Occupational physical activity predicts baseline and 8-year progression of carotid atherosclerosis among women

INTRODUCTION

Recent reviews link higher levels of occupational physical activity (OPA) to cardiovascular disease (CVD). However, the evidence for women is inconsistent and studies of activity-limiting symptomatic CVD are prone to healthy worker survivor effect. To address these limitations, this study investigated OPA effects on asymptomatic carotid artery intima-media thickness (IMT) among women.

METHODS

Participants include 905 women from the population-based Kuopio Ischemic Heart Disease Risk Factor Study with baseline (1998-2001) data on self-reported OPA and sonographic measurement of IMT. Linear mixed models with adjustment for 15 potential confounders estimated and compared mean baseline IMT and 8-year IMT progression for five levels of self-reported OPA. Analyses stratified by cardiovascular health and retirement status were planned because strong interactions between preexisting CVD and OPA intensity have previously been reported.

RESULTS

Light standing work, moderately heavy active work, and heavy or very heavy physical work were all consistently associated with greater baseline IMT and 8-year IMT progression than light sitting work. The greatest baseline IMT was observed for heavy or very heavy physical work (1.21 mm), and the greatest 8-year IMT progression for light standing work and moderately heavy active work (both 0.13 mm), 30% above sitting work (0.10 mm). Stratified analyses showed that these differences were driven by much stronger OPA effects among women with baseline carotid artery stenosis. Retired women experienced slower IMT progression than those working at baseline.

CONCLUSIONS

Higher levels of OPA predict higher baseline IMT and 8-year IMT progression, especially among women with baseline stenosis.

Re: Cillekens B, Huysmans MA, Holtermann A, van Mechelen W, Straker L, Krause N, van der Beek AJ, Coenen P. Physical activity at work may not be health enhancing. A systematic review with meta-analysis on the association between occupational physical activity and cardiovascular disease mortality covering 23 studies with 655 892 participants. Scand J Work Environ Health. 2022;48(2):86-98. doi:10.5271/sjweh.3993

Objectives

Emerging evidence suggests contrasting health effects for leisure-time and occupational physical activity. In this systematic review, we synthesized and described the epidemiological evidence regarding the association between occupational physical activity and cardiovascular disease (CVD) mortality.

Methods

A literature search was performed in PubMed, Embase, CINAHL, PsycINFO and Evidence-Based Medicine Reviews, from database inception to 17 April 2020. Articles were included if they described original observational prospective research, assessing the association between occupational physical activity and CVD mortality among adult workers. Reviews were included if they controlled for age and gender and at least one other relevant variable. We performed meta-analyses on the associations between occupational physical activity and CVD mortality.

Results

We screened 3345 unique articles, and 31 articles (from 23 studies) were described in this review. In the meta-analysis, occupational physical activity showed no significant association with overall CVD mortality for both males [hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.84–1.12] and females (HR 0.97, 95% CI 0.82–1.15). Additional analysis showed that higher levels of occupational physical activity were non-significantly associated with a 9% increase in studies reporting on the outcome ischemic heart disease mortality (HR 1.09, 95% CI 0.82–1.43).

Conclusions

While the beneficial association between leisure-time physical activity and CVD mortality has been widely documented, occupational physical activity was not found to have a beneficial association with CVD mortality. This observation may have implications for our appreciation of the association between physical activity and health for workers in physically demanding jobs, as occupational physical activity may not be health enhancing.

Assessment of cardiovascular load among hotel room cleaners

Hotel room cleaners are a vulnerable population at risk for cardiovascular disease. To evaluate their workload heart rate (HR), % heart rate reserve (%HRR), blood pressure (BP), metabolic equivalent (MET), and energy expenditure (EE) were measured over two workdays and two off-workdays. The mean age was 45.5 (SD 8.2) years with a mean 10.4 (SD 7.8) years of work experience. Mean average and peak HR, %HRR, MET, and EE were significantly higher during a workday than an off-workday for the entire work shift, first and last hour of work. Mean average HR and %HRR saw the largest increase between the lunch and post-lunch interim. One-fourth of subjects exceeded the recommended 30% HRR threshold for 8-hour shifts. Some workers experienced a substantial increase in HR and DBP over a workday indicating physiologic fatigue and thus may be at increased risk for cardiovascular disease and premature death due to excessive physical work demands.

Physical activity at work may not be health enhancing. A systematic review with meta-analysis on the association between occupational physical activity and cardiovascular disease mortality covering 23 studies with 655 892 participants

OBJECTIVES

Emerging evidence suggests contrasting health effects for leisure-time and occupational physical activity. In this systematic review, we synthesized and described the epidemiological evidence regarding the association between occupational physical activity and cardiovascular disease (CVD) mortality.

METHODS

A literature search was performed in PubMed, Embase, CINAHL, PsycINFO and Evidence-Based Medicine Reviews, from database inception to 17 April 2020. Articles were included if they described original observational prospective research, assessing the association between occupational physical activity and CVD mortality among adult workers. Reviews were included if they controlled for age and gender and at least one other relevant variable. We performed meta-analyses on the associations between occupational physical activity and CVD mortality.

RESULTS

We screened 3345 unique articles, and 31 articles (from 23 studies) were described in this review. In the meta-analysis, occupational physical activity showed no significant association with overall CVD mortality for both males [hazard ratio (HR) 1.00, 95% confidence interval (CI) 0.87-1.15] and females (HR 0.95, 95% CI 0.82-1.09). Additional analysis showed that higher levels of occupational physical activity were non-significantly associated with a 15% increase in studies reporting on the outcome ischemic heart disease mortality (HR 1.15, 95% CI 0.88-1.49).

CONCLUSIONS

While the beneficial association between leisure-time physical activity and CVD mortality has been widely documented, occupational physical activity was not found to have a beneficial association with CVD mortality. This observation may have implications for our appreciation of the association between physical activity and health for workers in physically demanding jobs, as occupational physical activity may not be health enhancing.

