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

Associations of effort-reward imbalance at work and quality of life among workers after stroke: a one-year longitudinal study in Thailand

Stroke incidence is increasing among working-age population, but the role of psychosocial stress in the workplace in predicting quality of life (QoL) after stroke onset is understudied. This longitudinal study aimed to investigate the relationship between work stress, measured by the effort-reward imbalance (ERI) model, and QoL over one-year period among 103 Thai workers who had experienced a stroke. The study evaluated the effort (E)-reward (R) ratio and over-commitment, the extrinsic and intrinsic components of the ERI model, before discharge; QoL was repeatedly measured at baseline, six months, and 12 months after discharge, respectively, using the Short Form Version 2 (SF-12v2) indicators of physical and mental health composite scores. Generalized estimating equations were used to examine longitudinal relationships between work stress at baseline and QoL over one year by testing the hypotheses that E-R ratio and over-commitment would have direct effects on QoL, and potential moderating effects of over-commitment on E-R ratio and QoL. The results supported the ERI model partially, as over-commitment was significantly associated with poor mental health (coefficient - 8.50; 95% CI: -13.79, -3.20) after adjusting baseline sociodemographic, behavioral, and clinical characteristics, while the E-R ratio was not significantly associated with physical or mental health; the interaction between the E-R ratio and over-commitment was also not significant. These findings suggest that more attention should be paid to workers' personal coping skills and ability to handle work-related problems and prioritize interventions that address over-commitment to promote long-term mental health among workers with stroke.

Association between psychosocial work-related factors at midlife and arterial stiffness at older age in a prospective cohort of 1736 white-collar workers

OBJECTIVE

Arterial stiffness and exposure to psychosocial work-related factors increase the risk of developing cardiovascular disease. However, little is known about the relationship between psychosocial work-related factors and arterial stiffness. We aimed to examine this relationship.

DESIGN

Prospective cohort study.

SETTING

Public organisations in Quebec City, Canada.

PARTICIPANTS

The study included 1736 white-collar workers (women 52%) from 19 public organisations.

PRIMARY AND SECONDARY OUTCOME MEASURES

Association between psychosocial work-related factors from the job strain and effort-reward imbalance (ERI) models assessed at study baseline (1999-2001) with validated instruments and arterial stiffness assessed using carotid-femoral pulse wave velocity at follow-up, on average 16 years later (2015-2018). Generalised estimating equations were used to estimate differences in arterial stiffness between exposed and unexposed participants. Subgroup analyses according to sex, age, blood pressure (BP), cardiovascular risk score and employment status were conducted.

RESULTS

Among participants with high diastolic BP (≥90 mm Hg) at baseline, aged 47 on average, those exposed to high job strain had higher arterial stiffness (1.38 m/s (95% CI: 0.57 to 2.19)) at follow-up, 16 years later, following adjustment for a large set of potential confounders. The trend was similar in participants with high systolic BP (≥140 mm Hg) exposed to high job strain (0.84 m/s (95% CI: -0.35 to 2.03)). No association was observed for ERI in the total sample and counterintuitive associations were observed in subgroup analyses.

CONCLUSIONS

Job strain may have a long-term deleterious effect on arterial stiffness in people with high BP. Interventions at midlife to reduce job strain may mitigate arterial stiffness progression.

Identification of the susceptible subpopulations for wide pulse pressure under long-term exposure to ambient particulate matters

Wide pulse pressure (WPP) is a preclinical indicator for arterial stiffness and cardiovascular diseases. Long-term exposure to ambient particulate matters (PMs) would increase the risk of WPP. Although reducing pollutants emissions and avoiding outdoor activity during a polluted period are effective ways to blunt the adverse effects. Identifying and protecting the susceptible subpopulation is another crucial way to reduce the disease burdens. Therefore, we aimed to identify the susceptible subpopulations of WPP under long-term exposure to PMs. The WPP was defined as pulse pressure over 60 mmHg. Three-year averages of PMs were estimated using random forest approaches. Associations between WPP and PMs exposure were estimated using generalized propensity score weighted logistic regressions. Demographic, socioeconomic characteristics, health-related behaviors, and hematological biomarkers were collected to detect the modification effects on the WPP-PMs associations. Susceptible subpopulations were defined as those with significantly higher risks of WPP under PMs exposures. The PMs-WPP associations were significant with ORs (95%CI) of 1.126 (1.094, 1.159) for PM₁, 1.174 (1.140, 1.210) for PM_2.5, and 1.111 (1.088, 1.135) for PM₁₀. There were 17 subpopulations more sensitive to WPP under long-term exposure to PMs. The susceptibility was higher in subpopulations with high BMI (Q3-Q4 quartiles), high-intensive physical activity (Q3 or Q4 quartile), insufficient or excessive fruit intake (Q1 or Q5 quartile), insufficient or too long sleep length (<7 or >8 h). Subpopulations with elevated inflammation markers (WBC, LYM, BAS, EOS: Q3-Q4 quartiles) and glucose metabolism indicators (HbA1c, GLU: Q3-Q4 quartiles) were more susceptible. Besides, elder, urban living, low socioeconomic level, and excessive red meat and sodium salt intake were also related to higher susceptibility. Our findings on the susceptibility characteristics would help to develop more targeted disease prevention and therapy strategies. Health resources can be allocated more effectively by putting more consideration to subpopulations with higher susceptibility.

