cardiovascular health in middle aged and older female health professional women. The results of this study have implications for the potential cardiovascular health benefit of financial protections for older individuals.

Factor Structure for Chronic Stress Before and During Pregnancy by Racial/Ethnic Group

This study aimed to explore race/ethnicity-specific dimensionalities of chronic stress before and during pregnancy for non-Hispanic (N-H) White, N-H Black, Hispanic, and Asian women in the United States. This study analyzed the data among 6,850 women from the New York City and Washington State Pregnancy Risk Assessment Monitoring System (2004-2007) linked with birth certificates. Separate exploratory factor analysis was conducted by race/ethnicity using a maximum-likelihood extraction method with 26 chronic stress items before and during pregnancy. Correlations and internal consistency reliabilities among items and latent factors determined race/ethnicity-specific factor structures of chronic stress. Chronic stress was race/ethnicity-distinctive and multidimensional with low correlations among the factors ( r = .07-.28, p < .05). Despite financial hardship, perceived isolation, and physical violence underlying chronic stress among the racial/ethnic groups, intergroup variations existed under each group's cultural or sociopolitical contexts. This study could help develop targeted strategies to intervene with women's chronic stressors before childbirth.

Acculturation stress and allostatic load among Mexican immigrant women

OBJECTIVES

this case-control study compared levels of stress and allostatic load (AL) among Mexican women in the US ( n =19) and Mexico ( n = 40).

METHOD

measures of stress included the Perceived Stress Scale (PSS) and the Hispanic Women's Social Stressor Scale (HWSSS). A composite measure of 8 indicators of AL (systolic and diastolic blood pressure, body mass index (BMI), waist-to-hip ratio, total cholesterol, glycated hemoglobin (hemoglobin A1C), triglycerides and C-reactive protein) was calculated.

RESULTS

there were no significant group differences in AL between Mexican and Mexican immigrant women ( t = 1.55, p = .126). A principal component factor analysis was conducted on the 8 AL indicators; a 2-factor solution explained 57% of the variance. Group differences in the two AL factors were analyzed using MANOVA. BMI and waist-to-hip ratios were lower, but blood pressure and triglycerides were higher in the US group and were mediated by time in the US. Greater acculturation stress was significantly related to increased waist-to-hip ratio ( r = .57, p = .02).

FINAL REMARKS

findings suggest some measures of AL increased with time in the US, and acculturation stress may be a significant factor.

Allostatic Load: Importance, Markers, and Score Determination in Minority and Disparity Populations

Allostatic load is a physiological measure of the cumulative burden of stress on the body assessed by markers of physiological dysregulation. It is a multisystem construct that quantifies biological risk which leads to poor health and maladaptive trajectories. In this overview, which is based on a presentation made at the Flip the Script: Understanding African American Women's Resilience in the Face of Allostatic Load meeting at Ohio State University in August 2018, we build upon previous reviews by discussing four key aspects of allostatic load, specifically its: (1) importance, (2) operationalization, (3) use in minority health and health disparities research, and (4) value in such research. Operationalized in various ways, allostatic load is composed of 10 original markers and additional markers deriving from research among minority and disparity populations. The markers represent four biological systems: (1) cardiovascular, (2) metabolic, (3) inflammatory, and (4) neuroendocrine. System-specific racial/ethnic and sex-based differences have been observed. An overall score can be determined using sample-generated or empirically derived clinically relevant cut points. In summary, allostatic load provides an overall and a body system-specific mechanistic link between exposures to stressors and health outcomes that may help explain health disparities among minority populations.

Diet Quality for Sodium and Vegetables Mediate Effects of Whole Food Diets on 8-Week Changes in Stress Load

