Work-related psychosocial factors and carotid atherosclerosis

Adrenal SGLT1 or SGLT2 as predictors of atherosclerosis under chronic stress based on a computer algorithm

Background

Chronic stress promotes the development of atherosclerosis, causing disruptions in the body's hormone levels and changes in the structural function of organs.

Objective

The purpose of this study was to investigate the pathological changes in the adrenal gland in a model of atherosclerosis under chronic stress and to verify the expression levels of Sodium-glucose cotransporter (SGLT) 1 and SGLT2 in the adrenal gland and their significance in the changes of adrenal gland.

Methods

The model mice were constructed by chronic unpredictable stress, high-fat diet, and Apoe-/- knockout, and they were tested behaviorally at 0, 4, 8 and 12 weeks. The state of the abdominal artery was examined by ultrasound, and the pathological changes of the aorta and adrenal glands were observed by histological methods, and the expression levels and distribution of SGLT1 and SGLT2 in the adrenal gland were observed and analyzed by immunofluorescence and immunohistochemistry. The predictive value of SGLT1 and SGLT2 expression levels on intima-media thickness, internal diameter and adrenal abnormalities were verified by receiver operating characteristic (ROC) curves, support vector machine (SVM) and back-propagation (BP) neural network.

Results

The results showed that chronic stress mice had elevated expression levels of SGLT1 and SGLT2. The model mice developed thickening intima-media and smaller internal diameter in the aorta, and edema, reticular fiber rupture, increased adrenal glycogen content in the adrenal glands. More importantly, analysis of ROC, SVM and BP showed that SGLT1 and SGLT2 expression levels in the adrenal glands could predict the above changes in the aorta and were also sensitive and specific predictors of adrenal abnormalities.

Conclusion

SGLT1 and SGLT2 could be potential biomarkers of adrenal injury in atherosclerosis under chronic stress.

Psychosocial job conditions and biomarkers of cardiovascular disease: A cross-sectional study in the Swedish CArdioPulmonary bioImage Study (SCAPIS)

AIMS

The aim of this study was to investigate associations between psychosocial work exposure and the presence of biological and imaging biomarkers of cardiovascular disease.

METHODS

This cross-sectional study was conducted in a sub-cohort of the Swedish CArdioPulmonary bioImage Study (SCAPIS). Psychosocial exposure was evaluated with the job demand-control model, and analysed according to the standard categorization: high strain, active, passive and low strain (reference). Biomarkers (blood pressure, high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, coronary artery calcification (CAC) and metabolic syndrome) were measured, or derived through measurements, from clinical examinations. Gender-specific prevalence ratios (PRs) and 95% confidence intervals (CIs) were calculated with regression models and adjusted for age, education, smoking, physical activity, general life stress and body mass index (BMI).

RESULTS

The analyses included 3882 participants (52.5% women). High strain (high demands-low control) was linked to increased PR for low HDL cholesterol in women, adjusted for all covariates (PR 1.76; 95% CI 1.25-2.48). High strain was also related to moderately increased PR for metabolic syndrome in men, after adjustments for all covariates except BMI (PR 1.25; 95% CI 1.02-1.52). In addition, passive work (low demands-low control) was associated with diastolic hypertension in women (fully adjusted: PR 1.29; 95% CI 1.05-1.59). All relationships between psychosocial factors and LDL cholesterol or CAC (both genders), or hypertension (men), were non-significant.

CONCLUSIONS

Poor psychosocial job conditions was associated with the presence of low HDL cholesterol and diastolic hypertension in women, and metabolic syndrome in men. These findings contribute to the knowledge of potential pathways between stressful work and coronary heart disease.

Job Stress and Subclinical Cardiovascular Disease: Cross-Sectional Results of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

OBJECTIVE

We aimed to evaluate the relationship between job stress and subclinical cardiovascular disease at ELSA-Brasil.

METHODS

We considered job stress domains (demand, skill discretion, decision authority, and social support) as independent variables and coronary artery calcium (CAC more than 0) and carotid intima-media thickness (CIMT more than P75% as a continuous variable) as dependent ones. Odds ratio (OR) and 95% confidence interval (95% CI) were presented crude, with further adjustments for sociodemographic, cardiovascular risk factors, and lifestyle variables. Linear regression models were built for CIMT using the same covariates.

RESULTS

Although significant associations were observed in the crude models, after multivariate adjustment CAC and CIMT were not significantly associated with demand, skill discretion, decision authority, and social support.

CONCLUSIONS

Our results did not support an association between job stress and subclinical cardiovascular disease measured by CAC or CIMT.

Long working hours and cardiovascular mortality: a census-based cohort study

OBJECTIVES

Long working hours have been associated with cardiovascular disease (CVD) mortality. However, results are inconsistent and large cohort studies are needed to confirm these findings.

METHODS

We conducted a census-based cohort study including 11,903,540 Italian workers aged 20-64 years, registered in the 2011 census, with a 5-year follow-up (2012-2016). We estimated cause-specific hazard ratios (cHRs) through Cox regression models to quantify the association between long working hours and CVD mortality.

RESULTS

Over 5 years of follow-up, 17,206 individuals died from CVD (15,262 men and 1944 women). Men working 55 or more hours per week had a cHR of 0.95 (95% confidence interval, CI 0.89-1.02) for all CVDs, while women showed a cHR of 1.19 (95% CI 0.95-1.49). Professional women working more than 55 h per week had a cHR of 1.98 (95% CI 0.87-4.52).

CONCLUSIONS

This study does not support an association between long working hours and CVD mortality among active Italian men, while it suggests a possible excess risk among women, although based on limited number of events.

