Long-term sickness absence from combined factors related to physical work demands: prospective cohort study

Does the distribution of musculoskeletal pain shape the fate of long-term sick leave? A prospective cohort study with register follow-up

ABSTRACT

Although multisite pain can markedly reduce work ability, the relevance of the bodily pain distribution as a predictor of long-term sick leave is still unknown. This study aimed to investigate the association between musculoskeletal pain distributions and long-term sick leave in the general working population of Denmark and included 66,177 currently employed wage earners without long-term sick leave during the prior 52 weeks. Participants reported whether they had pain in the lower extremity (hips/knees), upper extremity (neck/shoulders), or the low back. The analysis controlled for age, sex, year of survey reply, educational level, occupational group, psychosocial work factors, body max index, smoking, leisure-time physical activity, and mental health confounders. The results demonstrated that the risk of long-term sick leave increased with the number of pain sites. Compared with no pain, localized pain in any body region increased the risk/hazard by 25% to 29% (HR [95% CI]: 1.29 [1.07-1.54] for pain only in the low back), whereas pain in 2 regions increased the risk by 39% to 44% (HR [95% CI]: 1.41 [1.18-1.69] for pain in the low back + hips/knees). Workers reporting pain in all 3 regions experienced a 72% increased risk (HR [95% CI]: 1.72 [1.55-1.91]). Thus, the number of pain regions seems to matter more than the exact pain location. The spatial extension of musculoskeletal pain in workers functions as a gradient system, where pain spread throughout the body is an independent indicator of the high risk of long-term sick leave.

Artificial Intelligence and Occupational Health and Safety, Benefits and Drawbacks

This paper discusses the impact of artificial intelligence (AI) on occupational health and safety. Although the integration of AI into the field of occupational health and safety is still in its early stages, it has numerous applications in the workplace. Some of these applications offer numerous benefits for the health and safety of workers, such as continuous monitoring of workers' health and safety and the workplace environment through wearable devices and sensors. However, AI might have negative impacts in the workplace, such as ethical worries and data privacy concerns. To maximize the benefits and minimize the drawbacks of AI in the workplace, certain measures should be applied, such as training for both employers and employees and setting policies and guidelines regulating the integration of AI in the workplace.

Comprehensive evaluation of the impact of workplace exposures on physician-certified sick leave in the general working population

BACKGROUND

Our objective was to quantify the prospective associations between work factors across chemical, physical, mechanical, and psychosocial domains and the onset of medically certified sick leave.

METHODS

Eligible respondents were interviewed in 2009, 2013, or 2016 and were registered in the national sick leave register with an employee relationship lasting more than 50 working days during the year of the survey interviews and the following year (n = 15,294 observations). To focus on the onset of high-level sick leave (HLSL; >16 days a year), we excluded individuals with HLSL during the survey year (baseline). We then used mixed-effect logistic regression models to assess prospective associations between self-reported work conditions and the occurrence of doctor-certified HLSL in the following year.

RESULTS

The average occurrence of HLSL was 13.1%. After adjusting for sex, age, level of education, chronic health problems, and smoking, we observed an exposure-response relationship between cumulative exposure to work factors within all domains and the occurrence of HLSL. When evaluating the impact of combined exposures, predicted odds ratios (OR) for employees exposed to 1, 2, and 3 or more work factors within all domains were 1.60 (95%CI 1.32 - 1.94), 2.56 (95%CI 1.73 - 3.74) and 4.09 (95%CI 2.28 - 7.25), compared to those not exposed.

CONCLUSIONS

The results support the notion that exposure to multiple work factors in various domains, including psychosocial, mechanical, chemical, and physical work conditions, is associated with an increased risk of high-level sick leave. Employers and occupational health professionals should consider the joint impact of these domains when designing interventions.

Prospective associations of psychosocial work factors with sickness absence spells and duration: Results from the French national working conditions survey

BACKGROUND

Some psychosocial work factors are associated with sickness absence, however little information is available on the associations of various psychosocial work factors and multiple exposures with sickness absence spells and duration, and gender differences.

METHODS

Data were from the French working conditions survey conducted on a nationally representative sample of the working population. The study sample included 17,437 employees (7292 men, 10,145 women) followed from 2013 to 2016 and/or from 2016 to 2019. Occupational exposures (20 psychosocial work factors, 4 working time/hours factors, 4 physical work exposures) were measured at the beginning of each follow-up period. Hurdle and multinomial models were used to study the associations with the number of days and spells of sickness absence.

RESULTS

Most of the psychosocial work factors predicted the risk of at least 1 day of sickness absence. Stronger associations were found among women than men for some factors. Psychosocial work factors were more likely to predict the number of spells than the number of days of sickness absence. Some physical work exposures predicted sickness absence spells and days, whereas shift work in women predicted the risk of at least 1 day of sickness absence. Dose-response associations were found between multiple psychosocial work exposures and sickness absence spells, and between multiple physical exposures and sickness absence spells and days.

CONCLUSION

Comprehensive prevention policies oriented toward the whole psychosocial and physical work environment should be useful to reduce sickness absence among men and women.

The Joint Contributions of Overweight/Obesity and Physical and Mental Working Conditions to Short and Long Sickness Absence among Young and Midlife Finnish Employees: A Register-Linked Follow-Up Study

INTRODUCTION

Overweight/obesity and strenuous working conditions are associated with work disability, but their joint contributions to sickness absence (SA) are unknown. We aimed to examine their joint contributions to SA periods of 1-7 and ≥8 days.

METHODS

Self-reported data on body mass index and working conditions, including perceived physically and mentally strenuous work and hours per day spent in heavy physical work, were linked to the employer's SA register for the City of Helsinki, Finland, employees (n = 4,323, women 78%) who were 19-39 years old at baseline. We calculated rate ratios (RRs) and 95% confidence intervals (CIs) for SA periods using negative binomial regression models among participants with healthy weight and overweight/obesity, with and without exposure to strenuous working conditions. The mean follow-up time was 2.1 years.

