Do early life exposures explain associations in mid-adulthood between workplace factors and risk factors for cardiovascular disease?

Systematic review and meta-analysis of the association between long working hours and hypertension risk

BACKGROUND

Hypertension, a major public health problem worldwide, has been linked to lifestyle factors and work conditions, with conflicting evidence on the association between long work hours and risk of hypertension.

METHODS

We conducted a systematic review and meta-analysis of observational studies to investigate the relationship between working hours and hypertension or blood pressure, assessed the risk of bias and performed subgroup analyses. The protocol was registered with the International Prospective Register of Systematic Reviews.

RESULTS

The pooled OR for the association between long working hours and risk of hypertension was 1.09 (95% CI: 0.88 to 1.35) in the 15 studies that used hypertension as the outcome. In the three studies that used blood pressure as the outcome, diastolic blood pressure was higher among those with long working hours compared with those with non-long working hours (1.24 mm Hg, 95% CI: 0.19 to 2.29). In subgroup analysis, the pooled OR for the association between long working hours and risk of hypertension was 1.28 (95% CI: 1.14 to 1.44) and 1.00 (95% CI: 0.64 to 1.56) in women and men, respectively.

CONCLUSIONS

Although this study could not clearly confirm the relationship between long working hours and hypertension, the subgroup analysis suggests that long working hours may be associated with hypertension, particularly among women. More reliable research is needed to establish causality.

PROSPERO REGISTRATION NUMBER

CRD42023406961.

Adulthood Psychosocial Disadvantages and Risk of Hypertension in U.S. Workers: Effect Modification by Adverse Childhood Experiences

Hypertension is a key driver of cardiovascular diseases. However, how stressors contribute to the development of hypertension remains unclear. The objective of this study was to examine prospective associations of adverse childhood experiences (ACEs) and adulthood psychosocial disadvantages (APDs) with incident hypertension. Data were from the Mid-life in the United States (MIDUS) study, a national, population-based, prospective cohort study. ACEs were examined via retrospective reports, and APDs including work stress and social isolation were assessed using survey measures. Incident hypertension was defined based on self-reported physician diagnosis. Baseline data were collected in 1995, with follow-up in 2004-2006 and 2013-2014. Cox proportional hazards regression was applied to assess prospective associations of ACEs and APDs with incident hypertension in 2568 workers free from hypertension at baseline. After adjustment for covariates, baseline APDs were associated with increased incident hypertension (aHR and 95% CI = 1.48 [1.09, 2.01]) during a 20-year follow-up, whereas ACEs showed null associations. Moreover, a moderating effect by ACEs was observed-the effect of APDs on risk of hypertension was stronger when ACEs were present (aHR and 95% CI = 1.83 [1.17, 2.86]). These findings underscore the importance of psychosocial stressors as nontraditional risk factors of cardiometabolic disorders.

Long Working Hours and the Prevalence of Masked and Sustained Hypertension

Previous studies on the effect of long working hours on blood pressure have shown inconsistent results. Mixed findings could be attributable to limitations related to blood pressure measurement and the lack of consideration of masked hypertension. The objective was to determine whether individuals who work long hours have a higher prevalence of masked and sustained hypertension. Data were collected at 3-time points over 5 years from 3547 white-collar workers. Long working hours were self-reported, and blood pressure was measured using Spacelabs 90207. Workplace clinic blood pressure was defined as the mean of the first 3readings taken at rest at the workplace. Ambulatory blood pressure was defined as the mean of the next readings recorded every 15 minutes during daytime working hours. Masked hypertension was defined as clinic blood pressure < 140/90 mm Hg and ambulatory blood pressure ≥135/85 mm Hg. Sustained hypertension was defined as clinic blood pressure ≥140/90 mm Hg and ambulatory blood pressure ≥135/85 mm Hg or being treated hypertension. Long working hours were associated with the prevalence of masked hypertension (prevalence ratio 49+ =1.70 [95% CI, 1.09–2.64]), after adjustment for sociodemographics, lifestyle-related risk factors, diabetes mellitus, family history of cardiovascular disease, and job strain. The association with sustained hypertension was of a comparable magnitude (prevalence ratio 49+ =1.66 [95% CI, 1.15–2.50]). Results suggest that long working hours are an independent risk factor for masked and sustained hypertension. Workplace strategies targeting long working hours could be effective in reducing the clinical and public health burden of hypertension.

