The heritability of perceived stress

BACKGROUND: Exploration of the degree to which perceived chronic stress is heritable is important as these self-reports have been linked to stress-related health outcomes. The aims of this study were to estimate whether perceived stress is a heritable condition and to assess whether heritability estimates vary between subjective stress reactivity and stress related to external demands. METHOD: A sample of 103 monozygotic and 77 dizygotic twin pairs completed three questionnaires designed to measure perceived stress: the Perceived Stress Scale (PSS), the Measure for the Assessment of Stress Susceptibility (MESA) and the Trier Inventory for the Assessment of Chronic Stress (TICS). The TICS assesses the frequency of stressful experiences on six scales, the MESA assesses subjective stress reactivity, and the PSS takes both factors into account. RESULTS: A multivariate model-fitting procedure revealed that a model with common additive genetic and shared environmental factors best fit the eight scales (PSS, MESA, six TICS scales). Heritabilities for the best-fitting model varied between 5% and 45%, depending on the scale. CONCLUSIONS: The present data suggest that perceived stress is in part heritable, that nearly half of the covariance between stress scales is due to genetic factors, and that heritability estimates vary considerably, depending on the questionnaire. Beyond methodological considerations that pertain to the validity of the questionnaires, these data suggest that studies assessing the heritability of perceived chronic stress should take the specific questionnaire focus into account.     

Effect of crude lipopolysaccharide from Escherichia coli O127:B8 on the amebocyte-producing organ of Biomphalaria glabrata (Mollusca)

Lipopolysaccharide (LPS) is a pathogen associated molecular pattern (PAMP) to which the internal defense system (IDS) of both vertebrates and invertebrates responds. We measured the mitotic response of the hematopoietic tissue of the schistosome-transmitting snail, Biomphalaria glabrata, to crude LPS from Escherichia coli 0127:B8. In a dose-response study, snails were injected with a range of concentrations of crude LPS, and mitotic figures were enumerated in histological sections of amebocyte-producing organ (APO) fixed at 24 h post-injection (PI) following a 6 h treatment with 0.1% colchicine. In APOs from Salvador strain snails, which are genetically resistant to infection with Schistosoma mansoni, LPS concentrations of 0.01 mg/ml and above triggered a large increase in mitotic activity, whereas in APOs from schistosome-susceptible NIH albino snails, concentrations of 0.1 mg/ml elicited a much smaller, but statistically significant increase. A time course study, without colchicine treatment, revealed that in Salvador APOs the mitotic response to 0.1 mg/ml occurred by 18 h PI, peaked at 24 h, and returned to control levels by 72 h; NIH albino APOs showed no detectible response. When Salvador APOs were exposed to crude LPS in vitro, no increase in mitotic activity occurred, a result suggesting the possible requirement for a peripheral tissue or hemolymph factor. The increased cell proliferation induced by crude LPS represents a novel systemic response of an invertebrate IDS to one or more PAMPs from a Gram-negative bacterium.     

Effects of perceived stress on pediatric chronic pain

The dearth of theoretically driven research on the predictors of pediatric chronic pain may unwittingly contribute to needless suffering in children and adolescents by underinvestigating a potentially treatable condition. The objective of the present study was to investigate the hypothesized predictive effects of perceived stress on pediatric chronic pain intensity in 148 children and adolescents. Consistent with thea priori Biobehavioral Model of Pediatric Pain, higher perceived stress was predictive of greater pediatric pain intensity. The results are discussed with regard to the implications for cognitive-behavioral pediatric pain treatment.     

Gender-specific association of perceived stress and inhibited breathing pattern

Stress can potentiate the development of hypertension via inhibition of renal excretory function. One potential mediating mechanism is an inhibited breathing pattern, because hypoventilation can decrease renal sodium excretion acutely via effects on pCO₂ and acid-base balance. Large individual differences in resting breathing patterns have beenwell-documented, with some individuals maintaining slow frequency and high pCO₂. Whether this breathing pattern is related to chronic stress has not been investigated. This study reports that high perceived stress over the past month was associated with significantly lower frequency breathing at rest, independently of age, race, or body mass index. This finding was more marked in women thaninmen. Inaddition, slow breathing frequency was independently associated with higher resting end tidal CO₂ in both men and women. This is the first known reportofan association of sustained stress with an inhibited breathing pattern in humans, and points to a pathway by which chronic stress might contribute to the development of hypertension, especially in women.     

