Work-Related Biomechanical Exposure and Job Strain as Separate and Joint Predictors of Musculoskeletal Diseases: A 28-Year Prospective Follow-up Study

Workplace Psychosocial Factors and Their Association With Musculoskeletal Disorders: A Systematic Review of Longitudinal Studies

This systematic review examines literature regarding the relationship between workplace psychosocial factors and musculoskeletal disorders (MSDs). Musculoskeletal disorders are the leading cause of work disability, resulting in billions of dollars of financial losses. Evidence suggests that workplace psychosocial factors can lead to the development and progression of MSDs. A data search was conducted in MEDLINE, EMBASE, PsychINFO, Scopus, and CINAHL (Cumulative Index to Nursing and Allied Health Literature) from August 2009 to May 2020 inclusive. Other eligibility criteria included studies published in English, conducted on adults within a workplace setting, conducted in developed economies, and were stability-control longitudinal observational studies. Studies were independently screened for eligibility, using COVIDENCE (software for managing and streamlining systematic reviews) and assessed for quality by multiple authors, using the JBI Evidence synthesis tool. From 6,812 studies, 47 articles were included in the final analysis. The most common MSDs investigated were lower back pain, neck and shoulder pain, and upper extremity symptoms and disorders. Included articles identified that psychosocial workplace factors of support, collaboration, job control, and job demands were statistically significantly associated with risk and progression of MSDs. Review of the articles included in this article supports the theory that MSDs have a multifactorial, complex etiology that includes psychosocial factors. Interventions to enhance psychosocial work environment provide opportunities to reduce the risk of MSDs.

Psychosocial working conditions and cognitive and physical impairment in older age

BACKGROUND

Psychosocial working conditions are associated with cognitive and physical impairments. The aim of this study was to investigate the associations between mid-late life psychosocial working conditions and the combination of physical and cognitive impairment among older adults, and the potential sex differences in these associations.

METHODS

Data were derived from two Swedish nationally representative surveys (n = 839; follow-up: 20-24 years). Multinomial and binary logistic regressions assessed the associations between work stressors (job demand-control model), and a combination of cognitive and physical impairment.

RESULTS

Low control jobs were significantly associated with higher odds of cognitive (OR: 1.41, CI: 1.15-1.72) and physical impairment (OR: 1.23, CI: 1.02-1.47), and cognitive and physical impairment combined (OR: 1.50, CI: 1.19-1.89). Passive jobs (low control, low demand) were associated with higher odds of cognitive impairment (OR: 1.57, CI: 1.12-2.20), and combined cognitive and physical impairment (OR: 1.59, CI: 1.07-2.36). Active jobs (high control, high demand) were associated with lower odds of cognitive impairment (OR: 0.48, CI: 0.29-0.80). Sex-stratified analyses showed stronger associations among men; passive jobs were associated with both cognitive (OR: 2.18, CI: 1.31-3.63) and physical impairment (OR: 1.78, CI: 1.13-2.81), while low strain jobs were associated with less physical impairment (OR: 0.55, CI: 0.33-0.89). No significant associations between work stressors and impairment were found for women.

CONCLUSIONS

These results highlight the importance of psychosocial working conditions for late-life physical and cognitive impairment, especially among men. Jobs characterised by low control and low demands are associated with higher risk for impairments.

Interaction between physical demands and job strain on musculoskeletal symptoms and work performance

This study investigated the interaction between physical demands and job strain on musculoskeletal symptoms in upper extremities (MSUE) and work performance. Two years of prospective data were analysed from 713 full-time workers from twelve manufacturing and healthcare facilities in Washington in the United States. Physical exposure was measured by the Strain Index and Threshold Limit Value for hand activity, giving rise to safe, action, and hazardous physical demand groups. Job strain was calculated as the ratio of psychological job demands to job control. Multilevel modelling analysis showed that job strain affected MSUE and limited work performance less in the high physical demand group than the safe group because the protective effect of job control was smaller in these groups. Findings may suggest that high physical demand jobs are structured such that workers have low job control or high physical demand groups experience job strain not adequately captured by psychosocial variables.Practitioner Summary: The effects of job strain and job control on musculoskeletal symptoms in upper extremities and work performance were smaller among workers with higher physical demands. This could imply that high physical demand jobs limit job control or psychosocial variables may not adequately capture job strain among high physical demand groups.

Differences between men and women in their risk of work injury and disability: A systematic review

Background

Health responses associated with occupational exposures can vary between men and women.

Aims

This study reviewed the work injury and disability risks associated with similar types of occupational exposures for men and women within and across occupations.

Materials & Methods

A systematic review was undertaken of observational studies published between 2009 and 2019. Studies were required to empirically compare men and women for associations between occupational exposures and work injury or disability outcomes. Included studies were appraised for methodological quality and medium to high rated studies were compared for risk differences between men and women.

Results

Of 14,006 records identified, 440 articles were assessed for methodological quality, and 33 medium to high rated studies were included and reviewed. Among all occupations, the association between physical exposures, job demands, noise, and repetitive tasks, and injury risk were stronger among men. The relationship between repetitive tasks and sickness absence was stronger among women. Most studies examining psychological exposures found no risk differences for men and women across occupations. Men were at higher injury risk in certain occupations in primary and secondary industry sectors involving physical exposures and some chemical/biological exposures. Women were at higher injury risk for the physical demands and repetitive tasks of health care and aluminum production occupations.