RESULTS

Participants with overweight/obesity and exposure to physically strenuous working conditions had the highest age- and gender-adjusted RRs for SA periods of both 1-7 and ≥8 days (physically strenuous work: RR: 1.38, CI: 1.25-1.52, and RR: 1.87, CI: 1.60-2.18, respectively; ≥3 h per day spent in physical work: RR: 1.40, CI: 1.26-1.55 and 2.04, CI: 1.73-2.40, respectively). The interaction between overweight/obesity and physically strenuous working conditions was additive for SA periods of 1-7 days and weakly synergistic for SA periods of ≥8 days. For mentally strenuous work, participants with overweight/obesity and exposure to mentally strenuous work had the highest age-adjusted RRs for SA periods of ≥8 days, and the interaction was additive.

CONCLUSION

The joint contributions of overweight/obesity and exposure to strenuous working conditions to SA should be considered when aiming to reduce employees' SA. Employers might benefit from providing employees adequate support for weight management and adherence to healthy lifestyles while improving employees' working conditions.

Musculoskeletal pain intensity and risk of long-term sickness absence in the general working population: A prospective cohort study with register follow-up

Determining predictors of sickness absence could allow for better screening, guidance, and development of preventive efforts aimed at those in increased risk. This study aimed to determine the prospective association between musculoskeletal pain intensity and risk of incident register-based long-term sickness absence in the general working population, as well as to determine the population attributable fraction. Drawing on data from a nation-wide questionnaire survey, this prospective cohort study followed a representative sample of the Danish general working population without recent long-term sickness absence (≥6 consecutive weeks) (n = 69,273) for long-term sickness absence up to two years (mean follow-up: 93 weeks) in a national register. The predictor was musculoskeletal pain intensity in the neck/shoulder and low-back during the preceding three months rated on an 11-point numerical rating scale from 0 to 10. The weighted incidence of long-term sickness-absence was 8.9% during two-year follow-up (n = 6165). We observed a clear dose-response association between musculoskeletal pain intensity of the neck/shoulder or low-back and the risk of incident long-term sickness absence, with a lower threshold of increased risk of 4 and 3 (scale 0-10) for neck/shoulder (HR (95% CI): 1.25 (1.09-1.42)) and low-back pain (HR (95% CI): 1.13 (1.00-1.29)), respectively. Prevention of pain intensities at or above 4 out of 10 could potentially prevent 17% (population attributable fraction, PAF (95% CI): 16.8 (13.6-20.1)) of the total long-term sickness absence in the general working population. Large-scale interventions to prevent and manage musculoskeletal pain need to be documented and implemented.

Separate and joint associations of chronic pain, multisite pain and mental health with sickness absence among younger employees: a register based longitudinal study

BACKGROUND

Pain conditions and poorer mental health are associated with work disability. However, few studies have examined the association of concurrent pain and poorer mental health with sickness absence among younger employees. We examined separate and joint associations of chronic pain, multisite pain, and mental health with total and long-term all-cause sickness absence days among younger Finnish municipal employees.

METHODS

The Young Helsinki Health-study data were collected in 2017 from 19-39-year-old employees of the City of Helsinki, Finland. Chronic (≥ 3 months) and multisite (≥ 2 body sites) pain and mental health (RAND-36 emotional wellbeing subscale dichotomized by median score) were self-reported (n = 3911). Chronic pain, multisite pain and mental health were analyzed separately and combined. Register data on total (≥ 1 workdays) and long-term (≥ 11 workdays) sickness absence days during the following year were obtained. Negative binomial regression analyses were performed with sociodemographic, socioeconomic, and health-related factors as confounders. Gender interaction and synergistic indices were examined.

RESULTS

Chronic multisite pain was associated with long-term sickness absence days (rate ratio [RR] 2.51, 95% CI 1.17-5.42). Chronic pain (RR 5.04, 95% CI 2.14-11.87) and multisite pain (RR 4.88, 95% CI 2.30-10.33) were associated with long-term sickness absence days among employees with poorer mental health. There was a synergistic interaction between gender and multisite pain for total sickness absence days (synergy index 1.80, 95% CI 1.27-2.54), with stronger associations among women.

CONCLUSIONS

Chronic and multisite pain are associated with long-term sickness absence among younger employees, particularly among women and employees with concurrent poorer mental health. Consideration of this knowledge at workplaces and in healthcare could help to identify and support employees at increased risk of later sickness absence.

Utilizing a Nordic Crosswalk for Occupational Coding in an Analysis on Occupation-Specific Prolonged Sickness Absence among 7 Million Employees in Denmark, Finland, Norway and Sweden

We identified occupations with a high incidence of prolonged sickness absence (SA) in Nordic employees and explored similarities and differences between the countries. Utilizing data from national registers on 25-59-year-old wage-earners from Denmark, Finland, Norway and Sweden, we estimated the gender- and occupation-specific age-adjusted cumulative incidence of SA due to any cause, musculoskeletal diseases and mental disorders. To increase the comparability of occupations between the countries, we developed a Nordic crosswalk for occupational codes. We ranked occupational groups with the incidence of SA being statistically significantly higher than the population average of the country in question and calculated excess fractions with the employee population being the reference group. We observed considerable occupational differences in SA within and between the countries. Few occupational groups had a high incidence in all countries, particularly for mental disorders among men. In each country, manual occupations typically had a high incidence of SA due to any cause and musculoskeletal diseases, while service occupations had a high incidence due to mental disorders. Preventive measures targeted at specific occupational groups have a high potential to reduce work disability, especially due to musculoskeletal diseases. Particularly groups with excess SA in all Nordic countries could be at focus.

Does occupational forward bending of the back increase long-term sickness absence risk? A 4-year prospective register-based study using device-measured compositional data analysis

OBJECTIVE

Forward bending of the back is common in many jobs and a risk factor for sickness absence. However, this knowledge is based on self-reported forward bending that is generally imprecise. Thus, we aimed to investigate the dose-response relation between device-measured forward bending at work and prospective register-based risk of long-term sickness absence (LTSA).