Very little is known about how whole food diets, such as those based on the Dietary Guidelines for Americans (DGA), influence psychological stress and physiological stress load. To better understand the effects of whole food diets on stress, we examined in a randomized control trial the effects of a DGA-based diet on markers of psychological and physiological stress. A randomized, double-blind, controlled 8-week intervention was conducted in overweight and obese women randomly assigned to one of two diet groups: a diet based on the 2010 DGA or a diet based on a Typical American Diet (TAD). The Perceived Stress Scale and allostatic load were used to assess stress load. Eight-week change in perceived stress did not significantly (p = 0.45) differ between the DGA (+0.53 ± 0.99) and TAD (-0.57 ± 0.99) groups. Likewise, 8-week change in allostatic load did not significantly (p = 0.79) differ between the two diet intervention groups (DGA: +0.001 ± 0.26 vs. TAD: +0.105 ± 0.28). However, we did find strong inverse associations between 8-week change in stress and intervention-based improvements in diet quality (lower sodium and higher vegetable consumption). When statistically accounting for these inverse associations, we found that perceived stress and allostatic load were higher (p < 0.04) in the DGA group. These findings suggest that improvements in dietary vegetable and sodium intake mediated effects of the diet intervention on psychological and physiological stress load. That is, adopting and adhering to a diet of higher quality (DGA) for 8 weeks may have been generally more stressful in the absence of improvements in vegetable or sodium consumption. This study provides further evidence for the mental health benefits of maximizing vegetable and minimizing sodium consumption.

Cross-border ties, nativity, and inflammatory markers in a population-based prospective study of Latino adults

Even after migration, immigrants and their descendants may continue to have ties to family and friends who remain in places of origin. Recent research suggests that these cross-border social ties have implications for health, although this scholarship has been limited to self-reported outcomes. Using data from the Sacramento Area Latino Study on Aging (SALSA), we estimate associations between cross-border social ties and inflammatory biomarkers among Latino adults (n = 1786). We find that immigrants who maintained any cross-border connection to family and friends in Latin America had significantly lower levels of baseline interleukin-6 (IL-6) and C-reactive protein (CRP) compared to their US-born counterparts with no cross-border ties. These results held for values of CRP at five-year follow-up for men only. In contrast, US-born women with cross-border ties to family and friends in Latin America had both significantly higher levels of CRP and significantly lower levels of tumor necrosis factor-alpha (TNF-α) at five-year follow-up relative to their US-born counterparts with no cross-border ties. We find descriptively that men who have cross-border ties are also less likely to be socially isolated within local contexts. Considering place-of-origin social connections may contribute critical nuance to studies of immigrant health, including disparities in inflammatory markers that may serve as indicators of underlying chronic disease.

Sociocultural variability in the Latino population: Age patterns and differences in morbidity among older US adults

BACKGROUND

The US Latino population is rapidly aging and becoming increasingly diverse with respect to nativity and national origin. Increased longevity along with medical advancements in treatment have resulted in a higher number of older Latinos living with morbidity. Therefore, there is a need to understand variability in Latino health among older adults.

OBJECTIVES

This paper documents mid- and late-life health differences in morbidity by race/ethnicity, nativity, and country of origin among adults aged 50 and older.

METHODS

We use data from the 2000-2015 National Health Interview Survey to calculate age-and gender-specific proportions based on reports of five morbidity measures: hypertension, heart disease, stroke, cancer, and diabetes among non-Latino Whites and seven Latino subgroups.

RESULTS

The foreign-born from Mexico, Cuba, and Central/South America, regardless of gender, exhibit an immigrant advantage for heart disease and cancer in comparison to non-Latino Whites across all age categories. Conversely, island-born Puerto Ricans are generally characterized with higher levels of morbidity. Similarly, US-born Puerto Ricans and Mexicans exhibit morbidity patterns indicative of their minority status. Latinos, regardless of gender, were more likely to report diabetes than non-Latino Whites. Hypertension and stroke have significant variability in age patterns among US-and foreign-born Latinos.

CONCLUSION

Recognizing the importance of within-Latino heterogeneity in health is imperative if researchers are to implement social services and health policies aimed at ameliorating the risk of disease.

CONTRIBUTION

Considering intersectional ethnic, nativity, and country-of-origin characteristics among older Latinos is important to better understand the underlying causes of racial/ethnic disparities in morbidity across the life course.