Post-trauma cardiovascular risk factors and subclinical atherosclerosis in young adults following the war in Bosnia and Herzegovina

Background: Risk of cardiovascular disease (CVD) has been associated with stress from serving in a war, but it has not been established whether children who experience war-related stress are at increased CVD risk. Objective: This study aimed to compare CVD risk factors in young adults according to whether they experienced traumatic events as children during the 1990-1995 war in Bosnia and Herzegovina, and whether those exposed to trauma have evidence of subclinical atherosclerosis. Method: We examined 372 first-year medical students who were preschool children during the war (1990-1995) (average age 19.5 ± 1.7 years, 67% female) in 2007-2010. They completed the Semi-Structured Interview for Survivors of War. CVD risk factors and carotid intima-media thickness (CIMT) measurements were obtained and compared in individuals with and without trauma. We also examined whether increased CIMT was independently associated with trauma after adjustment for other risk factors. Results: From multiple logistic regression, only elevated triglycerides (> 1.7 mmol/l) were associated with a 5.2 greater odds of having experienced trauma. The mean CIMT of subjects with trauma was greater than that of non-trauma-exposed subjects (0.53 mm vs 0.50 mm, p = 0.07). Moreover, trauma was independently associated with higher CIMT (difference = 0.036 mm, p = 0.024) after adjustment for CVD risk factors. Conclusions: We show that most CVD risk factors are associated with post-war trauma in young adults, and, if present, such trauma is associated with higher triglycerides and higher levels of CIMT in multivariable analysis.

Associations between Job Strain and Arterial Stiffness: A Large Survey among Enterprise Employees from Thailand

As an intermediate endpoint to cardiovascular disease, arterial stiffness has received much attention recently. So far, the research on work stress and arterial stiffness is still sparse and inconsistent, and no investigations on work stress and cardiovascular health among the Thai working population have been reported. Therefore, we conducted an epidemiological study among 2141 Thai enterprise employees (858 men and 1283 women) who were free from any diagnosed cardiovascular disease. Work stress was measured using Karasek’s Job Demand–Control model for job strain (a combination of high demand and low control). Arterial stiffness was evaluated by a non-invasive approach using pulse-wave analysis based on a finger photoplethysmogram. Multivariable linear regression was applied to examine associations between job strain and arterial stiffness. In men, job strain was significantly associated with arterial stiffness (β  =  0.078, 95% confidence interval  =  0.026 to 0.130), after accounting for sociodemographic, behavioral, dietary and biomedical factors. However, the association in women was not significant. As the first study in Thailand on work stress and cardiovascular risk, we found that job strain might be an important risk factor for cardiovascular disease among Thai working men. Further studies with longitudinal design are warranted.

A genetic risk score for CAD, psychological stress, and their interaction as predictors of CAD, fatal MI, non-fatal MI and cardiovascular death

Background

Psychological stress is an independent risk factor for cardiovascular disease (CVD), but the mechanism by which stress is associated with CVD is not entirely understood. Although genetic factors are implied in both stress responsivity and cardiovascular reactivity, no studies to date have investigated their interactions with stress for cardiovascular end points. The objective was to elucidate the association and interactions between a genetic risk score (GRS), individual genetic variants and stress for three cardiovascular end points: coronary artery disease (CAD), fatal myocardial infarction (MI), non-fatal MI, and cardiovascular death.

Methods and findings

18,559 participants from the Malmö Diet Cancer Study, a population-based prospective study, were included in the analyses. Cox proportional hazards regression models were used and adjusted for a large number of known predictors of cardiovascular end points. Mean follow-up time in years was 14.6 (CAD; n = 1938), 14.8 (fatal MI; n = 436), 14.8 (non-fatal MI; n = 1108), and 15.1 (cardiovascular death; n = 1071) respectively. GRS was significantly associated with increased risks of CAD (top quartile hazard ratio [HR], 1.72; 95% confidence interval [CI], 1.51–1.96), fatal MI (top quartile HR, 1.62; 95%CI, 1.23–2.15), non-fatal MI (top quartile HR, 1.55; 95%CI, 1.31–1.84), and cardiovascular death (top quartile HR, 1.29; 95%CI, 1.08–1.53). Stress was not independently associated with any end point and did not interact with GRS. Four individual genetic variants interacted unfavorably with stress for end points with mortality outcomes.

Conclusion

A GRS composed of 50 SNPs and predictive of CAD was found for the first time to also strongly predict fatal MI, non-fatal MI and cardiovascular death. A stress-sensitive component of the GRS was isolated on the basis of individual genetic variants that interacted unfavorably with stress.

Psychological stress and risk of incident atrial fibrillation in men and women with known atrial fibrillation genetic risk scores

Psychological stress has been reported as a possible trigger of atrial fibrillation (AF). No studies have investigated whether any association between stress and AF could be modified by genetic susceptibility to AF (AF-genetic risk score (AF-GRS)). 8765 men and 13,543 women from the Malmö Diet Cancer Study, a population-based cohort, were included in the analyses. A variable representing stress was constructed from questions measuring job strain, and from one question assessing non-occupational stress. Cox proportional hazards regression models were adjusted for known covariates of AF. Mean follow-up times and number of recorded incident AF were 14.2 years and 1116 events for men, and 15.1 years and 932 events for women. Among women, high stress was associated with AF in the age adjusted model (hazard ratio [HR], 1.22; 95% confidence interval [CI], 1.01-1.47) but not following multivariable adjustment (HR, 1.15; 95% CI, 0.95-1.39). Stress was not associated with incident AF in men. AF-GRS was significantly associated with incident AF for both genders. Stress did not interact significantly with genetic susceptibility to AF in men or women. Chronic stress is not associated with long-term incident hospital diagnosed AF. This association does not appear to be modified by genetic susceptibility to AF.