Occupational risk factors for work disability following carpal tunnel syndrome: a pooled prospective study

Background

Although recent studies have identified important risk factors associated with incident carpal tunnel syndrome (CTS), risk factors associated with its severity have not been well explored.

Objective

To examine the associations between personal, workplace psychosocial and biomechanical factors and incident work disability among workers with CTS.

Methods

Between 2001 and 2010 five research groups conducted coordinated prospective studies of CTS and related work disability among US workers from various industries. Workers with prevalent or incident CTS (N=372) were followed for up to 6.4 years. Incident work disability was measured as: (1) change in work pace or work quality, (2) lost time or (3) job change following the development of CTS. Psychosocial factors were assessed by questionnaire. Biomechanical exposures were assessed by observation and measurements and included force, repetition, duty cycle and posture. HRs were estimated using Cox models.

Results

Disability incidence rates per 100 person-years were 33.2 for changes in work pace or quality, 16.3 for lost time and 20.0 for job change. There was a near doubling of risk for job change among those in the upper tertile of the Hand Activity Level Scale (HR 2.17; 95% CI 1.17 to 4.01), total repetition rate (HR 1.75; 95% CI 1.02 to 3.02), % time spent in all hand exertions (HR 2.20; 95% CI 1.21 to 4.01) and a sixfold increase for high job strain. Sensitivity analyses indicated attenuation due to inclusion of the prevalent CTS cases.

Conclusion

Personal, biomechanical and psychosocial job factors predicted CTS-related disability. Results suggest that prevention of severe disability requires a reduction of both biomechanical and organisational work stressors.

BET1 variants establish impaired vesicular transport as a cause for muscular dystrophy with epilepsy

BET1 is required, together with its SNARE complex partners GOSR2, SEC22b, and Syntaxin-5 for fusion of endoplasmic reticulum-derived vesicles with the ER-Golgi intermediate compartment (ERGIC) and the cis-Golgi. Here, we report three individuals, from two families, with severe congenital muscular dystrophy (CMD) and biallelic variants in BET1 (P1 p.(Asp68His)/p.(Ala45Valfs*2); P2 and P3 homozygous p.(Ile51Ser)). Due to aberrant splicing and frameshifting, the variants in P1 result in low BET1 protein levels and impaired ER-to-Golgi transport. Since in silico modeling suggested that p.(Ile51Ser) interferes with binding to interaction partners other than SNARE complex subunits, we set off and identified novel BET1 interaction partners with low affinity for p.(Ile51Ser) BET1 protein compared to wild-type, among them ERGIC-53. The BET1/ERGIC-53 interaction was validated by endogenous co-immunoprecipitation with both proteins colocalizing to the ERGIC compartment. Mislocalization of ERGIC-53 was observed in P1 and P2's derived fibroblasts; while in the p.(Ile51Ser) P2 fibroblasts specifically, mutant BET1 was also mislocalized along with ERGIC-53. Thus, we establish BET1 as a novel CMD/epilepsy gene and confirm the emerging role of ER/Golgi SNAREs in CMD.

Physical activity at work may not be health enhancing. A systematic review with meta-analysis on the association between occupational physical activity and cardiovascular disease mortality covering 23 studies with 655 892 participants

Objectives

Emerging evidence suggests contrasting health effects for leisure-time and occupational physical activity. In this systematic review, we synthesized and described the epidemiological evidence regarding the association between occupational physical activity and cardiovascular disease (CVD) mortality.

Methods

A literature search was performed in PubMed, Embase, CINAHL, PsycINFO and Evidence-Based Medicine Reviews, from database inception to 17 April 2020. Articles were included if they described original observational prospective research, assessing the association between occupational physical activity and CVD mortality among adult workers. Reviews were included if they controlled for age and gender and at least one other relevant variable. We performed meta-analyses on the associations between occupational physical activity and CVD mortality.

Results

We screened 3345 unique articles, and 31 articles (from 23 studies) were described in this review. In the meta-analysis, occupational physical activity showed no significant association with overall CVD mortality for both males [hazard ratio (HR) 1.00, 95% confidence interval (CI) 0.87–1.15] and females (HR 0.95, 95% CI 0.82–1.09). Additional analysis showed that higher levels of occupational physical activity were non-significantly associated with a 15% increase in studies reporting on the outcome ischemic heart disease mortality (HR 1.15, 95% CI 0.88–1.49).

Conclusions

While the beneficial association between leisure-time physical activity and CVD mortality has been widely documented, occupational physical activity was not found to have a beneficial association with CVD mortality. This observation may have implications for our appreciation of the association between physical activity and health for workers in physically demanding jobs, as occupational physical activity may not be health enhancing.

Blood Pressure Changes After a Health Promotion Program Among Mexican Workers

Background: Cardiovascular disease is becoming increasingly prevalent in low and middle-income countries (LMIC), and high blood pressure (BP) is one of the main risk factors. The efficacy and sustainability of worksite health promotion (WHP) programs for BP reduction in LMIC have yet to be determined. Methods: This non-randomized company-based trial evaluated 6- and 12-months effects of a WHP intervention on BP among 2,002 participating workers from seven Mexican companies. Intervention and control groups were assigned at the company level. The intervention included nutrition counseling, physical exercise, and stress management components. Mixed models assessed differences in BP change between intervention and control companies in intent-to-treat (ITT), per-protocol (PerP), and as-treated (AsTr) analyses, and also within-group changes stratified by company, intervention component, and baseline cardiovascular risk factor levels. All analyses were adjusted for potential confounders. We accounted for missing data and loss to follow-up using inverse probability of censoring weighting. Results: ITT analyses revealed mean BP change differences of -1.1 mmHg at 12 months (95% CI: -2.9; 0.6) in intervention companies relative to control companies. PerP and AsTr analyses confirmed this finding. Within-group analyses showed consistent BP reductions at both 6 and 12 months. Substantial differences in BP changes ranging from diastolic -6.1 mmHg, (95% CI: -11.2; -1.2) to systolic -13.0 mmHg (95% CI: -16.0; -10.1) were found among individuals with diabetes at baseline in intervention companies relative to control companies. Conclusion: After 1 year, WHP was associated with modest but uncertain BP reductions. Substantial reductions were mainly observed among diabetic workers.