Obesidade abdominal e padrões alimentares em mulheres trabalhadoras de turnos

Resumo Objetivou-se identificar os padrões alimentares e a associação destes com a obesidade abdominal em mulheres trabalhadoras de turnos no sul do Brasil. Para isso, realizou-se um estudo de caso-controle não pareado, incluindo um total de 541 mulheres de 18 a 53 anos de idade (215 casos; 326 controles). A presença de obesidade abdominal foi verificada pela aferição da circunferência da cintura ≥ 88 centímetros e os padrões alimentares foram obtidos por meio da análise de componentes principais de 53 itens. Os padrões foram classificados com base nos alimentos de maior carga fatorial e características nutricionais. A associação entre obesidade abdominal e os padrões foi verificada por meio de regressão logística não condicional. Três padrões alimentares foram identificados: “gordura animal/calorias”, “lanches/fast-food” e “frutas/verduras”. Após análise ajustada, os casos apresentaram uma maior chance de adesão ao padrão “frutas/verduras” (OR = 2,26; IC95%:1,30-3,93) e uma menor chance de adesão ao padrão “lanches/fast-food” (OR = 0,60; IC95%:0,36-1,01). Assim, identificou-se três padrões alimentares entre as trabalhadoras de turnos e verificou-se uma melhora na alimentação naquelas com obesidade abdominal, representando uma possível alteração de hábitos alimentares após sua ocorrência.

Effects of an internet-based lifestyle intervention on cardio-metabolic risks and stress in Korean workers with metabolic syndrome: a controlled trial

OBJECTIVE

This study examined the effects of an Internet-based Best Exerciser Super Trainer (BEST) program on cardio-metabolic risks and stress among workers with metabolic syndrome.

METHODS

This study utilized a non-randomized, pretest, and posttest, controlled design with a convenience sample of 48 Korean male workers. The workers in the BEST group participated in a 16-week Internet-based program: 150 min of regular physical activity per week, 200- to 300-kcal reduced daily diet for weight control, one-on-one counseling, and mobile phone text messages. Workers in the Education group received text messages and an educational booklet.

RESULTS

There were significant group by time interactions in cardio-metabolic risks: body weight (p = .022), visceral fat mass (p = .033), and waist circumference (p = .037). There was no group by time interaction in stress (p > .05); however, the BEST group showed a significantly greater reduction in health-related stress than those in the Education group (p = .025).

CONCLUSION

This study yielded evidence of the beneficial impact of the Internet-based BEST program for workers with metabolic syndrome on selected cardio-metabolic risks and health-related stress.

PRACTICE IMPLICATIONS

Internet-based one-on-one counseling and mobile phone text messages can assist individuals with targeted lifestyle modifications for metabolic syndrome.

Job demand and control in mid-life and physical and mental functioning in early old age: do childhood factors explain these associations in a British birth cohort?

OBJECTIVES

Adverse work-related exposures have been linked with decreased physical and mental functioning in later life, however, whether childhood factors explain the associations between work exposures and functioning is unknown. Our aim was to investigate if job demand and control in mid-life were related to self-reported physical and mental functioning in early old age and whether childhood factors explained these associations.

DESIGN

Prospective cohort study.

SETTING

England, Scotland and Wales.

PARTICIPANTS AND OUTCOME MEASURES

Data come from the UK Medical Research Council National Survey of Health and Development, a cohort with follow-up since birth in 1946. 1485 occupationally active study members had data available on job demand and control in mid-life and on physical and mental functioning assessed using the Short Form-36 questionnaire at 60-64 years.

RESULTS

Those with higher job control in mid-life had better physical functioning than those who reported lower job control (β 0.51, 95% CI 0.02 to 1.01, p=0.04 adjusted for adult confounders). Those with higher job demand in mid-life had poorer mental functioning (β -0.82, 95% CI -1.14 to -0.51, p<0.001). Associations between job control and mental functioning were similar but less pronounced. Adjustment for childhood factors (father's and mother's educational attainment, parents' interest in school at age 7 and cognitive ability at age 8) partially explained the association between job control and physical functioning, but did not explain the association between job demand and mental functioning.

CONCLUSIONS

Job demand and control in mid-life are differentially associated with mental and physical functioning in early old age and some of these associations may be partially explained by childhood factors.

Proximal and distal determinants of stressful work: framework and analysis of retrospective European data

Background

While robust evidence on associations of stressful work with health exists, less research is available on determinants of stressful work in terms of respondents' characteristics (proximal factors) and in terms of national labour market policies (distal factors). In this article we analyse proximal (childhood circumstances and labour market disadvantage) and distal determinants (national compensation and integration policies) of stressful work in a comprehensive framework.

Methods

We use data from the third wave of the Survey of Health, Ageing and Retirement in Europe (SHARE), with retrospective information on individual life courses collected among 11181 retired men and women in 13 European countries (2008–2009). To test our hypotheses we estimate multilevel regression models.

Results

Results show that stressful work is related to disadvantaged circumstances during childhood. To some extent this association is explained by labour market disadvantage during adulthood. Additionally, well developed labour market integration policies are related to lower overall levels of stressful work at national level.

Conclusion

This analysis provides first evidence of important determinants of stressful work, both in terms of pre-employment conditions (childhood circumstances) and in terms of contextual macro-social policies.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2458-14-849) contains supplementary material, which is available to authorized users.

Work stress is associated with diabetes and prediabetes: cross-sectional results from the MIPH Industrial Cohort Studies

BACKGROUND

Diabetes is rapidly rising globally, and the relation of psychosocial stress in workplace to diabetes and prediabetes is not well investigated.