Ultrasound-detected carotid plaque as a predictor of cardiovascular events

Ultrasound detection of carotid plaque can be performed with equipment that is available in many clinical settings and can identify patients at increased risk of cardiovascular (CV) disease. We reviewed the literature to determine the CV risk factors associated with the presence of carotid plaque and whether its presence is associated with the presence and extent of coronary artery disease. A MEDLINE search subsequently was performed to determine whether carotid plaque burden predicts future CV events. Studies that had more than 300 subjects and reported hazard ratios or relative risk estimates for CV events, or data from which these values could be calculated, were included. References from identified studies also were examined for inclusion in the review. Nine studies met these criteria. Although there was not a uniform definition of carotid plaque, eight studies found that the presence of carotid plaque predicted incident CV death and/or myocardial infarction. In several studies, this relationship persisted after adjustments for risk factors. Ultrasound detection of carotid plaque is a straightforward, inexpensive, and safe tool that has the potential to be used in an office setting to help clarify a patient’s CV risk.

Associations of Psychological Well-Being With Carotid Intima Media Thickness in African American and White Middle-Aged Women

OBJECTIVES

The present cross-sectional study aimed to a) examine associations between measures of psychological well-being, specifically life satisfaction and life engagement, and intima media thickness, a subclinical marker of atherosclerosis; b) investigate if the interaction of psychological well-being and life events correlated with intima media thickness; and c) explore these relationships across race.

METHODS

A sample of 485 women (38% African American and 62% white; mean [standard deviation] age = 50.2 [2.9] years) underwent ultrasonography to assess carotid artery intima media thickness (IMT). The women completed self-report measures of life satisfaction, life engagement, and life events.

RESULTS

Average (standard deviation) IMT was 0.666 (0.10) mm. Life satisfaction showed a significant, independent, inverse relationship with IMT, after controlling for demographic, behavioral, psychological, and cardiovascular covariates (β = -0.105, p = .039), such that each 1-point higher life satisfaction score was correlated with a significant 0.008-mm lower level of mean IMT. No significant association was seen between life events and IMT (r = 0.05, p = .32), and life satisfaction did not interact with life events on IMT (β = -0.036, p = .46). No significant interaction between life satisfaction and race on IMT was observed (β = 0.068, p = .37). In contrast to life satisfaction, life engagement was not a significant correlate of IMT (r = -0.07, p = .12).

CONCLUSIONS

Life satisfaction, a measure of psychological well-being, is an important independent correlate of subclinical atherosclerosis in middle-aged women.

Causes of changes in carotid intima-media thickness: a literature review

Atherosclerosis causes significant morbidity and mortality. Carotid intima-media thickness (CIMT) predicts future cardiovascular and ischaemic stroke incidence. CIMT, a measure of atherosclerotic disease, can be reliably determined in vivo by carotid ultrasound. In this review, we determined that CIMT is associated with traditional cardiovascular risk factors such as age, sex, race, smoking, alcohol consumption, habitual endurance exercise, blood pressure, dyslipidemia, dietary patterns, risk-lowering drug therapy, glycemia, hyperuricemia, obesity-related anthropometric parameters, obesity and obesity-related diseases. We also found that CIMT is associated with novel risk factors, including heredity, certain genotypic indices, anthropometric cardiovascular parameters, rheumatoid arthritis, immunological diseases, inflammatory cytokines, lipid peroxidation, anthropometric hemocyte parameters, infectious diseases, vitamin D, matrix metalloproteinases, and other novel factors and diseases. However, the conclusions are inconsonant; the underlying causes of these associations remain to be further explored.

Work Stress as a Risk Factor for Cardiovascular Disease

The role of psychosocial work stress as a risk factor for chronic disease has been the subject of considerable debate. Many researchers argue in support of a causal connection while others remain skeptical and have argued that the effect on specific health conditions is either negligible or confounded. This review of evidence from over 600,000 men and women from 27 cohort studies in Europe, the USA and Japan suggests that work stressors, such as job strain and long working hours, are associated with a moderately elevated risk of incident coronary heart disease and stroke. The excess risk for exposed individuals is 10-40 % compared with those free of such stressors. Differences between men and women, younger versus older employees and workers from different socioeconomic backgrounds appear to be small, indicating that the association is robust. Meta-analyses of a wider range of health outcomes show additionally an association between work stress and type 2 diabetes, though not with common cancers or chronic obstructive pulmonary disease, suggesting outcome specificity. Few studies have addressed whether mitigation of work stressors would reduce the risk of cardiovascular disease. In view of the limited interventional evidence on benefits, harms and cost-effectiveness, definitive recommendations have not been made (e.g. by the US Preventive Services Taskforce) for the primary prevention of cardiovascular disease via workplace stress reduction. Nevertheless, governments are already launching healthy workplace campaigns, and preventing excessive work stress is a legal obligation in several countries. Promoting awareness of the link between stress and health among both employers and workers is an important component of workplace health promotion.