Sex-dependent correlates of arterial stiffness in Tanzanian adults

OBJECTIVE

Arterial stiffness is a known indicator for cardiovascular disease. However, the factors that lead to arterial stiffening have primarily been studied in participants from high-income countries. Here, we examine clinical and lifestyle metrics in relation to arterial stiffness in Tanzanian adults.

METHODS

We performed pulse wave velocity (PWV), the gold standard measure of arterial stiffness, on 808 Tanzanian adults (ages 18-65) enrolled in a longitudinal cohort studying trends in blood pressure.

RESULTS

As expected, PWV was strongly associated with age, blood pressure and sex. We controlled for these factors in our statistical analysis. Lifestyle metrics were compared across multiple PWV quantiles. We found that determinants of PWV varied by sex: in female participants, PWV was associated with common obesity metrics and menopause, while in male participants, PWV was associated with HIV status and duration of anti-retroviral therapy (ART). Further clinical and lifestyle factors such as marriage status and type of occupation were also significantly associated with PWV and moderated by sex.

CONCLUSION

Together, our data demonstrate the importance of studying sex-specific causal pathways for arterial stiffness and of including under-represented populations in these studies.

Acute mental stress-caused arterial stiffening can be counteracted by brief aerobic exercise

PURPOSE

Acute mental stress (MS) causes an elevation in pulse wave velocity (PWV), an index of arterial stiffness. In contrast, aerobic exercise acutely decreases arterial stiffness, even in the short term. The present study aimed to examine whether acute MS-caused arterial stiffening can be counteracted by brief aerobic exercise.

METHODS

Thirteen young healthy men (mean age, 20 ± 1 years) participated in two randomized experimental visits where they were subjected to acute MS followed by seated rest (RE) or cycling exercise (EX) trials. Following a 5-min MS task, the participants in the RE trial rested on a chair for 10 min (from 10 to 20 min after the cessation of the task), whereas those in the EX trial cycled at 35% of heart rate reserve for the same duration. Heart-brachial PWV (hbPWV), brachial-ankle PWV (baPWV), heart-ankle PWV (haPWV), and the cardio-ankle vascular index (CAVI) were simultaneously measured at baseline and 5, 30, and 45 min after the task.

RESULTS

Both trials caused significant elevations (P < 0.05) in hbPWV, haPWV, and CAVI at 5 min after the task; subsequently, this persisted until 45 min after the task in the RE trial, whereas the elevations in the EX trial were eliminated. In the RE trial, baPWV significantly increased (P < 0.05) at 30 and 45 min after the task, whereas such an increase was not observed in the EX trial.

CONCLUSION

The findings of the present study reveal that brief aerobic exercise counteracts arterial stiffening caused by acute MS.

Serum leptin levels are positively associated with aortic stiffness in patients with chronic kidney disease stage 3-5