Associations between occupational relative aerobic workload and resting blood pressure among different age groups: a cross-sectional analysis in the DPhacto study

OBJECTIVE

High levels of occupational physical activity (OPA) increase heart rate, blood pressure (BP) and the risk of hypertension. Older workers may be more vulnerable to high levels of OPA due to age-related degeneration of the cardiovascular system and cardiorespiratory fitness. This study investigates the association of relative aerobic workload (RAW) with resting BP and examines if this relation is moderated by age.

DESIGN

Cross-sectional epidemiological study.

SETTING

Data were collected among employees of 15 Danish companies in the cleaning, manufacturing and transport sectors.

PARTICIPANTS

2107 employees were invited for participation, of these 1087 accepted and 562 (42% female and 4% non-Westerns) were included in the analysis based on the criteria of being non-pregnant, no allergy to bandages, sufficient amount of heart rate data corresponding to ≥4 work hours per workday or 75% of average work hours, and no missing outcome and confounder values.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was BP.

RESULTS

Heart rate reserve was estimated from ambulatory 24-hour heart rate measures covering 2.5 workdays per participant (SD 1.0 day). Age significantly moderated the association between RAW and BP. Mean intensity and duration of high RAW (≥30% heart rate reserve) showed positive associations with diastolic BP and negative associations with pulse pressure (PP) among participants ≥47 years old. Tendencies towards negative associations between RAW and BP were seen among participants <47 years old.

CONCLUSIONS

Mean intensity and duration of RAW increased diastolic BP among participants ≥47 years old. Negative associations with PP may be due to healthy worker selection bias. Prevention of hypertension should consider reductions in RAW for ageing workers.

Occupational physical activity and all-cause and cardiovascular disease mortality: Results from two longitudinal studies in Switzerland

BACKGROUND

Research regarding the effects of occupational physical activity on health remains inconsistent. We analyzed the association of occupational physical activity with all-cause and cardiovascular disease (CVD) mortality.

METHODS

We analyzed two cohorts with baseline assessments from 1977 to 1993 ("National Research Program 1A" (NRP1A) and "MONItoring of trends and determinants in CArdiovascular disease" [MONICA]) and mortality follow-up until 2015 using adjusted Cox regression models.

RESULTS

We included 4396 NRP1A participants (137 793 person-years of follow-up, 1541 deaths) and 5780 MONICA participants (135 410 person-years, 1158 deaths). All-cause mortality was higher for men in the high compared with the low occupational physical activity category according to NRP1A (hazard ratio [HR] 1.25, 95% confidence intervals [CI] 1.05-1.50). CVD mortality was higher for men in the moderate compared with the low occupational physical activity category according to MONICA (HR, 1.41; 95% CI, 1.03-1.91). Results for women were not statistically significant.

CONCLUSIONS

We observed higher total and CVD mortality risks in men with higher occupational physical activity but inconsistent results for women and across cohorts.

Effort-reward imbalance and ambulatory blood pressure among female Las Vegas hotel room cleaners

BACKGROUND

Effort-reward imbalance (ERI) was hypothesized to be associated with ambulatory blood pressure (ABP) and pulse pressure (PP) among female hotel room cleaners.

METHODS

ERI, ABP, and PP were assessed among 419 cleaners from five hotels during 18 waking hours. Adjusted linear regression models were used to assess associations of ERI with ABP and PP during 18-hours, work hours, and after work hours.

RESULTS

There was a pattern of higher ERI being associated with higher 18-hour systolic ABP and 18-hour PP although the results were imprecise. An increase of ERI by half its range was associated with a 1.6 mmHg (95% CI, -1.6-4.7) increase in 18-hour systolic blood pressure (SBP) and a 0.7 mmHg (95% CI, -1.1-2.5) increase in 18-hour PP. An increase in rewards by half its range was associated with a 2 mmHg decrease in after-hours SBP (-2.2, 95% CI, -5.4-1.0) and after-hours PP (-1.9, 95% CI, -3.8-0.0). Among females 45 years or older, ERI was associated with 2.1 and 2.2 mmHg increase in 18-hour and work hours diastolic ABP, respectively, compared to a 0 mmHg change in 18-hour and work hours diastolic ABP in younger women. The number of dependents at home attenuated the association.

CONCLUSIONS

ERI was positively associated with ABP, particularly SBP, and the association was modified by age and the number dependents at home, although the estimates were imprecise. Workplace interventions that integrate stress management and active ABP surveillance appear warranted. However, larger studies with Latina women need to confirm our results.

Exploring the interplay between job strain and different domains of physical activity on the incidence of coronary heart disease in adult men

AIMS

The aim of this study was to investigate the independent associations of occupational (OPA) and sport physical activity (SpPA) and job strain on the incidence of coronary heart disease (CHD) events, and to explore their interplay.

METHODS

The study sample included 3310 25-64-year-old employed men, free of CHD at baseline, recruited in three population-based and one factory-based cohorts. OPA and SpPA, and job strain were assessed by the Baecke and the Job Content Questionnaires, respectively. We estimated the associations between different domains of physical activity and job strain with CHD, adjusting for major risk factors using Cox models.