Conclusion

This review found that men and women can have different work injury and disability risks, both across and within the same occupations, for some physical exposures and to a lesser extent for some chemical and biological exposures. These differences might be a result of occupation‐specific task differences.

A systematic overview on the risk effects of psychosocial work characteristics on musculoskeletal disorders, absenteeism, and workplace accidents

The present article provides a systematic overview on the relationship between psychosocial work characteristics and musculoskeletal disorders, absenteeism, and workplace accidents. The study identified and reviewed the findings of 24 systematic reviews or meta-analysis and 6 longitudinal studies. Publications were systematically searched in several databases from 1966 to January 2021. To summarize the level of evidence, a best evidence synthesis was performed, and the quality of included studies was rated. High job demands, high job strain, high effort/reward-imbalance and low social support showed a strong evidence to increase the risk for musculoskeletal disorders. In addition to job demands and job strain, low perceived fairness proved to be a risk factor of absenteeism with strong evidence. Due to the small number of studies, no reliable evidence assessment for workplace accidents was possible. The summarized findings can improve risk assessment methods, by providing a systematic estimation of the potential risk severity of psychosocial work characteristics and assist practitioners in further developing the psychosocial risk assessment.

Psychosocial Working Conditions and Social Participation. A 10-Year Follow-Up of Senior Workers

Social participation is important for health, and it is well known that high strain jobs impact negatively on mental and physical health. However, knowledge about the impact of psychosocial working conditions on social participation from a long-term perspective is lacking. The purpose of this study was to investigate the associations between different job types and social participation from a long-term perspective. A comprehensive public health questionnaire "The Scania Public Health Survey", was used, and psychosocial working conditions were measured with a Swedish translation of the Job Content Questionnaire. Based on data from 1098 working respondents aged 55 at baseline and a 10-year follow-up when the respondents were not working, the analyses revealed that social participation varied by job type. Jobs with high decision latitude, as in active and relaxed jobs, seem to predict high social participation, even after cessation of employment. Besides that, the result suggests that high social participation during working life is a predictor of high social participation from a long-term perspective which promotes healthy aging. Incentives for working longer are strongly related to good working conditions. A supportive work environment with possibilities for employees to participate in decision making, i.e., high control, is vital for a sustainable working life. This may contribute to an extended working life and may also support social participation prior to retirement as well as after retirement and thus to healthy aging.

Multisite musculoskeletal pain trajectories from midlife to old age: a 28-year follow-up of municipal employees

OBJECTIVES

We studied the developmental trajectories of multisite musculoskeletal pain (MSP) to learn whether pain in midlife persists to old age, and whether pain trajectories associate with midlife work or lifestyle exposures or retirement from work.

METHODS

Municipal employees aged 44-58 years were studied in 1981 (n=6257) with follow-ups in 1985, 1992, 1997 and 2009. Pain in the neck, low back, and upper and lower limbs was assessed in each survey. Trajectories of the number (0-4) of pain sites were defined using growth mixture modelling (n=3093). Workload, lifestyle and morbidity were elicited by questionnaire and retirement from registries. Associations of baseline factors with pain trajectories were assessed by multinomial logistic regression. Cumulative hazard curves for retirement by trajectory group were calculated.

RESULTS

Three trajectories of pain over 28 years emerged: low (25%), moderate (52%) and high-decreasing (23%). In the latter, the number of pain sites first decreased sharply, stabilising to a moderate level after most subjects had retired. The disability pension rate was highest in this trajectory, which associated with high baseline morbidity, particularly musculoskeletal disorder (OR 8.06; 95% CI 5.97 to 10.87). Also high biomechanical exposure (2.86;95% CI 2.16 to 3.78), high job demands (1.79; 95% CI 1.39 to 2.30), high job control (OR 0.70; 95% CI 0.54 to 0.90), body mass index (BMI) ≥25.0 kg/m² (1.40; 95% CI 1.09 to 1.80) and low leisure-time physical activity (LTPA) (1.39; 95% CI 1.09 to 1.78) at baseline were associated with this trajectory. However, high LTPA and BMI in repeated surveys also associated with the high-decreasing trajectory.

CONCLUSION

MSP in midlife often persists to old age. However, high widespreadness of pain may decrease with retirement from work.

Occupational class and risk of renal cell cancer

OBJECTIVES

We sought to examine the association between occupational class linked to job stress and the risk of renal cell cancer. To identify potential mediators, we additionally examined whether any observed associations persisted even after controlling for the contribution of stress-related factors (eg, smoking, hypertension, and obesity).

METHODS

Using nationwide inpatient records (1984 to 2016) from the Rosai Hospital group in Japan, we identified 3316 cases of renal cell cancer (excluding upper tract urothelial cancer) and 168 418 controls. We classified patients' occupational class (blue-collar workers, service workers, professionals, and managers) and cross-classified it by industry type (blue-collar, service, and white-collar) based on a standardized national classification. Unconditional logistic regression with multiple imputation was used for the analyses.

RESULTS

A significantly elevated risk of renal cell cancer was found among men in higher occupational class (eg, professionals and managers). The elevated odds in male managers across all industries persisted even after controlling for smoking and alcohol consumption, with the association being more pronounced in blue-collar industries (OR, 1.61; 95% CI, 1.34-1.93). The association appeared to be mainly mediated by hypertension.

CONCLUSION

Occupational class is associated with the risk of renal cell cancer in men, particularly through modifiable risk factors.