PURPOSE

The aim of the study was to examine the association of work stress with diabetes and prediabetes in a sample of German industrial workers.

METHOD

In this cross-sectional survey of an occupational cohort (n = 2,674, 77 % male), work stress was measured by the Effort-Reward Imbalance (ERI) Questionnaire. Diabetic status, i.e., diabetes and prediabetes, were diagnosed by glycated hemoglobin A1c criterion or fasting plasma glucose criterion supplemented by self-reports.

RESULTS

The overall prevalence rates of diabetes and prediabetes were 3.5 and 42.2 %, respectively. Using ordinal logistic regression with adjustment for potential confounding factors, high ERI at work was associated with diabetes-related ordinal variable (odds ratio [OR], 1.27; 95 % confidence interval [95 % CI], 1.02-1.58) and prediabetes-related ordinal variable (OR, 1.26; 95 % CI, 1.01-1.58) in men, whereas the associations in women were somewhat less pronounced and did not reach statistical significance.

CONCLUSION

The findings indicate that work stress in terms of ERI is associated with diabetes and prediabetes in German industrial male workers. If supported by prospective evidence, results point to a new approach towards primary prevention of diabetes.

Work organization, job insecurity, and occupational health disparities

BACKGROUND

Changes in employment conditions in the global economy over the past 30 years have led to increased job insecurity and other work organization hazards. These hazards may play a role in creating and sustaining occupational health disparities by socioeconomic position, gender, race, ethnicity, and immigration status.

METHODS

A conceptual model was developed to guide the review of 103 relevant articles or chapters on the role of work organization and occupational health disparities identified through a comprehensive search conducted by NIOSH. A second review was conducted of employment and workplace policies and programs designed to reduce the health and safety risks due to job insecurity and other work organization hazards.

RESULTS

There is consistent evidence that workers in lower socioeconomic or social class positions are exposed to greater job insecurity and other work organization hazards than workers in higher socioeconomic positions. Likewise, racial and ethnic minorities and immigrants are exposed to greater job insecurity. Limited research examining the effects of interventions targeting work organization hazards on disparities has been conducted; nonetheless, intervention strategies are available and evidence suggests they are effective.

CONCLUSIONS

Job insecurity and work organization hazards play a role in creating and sustaining occupational health disparities. Employment and workplace policies and programs have the potential to reduce these hazards, and to reduce disparities.

Long working hours and coronary heart disease: a systematic review and meta-analysis

The authors aggregated the results of observational studies examining the association between long working hours and coronary heart disease (CHD). Data sources used were MEDLINE (through January 19, 2011) and Web of Science (through March 14, 2011). Two investigators independently extracted results from eligible studies. Heterogeneity between the studies was assessed using the I² statistic, and the possibility of publication bias was assessed using the funnel plot and Egger's test for small-study effects. Twelve studies were identified (7 case-control, 4 prospective, and 1 cross-sectional). For a total of 22,518 participants (2,313 CHD cases), the minimally adjusted relative risk of CHD for long working hours was 1.80 (95% confidence interval (CI): 1.42, 2.29), and in the maximally (multivariate-) adjusted analysis the relative risk was 1.59 (95% CI: 1.23, 2.07). The 4 prospective studies produced a relative risk of 1.39 (95% CI: 1.12, 1.72), while the corresponding relative risk in the 7 case-control studies was 2.43 (95% CI: 1.81, 3.26). Little evidence of publication bias but relatively large heterogeneity was observed. Studies varied in size, design, measurement of exposure and outcome, and adjustments. In conclusion, results from prospective observational studies suggest an approximately 40% excess risk of CHD in employees working long hours.

Social adversity in adolescence increases the physiological vulnerability to job strain in adulthood: a prospective population-based study

Background

It has been argued that the association between job strain and health could be confounded by early life exposures, and studies have shown early adversity to increase individual vulnerability to later stress. We therefore investigated if early life exposure to adversity increases the individual's physiological vulnerability job strain in adulthood.

Methodology/Principal Findings

In a population-based cohort (343 women and 330 men, 83% of the eligible participants), we examined the association between on the one hand exposure to adversity in adolescence, measured at age 16, and job strain measured at age 43, and on the other hand allostatic load at age 43. Adversity was operationalised as an index comprising residential mobility and crowding, parental loss, parental unemployment, and parental physical and mental illness (including substance abuse). Allostatic load summarised body fat, blood pressure, inflammatory markers, glucose, blood lipids, and cortisol regulation. There was an interaction between adversity in adolescence and job strain (B = 0.09, 95% CI 0.02 to 0.16 after adjustment for socioeconomic status), particularly psychological demands, indicating that job strain was associated with increased allostatic load only among participants with adversity in adolescence. Job strain was associated with lower allostatic load in men (β = −0.20, 95% CI −0.35 to −0.06).

Conclusions/Significance

Exposure to adversity in adolescence was associated with increased levels of biological stress among those reporting job strain in mid-life, indicating increased vulnerability to environmental stressors.