METHODS

At baseline, 944 workers (93% from blue-collar jobs) wore accelerometers on their upper back and thigh over 1-6 workdays to measure worktime with forward bending (>30˚ and >60˚) and body positions. The first event of LTSA (≥6 consecutive weeks) over a 4-year follow-up were retrieved from a national register. Compositional Cox proportional hazard analyses were used to model the association between worktime with forward bending of the back in an upright body position and LTSA adjusted for age, sex, body mass index (BMI), occupational lifting/carrying, type of work, and, in an additional step, for leisure time physical activity (PA) on workdays.

RESULTS

During a mean worktime of 457 minutes/day, the workers on average spent 40 and 10 minutes on forward bending >30˚ and >60˚ in the upright position, respectively. Five more minutes forward bending >30˚ and >60˚ at work were associated with a 4% [95% confidence interval (CI) 1.01-1.07] and 8% (95% CI 1.01-1.16) higher LTSA risk, respectively. Adjustment for leisure-time PA did not influence the results.

CONCLUSION

We found a dose-response association between device-measured forward bending of the back and prospective LTSA risk. This knowledge can be integrated into available feasible methods to measure forward bending of the back for improved workplace risk assessment and prevention.

Combined psychosocial work factors and risk of long-term sickness absence in the general working population: Prospective cohort with register follow-up among 69 371 workers

OBJECTIVE

This study aimed to investigate the importance of combined psychosocial work factors for the risk of long-term sickness absence (LTSA).

METHODS

We followed 69 371 employees in the general working population (Work Environment and Health in Denmark study 2012-2018), without LTSA during the preceding year, for up to two years in the Danish Register for Evaluation of Marginalization. Using k-means cluster analyses and weighted Cox-regression controlling for age, gender, survey year, education, health-behaviors, and physical work demands, we determined the prospective association of 11 identified clusters - based on the combination of nine psychosocial work factors (recognition, quantitative demands, work pace, emotional demands, influence, justice, role clarity, role conflicts, and support from colleagues) - with the risk of LTSA.

RESULTS

During 124 045 person-years of follow-up, 6197 employees developed LTSA (weighted 8.5%). Using the cluster with the most favorable psychosocial scores as reference, clusters scoring poorly on several combined psychosocial factors had increased risk of LTSA. The cluster scoring poor on all nine psychosocial factors exhibited the highest risk [hazard ratio (HR) 1.68, 95% confidence interval (CI) 1.45-1.94]. Scoring poorly on one or two psychosocial factors did not increase the risk of LTSA when combined with favorable scores on the other psychosocial factors. Interaction analyses showed that gender, but not age and education, modified the association between cluster and LTSA.

CONCLUSION

Scoring poorly on several combined psychosocial work factors plays an important role in the risk of LTSA. Scoring favorably on several psychosocial factors outweighed the potentially adverse effects of scoring poorly on one or two factors.

Work environment and labour market participation in early adulthood

BACKGROUND

Investigating whether a poor physical or psychosocial work environment is associated with low labour market participation in early adulthood is important to avoid negative health-related consequences and to improve job prospects.

AIMS

To investigate associations between the physical or psychosocial work environment and labour market participation in early adulthood.

METHODS

The study was based on data from the West Jutland Cohort, an ongoing study of individuals born in 1989 who lived in the western part of Jutland, Denmark, in 2004. Participants were employed individuals who had questionnaire data on their work environment at age 28 and register information on labour market participation at ages 28-29 (n = 1312). The outcome was categorized into low (>4 weeks) versus high (≤4 weeks) labour market participation based on the total number of weeks receiving any unemployment or health-related benefits during a 52-week period. Logistic regression analyses were performed to examine associations between work environment factors and labour market participation, taking confounders into account.

RESULTS

Low influence, low quality of leadership, high job insecurity and temporary employment were associated with low labour market participation. High job insecurity (OR: 2.2; 95% CI 1.5-3.1) and temporary employment (OR: 3.1; 95% CI 2.1-4.5) were strongly associated with low labour market participation. An association was seen between hard physical work and low labour market participation.

CONCLUSIONS

Several physical and psychosocial work environment factors, especially high job insecurity and temporary employment, have a negative impact on labour market participation in early adulthood.

The Importance of Lifting Height and Load Mass for Muscular Workload during Supermarket Stocking: Cross-Sectional Field Study

High physical work demands increase the risk of musculoskeletal disorders and sickness absence. Supermarket work involves a high amount of manual material handling. Identifying specific ergonomic risk factors is an important part of occupational health and safety efforts in the supermarket sector. In this cross-sectional field study among 64 supermarket workers, we used electromyography during the workday to determine the influence of lifting height and load mass on muscular workload of the low-back and neck/shoulder muscles during un-restricted manual material handling (grocery stocking). We found a significant effect of load mass, i.e., higher loads associated with higher muscular workload in the low-back and neck/shoulder muscles. We demonstrated a significant interaction between start and end position, i.e., lifts performed from 'Low' start positions to 'High' end positions demonstrated the highest low-back muscular workload, whereas 'High' positions were associated with increased neck/shoulder workload. In conclusion, lifting higher loads and lifting goods from low to high positions (low-back) and at high positions (neck/shoulder) are associated with higher muscular workload. These results can be used to guide highly warranted preventive initiatives to reduce the physical workload during supermarket work.

Potential of micro-exercise to prevent long-term sickness absence in the general working population: prospective cohort study with register follow-up

This study assesses the potential of workplace-based micro-exercise (brief and simple exercise bouts) to prevent long-term sickness absence (LTSA) at the population level. In the Work Environment and Health in Denmark Study (2012–2018), we followed 70,130 workers from the general working population, without prior LTSA, for two years in the Danish Register for Evaluation of Marginalisation. We used Cox regression with model-assisted weights and controlled for various confounders. From 2012 to 2018, the percentage of workers in Denmark using workplace-based micro-exercise during and outside of working hours increased from 7.1 to 10.9% and from 0.8 to 1.4%, respectively. The incidence of long-term sickness absence (at least 30 days) was 8.4% during follow-up. The fully adjusted model showed reduced risk of long-term sickness absence from using micro-exercise during working hours, (HR 0.86, 95% CI 0.77–0.96), but not when used outside of working hours. If used by all workers, micro-exercise during working hours could potentially prevent 12.8% of incident long-term sickness absence cases (population attributable fraction). In conclusion, micro-exercise performed during working hours holds certain potential to prevent incident long-term sickness absence in the general working population. Large-scale implementation of workplace-based micro-exercise may represent an unexploited opportunity for public health promotion.