RESULTS

During follow-up (median=14 years), 120 CHD events, fatal and non-fatal, occurred. In the entire sample, a higher CHD risk was found for high job strain (hazard ratio=1.55, 95% confidence interval: 1.05-2.31). The joint effect of low OPA and high job strain was estimated as a hazard ratio of 2.53 (1.29-4.97; reference intermediate OPA with non-high strain). With respect to intermediate OPA workers, in stratified analysis when SpPA is none, low OPA workers had a hazard ratio of 2.13 (95% confidence interval: 1.19-3.81), increased to 3.95 (1.79-8.78) by the presence of high job strain. Low OPA-high job strain workers take great advantage from SpPA, reducing their risk up to 90%. In contrast, the protective effect of SpPA on CHD in other OPA-job strain categories was modest or even absent, in particular when OPA is high.

CONCLUSIONS

Our study shows a protective effect of recommended and intermediate SpPA levels on CHD risk among sedentary male workers. When workers are jointly exposed to high job strain and sedentary work their risk further increases, but this group benefits most from regular sport physical activity.

Occupational and leisure-time physical activity differentially predict 6-year incidence of stroke and transient ischemic attack in women

Objectives Recent meta-analyses suggest a physical activity health paradox: high levels of occupational physical activity (OPA) increase cardiovascular disease (CVD) risk, while leisure-time physical activity (LTPA) decreases risk. However, studies of women and cerebrovascular disease are limited. This report examines physical activity effects on stroke and transient ischemic attack (TIA) among working women in the United States. Methods OPA history, health status, and lifestyle were assessed by baseline interviews of 31 270 employed Sister Study participants aged 35-74 years. OPA was assessed at six intensity levels (lowest: "mostly sitting"); the highest three were combined as "high intensity work." Independent OPA and LTPA effects on 6-year cerebrovascular disease incidence were estimated in adjusted Cox proportional hazard models. Results Stroke (N=441) and TIA (N=274) risk increased with more standing and higher intensity work at current and longest held job. Compared with mostly sitting, high intensity work at the current job increased TIA risk by 57% [hazard ratio (HR) 1.57, 95% confidence interval (CI) 1.04-2.38]. High intensity OPA at the longest held job increased risk for stroke by 44% (HR 1.44; 95% CI 1.08-1.93). Among women with CVD, sitting and standing equally, especially at the current job, increased risks up to two-fold (TIA HR 1.98, 95% CI 1.10-3.55) compared with mostly sitting at work. LTPA showed inverse associations. Conclusions Higher intensity levels of OPA increased stroke and TIA risks, while LTPA decreased risks; results corroborate the physical activity health paradox for women and cerebrovascular disease. More standing at work increased cerebrovascular disease risks, especially for women with CVD.

Job strain associated with increases in ambulatory blood and pulse pressure during and after work hours among female hotel room cleaners

BACKGROUND

Previously documented elevated hypertension rates among Las Vegas hotel room cleaners are hypothesized to be associated with job strain.

METHODS

Job strain was assessed by questionnaire. Ambulatory blood pressure (ABP) was recorded among 419 female cleaners from five hotels during 18 waking hours. Multiple linear regression models assessed associations of job strain with ABP and pulse pressure for 18-h, work hours, and after work hours.

RESULTS

Higher job strain was associated with increased 18-h systolic ABP, after work hours systolic ABP, and ambulatory pulse pressure. Dependents at home but not social support at work attenuated effects. Among hypertensive workers, job strain effects were partially buffered by anti-hypertensive medication.

CONCLUSIONS

High job strain is positively associated with blood pressure among female hotel workers suggesting potential for primary prevention at work. Work organizational changes, stress management, and active ABP surveillance and hypertension management should be considered for integrated intervention programs.

Do highly physically active workers die early? A systematic review with meta-analysis of data from 193 696 participants

Objective

Recent evidence suggests the existence of a physical activity paradox, with beneficial health outcomes associated with leisure time physical activity, but detrimental health outcomes for those engaging in high level occupational physical activity. This is the first quantitative systematic review of evidence regarding the association between occupational physical activity and all-cause mortality.

Design

Systematic review with meta-analysis.

Data source

A literature search was performed in electronic databases PubMed, Embase, CINAHL, PsycINFO and Cochrane.

Eligibility criteria for selecting studies

We screened for peer reviewed articles from prospective studies assessing the association of occupational physical activity with all-cause mortality. A meta-analysis assessed the association of high (compared with low) level occupational physical activity with all-cause mortality, estimating pooled hazard ratios (HR) (with 95% CI).

Results

2490 unique articles were screened and 33 (from 26 studies) were included. Data from 17 studies (with 193 696 participants) were used in a meta-analysis, showing that men with high level occupational physical activity had an 18% increased risk of early mortality compared with those engaging in low level occupational physical activity (HR 1.18, 95% CI 1.05 to 1.34). No such association was observed among women, for whom instead a tendency for an inverse association was found (HR 0.90, 95% CI 0.80 to 1.01).

Conclusions

The results of this review indicate detrimental health consequences associated with high level occupational physical activity in men, even when adjusting for relevant factors (such as leisure time physical activity). These findings suggest that research and physical activity guidelines may differentiate between occupational and leisure time physical activity.

Physical activity and 22-year all-cause and coronary heart disease mortality

BACKGROUND

This study explores the effects of occupational (OPA) and leisure time physical activity (LTPA) on mortality relative to cardiorespiratory fitness and pre-existing coronary heart disease (CHD).

METHODS

Associations between OPA, measured as energy expenditure (kcal/day) and relative aerobic workload (%VO₂ max), LTPA, and 22-year mortality among 1891 Finnish men were assessed by Cox regression models stratified by CHD and adjusted for 19 confounders.