Posttraumatic stress disorder, combat exposure, and carotid intima-media thickness in male twins

Posttraumatic stress disorder (PTSD) is associated with an increased risk of ischemic heart disease, though the pathophysiologic mechanisms remain unclear. Carotid artery intima-media thickness (CIMT) is a measure of subclinical atherosclerosis. We examined whether PTSD and combat exposure were associated with CIMT in Vietnam War-era twins after controlling for shared genetic and childhood factors. Between 2002 and 2010, we studied 465 middle-aged twins from the Vietnam Era Twin Registry who were free from cardiovascular disease. PTSD was diagnosed using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and CIMT was measured by ultrasound. Mixed-effects regression models were used to examine individual, between-pair, and within-pair associations. Approximately 13% of participants met the criteria for PTSD, and 45% served in the Vietnam Theater. PTSD was associated with 32.7 μm higher CIMT (95% confidence interval (CI): 0.9, 64.5) after adjustment for confounders. The average CIMT for the pair increased by 59.7 μm for each additional twin with PTSD (95% CI: 15.9, 104.2). We found no significant within-pair differences in CIMT when comparing PTSD-discordant co-twins. Results for combat exposure were similar, but its association with CIMT weakened after adjustment for PTSD (95% CI: 7.0, 45.3). Among Vietnam War-era veterans, combat exposure and PTSD are associated with CIMT, though the associations are largely mediated by shared childhood factors.

[Demand-Control model and occupational stress among nursing professionals: integrative review]

The Demand Control model aims to evaluate the occupational stress. This study aimed to know, through an integrative review of the literature, the scientific production about the Demand Control Model to investigation occupational stress among nursing professionals from 2000 to 2011.Of the 16 selected studies, five were published in 2009. Of these studies, 56.25% assessed the Demand and Control dimensions and their correlations with workers' health problems; 37.5% of these studies were related with mental health. The results showed a lack of national publications. We recommend that authors conduct experimental studies to reduce the occupational stress for better conditions of workers' mental health.

Occupational stress and subclinical atherosclerosis: a systematic review

BACKGROUND

Stress is a common hazard in the work environment and is associated with multiple adverse health effects. The association between work-related stress (WRS) and cardiovascular disease has been established in a number of epidemiological studies.

METHODS

A systematic review was conducted according to the PRISMA statement of the English literature involving WRS and carotid artery intima media thickness (CIMT).

RESULTS

Four cohorts and six cross-sectional studies of occupational stress and CIMT were identified. All cohorts and five of the cross-sectional studies reported a significant positive association, while one reported an inverse association of WRS and CIMT.

DISCUSSION

The weight of the evidence that we were able to identify suggests that occupational stress results in an increased risk of atherosclerosis, assessed via CIMT. Studies that include longitudinal measures of stress and intermediate cardiac endpoints, with adequate accounting for confounders, are needed. Interventional studies should also be conducted to determine whether CIMT progression can be prevented with workplace stress reduction.

Stress and cardiovascular disease: an update on current knowledge

Considerable progress has been made during the past decade in research on cardiovascular effects of stress. Early-life stressors, such as childhood abuse and early socioeconomic adversity, are linked to increased cardiovascular morbidity in adulthood. Our updated meta-analyses of prospective studies published until 2011 show a 1.5-fold (95% confidence interval 1.2-1.9) increased risk of coronary heart disease among adults experiencing social isolation and a 1.3-fold (1.2-1.5) excess risk for workplace stress; adverse metabolic changes are one of the underlying plausible mechanisms. Stress, anger, and depressed mood can act as acute triggers of major cardiac events; the pooled relative risk of acute coronary syndrome onset being preceded by stress is 2.5 (1.8-3.5) in case-crossover studies. Stress is also implicated in the prognosis of cardiovascular disease and in the development of stress (takotsubo) cardiomyopathy. A major challenge over the next decade is to incorporate stress processes into the mainstream of cardiovascular pathophysiological research and understanding.

Daily psychological demands are associated with 6-year progression of carotid artery atherosclerosis: the Pittsburgh Healthy Heart Project

OBJECTIVE

We examine associations between the perception of ongoing psychological demands by ecological momentary assessment (EMA) and 6-year changes in carotid artery atherosclerosis by ultrasonography.

METHODS

A total of 270 initially healthy participants collected ambulatory blood pressure (ABP) and recorded their daily experiences, using electronic diaries, during two 3-day periods. Mean intima-media thickness (IMT) and plaque were assessed in the carotid arteries using B-mode ultrasound at baseline and again during a 6-year follow-up (mean follow-up duration = 73 months).

RESULTS

Among those who had no exposure to antihypertensive medications during the course of follow-up (n = 192), daily psychological demands were associated with greater progression of IMT as well as plaque, after adjusting for demographic and risk factor covariates. Associations between demands and plaque change were partially accounted for by ABP differences among those reporting high demands. Among those who were employed at baseline (n = 117), 6-year IMT changes were more strongly associated with ratings of daily demands than with traditional measures of occupational stress.

CONCLUSIONS

These data support the role of psychological demands as a correlate of subclinical atherosclerotic progression, they point to ABP as a potential mechanism facilitating these effects, and they highlight the utility of EMA measures for capturing daily psychological demands with potential effects on health.

Stress and cardiovascular disease

The physiological reaction to psychological stress, involving the hypothalamic-pituitary-adrenocortical and sympatho-adrenomedullary axes, is well characterized, but its link to cardiovascular disease risk is not well understood. Epidemiological data show that chronic stress predicts the occurrence of coronary heart disease (CHD). Employees who experience work-related stress and individuals who are socially isolated or lonely have an increased risk of a first CHD event. In addition, short-term emotional stress can act as a trigger of cardiac events among individuals with advanced atherosclerosis. A stress-specific coronary syndrome, known as transient left ventricular apical ballooning cardiomyopathy or stress (Takotsubo) cardiomyopathy, also exists. Among patients with CHD, acute psychological stress has been shown to induce transient myocardial ischemia and long-term stress can increase the risk of recurrent CHD events and mortality. Applications of the 'stress concept' (the understanding of stress as a risk factor and the use of stress management) in the clinical settings have been relatively limited, although the importance of stress management is highlighted in European guidelines for cardiovascular disease prevention.