The ultrastructure of the amebocyte-producing organ in Biomphalaria glabrata

The amebocyte-producing organ (APO) in normal and echinostome-sensitized Biomphalaria glabrata was studied at the ultrastructural level. The APO in unexposed snails consists of small clusters of primary ameboblasts resting on the epithelial cells lining the pericardium. The ameboblasts are held in a loose reticulum formed by extensions from smooth muscle and few fibroblastic cells. Secondary ameboblasts and amebocytes constitute further stages of this cell line. Amebocytes, resembling cells in the snail's circulation, appear in the blood sinus coursing through the interior of the APO. Exposure of snails to echinostome miracidia results in significant morphological changes in the organ. Large clusters of primary and and secondary ameboblasts appear, many of these cells undergoing mitosis. Fully activated APOs consist of masses of cells loosely arranged in zones of progressive maturation. Blood cells in activated APOs were significantly larger than those seen in normal APOs.     

High perceived stress in relation to life events is associated with blunted cardiac reactivity

The current study examined whether the perception of life stress related to cardiovascular reactivity. Participants (n = 100) completed the Perceived Stress Scale, the Undergraduate Stress Questionnaire, and undertook a standard mental arithmetic stress task. Blood pressure and pulse rate were measured at baseline, during, and following stress task exposure. Reactivity was the difference between stress and baseline cardiovascular activity. A perceived stress difference score (PSDS) was calculated by subtracting the Undergraduate Stress Questionnaire scores from the Perceived Stress Scale scores. Two groups were created: high PSDS (n = 15; PSDS at least 1 SD above the mean) and low PSDS (n = 15; PSDS at least 1 SD below the mean). There was a significant difference between groups in pulse rate reactivity, F(1,28) = 8.73, p = .006, η² = .24. High PSDS scores were associated with significantly lower pulse rate reactions to stress. Those who perceived their lives as more stressful than their actual stress exposures justified would appear to be characterised by blunted cardiac reactivity.     

The impact of perceived stress and perceived control on anxiety and mood disorders in noncardiac chest pain

Chest pain without detectable heart disease, noncardiac chest pain (NCCP), is linked with anxiety and depression. Theory posits stress and perceived control may relate to NCCP. We hypothesized stress would have direct and mediated effects via perceived control on anxiety and mood disorders in NCCP. Patients (N = 113) completed questionnaires and a structured diagnostic interview. Stress and perceived control were associated with anxiety and mood disorder severity. Perceived control fully mediated the relation between stress and mood disorder severity but not anxiety disorder severity. Results are partially supportive of anxiety-based theories of NCCP.     

Burnout, perceived stress, and cortisol responses to awakening

OBJECTIVE: The effects of burnout and perceived stress on early morning free cortisol levels after awakening were investigated in a group of teachers. Previous studies revealed that cortisol levels show a significant increase after awakening, with high intraindividual stability. METHODS: Sixty-six teachers from local public schools (42 women and 24 men, mean age 42+/-5 years) were asked to sample saliva for cortisol analysis on 3 consecutive days. On each day, cortisol levels were measured at the time of awakening and 15, 30, and 60 minutes thereafter. On the night before the third day, subjects took 0.5 mg dexamethasone orally for testing glucocorticoid feedback inhibition. Burnout and perceived stress were measured by three different questionnaires. RESULTS: Perceived stress correlated with increases of cortisol levels during the first hour after awakening after dexamethasone pretreatment. In addition, teachers scoring high on burnout showed lower overall cortisol secretion on all sampling days, and a higher suppression of cortisol secretion after dexamethasone administration. In the subgroup of teachers with both high levels of perceived stress and high levels of burnout, a lower overall cortisol secretion was observed on the first 2 days, with stronger increases during the first hour after awakening after dexamethasone suppression. This subgroup also showed the lowest self-esteem, the highest external locus of control, and the highest number of somatic complaints. CONCLUSIONS: These results demonstrate differential effects of burnout and perceived stress on hypothalamic-pituitary-adrenal axis regulation.     