Leptin potentially exerts atherogenic effects.This study evaluated the relationship between serum leptin levels and aortic stiffness in patients with stage 3-5 chronic kidney disease (CKD). Totally 205 participants were enrolled. Fasting blood sample were checked and serum leptin were measured by enzyme immunoassay. Aortic stiffness was measured as the carotid-femoral pulse wave velocity (cfPWV). 73 (35.6%) of 205 patients showed cfPWV >10 m/s were defined as aortic stiffness group. Compared with the remaining patients, the aortic stiffness group had high prevalence of diabetes mellitus, older age, higher waist circumference, body fat mass, systolic blood pressure, fasting glucose, and higher serum leptin level. In multivariable logistic regression analysis the independent predictors of cfPWV >10 m/s included leptin levels (odds ratio [OR]: 1.061, 95% confidence interval [CI]: 1.027-1.095, P < 0.001), age (OR: 1.064, 95% CI: 1.033-1.096, P< 0.001), and systolic blood pressure (OR: 1.021, 95% CI: 1.006-1.037, P = 0.006). Multivariable forward stepwise linear regression analysisshowed a positive association between log-transformed leptin levels and log-cfPWV (β = 0.192, adjusted R² change = 0.042, P = 0.001). Thus, aortic stiffness is positively correlated with serum leptin levels in patients with stage 3-5 CKD.Abbreviations: BUN, blood urea nitrogen; cfPWV, carotid-femoral pulse wave velocity; CI, confidence interval; CKD, chronic kidney disease; Cre, creatinine; DBP, diastolic blood pressure; DM, diabetes mellitus; eGFR, estimated glomerular filtration rate; LDL-C, low-density lipoprotein cholesterol; OR, odds ratio; SBP, systolic blood pressure; TCH, total cholesterol; TG, triglycerides.

Impact of acute mental stress on segmental arterial stiffness

PURPOSE

It has been reported that acute brief episodes of mental stress (MS) result in a prolonged increase in carotid-femoral pulse wave velocity (cfPWV), an index of aortic stiffness. However, whether acute MS also impacts arterial stiffness in other segments is unclear. The present study aimed to examine the impact of acute MS on segmental arterial stiffness.

METHODS

In the main experiment, 17 young male subjects (mean age, 20.1 ± 0.7 years) performed a 5-min MS and control (CON) task in a random order. Pulse wave velocity (PWV) from the heart to the brachium (hbPWV) and the ankle (haPWV), PWV between the brachial artery and the ankle (baPWV), and the cardio-ankle vascular index (CAVI) were simultaneously measured at baseline and 5, 15, and 30 min after the task.

RESULTS

Compared to baseline values, hbPWV, baPWV, haPWV, and CAVI significantly increased until 30 min after the MS task, whereas these variables did not significantly change following the CON task. At 5 and 30 min after the MS task, percentage changes from baseline were significantly higher in hbPWV (+ 5.2 ± 4.4 and 6.6 ± 4.9%) than in baPWV (+ 2.2 ± 2.1 and 2.2 ± 2.0%) or haPWV (+ 3.6 ± 2.6 and 4.3 ± 2.9%) and were also significantly lower in baPWV than in haPWV.

CONCLUSION

These findings suggest that acute MS elicits an increase in arterial stiffness in various segments and this arterial stiffening is not uniform among the segments.

Association Between Occupational, Sport, and Leisure Related Physical Activity and Baroreflex Sensitivity

Physical activity (PA) is a preventative behavior for noncommunicable disease. However, little consideration is given as to whether different domains of PA have differing associations with health outcomes. We sought to determine the association between occupational, sport, leisure, and total PA with baroreflex sensitivity (BRS), distinguishing between neural (nBRS) and mechanical (mBRS) BRS. In a cross-sectional analysis of 8649 adults aged 50 to 75 years, resting nBRS (estimated by low-frequency gain, from carotid distension rate and heart rate) and mBRS (carotid stiffness) were measured by high-precision carotid echo-tracking. PA was self-reported using the validated Baecke questionnaire. The associations between PA and nBRS and mBRS were quantified using multivariate linear regression analysis, separately in the working and nonworking population. In working adults (n=5039), occupational PA was associated with worse nBRS (unstandardized β=−0.02; [95% CI, −0.04 to −0.003]; P =0.022) whereas sport PA was associated with better nBRS (β=0.04; [95% CI, 0.02–0.07]; P =0.003) and mBRS (β=−0.05; [95% CI, −0.09 to −0.00001]; P =0.049). Neither leisure PA nor total PA was associated with nBRS or mBRS. In nonworking adults (n=3610), sport PA and total PA were associated with better mBRS (β=−0.08; [95% CI, −0.15 to 0.02]; P =0.012 and β=−0.05; [95% CI, −0.10 to 0.009]; P =0.018) but not nBRS. These findings suggest differential associations between domains of PA and BRS and may provide insights into the mechanisms underlying the association between occupational PA and cardiovascular disease.