Relationship between chronic stress and carotid intima-media thickness (IMT) in elderly Alzheimer's disease caregivers

The stress associated with providing care for a spouse diagnosed with Alzheimer's disease can have adverse effects on cardiovascular health. One potential explanation is that chronic caregiving stress may contribute to the development of atherosclerosis. The purpose of this study was to determine whether the duration that one has provided care is associated with the degree of atherosclerotic burden, as measured by carotid artery intima-media thickness (IMT). One hundred and ten Alzheimer caregivers [mean age 74 ± 8 (SD) years, 69% female] underwent in-home assessment of carotid artery IMT via B-mode ultrasonography. Data regarding medical history, blood pressure, and multiple indicators of caregiving stress were also collected. Multiple regression indicated that duration of care was positively associated with IMT measured in the internal/bifurcation segments of the carotid artery (β = 0.202, p = 0.044) independent of risk factors such as age, gender, body mass index, smoking history, sleep quality, hypertension status, and caregiving stressors. Duration of care was positively associated with IMT in the common carotid artery, but the relationship was not significant. These findings provide more evidence of the link between chronic caregiving stress and cardiovascular disease and indicate that enduring the experience of caregiving over a period of years might be associated with atherosclerotic burden.

Metabolic syndrome and carotid intima media thickness in urban police officers

OBJECTIVE

To examine the association between metabolic syndrome (MetSyn) and carotid intima media thickness (IMT) separately in male and female police officers.

METHODS

MetSyn was defined using 2005 guidelines. B-mode ultrasound was used to measure mean and maximum (12 and 36 segments) carotid artery thickness. Analysis of covariance was used to compare mean IMT values across individuals categorized by number of MetSyn components. Adjustments were made for age, smoking status, and low-density lipoprotein cholesterol.

RESULTS

Among 106 women, the adjusted mean common and maximum36 carotid IMT were significantly and positively associated with number of MetSyn components. No associations were found in men (n = 304). Adjusted carotid IMT values were inversely associated with low high-density lipoprotein cholesterol and directly with hypertension in women.

CONCLUSIONS

Number of MetSyn components was significantly associated with carotid IMT in female but not in male officers.

Associations of occupation, job control and job demands with intima-media thickness: the Multi-Ethnic Study of Atherosclerosis (MESA)

OBJECTIVES

Occupation has been linked to cardiovascular disease (CVD) incidence and mortality, but few studies have investigated occupation in relation to early atherosclerotic disease. This study examined associations between various occupational characteristics and carotid artery intima-media thickness (IMT) in a multi-ethnic sample.

METHODS

The Multi-Ethnic Study of Atherosclerosis (MESA) recruited 6814 adults aged 45-84 years and free of clinical CVD (response rate 60%, 51% female). Questionnaire data were used to determine occupational group (managerial/professional, sales/office, service, blue-collar), psychosocial job characteristics (ie, job demands, job control) and other sociodemographic information.

RESULTS

Common carotid artery (CCA)-IMT was greater for blue-collar jobs than for management/professional jobs (mean difference = 0.012 mm, p = 0.049) after adjustment for age, sex, race, place of birth (US or foreign born) and CVD risk factors. Compared to management/professional jobs, internal carotid artery (ICA)-IMT was greater for sales/office, service and blue-collar jobs (mean difference = 0.071 mm, p < 0.001; 0.057 mm, p = 0.009; and 0.110 mm, p < 0.001, respectively) after adjustment for age, sex, race and place of birth. The difference between blue-collar jobs and management/professional jobs remained significant after additional adjustment for CVD risk factors, income and education (mean difference = 0.048 mm, p = 0.045). Higher levels of control at work were associated with thinner CCA-IMT (mean difference = -0.009 mm, p = 0.016, adjusted for age, sex, race and place of birth) but not with ICA-IMT. Job demands had no significant association with IMT.

CONCLUSIONS

Blue-collar jobs and low levels of job control were associated with the development of subclinical atherosclerosis.

Carotid plaque in absence of traditional and non-traditional cardiovascular risk factors

Carotid plaque is a marker of subclinical atherosclerosis that predicts the presence of coronary artery disease and cardiovascular events. The patient complained of chest discomfort accompanied by ECG abnormalities. Treadmill test demonstrated horizontal ST segment depression, however, coronary angiography did not show any significant stenosis. Carotid plaque was detected by carotid ultrasonogram, despite of the absence of any traditional and non-traditional cardiovascular risk factors, especially normal lipid profiles. This case suggests that unknown determinants of carotid atherosclerosis that we cannot elucidate from the history, physical examination, and common laboratory tests may play a role in the development of carotid plaque.

Associations of job strain and occupation with subclinical atherosclerosis: The CARDIA Study

PURPOSE

Although occupational factors have been associated with symptomatic ischemic heart disease, associations between job strain (low decision latitude and high psychological demands) and risk for subclinical atherosclerosis measured by coronary artery calcium (CAC) have not been assessed.

METHODS

CAC was measured in 3695 participants in the Coronary Artery Risk Development in Young Adults study in 2000 to 2001 and 2005 to 2006. Job characteristics measured by the demand-control model (psychological demands and decision latitude) were assessed in 1987 to 1988 and in 1995 to 1996. Associations between non-zero CAC and previous job characteristics and occupation were assessed, adjusting for potential covariates.

RESULTS

Low decision latitude, high psychological demands, and job strain at either earlier examination were not associated with a positive CAC, nor were changes in the status of these job characteristics between 1987/1988 and 1995/1996. However, participants whose jobs were classified as managerial or professional in 1995/1996 were less likely to have a positive CAC than those in laborer occupations.

CONCLUSIONS

Job strain measured at two earlier time points was not related to the presence of CAC at follow-up 5 to 18 years later. The association between earlier occupation and CAC may reflect socioeconomic differences or other occupational, industrial, or labor market characteristics.