Technical field measurements of muscular workload during stocking activities in supermarkets: cross-sectional study

Multiple studies have reported high prevalence of musculoskeletal disorders among supermarket workers. Technical field measurements can provide important knowledge about ergonomic risk factors for musculoskeletal disorders in the physical working environment, but these measurements are lacking in the supermarket sector. Therefore, using wearable electromyography and synchronous video recording in 75 supermarket workers, this cross-sectional study measured muscular workload during stocking activities in six different types of general store departments and during the thirteen most common work tasks across five different supermarket chains. Our results showed that muscular workload varies, especially for the low-back muscles, across (1) supermarket chains, (2) departments, and (3) specific stocking activities. Highest workloads of the low-back and neck/shoulders were seen in the fruit and vegetables department and during heavy, two-handed lifts of parcels (especially without using technical aids). In conclusion, physical work demands during supermarket stocking activities differ between chains, departments, and work tasks. These results can be used by company representatives and work environment professionals to specifically address and organize the stocking procedures to reduce the muscular workload during supermarket stocking.

Metabolic syndrome and the increased risk of medically-certified long-term sickness absence: a prospective analysis among Japanese workers

BACKGROUND

Metabolic syndrome (MetS) has been associated with various chronic diseases which may lead to long-term sickness absence (LTSA), but there is lacking information on the direct association between MetS and LTSA. The present study aimed to investigate the all-cause and cause-specific associations between MetS and the risk of medically-certified LTSA among Japanese workers.

METHOD

We recruited 67,403 workers (57,276 men and 10,127 women), aged 20-59 years, of 13 companies in Japan, during their health check-ups in 2011 (11 companies) and 2014 (2 companies), and followed them up for LTSA events (≥ 30 consecutive days) until March 31, 2020. MetS was defined according to the Joint Interim Statement. A Cox proportional hazards regression model was used to estimate hazard ratio (HR) and its 95% confidence interval (CI) for LTSA associated with MetS and its components.

RESULTS

During 408,324 person-years of follow-up, 2,915 workers experienced LTSA. The adjusted HR for all-cause LTSA was 1.54 (95% CI, 1.41-1.68) among those with vs without MetS. In cause-specific analysis, HRs associated with MetS significantly increased for LTSA due to overall physical disorders (1.76), cardiovascular diseases (3.16), diseases of the musculoskeletal system and connective tissue (2.01), cancers (1.24), obesity-related cancers (1.35), mental, behavioral and neurodevelopmental disorders (1.28), reaction to severe stress and adjustment disorders (1.46) and external causes (1.46). The number of MetS components were also significantly associated with increased LTSA risk.

CONCLUSION

MetS was associated with an increase in the risk of LTSA due to various diseases among Japanese workers.

Engaging Occupational Safety and Health Professionals in Bridging Research and Practice: Evaluation of a Participatory Workshop Program in the Danish Construction Industry

Engaging occupational safety and health (OSH) professionals has scarcely been evaluated as a means for transferring knowledge to practice about physical workload in the construction industry. The aim of this work was to examine how participants used and incorporate research-based knowledge from a three-day training course into practice. Twenty OSH professionals from the Danish construction industry participated in a workshop-training course. Researchers presented new knowledge and results about physically demanding work. The participants selected which themes they wanted to work with and developed an action plan. Evaluation was done using surveys and phone interviews. Analysis was based on how the OSH-professionals describe themselves, organizations, and the construction industry. Participant’s average scores on the level of implementation of their chosen action plans were 3 (on a response scale from 1–5, where 1 is ‘to a very low degree’ and 5 is ‘to a very high degree’) immediately after the workshop program and 2.5 at follow-up. Qualitative evaluations showed that actions had been initiated, and some progress had been made. The participants were satisfied with the workshop course and the possibility to increase their knowledge through inputs from researchers and colleges and strongly believe that they would succeed with implementing their action plans in the future.

High physical work demands have worse consequences for older workers: prospective study of long-term sickness absence among 69 117 employees

Objective

This study investigates the role of age for the prospective association between physical work demands and long-term sickness absence (LTSA).

Methods

We followed 69 117 employees of the general working population (Work Environment and Health in Denmark study 2012–2018), without LTSA during the past 52 weeks preceding initial interview, for up to 2 years in the Danish Register for Evaluation of Marginalisation. Self-reported physical work demands were based on a combined ergonomic index including seven different types of exposure during the working day. Using weighted Cox regression analyses controlling for years of age, gender, survey year, education, lifestyle, depressive symptoms and psychosocial work factors, we determined the interaction of age with physical work demands for the risk of LTSA.

Results

During follow-up, 8.4% of the participants developed LTSA. Age and physical work demands interacted (p<0.01). In the fully adjusted model, very high physical work demands were associated with LTSA with HRs of 1.18 (95% CI 0.93 to 1.50), 1.57 (95% CI 1.41 to 1.75) and 2.09 (95% CI 1.81 to 2.41) for 20, 40 and 60 years old (point estimates), respectively. Results remained robust in subgroup analyses including only skilled and unskilled workers and stratified for gender.

Conclusion

The health consequences of high physical work demands increase with age. Workplaces should consider adapting physical work demands to the capacity of workers in different age groups.

Efficacy of an indicated prevention strategy on sickness absence and termination of the employment contract: a 5-year follow-up study

Objective:

It was shown that an indicated prevention strategy (IPS), based on screening and early intervention, can considerably decrease future risk of long-term sickness absence (LTSA>28 days) over one year. Given the nature of the interventions, the potential of an effect extending beyond the original one year of follow-up might be present. This study aims to determine the efficacy of this IPS on LTSA and termination of employment contract over five years by extended follow up of IPS trials.

Methods:

Company records on sickness absence and termination of employment contract over five years were used from two randomized controlled trials (RCT) on the efficacy of the IPS (RCT I employees at high-risk for LTSA: intervention: N=263; RCT II high-risk employees with concurrent mild depressive complaints: intervention: N=139). Survival analysis was used to model time until the first LTSA episode and termination of employment contract.