The association of posttraumatic stress disorder and chronic medical conditions by ethnicity

Our study extends the literature on associations between posttraumatic stress disorder (PTSD) and chronic medical conditions by assessing differences in the magnitude of these relations by ethnicity. We examined group differences in the magnitude of the relation between PTSD and chronic medical conditions (cardiovascular disease [CVD], hypertension, obesity, diabetes). We obtained data from Latino (n = 3,224) and non-Latino white (n = 4,180) respondents from the Collaborative Psychiatric Epidemiology Surveys. Logistic regression models were constructed to test for the modification of the effect of PTSD on chronic medical conditions by ethnicity, and then by nativity. Unadjusted models revealed significant interactions between Latino ethnicity and PTSD for odds of diabetes (OR = 2.18 [Latino] v. 0.81 [non-Latino white]), CVD (OR = 3.23 [Latino] v. 1.28 [non-Latino white]), and hypertension (OR = 1.61 [Latino] v. 0.98 [non-Latino white]). Among U.S.-born Latinos, we found a significant interaction between ethnicity and PTSD for odds of CVD (OR = 4.18 [Latino] v. 1.28 [non-Latino white]) and diabetes (OR = 2.27 [Latino] v. 0.81 [non-Latino white]). These findings attenuated in adjusted models with the exception of differences in PTSD and odds of diabetes among Latinos (including aggregated group & U.S.-born) compared to non-Latino whites. Our findings support the need for further research on the complex relations between PTSD and chronic conditions, including the investigation of conditional risk by Latino sub-groups.

Relationship between stress coping and sleep disorders among the general Japanese population: a nationwide representative survey

OBJECTIVE

To clarify the prevalence of stress, and examine the relationship between sleep disorders and stress coping strategies among highly stressed individuals in the general Japanese population.

METHODS

A cross-sectional nationwide survey was undertaken in November 2007. Men and women were randomly selected from 300 districts throughout Japan. Data from 7671 (3532 men (average age 53.5 ± 17.0 years) and 4139 women (average age 53.9 ± 17.7 years)) were analyzed. Participants completed a self-reported questionnaire on stress, sleep disorders, and stress coping strategies in the previous month.

RESULTS

Highly stressed individuals comprised 16.6% (95% confidence interval 15.8-17.5%) of the total sample, and most were aged 20-49 years. In multiple logistic regression, symptoms of insomnia (ie, difficulty initiating sleep, difficulty maintaining sleep, and early morning awakening), excessive daytime sleepiness, nightmares, daytime malfunction, and lack of rest due to sleep deprivation were more prone to occur in highly stressed individuals. In addition, logistic regression analysis controlling for other adjustment factors revealed that stress coping strategies such as 'giving up on problem-solving', 'enduring problems patiently', 'smoking' and 'drinking alcohol' were positively associated with the above-mentioned sleep disorders. On the other hand, stress coping strategies such as 'exercising', 'enjoying hobbies', and 'sharing worries' were inversely associated with the above-mentioned sleep disorders.

CONCLUSIONS

Distraction-based stress coping (eg, hobbies, exercise, and optimistic thinking) was found to be preferable to problem-based stress coping in a highly stressed Japanese general population.

Chronic Stress and C-Reactive Protein in Mothers During the First Postpartum Year

OBJECTIVE

Elevated levels of C-reactive protein (CRP) are associated with increased risk of cardiovascular and metabolic disease. The current study tested associations between psychosocial stress and CRP in a large sample of women during the first postpartum year.

METHODS

We analyzed data collected by the five-site Community Child Health Network study, which studied a predominately poor population. Participants (n = 1206 women; 54% African American, 23% white, 23% Hispanic/Latina) were recruited shortly after the birth of a child. Multiple linear regression analyses tested associations of psychosocial stress in several life domains (financial, neighborhood, family, coparenting, partner relationship, discrimination, and interpersonal violence) with log-transformed CRP concentrations at 6-month and 1-year postpartum.

RESULTS

Forty-eight percent of participants showed evidence of elevated CRP (≥3 mg/L) at 6-month postpartum, and 46% had elevated CRP at 12-month postpartum. Chronic financial stress at 1-month postpartum predicted higher levels of CRP at 6- (b = .15, SE = .05, p = .006) and 12-month postpartum (b = .15, SE = .06, p = .007) adjusting for race/ethnicity, income, education, parity, health behaviors, and chronic health conditions, though associations became nonsignificant when adjusted for body mass index.