The association between effort-reward imbalance and coronary atherosclerosis in a Chinese sample

BACKGROUND

Previous studies of job strain and coronary heart disease (CHD) have produced mixed findings. We aimed to examine the association between job stress evaluated by the effort-reward imbalance (ERI) model and coronary atherosclerosis assessed by coronary angiography in a Chinese sample.

METHODS

Three-hundred twenty participants accepting coronary angiography for the first time were enrolled in series. Job stressors were evaluated by the ERI model. The presence and severity of CHD were assessed by measuring the coronary artery stenosis (the presence of >50% luminal stenosis in one or more major coronary arteries). The association between job stressors and CHD was examined by multivariate analysis.

RESULTS

Compared with the low-level group, high-level effort, overcommitment, and ERI increased CHD risk with odds ratio (OR) 2.5 (95% confidence interval (CI): 1.2-5.0), 2.5 (95% CI: 1.2-5.0), 2.4 (95% CI: 1.2-4.9), respectively, after adjustment for confounders. They were also significantly positively correlated with the complexity of coronary artery lesions, respectively. Dose-response relationships were observed.

CONCLUSIONS

ERI was associated with coronary artery lesions in a sample of Chinese workers. Longitudinal research and interventional designs are needed to confirm the mechanism and to provide evidence for the prevention of CHD.

Psychosocial working conditions and exhaustion in a working population sample of Swedish middle-aged men and women

BACKGROUND

Exhaustion is a concept of interest for both occupational health research and stress-disease theory research. The aim of the present study was to explore associations between chronic stressors, in terms of psychosocial working conditions, and exhaustion in a Swedish middle-aged population sample.

METHODS

A vocationally active population sample of the Malmö Shoulder and Neck Study cohort, comprising 2555 men and 2466 women between 45 and 64 years of age, was used. Psychosocial working conditions, assessed by means of the demand-control-support model, were measured longitudinally with a 1-year interval. Exhaustion was assessed by the SF-36 vitality scale and measured at follow-up, yielding a cross-sectional study design.

RESULTS

Exhaustion was twice as common in women as in men. High psychological job demands, low job control and low job support were independently associated with exhaustion in both men and women. These associations remained after controlling for a variety of potential confounders and mediators, including socio-demographic factors, lifestyle factors, musculoskeletal pain, disease, other work-related factors (including physical workload) and non-work-related factors. High demands in combination with low control (job strain), and job strain combined with low job support (iso-strain), increased the risk for exhaustion.

CONCLUSION

Psychosocial working conditions seem to contribute to exhaustion in middle-aged men and women. Future research should include exploration of exhaustion as a possible mediator between work stress and disease, as well as exploration of other chronic stressors, including non-work-related stressors, regarding their effects on exhaustion in men and women.

Relationship between job strain and radial arterial wave reflection in middle-aged male workers

OBJECTIVE

This study examined the relationship between job stain and radial arterial wave reflection as expressed by the augmentation index (AI), a marker of cardiovascular risk, in middle-aged male workers.

METHODS

Radial AI was measured using automated applanation tonometry in 808 working men (mean age; 47+/-5 years) at a company in Kanagawa, Japan in 2007. An elevated AI represents the deterioration of arterial properties and increased cardiovascular risk. Job demand and job control (decision latitude) were evaluated by a self-administered, Brief Job Stress Questionnaire. High job strain was defined as the combination of high job demand and low job control.

RESULTS

In the entire study population, the mean+/-SD and the median of AI were 74+/-13% and 75%, respectively. High job strain was seen in 267 subjects. In a multiple logistic regression analysis with adjustment for multiple potential confounders, high job strain showed a significantly increased odds ratio (1.47, 95% CI; 1.04-2.09, P=0.029) for an elevated AI (> or =75%).

CONCLUSION

High job strain was significantly associated with an elevated radial AI. The measurement of AI may be useful when incorporated in workplace interventions to reduce the risk of cardiovascular disease, especially at sites where workers tend to perceive high job strain.

Relationship between two alternative occupational stress models and arterial stiffness: a cross-sectional study among Japanese workers

OBJECTIVE

Numerous studies have reported the relationships between job characteristics and coronary heart diseases. However, there are only a few reports on the association between occupational stresses and arterial stiffness as a marker of early stage arthrosclerosis. The aim of this study was to clarify the relationship between occupational stress models--Siegrist's effort reward imbalance and Karasek's demand control model (DCM)--and arterial stiffness using brachial-ankle pulse-wave velocity (baPWV).

METHODS

The participants were local government employees (3,412 men and 854 women) aged 35 and over who had their annual health checkups. The associations between occupational stress questionnaires of the two theoretical models and a risk of increased arterial stiffness using baPWV were examined.

RESULTS

On performing multiple linear regression analysis after fully adjusting the model, high strain, which was defined as a combination of both low job control and high job demands in the DCM, was found to be significantly associated with a high risk of arterial stiffness (P = 0.027) in women. However, in men, although low job control was positively significant with a high value of baPWV adjusted for each step, modest but not significant association was found after adjustment for all covariates.

CONCLUSION

In conclusion, the present study indicates that high strain indicated by high demands and low control is associated with increased arterial stiffness in women. The types of job stress associated with a high risk of arterial stiffness may differ by gender.

The relation of exposure to shift work with atherosclerosis and myocardial infarction in a general population

OBJECTIVES

We tested the hypothesis that working shifts is related to atherosclerosis and myocardial infarction.

BACKGROUND

The number of shift workers is continuously increasing. Shift work is discussed to be related with cardiovascular heart disease.