Association between perceived racism and physiological stress indices in Native Hawaiians

The association between racism and the physical health of native U.S. populations has yet to be examined despite their high risk for stress-related disorders and a history of discrimination toward them. We examined the correlation between perceived racism and the two physiological stress indices of cortisol level and blood pressure in 146 adult Native Hawaiians. Attributed and felt racism were assessed with a 10-item shortened version of the Oppression Questionnaire. Height, weight, blood pressure, and salivary cortisol samples (AM and PM) were collected and analyzed along with information on Hawaiian ancestry, BMI, age, sex, marital status, education level, general psychological stress, and ethnic identity. The results indicated that Native Hawaiians reporting more attributed racism had significantly (P < .05) lower average cortisol levels than those reporting less attributed racism, after adjusting for socio-demographic, biological, and psychosocial confounders. Native Hawaiians reporting more felt racism had a significantly higher systolic blood pressure than those reporting less, but this association was not significant after adjusting for the aforementioned confounders. Racism appears to be a chronic stressor that can “get under the skin” of Native Hawaiians by affecting their physical health and risk for stress-related diseases, possibly, through mechanisms of cortisol dysregulation.     

Sleep characteristics,sources of perceived stress and coping strategies in adolescent athletes

The aim of the study was to examine sleep characteristics, scheduling of activities, perceived stress and coping strategies between periods of perceived high and low scheduling commitments in adolescent athletes. Twenty adolescents (10 male and 10 female) wore an Actiwatch during two 14‐day testing periods, one in in January (JAN), which was deemed to be a period of low school and sport commitments, and one in March (MAR), during which there was a high volume of school and sport commitments. Actiwatches and sleep diaries assessed sleep quantity and quality, a daily schedule of all activities in 30‐min increments was recorded and questionnaires related to perceived stress and coping strategies were administered. Time in bed and asleep, latency, efficiency and number of awakenings were not different between JAN and MAR (p > 0.05). Sleep durations were lower than their age‐related recommendations (JAN 449 ± 47 min versus MAR 437 ± 31 min). Examination of differences between sexes showed shorter latency and higher sleep efficiency in female participants compared with male participants. Participants spent more time at school, completing homework, and travelling to and competing in sport, with reduced time spent on resting, social activities, physical activity and meal times during MAR compared with JAN (p < 0.05). Finally, stress levels were significantly increased during MAR compared with JAN, with no difference between sexes (p < 0.05). Adolescent athletes not attaining sufficient sleep quantity or quality during periods of low and high school and sport commitments, are experiencing increased perceived stress during these busy times but are using a wider range of coping strategies during this time.     

Consequences of boundary-spanning demands and resources for work-to-family conflict and perceived stress

Using work-family border theory, this article examines relationships between boundary-spanning demands and resources and work-to-family conflict and perceived stress. The analysis uses data from 2,109 respondents from the 2002 National Study of the Changing Workforce. The demands that were positively related to work-to-family conflict and perceived stress were commuting time, bringing work home, job contacts at home, and work-family multitasking. Work-family multitasking partially explained the effects of bringing work home and job contacts at home on conflict and stress. For resources, time off for family responsibilities and a supportive work-family culture showed negative associations with conflict and stress. Work-to-family conflict partially mediated relationships between several demands and resources and perceived stress.     

Emotional intelligence and perceived stress in healthcare students: a multi-institutional, multi-professional survey

Background  

Emotional intelligence (EI) is increasingly discussed as having a potential role in medicine, nursing, and other healthcare disciplines, both for personal mental health and professional practice. Stress has been identified as being high for students in healthcare courses. This study investigated whether EI and stress differed among students in four health professions (dental, nursing, graduate mental health workers, medical) and whether there was evidence that EI might serve as a buffer for stress.     

Depressed mood but not fatigue mediate the relationship between physical activity and perceived stress in middle-aged women

Objective

To determine whether depressed mood and fatigue mediate the relationships between physical activity, body mass index, menopausal hot flashes, and perceived stress.

Method

This study is a secondary analysis of data obtained from a sub-sample of peri- and postmenopausal women (N = 212) from the TREMIN Research Program on Women's Health.