CONCLUSIONS

In this low-income and ethnic/racially diverse sample of women, higher financial stress at 1-month postbirth predicted higher CRP. Study findings suggest that perceived financial stress stemming from socioeconomic disadvantage may be a particular deleterious form of stress affecting maternal biology during the year after the birth of a child.

Relationship of Psychosocial Resources With Allostatic Load: A Systematic Review

OBJECTIVE

Allostatic load (AL) represents cumulative wear-and-tear on the body and is operationalized as a multisystem index of biomarkers. Allostatic load is associated with morbidities and mortality, leading to a growing body of literature that uses AL as an outcome in its own right. Psychosocial resources (PSRs), such as mastery and social support, may influence health outcomes in part via AL, and the current review seeks to characterize the relations between PSRs and AL.

METHODS

A systematic review was conducted by searching PubMed, CINAHL Plus, PsycINFO, Scopus, and Embase for studies examining the relation between PSR(s) and AL in humans. From 1,417 abstracts screened, 60 full-text articles were reviewed, and 24 studies met inclusion criteria.

RESULTS

Mixed evidence exists for a relationship between PSRs and AL. Most (14/24) studies used a cross-sectional design, and only one study investigated whether a PSR predicted change in AL. Compared to cross-sectional studies, longitudinal studies were more likely to report a significant relationship (8/14 versus 8/10, respectively). Studies with statistically significant main or moderated effects had larger sample sizes than those reporting null effects. Whether a study reported a significant main or moderated relationship did not differ by whether psychological (8/11) or social (10/16) resources were assessed.

CONCLUSIONS

Evidence for a relationship between PSRs and AL is equivocal, and obtained significant relationships are generally small in magnitude. Gaps in the current literature and directions for future research are discussed. Longitudinal studies are needed that repeatedly assess PSRs and AL.

Meeting physical activity guidelines is associated with lower allostatic load and inflammation in Mexican Americans

Examine the relationship between physical activity (PA) and allostatic load in Mexican-Americans as well as variations by gender. Self-reported PA as well as cardiovascular, metabolic and inflammatory markers were assessed in 330 Mexican-American adults in the Cameron County Hispanic Cohort (Brownsville, TX, USA). Dependent variables included total allostatic load, blood pressure, metabolic, and inflammatory scores. PA participation was categorized as sedentary, low, moderate, high, and by whether activity was sufficient to meet public health guidelines. Logistic regression analyses were conducted using cross-sectional data, and tested interaction effects of gender and PA. High active participants had lower allostatic load and inflammatory risk than sedentary participants. These relationships held for meeting versus not meeting guidelines. Males meeting guidelines were less likely to have high inflammation than other groups. The data did not suggest a dose-response association. These findings indicate that PA may reduce accumulation of allostatic load, highlighting the importance of a physically active lifestyle across the life span.

Sociodemographic, behavioral and genetic determinants of allostatic load in a Swiss population-based study

Allostatic load (AL) is a marker of physiological dysregulation which reflects exposure to chronic stress. High AL has been related to poorer health outcomes including mortality. We examine here the association of socioeconomic and lifestyle factors with AL. Additionally, we investigate the extent to which AL is genetically determined. We included 803 participants (52% women, mean age 48±16years) from a population and family-based Swiss study. We computed an AL index aggregating 14 markers from cardiovascular, metabolic, lipidic, oxidative, hypothalamus-pituitary-adrenal and inflammatory homeostatic axes. Education and occupational position were used as indicators of socioeconomic status. Marital status, stress, alcohol intake, smoking, dietary patterns and physical activity were considered as lifestyle factors. Heritability of AL was estimated by maximum likelihood. Women with a low occupational position had higher AL (low vs. high OR=3.99, 95%CI [1.22;13.05]), while the opposite was observed for men (middle vs. high OR=0.48, 95%CI [0.23;0.99]). Education tended to be inversely associated with AL in both sexes(low vs. high OR=3.54, 95%CI [1.69;7.4]/OR=1.59, 95%CI [0.88;2.90] in women/men). Heavy drinking men as well as women abstaining from alcohol had higher AL than moderate drinkers. Physical activity was protective against AL while high salt intake was related to increased AL risk. The heritability of AL was estimated to be 29.5% ±7.9%. Our results suggest that generalized physiological dysregulation, as measured by AL, is determined by both environmental and genetic factors. The genetic contribution to AL remains modest when compared to the environmental component, which explains approximately 70% of the phenotypic variance.