Results:

RCT I showed a decrease of 43.2 days of sickness absence (P=0.05) and a lower 5-year risk of LTSA in the intervention, as compared to the control group [hazard ratio (HR) 0.61, 95% confidence interval (CI) 0.41–0.90], however no considerable impact on employment contract (HR 0.85, 95% CI 0.54–1.35) (intention-to-treat, ITT). For RCT II, we found no large difference in days of SA and no difference in LTSA risk over five years (HR 1.31, 95% CI 0.70–2.47), whereas the risk of termination of the employment contract was lower (HR 0.62, 95% CI 0.39–0.99) (ITT).

Conclusion:

Effects of the IPS were observed over five years, albeit differential between the two approaches. A combination of elements of both interventions might lead to optimal results but needs further study.

Combined ergonomic exposures and development of musculoskeletal pain in the general working population: A prospective cohort study

Objective:

This study aimed to investigate the importance of combined ergonomic exposures at work for the development of musculoskeletal pain.

Methods:

Through four rounds (2012–2018) of the Work Environment and Health in Denmark Study, 18 905 employees of the general working population replied to a baseline and 2-year follow-up questionnaire. First, a k-means cluster analysis of seven ergonomic factors (back bending, arm above shoulders, lifting etc., from ‘never’ to ‘almost all the time’) identified nine naturally occurring clusters. Second, using a weighted survey regression model controlling for age, gender, survey year, education, lifestyle, influence at work, and pain intensity at baseline, we estimated development of pain intensity (0–10) in the neck-shoulder and low-back in these clusters. The largest cluster served as reference to the other clusters and was characterized by low ergonomic exposures.

Results:

Clusters characterized by multiple combined ergonomic exposures for a relatively high percentage of the working time showed the largest increase in neck-shoulder as well as low-back pain intensity from baseline to follow-up. However, clusters characterized by high exposure to a few specific ergonomic factors also increased pain significantly, eg, standing/walking combined with lifting/carrying or twisted/bent back for the majority of the working time increased low-back pain, whereas repetitive arm movements for the majority of the working time with or without standing/walking increased neck-shoulder pain.

Conclusion:

Combined occupational ergonomic exposures play an important role in the development of musculoskeletal pain. Workplace preventive approaches should consider this in risk assessments and organization of the work.

Leisure-Time Physical Activity Reduces the Risk of Long-Term Sickness Absence Among Older Healthy Female Eldercare Workers

PURPOSE

This study aimed to examine the association between leisure-time physical activity (PA) and risk of long-term sickness absence (LTSA).

DESIGN

Data on LTSA (≥3 consecutive weeks during a 1-year follow-up) were acquired from the Danish Register for Evaluation of Marginalization and linked to a questionnaire via personal identification number.

SETTING

Eldercare workers from 36 Danish municipalities.

SUBJECTS

Data were retrieved from 4605 healthy Danish female eldercare (i.e., workers assisting senior citizens with daily activities and health) aged 19 to 69 years, who answered a questionnaire on health, and work environment in 2005.

MEASURES

Calculated risk of LTSA and its association with self-reported leisure-time PA.

ANALYSIS

A Cox proportional hazards model was used to calculate adjusted hazard ratios (HR) and 95% confidence intervals (95% CI).

RESULTS

Eldercare workers showed significantly reduced risk of LTSA when performing moderate (HR = 0.67, 95%CI 0.47-0.96), and vigorous leisure-time PA (HR = 0.45, 95%CI 0.25-0.81) (reference group: sedentary). In subgroup analyses, females over 45 years showed a risk reduction of LTSA for moderate (HR = 0.54, 95%CI 0.32-0.90), and vigorous leisure-time PA (HR = 0.43, 95%CI 0.18-0.99), whereas younger eldercare workers did not show significant risk reductions for either moderate (HR = 0.86, 95%CI 0.51-1.43) or vigorous leisure-time PA (HR = 0.50, 95%CI 0.21-1.16) in the fully adjusted model.

CONCLUSIONS

The results indicate that moderate and, particularly, vigorous leisure-time PA reduced risk of LTSA in eldercare workers aged over 45 years.

Joint association of physical work demands and leg pain intensity for work limitations due to pain in senior workers: cross-sectional study

Background

Leg pain, especially of the knees and hips, is common among senior workers and may limit the ability to perform physically demanding work. In light of the aging workforce, this study determined the joint association of physical work demands and leg pain intensity for work-limiting pain in senior workers.

Methods

Currently employed senior workers (≥50 years) participated in the SeniorWorkingLife study in 2018 (n = 12,879). Associations between the combination of physical work demands and leg pain intensity (interaction) with work-limiting pain (outcome) were modeled using binary logistic regression analyses while controlling for potential covariates.

Results

We found a significant interaction (P < 0.001) between physical work demands and leg pain intensity for work-limiting pain. The combination of higher physical work demands and higher leg pain intensity had the worst outcome in terms of the odds of experiencing work-limiting pain. For example, 70% of those with the combination of high physical work demands and leg pain intensity ≥7 (scale 0–10) experienced that the pain limited them to at least some degree in their work.

Conclusions

The combination of high physical work demands and high leg pain intensity are associated with limited ability to perform work among senior workers. These findings highlight the importance of prioritizing the physical work environment in physically demanding occupations, particularly among senior workers, for prolonging working life. Thus, adjusting the work demands, e.g. through use of assistive devices, and lowering the pain, e.g. through physical rehabilitation, may be necessary to sustain work ability to a high age in this group of workers.

Trial registration

This was registered as a cohort study in ClinicalTrials.gov (Identifier: NCT03634410) on the 18th of August 2018 (Retrospectively registered).

Work limitations due to neck-shoulder pain and physical work demands in older workers: cross-sectional study

PURPOSE

Many older workers are working despite having neck-shoulder pain (NSP), which may give rise to work limitations due to pain, especially among those with high physical work demands. This study investigated the joint association of neck-shoulder pain intensity and physical work demands with work limitations among older workers.