METHODS

A total of 2510 subjects recruited for the population-based Study of Health in Pomerania were tested, 698 of whom were former shift workers. A general population sample was examined to reach generalizibility and to produce results independent from the effects of the personal shift schedule and from the specific working conditions. Carotid ultrasound was performed to evaluate carotid intima-media thickness. We used multivariable analyses to estimate the coronary heart disease risk, adjusted for age, sex and atherosclerotic risk factors, stratified by exposure to shift work and its duration.

RESULTS

Atherosclerotic risk factors differed in part between shift workers and non-shift workers. Shift work was associated with atherosclerosis and myocardial infarction, depending on the duration of the exposure and the age of the participants. Multivariable Cox regression analysis identified shift work as a risk factor for myocardial infarction to be manifest at younger ages (adjusted hazard ratio 1.53, 95% CI 1.06-2.22).

CONCLUSIONS

Exposure to shift work is a risk factor for atherosclerosis and myocardial infarction. Special prevention programs for shift workers should be provided.

Perceived work-related stress and early atherosclerotic changes in healthy employees

OBJECTIVE

This study was conducted to investigate the relationship between perceived work-related stress and preclinical atherosclerosis.

METHODS

A total of 100 managers and 50 office workers aged 35-65 participated in a questionnaire study. Individual, family and work-related stress risk factors and coping were evaluated in all the studied individuals. Serum levels of biochemical (total cholesterol, LDL, HDL, TG, glucose) and serological risk factors of atherosclerosis (anticardiolipin, anti-beta(2) GPI, anti-oxLDL, anti-HSP and anti-hsCRP antibodies) were evaluated. A computer analysis of B-mode ultrasound images was used to assess carotid artery intima-media thickness (IMT) and atherosclerotic plaque in carotid arteries. Statistical analysis was conducted with SPSS v. 11.5.

RESULTS

The studied individuals showed average ranges of both the global stress level and of coping results. In 71% no changes were found in the ultrasound image and in 29% of individuals (43) the presence of plaque was shown. The mean value of the IMT measure was 0.0618 +/- 0.013 mm. IMT and plaque correlated negatively with the level of global work-related stress (r = -0.26; P < 0.01; and r = -0.28; P < 0.01; respectively). No correlation was found either between work-related stress and coping, or between coping and IMT (P > 0.05), or between work-related stress and healthy lifestyle (no smoking, no excessive use of alcohol, high physical activity), or between healthy lifestyle and IMT (P > 0.05). Positive correlation between IMT and LDL and smoking did not result from higher stress reaction in the studied individuals.

CONCLUSIONS

The explanation of the negative correlation between perceived work-related stress and preclinical atherosclerosis was not confirmed either by the subjects under high stress undertaking healthy protective activities or by their escaping into unhealthy behaviour. The most probable interpretation of the results is that in individuals with a low level of perceived work-related stress, somatization of stress takes place.

Job strain in men, but not in women, predicts a significant rise in blood pressure after 6.5 years of follow-up

BACKGROUND

Job strain (high demands and low decision latitude) has been associated with hypertension and cardiovascular disease, especially in men. Most studies on job strain and hypertension have been cross-sectional, and prospective data are inconsistent.

OBJECTIVE

To prospectively describe the effects of different psychosocial work characteristics on office blood pressure changes.

METHODS

In total, 448 men and women, mean age 55 years, were followed for a mean of 6.5 years. At baseline, work characteristics and cardiovascular risk factors were assessed. Only employed subjects aged 63 years or younger were eligible for participation.

RESULTS

Men with baseline job strain had a significantly greater increase in both systolic blood pressure (7.7 mmHg, P = 0.02), and diastolic blood pressure (5.6 mmHg, P = 0.003), compared to the group with low work demands and high decision latitude ('relaxed'). These findings were significant also after adjustments for age, follow-up time, baseline blood pressure, blood pressure treatment at baseline and follow-up, and length of education. Work demands were more strongly correlated with blood pressure increase than decision latitude. For women, no significant associations between psychosocial work characteristics and blood pressure changes were found, apart from a weak trend of association between increasing decision latitude and increasing blood pressure.

CONCLUSION

Job strain significantly predicts an increase in office blood pressure in middle-aged men, but not in women. Work demands were more strongly correlated with blood pressure increase than decision latitude in men.

Psychosocial factors at home and at work and four-year progression in intima media thickness

This study analyzed the relationship between psychosocial factors and progression in intima media thickness (IMT). In 1998 and 2002, 95 healthy participants underwent a clinical examination, including ultrasound of the arteria carotis communis (ACC). IMT progression in women was 0.033 mm/year (SD=0.033) and in men 0.048 mm/year (SD=0.033). For cohabiting women as opposed to single women, the means for total IMT progression over the 4 years were, respectively, 0.137 (SE=0.019) and 0.016 (SE=0.048) mm. For women with above average as opposed to below average mean scores of effort, IMT progression were 0.149 (SE=0.026) and 0.098 (SE=0.024) mm, respectively. For men without children as opposed to men with children, mean scores for IMT progression were 0.231 (SE=0.029) and 0.137 (SE=0.028) mm, respectively. For men above average as opposed to those below average, scores of effort-reward imbalance IMT progression were 0.216 (SE=0.030) and 0.155 (SE=0.027) mm, respectively. Adjustment for confounders did not change the results significantly. We found that psychosocial factors were independent significant predictors of IMT progression. The associations were different between the genders.