Greater Leisure Time Physical Activity Is Associated with Lower Allostatic Load in White, Black, and Mexican American Midlife Women: Findings from the National Health and Nutrition Examination Survey, 1999 through 2004

BACKGROUND

Allostatic load is a useful construct to understand how social and environmental conditions get under the skin to affect health. To date, few studies have examined health-enhancing lifestyle behaviors and their potential benefits in reducing allostatic load. The purpose of this study was to investigate the contributions of leisure time physical activity on level of allostatic load among White, Black, and Mexican American midlife women.

METHODS

Data were from the National Health and Nutrition Examination Survey, 1999 through 2004 (n = 1,680, women ages 40-59). All analyses were weighted. Negative binomial regression was used to model a summative count measure of allostatic load (M = 2.30). Models were also computed to estimate adjusted predicted allostatic load for given levels of physical activity, and by race/ethnicity for each age category (40-44, 45-49, 50-54, 55-59), controlling for other demographics and medication use.

FINDINGS

Higher levels of physical activity were associated significantly with lower levels of allostatic load, independent of demographics. Compared with White women ages 40 to 44, all other racial/ethnic-by-age groups had significantly higher allostatic load. Higher socioeconomic status was associated with a lower allostatic load. Adjusted prediction models demonstrated associations between greater levels of physical activity and lower allostatic load for all ages and racial/ethnic groups.

CONCLUSIONS

Our findings suggest physical activity may ameliorate some of the effects of cumulative physiological dysregulation and subsequent disease burden in midlife women. Programs and policies that encourage and promote healthy aging and provide opportunities for a diversity of women to engage in health-enhancing lifestyle practices such as physical activity are recommended.

Work stress, caregiving, and allostatic load: prospective results from the Whitehall II cohort study

OBJECTIVES

Studies investigating health effects of work and family stress usually consider these factors in isolation. The present study investigated prospective interactive effects of job strain and informal caregiving on allostatic load (AL), a multisystem indicator of physiological dysregulation.

METHODS

Participants were 7007 British civil servants from the Whitehall II cohort study. Phase 3 (1991-1994) served as the baseline, and Phases 5 (1997-1999) and 7 (2002-2004) served as follow-ups. Job strain (high job demands combined with low control) and caregiving (providing care to aged or disabled relatives) were assessed at baseline. AL index (possible range, 0-9) was assessed at baseline and both follow-ups based on nine cardiovascular, metabolic, and immune biomarkers. Linear mixed-effect models were used to examine the association of job strain and caregiving with AL.

RESULTS

High caregiving burden (above the sample median weekly hours of providing care) predicted higher AL levels, with the effect strongest in those also reporting job strain (b = 0.36, 95% confidence interval = 0.01-0.71); however, the interaction between job strain and caregiving was not significant (p = .56). Regardless of job strain, participants with low caregiving burden (below sample median) had lower subsequent AL levels than did non-caregivers (b = -0.22, 95% confidence interval = -0.06--0.37).

CONCLUSIONS

The study provides some evidence for adverse effects of stress at work combined with family demands on physiological functioning. However, providing care to others may also have health protective effects if it does not involve excessive time commitment.

Source-specific social support and circulating inflammatory markers among white-collar employees

BACKGROUND

Despite known beneficial effects of social support on cardiovascular health, the pathway through which sources of support (supervisor, coworkers, family/friends) influence inflammatory markers is not completely understood.

PURPOSE

We investigated the independent and moderating associations between social support and inflammatory markers.

METHODS

A total of 137 male white-collar employees underwent a blood draw for measurement of high-sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), monocyte and leukocyte counts, and completed a questionnaire on social support.

RESULTS

Multivariable linear regression analyses controlling for covariates revealed that supervisor support was inversely associated with IL-6 (β = -0.24, p < 0.01) while coworker support was marginally associated with TNF-α (β = -0.16, p < 0.10). Support from family/friends was not associated with inflammatory markers.