METHODS

In SeniorWorkingLife, workers ≥ 50 years (n = 11,800) replied to questions about NSP intensity, work limitations due to pain, and physical activity demands at work. The odds ratio for having a higher level of work limitations due to pain in relation to neck-shoulder pain intensity and physical work demands were modeled using logistic regression controlled for various confounders.

RESULTS

The results showed that the neck-shoulder pain intensity was associated with work limitations in a dose-response fashion (p < 0.0001). Importantly, a significant interaction existed between neck-shoulder pain intensity and physical activity at work (p < 0.0001), e.g., 77% of workers with high pain and high work demands experienced work limitations due to the pain.

CONCLUSION

Higher neck-shoulder pain intensity and higher physical work demands-and particularly in combination-were associated with higher odds of work limitation due to pain among older workers. Thus, it seems especially important to accommodate work demands through a better work environment for these groups of workers.

Associations between physical and psychosocial work environment factors and sickness absence incidence depend on the lengths of the sickness absence episodes: a prospective study of 27 678 Danish employees

Objectives

This study examined if the association between work environment factors and sickness absence (SA) depended on the inclusion or exclusion of short-term SA episodes.

Methods

We linked the ‘Work Environment and Health in Denmark’ survey with the ‘Danish Register of Work Absences’ (n=27 678). Using covariate adjusted Cox regression, we examined the associations between work environment factors and SA by changing the cut-off points for the length of the SA episodes, for example, episodes ≥1 day, ≥6 days and ≥21 days. We examined three physical work environment factors: ‘Back bend or twisted’, ‘Lifting or carrying’, ‘Wet hands’ and three psychosocial work environment factors: ‘Poor influence’, ‘Role conflicts’ and ‘Bullying’.

Results

‘Back bend or twisted’ and ‘Lifting or carrying’ had small significant HRs for SA episodes ≥1 day and large and highly significant HRs for SA episodes ≥6 days and ≥21 days. ‘Wet hands’ had small significant HRs for SA episodes ≥1 day for both sexes and large and highly significant HR for ≥6 days for women. HRs of all three psychosocial factors were highly significant for SA episodes ≥1 day and ≥6 days for both sexes, and ‘Poor influence’ and ‘Role conflicts’ were significant for SA episodes ≥21 days for women.

Conclusions

The physical work factors had higher associations with SA when SA episodes of 1–5 days were excluded and focus was on SA episodes ≥6 days. The psychosocial work factors were strongly associated with SA both with and without SA episodes of 1–5 days included in the analyses.

Work factors facilitating working beyond state pension age: Prospective cohort study with register follow-up

Objectives:

The demographic changes in Europe underline the need for an extension of working lives. This study investigates the importance of physical work demands and psychosocial work factors for working beyond the state pension age (65 years).

Methods:

We combined data from three cohorts of the general working population in Denmark (DWECS 2005 and 2010, and DANES 2008), where actively employed workers aged 55–59 years replied to questionnaires about work environment and were followed until the age of 66 years in the Danish AMRun register of paid employment. Using logistic regression analyses, we calculated prevalence ratios (PR) and 95% confidence intervals (CI) for the association between physical and psychosocial work factors and working beyond state pension age, adjusted for age, sex, cohort, cohabiting, sector, income, vocational education, working hours, lifestyle, and previous sickness absence.

Results:

Of the 2884 workers aged 55–59 years, 1023 (35.5%) worked beyond the state pension age. Higher physical work demands was associated with a lower likelihood (PR 0.69, 95% CI 0.58–0.82) and a good psychosocial work environment was associated with higher likelihood (average of 7 items: PR 1.81, 95% CI 1.49–2.20) of working beyond state pension age. Stratified analyses did not change the overall pattern, ie, a good overall psychosocial work environment – as well as several specific psychosocial factors – increased the likelihood of working beyond state pension age, both for those with physically active and seated work.

Conclusion:

While high physical work demands was a barrier, a good psychosocial work environment seems to facilitate working beyond state pension age, also for those with physically active work.

High physical work demands and working life expectancy in Denmark

Objective

In most European countries, political reforms gradually increase the statutory retirement age to counter the economic costs of a growing elderly population. However, working to a high age may be difficult for people with hard physical labour. We aim to study the impact of high physical work demands on working life expectancy (WLE).

Methods

We combined physical work demands assessed by job exposure matrix (JEM) and longitudinal high-quality national registers (outcome) in 1.6 million Danish workers to estimate WLE and years of sickness absence, unemployment and disability pension. The JEM value for physical work demand is a summarised score of eight ergonomic exposures for 317 occupations groups, sex and age. The WLE was estimated using a multistate proportional hazards model in a 4-year follow-up period.

Results

Individuals with high physical work demands had a significantly lower WLE, than those with low physical work demands, with largest differences seen among women. At age 30 years, women with high physical work demands can expect 3.1 years less working, 11 months more of sickness absence and 16 months more of unemployment than low-exposed women. For 30-year-old men, the corresponding results were 2.0 years, 12 months and 8 months, respectively.

Conclusion

Our findings show that high physical work demands are a marked risk factor for a shortened working life and increased years of sickness absence and unemployment. The results are important when selecting high-risk occupations, and expand the knowledge base for informed political decision making concerning statutory retirement age.

Higher leisure-time physical activity is associated with lower sickness absence: cross-sectional analysis among the general workforce

BACKGROUND

Prevention of sickness absence (SA) is a major public health challenge. Sufficient levels of physical activity may be an important protective factor. In contrast to the North European countries, little is known about physical activity behavior and its influence over SA in South European countries.

METHODS

In the European Health Interview Survey (EHIS) 2014, a total of 9512 Spanish workers aged 17 to 70 (46.5% women) replied to questions about SA (last 12 months) and the frequency of leisure-time physical activity (LTPA). Multiple linear regression adjusted for age, sex, education, occupational class, smoking habits, body mass index, and chronic disease (diabetes, hypertension, neck pain, low back pain, chronic depression and anxiety) was used to assess associations.