RESULTS

In fully adjusted models, each 10% of relative aerobic workload increased all-cause mortality by 13% and CHD mortality 28% (P < 0.01). Compared to healthy subjects, men with CHD experienced lower mortality risks due to OPA and higher risks due to LTPA. While LTPA had no effect among healthy men, in men with CHD each weekly hour of conditioning LTPA increased all-cause mortality risks by 10% and CHD mortality by14%.

CONCLUSION

OPA was positively associated with both all-cause and CHD mortality. LTPA was not protective. Among men with CHD, LTPA increased mortality risks.

Parental occupational exposures and the risk of childhood sporadic retinoblastoma: a report from the Children's Oncology Group

OBJECTIVES

We examined associations between parental occupational chemical exposures up to 10 years before conception and the risk of sporadic retinoblastoma among offspring.

METHODS

In our multicentre study on non-familial retinoblastoma, parents of 187 unilateral and 95 bilateral cases and 155 friend controls were interviewed by telephone. Exposure information was collected retroactively through a detailed occupational questionnaire that asked fathers to report every job held in the 10 years before conception, and mothers 1 month before and during the index pregnancy. An industrial hygienist reviewed all occupational data and assigned an overall exposure score to each job indicating the presence of nine hazardous agents.

RESULTS

We estimated elevated ORs for unilateral and bilateral retinoblastoma among offspring of fathers who were exposed to polycyclic aromatic hydrocarbons or paints in the 10 years before conception. However, only for exposure to paints did confidence limits exclude the null for bilateral disease (OR: 8.76, 95% CI: 1.32 to 58.09). Maternal prenatal exposure to at least one of the nine agents was related to increased risk of unilateral disease in their children (OR: 5.25, 95% CI: 1.14 to 24.16). Fathers exposed to at least one of the nine agents and who were ≥30 years of age were at increased risk of having a child diagnosed with bilateral retinoblastoma (OR: 6.59, 95% CI: 1.34 to 32.42).

CONCLUSIONS

Our results suggest a role for several hazardous occupational exposures in the development of childhood retinoblastoma.

Does Aerobic Exercise Increase 24-Hour Ambulatory Blood Pressure Among Workers With High Occupational Physical Activity?-A RCT

OBJECTIVE

High occupational physical activity (OPA) increases cardiovascular risk and aerobic exercise has been recommended for reducing this risk. This paper investigates the effects of an aerobic exercise intervention on 24-hour ambulatory blood pressure (ABP) among cleaners with high OPA.

METHODS

Hundred and sixteen cleaners between 18 and 65 years were randomized. During the 4-month intervention period, the aerobic exercise group (AE) (n = 57) performed worksite aerobic exercise (2 × 30 minutes/week), while the reference group (REF) (n = 59) attended lectures. Between-group differences in 4-month ABP changes were evaluated by intention-to-treat analysis using a repeated-measure 2 × 2 multiadjusted mixed-models design.

RESULTS

Relative to REF, 24-hour ABP significantly increased in AE: systolic 3.6 mm Hg (95% confidence interval (CI) 1.6–5.7) and diastolic 2.3 mm Hg (95% CI 0.9–3.8). Cleaners with high aerobic workload exhibited particularly high 24-hour ABP increases: systolic 6.0 mm Hg (95% CI 2.4–9.6), and diastolic 3.8 mm Hg (95% CI 1.3–6.4).

CONCLUSION

Aerobic exercise increased 24-hour ABP among cleaners. This adverse effect raises questions about the safety and intended benefits of aerobic exercise, especially among workers with high OPA and a demanding aerobic workload.

http://www.controlled-trials.com/ISRCTN86682076. Unique identifier ISRCTN86682076.

CLINICAL TRIAL REGISTRATION

Trial Number ISRCTN86682076.

Course of Depressive Symptoms Following a Workplace Injury: A 12-Month Follow-Up Update

Introduction To estimate the prevalence, incidence and course of depressive symptoms, their relationship with return-to-work, and prevalence of depression diagnosis/treatment 12 months following a lost-time workplace musculoskeletal injury. Methods In a prospective cohort study, 332 workers' compensation claimants with a back or upper extremity musculoskeletal disorder completed interviews at 1, 6 and 12 months post-injury. Participants self-reported they had not received a depression diagnosis 1 year pre-injury. Cutoff of 16 on the CES-D defined a high level of depressive symptoms. Self-reported data on depression diagnosis and treatment and work status since injury were collected. Results Cumulative incidence of high depressive symptom levels over 12 months was 50.3 % (95 % CI 44.9-55.7 %). At 12 months, 24.7 % (95 % CI 20.1-29.3 %) of workers exhibited high levels. Over 12 months, 49.7 % (95 % CI 44.3-55.1 %) had low levels at all 3 interviews, 14.5 % (95 % CI 10.7-18.2 %) had persistently high levels, and 25.6 % (95 % CI 20.9-30.3 %) demonstrated improvements. Among workers with low baseline levels, incidence of high levels at 12 months was 6.0 % (95 % CI 2.7-9.3 %). For workers with high baseline levels, 36.1 % (95 % CI 27.9-44.3 %) exhibited persistent high symptoms at 6 and 12 months, while 38.4 % (95 % CI 30.1-46.6 %) experienced low levels at 6 and 12 months. Problematic RTW outcomes were common among workers with a poor depressive symptom course. Among workers with persistent high symptoms, 18.8 % (95 % CI 7.7-29.8 %) self-reported receiving a depression diagnosis by 12 months and 29.2 % (95 % CI 16.3-42.0 %) were receiving treatment at 12 months. Conclusions Depressive symptoms are common in the first year following a lost-time musculoskeletal injury and a poor depressive symptom course is associated with problematic RTW outcomes 12 months post-injury. While symptoms appear to improve over time, the first 6 months appear to be important in establishing future symptom levels and may represent a window of opportunity for early screening.

Lifetime occupational and leisure time physical activity and risk of Parkinson's disease

INTRODUCTION

While regular exercise has been shown to alleviate the motor symptoms of Parkinson's disease (PD), it remains unclear whether a physically active lifestyle may prevent PD.