Results

The hypothesized mediational model was tested using path analysis within a structural equation modeling framework in Mplus Version 5.1. In unadjusted analysis, the relationships between physical activity, menopausal hot flashes, and perceived stress were mediated by depressed mood; fatigue mediated the relationships between hot flashes, body mass index, and perceived stress. When adjusting for age, insomnia, menopausal and hormone use status, the mediational effects of depressed mood on stress remained significant only for physical activity, and fatigue mediated the relationship between hot flashes and stress. The adjusted model explained 70% of variance in perceived stress, 82% of variance in depressed mood, and 81% of variance in fatigue.

Conclusion

Depressed mood may partially explain the relationship between physical activity and perceived stress in middle-aged women, however further studies are needed to corroborate causality.     

Are body perceptions and perceived appearance judgments by others linked to stress and depressive symptoms?

Body dissatisfaction has consistently been linked to depressive symptoms. We posit stress as a pathway, with differential links to two aspects of body esteem, including body dissatisfaction and evaluations attributed to others about one's body and appearance. The Trier Social Stress Test was administered, and cortisol responses to acute psychosocial stress and survey data (perceived chronic stress, self-reported body esteem, and depressive symptoms) were assessed in 57 undergraduates (28F). Chronic stress mediated the association between body image and depressive symptoms. These findings support stress as a pathway by which poor self-image gets “under the skin” to negatively affect health.     

Heart rate variability, trait anxiety, and perceived stress among physically fit men and women.

BACKGROUND: It is unclear from prior reports whether the relationships between self-ratings of anxiety or emotional stress and parasympathetic nervous system components of heart rate variability are independent of personality and cardiorespiratory fitness. We examined those relationships in a clinical setting prior to a standardized exercise test. METHODS AND RESULTS: Heart rate variability (HRV) was measured during 5 min of supine rest among 92 healthy men (N=52) and women (N=40) who had above-average cardiorespiratory fitness as indicated by peak oxygen uptake measured during grade-incremented treadmill exercise. HRV datasets were decomposed into low-frequency (LF; 0.05-0.15 Hz) and high-frequency (HF; 0.15-0.5 Hz) components using spectral analysis. Self-ratings of trait anxiety and perceived emotional stress during the past week were also assessed. CONCLUSIONS: There was an inverse relationship between perceived emotional stress during the past week and the normalized HF component of HRV (P=0.038). This indicates a lower cardiac vagal component of HRV among men and women who perceived more stress. That relationship was independent of age, gender, trait anxiety, and cardiorespiratory fitness. It was also independent of heart rate; mean arterial blood pressure; and respiration rate, factors which can influence HRV and might be elevated among people reporting anxiety and perceived stress. We conclude that vagal modulation of heart period appears to be sensitive to the recent experience of persistent emotional stress, regardless of a person's level of physical fitness and disposition toward experiencing anxiety.     

Impact of acculturation on depression,perceived stress and self-esteem in young Middle Eastern American adults

Background: Human biologists have a longstanding interest in understanding the biological and health impacts of migration. Acculturation, the cultural adjustment that a group or individual experiences when previously separate cultures interact, has been found to be one pathway through which migration may impact human biology and health, not only for the migrants themselves, but also their descendants.

Aim: The authors conducted a pilot study to examine the relationship between acculturation and perceived stress, self-esteem and depression among young Middle-Eastern American adults.

Subject and methods: Survey data were collected from 48 young Middle-Eastern American adults. Participants were divided into one of two acculturation categories, integrated (American and Middle Eastern culture oriented) and assimilated (American culture oriented). Health measures were compared between these acculturation categories.

Results: Integrated individuals had significantly lower stress (F?=?8.1, p?<?0.01) and depression (F?=?10.8, p?<?0.01) than assimilated individuals. Integrated individuals had lower self-esteem than assimilated individuals (F?=?5.0, p?<?0.05). Generational status, a proxy used for acculturation, was only significantly associated with self-esteem (F?=?3.15, p?=?0.05).

Conclusion: This pilot study furthers understanding of the effects acculturation can have on perceived stress and mental health among young Middle-Eastern Americans. Future research should incorporate biological measures of stress to determine the physiological impacts of acculturation.     