CONCLUSION

Social support from the immediate supervisor may be a potential mechanism through which social support exerts beneficial effects on inflammatory markers in working men.

A systematic review of interventions to reduce stress in adolescence

Adolescence can be a stressful developmental phase, placing youth at risk for negative health outcomes. Evidence-based interventions are crucial to helping adolescents manage stress; yet, most of the literature on adolescent stress is observational and descriptive. We systematically reviewed the literature on stress management interventions for adolescents and found there is evidence to support the effectiveness of interventions that aim to develop cognitive skills among adolescents; however, most studies had small samples and relied on different operational definitions of outcomes. Few included biological indicators of stress. Further study is needed to develop interventions to enhance adolescents' capacity to manage stress.

Association of education and receiving social transfers with allostatic load in the Swiss population-based CoLaus study

BACKGROUND

Allostatic load reflects cumulative exposure to stressors throughout lifetime and has been associated with several adverse health outcomes. It is hypothesized that people with low socioeconomic status (SES) are exposed to higher chronic stress and have therefore greater levels of allostatic load.

OBJECTIVE

To assess the association of receiving social transfers and low education with allostatic load.

METHODS

We included 3589 participants (1812 women) aged over 35years and under retirement age from the population-based CoLaus study (Lausanne, Switzerland, 2003-2006). We computed an allostatic load index aggregating cardiovascular, metabolic, dyslipidemic and inflammatory markers. A novel index additionally including markers of oxidative stress was also examined.

RESULTS

Men with low vs. high SES were more likely to have higher levels of allostatic load (odds ratio (OR)=1.93/2.34 for social transfers/education, 95%CI from 1.45 to 4.17). The same patterns were observed among women. Associations persisted after controlling for health behaviors and marital status.

CONCLUSIONS

Low education and receiving social transfers independently and cumulatively predict high allostatic load and dysregulation of several homeostatic systems in a Swiss population-based study. Participants with low SES are at higher risk of oxidative stress, which may justify its inclusion as a separate component of allostatic load.

Allostatic load model associated with indoor environmental quality and sick building syndrome among office workers

This study investigates whether indoor environmental quality (IEQ) influences allostatic load (AL) and whether AL can be a predictor for sick building syndrome (SBS). We also assessed and compared the associations between AL and SBS versus 8-hydroxydeoxyguanosine (8-OHdG) and SBS. A total of 115 office workers from 21 offices completed self-reported SBS questionnaires, and provided 11 biomarkers for their AL. Multiple linear regressions and logistic regression analysis were applied to examine the correlations between IEQ and AL or 8-OHdG and between AL or 8-OHdG and SBS, respectively. Our data revealed that the neuroendocrine system was correlated with CO₂, the difference between indoor and outdoor CO₂ levels (dCO₂), and the indoor-outdoor ratio of CO₂ (CO₂ I/O). Metabolic system effects were associated with illumination. The relationships between illumination, CO₂, dCO₂, CO₂ I/O and 8-OHdG were consistent with those and AL in specific systems. Furthermore, we found that risks for SBS syndromes were related with neuroendocrine and metabolic system of the AL. 8-OHdG was associated with eye dryness or irritation, eye tiredness and vomiting. We conclude that IEQ significantly influences AL and that AL can be a predictor for reporting SBS with information on system-specific effects.

Does exposure to stressors predict changes in physiological dysregulation?

BACKGROUND

The allostatic load framework implies that cumulative exposure to stressors results in multi-system physiological dysregulation.

PURPOSE

The purpose of this study was to investigate the effect of stress burden on subsequent changes (2000-2006) in physiological dysregulation.

METHODS

Data came from a population-based cohort study in Taiwan (n = 521, aged 54+ in 2000, re-examined in 2006). Measures of stressful events and chronic strain were based on questions asked in 1996, 1999, and 2000. A measure of trauma was based on exposure to the 1999 earthquake. Dysregulation was based on 17 biomarkers (e.g., metabolic, inflammatory, neuroendocrine).

RESULTS

There were some small effects among men: chronic strain was associated with subsequent increases in dysregulation (standardized β = 0.08, 95 % CI = 0.01 to 0.20), particularly inflammation; life events were also associated with increased inflammation (β = 0.10, CI = 0.01 to 0.26). There were no significant effects in women.