METHODS

To examine physical activities across the lifespan and risk of PD, we relied on data from a population-based case-control study that enrolled 357 incident PD cases and 341 controls. We assessed physical activity levels via self-report of (1) overall physical activity (PA) over 4 age periods; (2) competitive sports; and (3) occupational histories.

RESULTS

PD risks were lower comparing the overall PA highest quartile (moderate to vigorous activities ≥180 metabolic equivalent task-hours/week (MET-h/wk)) with the lowest quartile (<47.8 MET-h/wk) in age-period 18-24 years (adjusted odds ratio (OR) 0.64, 95% confidence interval (CI) 0.40-1.02), and 45-64 years (OR 0.50, 95%CI 0.31-0.83) but not in age-period 25-44. Individuals who consistently engaged in overall PA at high levels (before age 65 years) had a 51% lower PD risk than those with low levels. Also, having participated in competitive sports prior to age 25 was inversely associated with PD (OR 0.53, 95% CI 0.31-0.91 for high level versus never). There was no association for measures of occupational physical activity though.

CONCLUSION

The long prodromal stage of PD makes it difficult to conclude whether insidious disease leads to a reduction of physical activity years before motor symptom onset and PD diagnosis. However, sports activities and high levels of overall PA in youth appear protective unless they are markers for biologic or genetic factors that lower PD risk.

Psychosocial job factors and biological cardiovascular risk factors in Mexican workers

BACKGROUND

Psychosocial job factors (PJF) have been implicated in the development of cardiovascular disease. The paucity of data from developing economies including Mexico hampers the development of worksite intervention efforts in those regions.

METHODS

This cross-sectional study of 2,330 Mexican workers assessed PJF (job strain [JS], social support [SS], and job insecurity [JI]) and biological cardiovascular disease risk factors [CVDRF] by questionnaire and on-site physical examinations. Alternative formulations of the JS scales were developed based on factor analysis and literature review. Associations between both traditional and alternative job factor scales with CVDRF were examined in multiple regression models, adjusting for physical workload, and socio-demographic factors.

RESULTS

Alternative formulations of the job demand and control scales resulted in substantial changes in effect sizes or statistical significance when compared with the original scales. JS and JI showed hypothesized associations with most CVDRF, but they were inversely associated with diastolic blood pressure and some adiposity measures. SS was mainly protective against CVDRF.

CONCLUSION

Among Mexican workers, alternative PJF scales predicted health outcomes better than traditional scales, and psychosocial stressors were associated with most CVDRF.

Work schedules and 11-year progression of carotid atherosclerosis in middle-aged Finnish men

OBJECTIVES

This study investigated the relationship between different work schedules and progression of carotid atherosclerosis, an early indicator of cardiovascular disease (CVD).

METHODS

We studied 621 men, aged 42-60 years, in the prospective Kuopio Ischemic Heart Disease Risk Factor Study cohort. Using multivariable regressions adjusting for 22 covariates including total time worked during follow-up, we evaluated the associations of baseline work schedules with 11-year progression of ultrasonographically assessed carotid intima-media thickness (IMT), and their variation by preexisting CVD.

RESULTS

Standard daytime work, weekend shifts, and evening/night/rotating shifts were associated with 31%, 37%, and 33% increases in IMT, respectively. Compared to daytime workers, weekend workers experienced a faster progression of carotid atherosclerosis [relative change ratio (RCR) = 1.05, 95% CI: 1.00-1.09)]. This ratio was higher among men who had preexisting CVD.

CONCLUSIONS

Weekend shifts, more than standard daytime work, appear to accelerate carotid atherosclerosis progression among middle-aged Finnish men, especially those with pre-existing CVD.

Does aerobic exercise improve or impair cardiorespiratory fitness and health among cleaners? A cluster randomized controlled trial

OBJECTIVE

It is unknown if aerobic exercise overloads or improves the cardiovascular system among workers with high occupational physical activity. This was investigated in a worksite randomized controlled trial (RCT) of aerobic exercise among cleaners.

METHODS

We randomized 116 cleaners between 18-65 years. The aerobic exercise group (N=57) performed worksite aerobic exercise (30 minutes twice a week) and the reference group (N=59) received lectures. Cardiorespiratory fitness, blood pressure (BP) and diurnal heart rate (HR) for measuring aerobic workload [% HR reserve (% HRR)] were collected at baseline and after four months. A repeated measure 2×2 multi-adjusted mixed-model design was applied to compare the between-group differences in an intention-to-treat analysis.

RESULTS

Between-group differences (P<0.01) were found: cardiorespiratory fitness 2.2 [standard error (SE) 0.8] ml O 2 × min -1 × kg -1 [95% confidence interval (95% CI) 0.6-3.8], aerobic workload - 3.5 (SE 1.2) % HRR (95% CI - 5.9- -1.0), resting HR -3.8 (SE 1.2) bpm (95 % CI -6.1- - 1.4), sleeping HR -3.8 (SE 1.1) bpm (95% CI - 5.9- - 1.7), and systolic BP 3.6 (SE 1.3) mmHg (95% CI 1.1-6.0).

CONCLUSIONS

Worksite aerobic exercise seems to improve cardiorespiratory fitness, aerobic workload, and resting and sleeping HR, but increase systolic BP among cleaners. Beneficial physiological cardiovascular effects are seen from aerobic exercise, but also a harmful effect is evident. Therefore, recommendations should take into consideration the potential cardiovascular overload from additional aerobic exercise on workers with high levels of occupational physical activity.