RESULTS

The average SA among the participants was 6.9 days (SD=33.3) per year, whereas the prevalence of any SA episode was 22.0%. The prevalence of workers performing high or very high LTPA was 31.0%. In final sex and age-stratified fully adjusted models, the association between LTPA and SA remained significant for women aged 44 to 51 (β=-0.07, 95% CI: -0.42 to -0.03) for SA.

CONCLUSIONS

The results suggest that higher LTPA is associated with lower SA in a particular category of workers, that might benefit from physical activity strategies.

Physical and Psychosocial Work Environmental Risk Factors for Back Injury among Healthcare Workers: Prospective Cohort Study

The incidence of occupational back injury in the healthcare sector remains high despite decades of efforts to reduce such injuries. This prospective cohort study investigated the risk factors for back injury during patient transfer. Healthcare workers (n = 2080) from 314 departments at 17 hospitals in Denmark replied to repeated questionnaires sent every 14 days for one year. Using repeated-measures binomial logistic regression, controlling for education, work, lifestyle, and health, the odds for back injury (i.e., sudden onset episodes) were modeled. On the basis of 482 back injury events, a higher number of patient transfers was an important risk factor, with odds ratio (OR) 3.58 (95% confidence interval (CI) 2.51–5.10) for 1–4 transfers per day, OR 7.60 (5.14–11.22) for 5–8 transfers per day, and OR 8.03 (5.26–12.27) for 9 or more transfers per day (reference: less than 1 per day). The lack of necessary assistive devices was a common phenomenon during back injury events, with the top four lacking devices being sliding sheets (30%), intelligent beds (19%), walking aids (18%), and ceiling lifts (13%). For the psychosocial factors, poor collaboration between and support from colleagues increased the risk for back injury, with OR 3.16 (1.85–5.39). In conclusion, reducing the physical burden in terms of number of daily patient transfers, providing the necessary assistive devices, and cultivating good collaboration between colleagues are important factors in preventing occupational back injuries among healthcare workers.

Work-Related Exposures and Sickness Absence Trajectories: A Nationally Representative Follow-up Study among Finnish Working-Aged People

The contribution of physically demanding work to the developmental trajectories of sickness absence (SA) has seldom been examined. We analyzed the associations of 12 physical work exposures, individually and in combination, with SA trajectories among the occupationally active in the Finnish nationally representative Health 2000 survey. We included 3814 participants aged 30–59 years at baseline, when exposure history to work-related factors was reported. The survey and interview responses were linked with the annual number of medically confirmed SA spells through 2002–2008 from national registries. Trajectory analyses identified three SA subgroups: 1 = low (54.6%), 2 = slowly increasing (33.7%), and 3 = high (11.7%). After adjustments, sitting or use of keyboard >1 year was inversely associated with the high SA trajectory (odds ratio, OR, 0.57; 95% 95% confidence interval, CI, 0.43–0.77). The odds of belonging to the trajectory of high SA increased with an increasing number of risk factors, and was highest for those with ≥4 physical workload factors (OR 2.71; 95% CI 1.99–3.69). In conclusion, these findings highlight the need to find ways to better maintain the work ability of those in physically loading work, particularly when there occurs exposure to several workload factors.

Sick leave due to musculoskeletal pain: determinants of distinct trajectories over 1 year

Purpose

This study aimed to identify sub-groups of workers with different trajectories of sick leave due to musculoskeletal pain over 1 year, and to investigate the extent to which the identified trajectories are associated with personal, occupational, lifestyle, and pain-related factors at baseline.

Methods

Data on 981 blue- and white-collar workers were analyzed in the DPHACTO cohort (2012–2014). The number of days on sick leave due to pain was reported using text messages at 4-week intervals across 1 year. Latent class growth analysis was used to distinguish sub-groups with different trajectories of sick leave. A web-based questionnaire at baseline was used to assess personal, occupational (physical and psychosocial), lifestyle, and pain-related factors. Multinomial regression models were constructed to determine associations between baseline factors and trajectories of sick leave (referencing no sick leave), with adjustment for potential confounders.

Results

Four distinct sub-groups were identified, with trajectories of sick leave due to pain ranging from no sick leave (prevalence 76%; average 0.5 days/year) to some days and increasing sick leave due to pain over 1 year (2%; 89 days/year). The increasing trajectory of sick leave was associated with higher perceived physical exertion, more time in manual work, less social community and influence at work, less leisure-time physical activity, smoking, and more severe symptoms (e.g., multisite pain, low back pain intensity, and pain interference).

Conclusions

We identified four distinct trajectories of sick leave due to musculoskeletal pain. The sub-group with increasing sick leave due to pain was associated with several modifiable physical and psychosocial factors at work and outside work, which may have implications for prevention.

Electronic supplementary material

The online version of this article (10.1007/s00420-019-01447-y) contains supplementary material, which is available to authorized users.

Influence of physical and psychosocial working conditions for the risk of disability pension among healthy female eldercare workers: Prospective cohort

Aim: To investigate the influence of physical and psychosocial working conditions on the risk of disability pension among eldercare workers. Methods: After responding to a questionnaire in 2005, 4699 healthy female eldercare workers – free from chronic musculoskeletal pain, depressive symptoms and long-term sickness absence – were followed for 11 years in the Danish Register for Evaluation of Marginalization. Time-to-event analyses estimated the hazard ratio (HR) for disability pension from physical exertion during work, emotional demands, influence at work, role conflicts, and quality of leadership. Analyses were mutually adjusted for these work environmental factors as well as for age, education, smoking, leisure physical activity and body mass index. Results: During follow-up, 7.6% received disability pension. Physical exertion and emotional demands were associated with risk of disability pension, and both interacted with age. In age-stratified analyses, older eldercare workers (mean age 53 years at baseline) with moderate and high physical exertion (reference: low) were at increased risk with HRs of 1.51, 95% CI [1.06–2.15] and 2.54, 95% CI [1.34–4.83], respectively. Younger eldercare workers (mean age 36 years at baseline) with moderate emotional demands (reference: low) were at decreased risk with an HR of 0.57, 95% CI [0.37–0.85]. Conclusions: While a higher level of physical exertion is a risk factor for disability pension among older female eldercare workers, a moderate level of emotional demands is associated with lower risk among the younger workers. The age of the worker may be an important factor when providing recommendations for promoting a long and healthy working life.