CONCLUSIONS

We found weak evidence that stress burden is associated with changes in dysregulation.

Associations between nocturnal blood pressure dipping and the metabolic syndrome in high- vs. low-acculturated Mexican American women

BACKGROUND

Less nocturnal blood pressure (BP) dipping has been associated with greater odds for the metabolic syndrome (MetS), a constellation of risk factors associated with cardiovascular disease (CVD). Little work has examined this association in Hispanics, who have elevated rates of MetS, or investigated differences in this relationship by level of acculturation. The purpose of this study was to examine the association between BP dipping and MetS in Hispanic women and to determine if this association is moderated by acculturation status.

METHODS

Two hundred eighty-six Mexican American women underwent assessment of MetS components (BP, waist circumference, fasting glucose, high-density lipoprotein cholesterol, and triglycerides) and completed a 36-hour ambulatory BP monitoring protocol, during which systolic BP (SBP) and diastolic BP readings were obtained. Nocturnal BP dipping was calculated as the percentage difference between average daytime and nighttime BP. Acculturation was defined by the language (Spanish, English) in which participants preferred to complete study instruments.

RESULTS

Although no significant main effects for BP dipping or acculturation emerged for MetS, the SBP dipping by acculturation interaction was significantly related to MetS (P < 0.01). Simple slope analyses revealed that less SBP dipping related to greater odds of MetS in high-acculturated women, but SBP dipping and MetS were unrelated in low-acculturated women.

CONCLUSIONS

The strength of the association between BP dipping and CVD risk (as measured by MetS) appears to vary by acculturation in Hispanic women. Future studies should explore mechanisms behind the BP dipping and CVD risk association and relevant modifying factors.

Social and material adversity from adolescence to adulthood and allostatic load in middle-aged women and men: results from the Northern Swedish Cohort

Background

Little is known about the theoretically assumed association between adversity exposure over the life course and allostatic load in adulthood.

Purpose

This study aims to examine whether social and material adversity over the life course is related to allostatic load in mid-adulthood.

Methods

A 27-year prospective Swedish cohort (N = 822; 77% response rate) reported exposure to social and material adversities at age 16, 21, 30 and 43 years. At age 43, allostatic load was operationalized based on 12 biological parameters.

Results

Social adversity accumulated over the life course was related to allostatic load in both women and men, independently of cumulative socioeconomic disadvantage. Moreover, social adversity in adolescence (in women) and young adulthood (in men) was related to allostatic load, independently of cumulative socioeconomic disadvantage and also of later adversity exposure during adulthood.

Conclusion

Exposure to adversities involving relational threats impacts on allostatic load in adulthood and operates according to life course models of cumulative risk and a sensitive period around the transition into adulthood.

Electronic supplementary material

The online version of this article (doi:10.1007/s12160-011-9309-6) contains supplementary material, which is available to authorized users.

Diurnal patterns of salivary alpha-amylase and cortisol secretion in female adolescent tennis players after 16 weeks of training

We examined the effects of 16 weeks of training on diurnal pattern of salivary alpha-amylase (sAA), cortisol, and the ratio of sAA over cortisol (AOC) in 12 national adolescent female tennis players. Stress and recovery were also evaluated using the Recovery-Stress-Questionnaire for Athletes-RESTQ-Sport. Data were collected after a 2-week rest (January, W0), and 4 months after W0 (W16). Subjects collected five saliva samples throughout a day. While all participants displayed the previously shown decrease after awakening in adolescents at W0, they showed a rise in the alpha-amylase awakening response and a higher alpha-amylase activity output (p<0.01) at W16 compared to W0. For the daily rhythm of cortisol we found subjects having a low overall output of salivary cortisol (p<0.01) and a blunted response to awakening at W16. Furthermore, an increase in the ratio AOC at W16, and a negative correlation between this ratio and Sport-specific recovery score. Our findings offer support for the hypothesis that increase of training load during the study period induced asymmetry activation between the two stress systems, in relation to psychological alterations and performance decrease. These results provide encouragement to continue exploring the impact of training program using a psychobiological approach among young athletes in order to prevent fatigue and preserve the health of these athletes.