Wage theft as a neglected public health problem: an overview and case study from San Francisco's Chinatown District

Wage theft, or nonpayment of wages to which workers are legally entitled, is a major contributor to low income, which in turn has adverse health effects. We describe a participatory research study of wage theft among immigrant Chinatown restaurant workers. We conducted surveys of 433 workers, and developed and used a health department observational tool in 106 restaurants. Close to 60% of workers reported 1 or more forms of wage theft (e.g., receiving less than minimum wage [50%], no overtime pay [> 65%], and pay deductions when sick [42%]). Almost two thirds of restaurants lacked required minimum wage law signage. We discuss the dissemination and use of findings to help secure and enforce a wage theft ordinance, along with implications for practice.

Job stress and work-related musculoskeletal symptoms among intensive care unit nurses: a comparison between job demand-control and effort-reward imbalance models

BACKGROUND

The aims of this study were to compare job demand-control (JDC) and effort-reward imbalance (ERI) models in examining the association of job stress with work-related musculoskeletal symptoms and to evaluate the utility of a combined model.

METHODS

This study analyzed cross-sectional survey data obtained from a nationwide random sample of 304 intensive-care unit (ICU) nurses. Demographic and job factors were controlled in the analyses using logistic regression.

RESULTS

Both JDC and ERI variables had strong and statistically significant associations with work-related musculoskeletal symptoms. Effort-reward imbalance had stronger associations than job strain or iso-strain with musculoskeletal symptoms. Effort-reward imbalance alone showed similar or stronger associations with musculoskeletal symptoms compared to combined variables of the JDC and ERI models.

CONCLUSIONS

The ERI model appears to capture the magnitude of the musculoskeletal health risk among nurses associated with job stress at least as well and possibly better than the JDC model. Our findings suggest that combining the two models provides little gain compared to using effort-reward imbalance only.

Promoting health and safety in San Francisco's Chinatown restaurants: findings and lessons learned from a pilot observational checklist

Noncompliance with labor and occupational health and safety laws contributes to economic and health inequities. Environmental health agencies are well positioned to monitor workplace conditions in many industries and support enhanced enforcement by responsible regulatory agencies. In collaboration with university and community partners, the San Francisco Department of Public Health used an observational checklist to assess preventable occupational injury hazards and compliance with employee notification requirements in 106 restaurants in San Francisco's Chinatown. Sixty-five percent of restaurants had not posted required minimum wage, paid sick leave, or workers' compensation notifications; 82% of restaurants lacked fully stocked first-aid kits; 52% lacked antislip mats; 37% lacked adequate ventilation; and 28% lacked adequate lighting. Supported by a larger community-based participatory research process, this pilot project helped to spur additional innovative health department collaborations to promote healthier workplaces.

Return-to-work self-efficacy: development and validation of a scale in claimants with musculoskeletal disorders

INTRODUCTION We report on the development and validation of a 10-item scale assessing self-efficacy within the return-to-work context, the Return-to-Work Self-Efficacy (RTWSE) scale. METHODS Lost-time claimants completed a telephone survey 1 month (n = 632) and 6 months (n = 446) after a work-related musculoskeletal injury. Exploratory (Varimax and Promax rotation) and confirmatory factor analyses of self-efficacy items were conducted with two separate subsamples at both time points. Construct validity was examined by comparing scale measurements and theoretically derived constructs, and the phase specificity of RTWSE was studied by examining changes in strength of relationships between the RTWSE Subscales and the other constructs at both time measures. RESULTS Factor analyses supported three underlying factors: (1) Obtaining help from supervisor, (2) Coping with pain (3) Obtaining help from co-workers. Internal consistency (alpha) for the three subscales ranged from 0.66 to 0.93. The total variance explained was 68% at 1-month follow-up and 76% at 6-month follow-up. Confirmatory factor analyses had satisfactory fit indices to confirm the initial model. With regard to construct validity: relationships of RTWSE with depressive symptoms, fear-avoidance, pain, and general health, were generally in the hypothesized direction. However, the hypothesis that less advanced stages of change on the Readiness for RTW scale would be associated with lower RTWSE could not be completely confirmed: on all RTWSE subscales, RTWSE decreased significantly for a subset of participants who started working again. Moreover, only Pain RTWSE was significantly associated with RTW status and duration of work disability. With regard to the phase specificity, the strength of association between RTWSE and other constructs was stronger at 6 months post-injury compared to 1 month post-injury. CONCLUSIONS A final 10-item version of the RTWSE has adequate internal consistency and validity to assess the confidence of injured workers to obtain help from supervisor and co-workers and to cope with pain. With regard to phase specificity, stronger associations between RTWSE and other constructs at 6-month follow-up suggest that the association between these psychological constructs consolidates over time after the disruptive event of the injury.

1st place, PREMUS best paper competition: workplace and individual factors in wrist tendinosis among blue-collar workers--the San Francisco study

OBJECTIVE

Workplace studies have linked hand/wrist tendinosis to forceful and repetitive hand exertions, but the associations are not consistent. We report findings from a prospective study of right wrist tendinosis among blue-collar workers.

METHODS

Workers (N=413) at four industries were followed for 28 months with questionnaires and physical examinations every 4 months to identify incident cases of right wrist tendinosis. Exposure assessment of force and repetition were based on field measurements and video analysis to determine repetition rate and the percent time (% time) in heavy pinch (>1 kg-force) or power grip (>4 kg-force). All exposure variables were measured at the level of the individual and task. For workers responsible for >1 task, a time-weighted average exposure was calculated based on task hours per week. A proportional hazards model was used to assess the relationship between exposures and incidence of wrist tendinosis.

RESULTS

During the 481 person-years of follow-up, there were 26 incident cases of right wrist tendinosis [incidence rate (IR) 5.40 cases per 100 person-years]. Adjusting for age, gender, and repetition, wrist tendinosis was associated with % time spent in heavy pinch [hazard ratio (HR) 5.01, 95% CI 1.27-19.79). Composite exposure measure American Conference of Industrial Hygienists Threshold Limit Value (ACGIH-TLV) for hand activity level (HR 3.95, 95% CI 1.52-10.26) was also associated with the outcome for the medium-exposure group using video-based total repetition rate.