Perceived stress and sickness absence: a prospective study of 17,795 employees in Denmark

Objectives

The aims were to examine (1) the prospective association between perceived stress and sickness absence, and if this association (2) differed by sex, and (3) was stronger when only long-term sickness absence (≥ 31 days) instead of all-length sickness absence (≥ 1 day) was included. Moreover, different cut-points for the length of the sickness absence periods were applied.

Methods

We followed respondents (10,634 women and 7161 men) from the ‘Work Environment and Health in Denmark’ 2014-survey for up to 18 months in the ‘Register of Work Absences’ from Statistics Denmark. Perceived stress was measured by a single question: “In the last 2 weeks, how often have you felt stressed?” We used Cox-regression with repeated events, adjusted for age, sector, education, and previous sickness absence.

Results

The hazard ratio (HR) for all-length sickness absence (≥ 1 day) for “Often/Always” stress compared to “Seldom/Never” stress was statistically significant among both men (HR = 1.25 [1.13–1.38]) and women (HR = 1.43 [1.34–1.51]). The HR was statistically significant for women (HR = 2.26 [1.89–2.70]), but not for men (HR = 1.22 [0.86–1.73]), when the analyses were restricted to long-term sickness absence (≥ 31 days). The sex-difference was statistically significant. Additional analyses with cut-points at ≥ 2, ≥ 4, ≥ 6, ≥ 8, ≥ 11, ≥ 15, ≥ 20, and ≥ 25 sickness absence days showed that among women, the HR increased gradually with increasing lengths of the sickness absence periods.

Conclusions

The prospective association of perceived stress with risk of sickness absence was stronger among women than men. Among women, perceived stress was more strongly associated with long-term sickness absence than with all-length sickness absence.

Study protocol for SeniorWorkingLife - push and stay mechanisms for labour market participation among older workers

Background

Due to demographic changes across Europe there are strong political interests in maintaining the labour force by prolonging working life, i.e. increasing retirement age. This may pose both challenges and opportunities for societies, workplaces, and individuals. The SeniorWorkingLife (Danish: SeniorArbejdsLiv) project investigates push and stay mechanisms for labour market participation – now and in the future - among older workers (≥50 years).

Methods

In July 2018, 30,000 Danes age 50 or older (18,000 employed, 7000 unemployed, 3000 voluntary early retirements, 2000 disability pensions) were invited to participate, of which 15,721 (52.4%) replied to the entire questionnaire and 17,885 (59.6%) replied at least in part. Baseline data collection was terminated in October 2018. The questionnaire covers 14 domains in relation to push and stay mechanisms for labour market participation: 1) basic information (demographics, employment status etc.), 2) multiple-choice question covering a wide range of push and stay mechanisms, 3) role of the workplace, 4) age-discrimination, 5) personal economy, 6) possibility for voluntary early retirement among employed and unemployed, 7) gradual retirement, 8) competencies and continued education, 9) return-to-work, 10) new technologies at the workplace, 11) job satisfaction and well-being, 12) working environment, 13) lifestyle, 14) health and functional capacity. The project aspires to repeat the survey as a prospective cohort every 2–3 years and to perform longitudinal follow-up in Danish high-quality registers about work and health.

Discussion

The SeniorWorkingLife project will provide important knowledge about push and stay mechanisms for labour market participation among older workers. Push refers to mechanisms that increase the risk of premature exit from the labour marker, e.g. due to poor health, poor working environment, age discrimination, and stay to mechanisms prolonging working life e.g. due to attractive working conditions and a good working environment. The project will also to some degree investigate stuck, pull and jump mechanisms. Collaboration and use of the data for scientific purposes by other researchers are encouraged. Interested researchers should contact the corresponding author.

Trial Registration

Registered as cohort study in ClinicalTrials.gov Identifier NCT03634410 (August 16, 2018).

Effects of a Participatory Ergonomics Intervention With Wearable Technical Measurements of Physical Workload in the Construction Industry: Cluster Randomized Controlled Trial

Background

Construction work frequently involves heavy physical work, and a reduction of the physical workload should have high priority. Technological development has made it possible to obtain field measurements with surface electromyography (sEMG), kinematics measured with inertial measurement units (IMUs), and video recordings. However, no studies have used these methods simultaneously to detect situations with excessive physical workload (events) during a working day. Thus, knowledge about these specific events may combat work-related risk factors. Participatory ergonomics (PE) has shown promising results, but whether it can be used as a tool to reduce the physical workload during construction work remains unknown.

Objective

This cluster randomized controlled trial investigated whether a PE intervention with technical measurements consisting of IMUs, sEMG, heart rate monitoring, and video recordings of physical workload could reduce the number of events with excessive physical workload during a working day. Furthermore, other outcomes were obtained from questionnaires.

Methods

A total of 80 male full-time construction workers (aged 19 to 67 years) were randomized at the cluster level (gang) to a PE intervention consisting of 3 workshops (7 gangs and 32 workers) or to a control group (8 gangs and 48 workers). The physical workload was recorded by technical measurements, that is, IMUs, sEMG, heart rate monitoring, and video recordings during a full working day at baseline and 3 and 6 months’ follow-up. On the basis of the technical measurements, a custom-made computer program detected the situations (events) where the construction workers were exposed to excessive physical workload and used in the intervention. Differences in the number of events from baseline to follow-up between intervention and control were evaluated using linear mixed models (intention-to-treat), with individual nested in cluster as a random factor. Furthermore, questionnaires were filled out on test days.

Results

The results of the primary outcome showed no change in the number of events with excessive physical workload. However, compared with the control group, the other outcomes showed decreased general fatigue after a typical working day (P=.001) and increased influence on own work (P=.04).

Conclusions

This PE intervention with technical measurements did not reduce the number of events with excessive physical workload during construction work. However, the intervention led to decreased general fatigue and increased influence on own work.

Trial Registration

ClinicalTrials.gov NCT02498197; https://clinicaltrials.gov/ct2/show/NCT02498197 (Archived by WebCite at http://www.webcitation.org/74SZ3DIWS)