Association between human brucellosis and adverse pregnancy outcome: a cross-sectional population-based study

To investigate the association between the incidence of human brucellosis (HB) and adverse pregnancy outcomes (APOs), a population-based, cross-sectional aggregate data study was conducted in Israel between 2010 and 2014. HB-endemic localities were matched by ethnicity, population size and socioeconomic status to localities with a low incidence of HB. We compared APO rates in high-incidence vs low-incidence localities. The primary outcome was intrauterine fetal demise (IUFD). Secondary outcomes were premature birth (less than 37 weeks), early or threatened labour and poor fetal growth. APOs are expressed as events per 1,000 live or dead births. Eleven high-incidence localities, all Arab villages or cities, were matched to 11 low-incidence localities. Localities were well-matched with regard to the matching criteria, fertility indices, health insurance access and education, but were imbalanced geographically. All defined APOs occurred significantly more frequently in the high-incidence localities. The associations translated to an absolute increase of 3.6 cases of IUFD (95% CI 1.6–5.3), 11.7 preterm births (4.8–18.3), 6.6 cases of early or threatened labour (2.2–10.9) and 7 cases of poor fetal growth (3–10.8), per 10,000 live or dead births. Owing to a geographic imbalance between high- and low-incidence localities, we conducted an analysis restricted to Southern localities of Arab Bedouins showing a significant association between yearly HB incidence and IUFD incidence, odds ratio 1.05 (1.03–1.06). HB incidence is epidemiologically linked to serious pregnancy complications. Early detection of infection through active surveillance during pregnancy followed by appropriate treatment should be evaluated as additional public heath strategy in endemic settings.     

Angiogenic markers could predict adverse pregnancy outcomes

Clinical and Experimental Medicine - Adverse pregnancy outcomes (APOs) have been a devastating actuality in clinic. However, the pre-onset risk factors, that correlated with pregnancy failure,...     

Age and perceived stress independently influence daily blood pressure levels and variation among women employed in wage jobs

The purpose of this study was to examine whether age and perceived stress were independent factors affecting blood pressure variation associated with changing daily microenvironments among women employed outside the home. The subjects of this study were 91 women from the same workplace (age 33.8 ± 8.5 years; range 18.2–49.3 years) who wore an ambulatory blood pressure monitor over the course of one workday. Blood pressure averages were calculated at work (11 am to 3 pm), home (6 pm to approximately 10 pm), and during sleep (approximately 10 pm to 6 am). The stressfulness of the work and home microenvironments was rated by self‐report on a scale of 0 (low) to 10 (high). A repeated measures analysis of covariance was used to assess the cross‐classified effects of perceived stress (work stressed [work > home stress; N = 41], home stressed [home > work stress; N = 39], and equally stressed [work = home stress; N = 11]) and age group (18.0–29.9 years, N = 31; 30–39.9 years, N = 34; 40–49.9 years, N = 26) on the blood pressure averages with daily environment as a within‐subject factor and measures of body fat and menstrual phase as covariates. Work‐stressed women had higher systolic blood pressure at work, home, and during sleep than home‐stressed women (127 vs 119, P < 0.001; 124 vs 119, P < 0.05, and 111 vs 104, P < 0.005). There were similar patterns for diastolic blood pressure. Age showed a U‐shaped relationship, with women in the 30–39.9 year age range generally having lower systolic and diastolic blood pressures at work (P < 0.05), home (P < 0.10), and during sleep (P < 0.05) than younger and older age groups. The interaction between age group and perceived stress level was not significant, so that the variation in blood pressure associated with perceived stress (work stressed, home stressed, and equally stressed) was similar in each age group. Although blood pressure changes with age, environment‐related stress, particularly job‐related stress, continues to have a significant effect on daily blood pressure variation. However, data also indicate that blood pressure measured during the day may not necessarily show a linear increase with age. Am. J. Hum. Biol. 13:268–274, 2001. © 2001 Wiley‐Liss, Inc.     

Anti-domain 1 of beta2-glycoprotein I aids risk stratification in lupus anticoagulant-positive patients

Clinical and Experimental Medicine - Lupus anticoagulant (LA) is considered a risk factor for thromboembolism (TE) and adverse pregnancy outcomes (APOs). However, quite a few patients diagnosed...