CONCLUSIONS

The workplace factors predicting wrist tendinosis were time-weighted average values of % time spent in heavy pinch and the ACGIH-TLV for Hand Activity Level. The % time spent in power grip was not a significant predictor, nor were any measures of repetition. An exposure-response relationship was observed for the % time spent in heavy pinch. These findings may improve programs for preventing occupational wrist tendinosis.

Disparities by ethnicity, language, and immigrant status in occupational health experiences among Las Vegas hotel room cleaners

OBJECTIVE

We examined disparities in workers' occupational health experiences.

METHODS

We surveyed 941 unionized Las Vegas hotel room cleaners about their experiences with work-related pain and with employers, physicians, and workers' compensation. Data were analyzed for all workers and by ethnicity, language, and immigrant status.

RESULTS

Hispanic and English as second language (ESL) workers were more likely than their counterparts to report work-related pain and, along with immigrant workers, to miss work because of this pain. Hispanic, ESL, and immigrant workers were not consistently at a disadvantage with regard to their own responses to work-related pain but were so with respect to reported responses by workers' compensation, physicians, and employers.

CONCLUSIONS

There are indications of disparities in occupational health experiences within this job title. The use of different group classifications, while implying different mechanisms, produced similar results.

Factors associated with safe patient handling behaviors among critical care nurses

BACKGROUND

Patient handling is a major risk factor for musculoskeletal (MS) injury among nurses. The aims of the study were to describe nurses' work behaviors related to safe patient handling and identify factors influencing their safe work behaviors, including the use of lifting equipment.

METHODS

A cross-sectional study using a mailed questionnaire with a nationwide random sample of 361 critical care nurses. Nurses reported on the physical, psychosocial, and organizational characteristics of their jobs and on their MS symptoms, risk perception, work behaviors, and demographics. Hierarchical multiple linear regression analyses were used to identify significant factors.

RESULTS

More than half of participants had no lifting equipment on their unit, and 74% reported that they performed all patient lift or transfer tasks manually. Significant factors for safer work behavior included better safety climate, higher effort-reward imbalance, less overcommitment, greater social support, and day shift work. Physical workload, personal risk perception, or MS symptom experiences were not associated with safe work behavior.

CONCLUSIONS

Safe work behaviors are best understood as socio-cultural phenomena influenced by organizational, psychosocial, and job factors but, counter to extant theories of health behaviors, do not appear to be related to personal risk perception. Management efforts to improve working conditions and enhance safety culture in hospitals could prove to be crucial in promoting nurses' safe work behavior and reducing risk of MS injury.

Psychosocial work factors and shoulder pain in hotel room cleaners

BACKGROUND

Hotel room cleaners have physically demanding jobs that place them at high risk for shoulder pain. Psychosocial work factors may also play a role in shoulder pain, but their independent role has not been studied in this group.

METHODS

Seventy-four percent (941 of 1,276) of hotel room cleaners from five Las Vegas hotels completed a 29-page survey assessing health status, working conditions, and psychosocial work factors. For this study, 493 of the 941 (52%) with complete data for 21 variables were included in multivariate logistic regression analyses.

RESULTS

Fifty-six percent reported shoulder pain in the prior four weeks. Room cleaners with effort-reward imbalance (ERI) were three times as likely to report shoulder pain (OR 2.99, 95% CI 1.95-4.59, P = 0.000) even after adjustment for physical workload and other factors. After adjustment for physical workload, job strain and iso-strain were not significantly associated with shoulder pain.

CONCLUSIONS

ERI is independently associated with shoulder pain in hotel room cleaners even after adjustment for physical workload and other risk factors.

Effort-reward imbalance at work and self-rated health of Las Vegas hotel room cleaners

BACKGROUND

This study investigates the relationship between effort-reward-imbalance (ERI) at work and self-rated health (SF-36) among 941 Las Vegas hotel room cleaners (99% female, 84% immigrant).

METHODS

Logistic regression models adjust for age, health behaviors, physical workload and other potential confounders.

RESULTS

50% reported ERI and 60% poor or fair general health. Significant associations were found between ERI and all SF-36 health measures. Workers in the upper quartile of the efforts/rewards ratio were 2-5 times more likely to experience poor or fair general health, low physical function, high levels of pain, fatigue, and role limitations due to physical and mental health problems.

CONCLUSIONS

The cross-sectional design limits causal interpretation of these associations. However, the development of interventions to reduce ERI and to improve general health among room cleaners deserves high priority considering that both high ERI and low self-rated health have predicted chronic diseases and mortality in prospective studies.

Using community-based participatory research to design and initiate a study on immigrant worker health and safety in San Francisco's Chinatown restaurants

BACKGROUND

Restaurant workers have among the highest rates of work-related illness and injury in the US, but little is known about the working conditions and occupational health status of Chinese immigrant restaurant workers.

METHODS

Community-based participatory research (CBPR) was employed to study restaurant working conditions and worker health in San Francisco's Chinatown. A community/academic/health department collaborative was formed and 23 restaurant workers trained on research techniques and worker health and safety. A worker survey instrument and a restaurant observational checklist were collaboratively developed. The checklist was piloted in 71 Chinatown restaurants, and the questionnaire administered to 433 restaurant workers.

RESULTS

Restaurant workers, together with other partners, made substantial contributions to construction of the survey and checklist tools and improved their cultural appropriateness. The utility of the checklist tool for restaurant-level data collection was demonstrated.

CONCLUSIONS

CBPR holds promise for both studying worker health and safety among immigrant Chinese restaurant workers and developing culturally appropriate research tools. A new observational checklist also has potential for restaurant-level data collection on worker health and safety conditions.