Early risk factors, job strain, and atherosclerosis among men in their 30s: the Cardiovascular Risk in Young Finns Study

We examined whether preemployment influences confounded the association between job strain and atherosclerosis. We assessed biological, familial, and socioeconomic risk factors of coronary heart disease at 12 to 18 years of age and job strain and carotid artery intima-media thickness at 33 to 39 years of age for a cohort of 358 men. Adolescent risk factors predicted adult intima-media thickness but had little effect on the dose-response relation between greater job strain and greater intima-media thickness. Pre-employment influences did not confound the association between job strain and atherosclerosis.

Why is evidence on job strain and coronary heart disease mixed? An illustration of measurement challenges in the Whitehall II study

OBJECTIVE

Evidence regarding the status of job strain as a risk factor for coronary heart disease (CHD) is mixed, including both results supporting the risk status and null findings. However, previous studies have typically assessed job strain at one point in time only. We examined whether the failure of such measurement to reflect long-term job strain could contribute to false null findings.

METHODS

Job strain and its components, as stress indicators, were assessed twice (3-year time lag) for 5043 men and 2210 women who were free of apparent CHD at baseline. Incident CHD after the stress measurement comprised CHD death, a first nonfatal myocardial infarction, or definite angina (mean follow-up, 10.4 years). The data analysis was based on Cox proportional-hazard models adjusted for age, sex, and employment grade and corrected using regression dilution ratios calculated from short-term repeat data in a random subsample.

RESULTS

In the total cohort, incidence of new CHD was higher for higher levels of job strain and demands. For these stress indicators, the corrected excess CHD risk was 30% and 29% higher than the corresponding uncorrected estimates, whereas the corresponding increase for job control was only 13%. Effects of job strain and work demands, but not job control, were stronger for a subgroup, with consistent exposure measurements over time than for the total cohort.

CONCLUSION

This evidence suggests that use of single-time exposure measures may underestimate the status of long-term job strain as a CHD risk factor.

Job strain and early atherosclerosis: the Cardiovascular Risk in Young Finns study

OBJECTIVE

The purpose of this study was to determine whether job strain and social support are associated with early atherosclerosis measured by carotid intima-media thickness (IMT) in young adults.

METHODS

The subjects were 478 men and 542 women (mean age 32.3) who were participating in the ongoing prospective Cardiovascular Risk in Young Finns study. Job strain was defined as a joint effect of job demands and job control. Early atherosclerosis was determined with IMT ultrasound. The associations between job strain, social support, and IMT were evaluated using multiple linear regressions.

RESULTS

In men, job strain was associated with increased IMT after adjustment for age. This association was not attenuated by additional adjustment for established risk factors of coronary heart disease. In women, job strain was not associated with IMT. No 3-way interaction of job demand, job control, and social support on IMT was found.

CONCLUSION

These findings suggest that job strain may be related to atherosclerosis already in its early nonsymptomatic stages in men.

Relation between psychological strain and carotid atherosclerosis in a general population

OBJECTIVE

To investigate the hypothesis that psychological strain is related to carotid atherosclerosis in a large general population sample.

METHODS

Intima-media thickness and the prevalence of atherosclerotic plaques in the carotid arteries were quantitatively assessed by high resolution ultrasound among 2164 participants (1112 women and 1052 men, aged 45 to 75 years) of the SHIP (study of health in Pomerania), an epidemiological survey of a random sample of the population of north eastern Germany. Psychological strain was measured by 13 items reflecting typical psychological complaints. Each item was graded by the study participants on a four point scale (from 0, absent, to 3, severe) and a psychological strain score was generated by summing these 13 items.

RESULTS

Mean psychological strain score was 10.8 (7.0) (median score 10) among women and 8.5 (6.2) (median score 8) among men. Psychological strain did not predict carotid intima-media thickness among either men or women. However, after adjustment for covariates, high psychological strain and carotid plaques were independently and linearly related, with plaque prevalence odds of 1.03 (95% confidence interval (CI) 1.01 to 1.05, p = 0.009) per increment of the psychological strain score among women and 1.04 (95% CI 1.01 to 1.07, p = 0.003) among men.

CONCLUSIONS

This study identified a relation between general psychological strain and carotid atherosclerosis.

Psychosocial factors in the development of coronary artery disease

The fact that traditional risk factors only account for approximately two thirds of cases of coronary artery disease (CAD) has stimulated increasing interest in the relationship between CAD and psychosocial factors. Five areas--chronic stress, socioeconomic status (SES), personality, depression, and social support--have been most thoroughly examined. There is evidence to support a causal relationship between chronic stress, SES, depression, and social support and development of CAD. In this article, we discuss the epidemiologic evidence linking psychosocial factors and CAD, and review the effects of psychosocial factors on several pathophysiologic mechanisms that have been proposed as potential mediators of CAD. The hypothalamic-pituitary-adrenal axis, hypertension and cardiovascular reactivity, endothelial function, inflammatory markers, platelets, coagulation factors, fibrinogen, lipids, glucose metabolism, and lifestyle factors have all been implicated in this process. Recently, the first intervention trials have been carried out, although with initially disappointing results. Reducing the cardiovascular risk due to these psychosocial factors will be one of the major health care challenges in the future.

Job Strain or Healthy Work: A Question of Task Design

Objectively evaluated task requirements were used to classify jobs causing high strain, low strain, and jobs conducive to personal development. Effects of these job characteristics on psychophysiological outcomes were tested in 241 employees by using 24-hr ambulatory assessment of blood pressure (BP), heart rate, and mood. Self-reports about job characteristics showed that employees working in jobs conducive to personal development perceived the highest job demands and decision latitude. They also showed a healthy cardiovascular behavior with increased diastolic BP at work and its strong unwinding at night. Although self-reports about job characteristics did not differ between low- and high-strain jobs, employees exposed to high-strain jobs had higher systolic and diastolic BP during work and more often a disturbed relaxation ability.