The impact of workplace risk factors on long-term musculoskeletal sickness absence: a registry-based 5-year follow-up from the Oslo health study

Are Work Demand, Support and Control Associated with Work Ability and Disability during Back Pain Treatment? A Prospective Explorative Study

Background: Low back pain is a multifactorial disease with consequences for work ability and social participation. Improved integration of the work domain in health care management is needed. The aim of this study was to explore the relation between working conditions with outcome of low back pain treatment. Methods: Observational study of 41 patients attending physiotherapy for low back pain. Work demands, support and control were registered at baseline and work ability and disability also at baseline, with follow up after three and nine months. We used mixed-effects models to estimate the longitudinal associations between working conditions and outcome. Results: Higher work demands were related to reduced work ability (−1.1 points, 95% CI: −2.1 to −0.1) and slightly increased disability (5.6 points, 95% CI: 0.5 to 10.7). Lack of social support from colleagues was associated with reduced work ability (−2.7 points, 95% CI: −0.2 to 1.5) and disability (14.0 points, 95% CI: 4.9 to 23.1). Conclusions: This explorative study found associations between work demands and support, and work ability and disability outcome. Screening for psychosocial working conditions may influence the work ability and disability treatment outcome. The results need replication in larger samples and may indicate that patients seeking primary care management for low back pain should be screened for work demands, support and control.

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.

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.

Occupational and non-occupational risk factors of sickness absence due to a shoulder lesion

Objectives

To determine the associations of lifestyle factors and cumulative physical workload exposures with sickness absence (SA) due to a shoulder lesion and to calculate their population attributable fractions (PAF).

Methods

Our nationally representative cohort consisted of 4344 individuals aged 30–62 years who participated in the Finnish Health 2000 Survey. Education, smoking, chronic diseases and work exposures were assessed during interviews and leisure time physical activity with a questionnaire. Weight and height were measured. We followed the individuals for 15 years for the first SA due to a shoulder lesion. We used competing risk regression models. We calculated PAFs to assess the proportion of SA that was attributed to modifiable risk factors.

Results

In the entire study population, risk factors of SA were age, daily smoking, being exposed for more than 10 years to physically heavy work and being exposed for more than 10 years to at least two specific physical workload factors. The overall PAF for the modifiable risk factors was 49%. In men, number of specific cumulative exposures, obesity and daily smoking predicted SA with PAF values of 34%, 30% and 14%, respectively. Among women, being exposed for more than 10 years to physically heavy work, number of specific cumulative exposures and daily smoking accounted for 23%, 22% and 15% of SA, respectively.

Conclusions

Reducing significantly prolonged exposure to physical workload factors, avoiding regular smoking in both genders and obesity in men has a high potential to prevent SA due to a shoulder lesion.

Physical and psychosocial work environmental risk factors of low-back pain: protocol for a 1 year prospective cohort study

Background

Musculoskeletal disorders, and in particular low-back pain (LBP), are common among blue collar workers. In the work environment, both physical- and psychosocial risk factors exist. Working in warehouses in Denmark involve large quantities of occupational lifting, high work pace and a low degree of influence at work. This study investigates both acute and long-term associations between physical- and psychosocial work environmental factors and risk of LBP in warehouse workers. The specific study aims are to investigate 1) exposure-response associations between quantity of occupational lifting and short-term (day-to-day) changes in LBP, 2) the influence of accumulated workdays and rest days during a working week on LBP, 3) long-term association between occupational lifting exposure and LBP when assessed over 1 year, and 4) the role of psychological and social factors on the above associations.

Methods

The present study is designed as a 1-year prospective cohort study that will examine full-time warehouse workers from up to five retail chains in Denmark. Study aims 1 and 2 will be addressed using objective data based on company records with information on weight of all the goods handled by each warehouse worker during every single workday for 3 weeks. During this period, each worker will reply to text messages received before and after every workday (also on days off work) in which study participants will score their pain in the low back, bodily fatigue and perceived mental stress (scale 0–10). Long-term pain development is assessed using questionnaire surveys before and after 1 year. Further, pressure pain threshold (PPT) will be measured for selected trunk extensor muscles in approximately 50 workers using algometry along with measurements of maximal trunk extensor strength. Associations are modelled using linear mixed models with repeated measures between variables and LBP controlled for relevant confounders.

Discussion

This study provides knowledge about the acute and long-term associations between physical- and psychosocial work environmental factors and LBP. The obtained data will have the potential to provide recommendations on improved design of the working week to minimize the risk of LBP among warehouse workers, and may potentially enable to identify a reasonable maximum lifting threshold per day (ton lifted/day).

Working conditions and compensated sickness absence among nurses and care assistants in Sweden during two decades: a cross-sectional biennial survey study

OBJECTIVES

The aims of the study were to trace the patterns of work environment factors and compensated sickness absence (SA) among nurses and care assistants compared with other occupations and to compare SA among exposed and non-exposed nurses and care assistants.

DESIGN

A cross-sectional survey on work environment factors based on the biennial Swedish Work Environment Surveys 1991-2013, linked to longitudinal register data on SA 1993-2014.

PARTICIPANTS

The study included 98 249 individuals, stratified into nurses and care assistants (n=16 179) and a reference population including all other occupations (n=82 070).

OUTCOME MEASURE

Annual days of compensated SA (>14 days) 3 years after exposure years.

RESULTS

Nurses and care assistants had higher SA in 1993-2014 compared with all other occupations, and differences in background factors only partly explained this relationship. For both groups, exposure to physical work factors remained steady, but the number of exposed were 10%-30% higher among nurses and care assistants. Those exposed to heavy physical work and strenuous working postures had in most years significantly higher SA when compared with non-exposed (rate ratio range: 1.4-1.9). Exposure to high job demands increased 10%-25% in 1991-1999 among nurses and care assistants but became more stable in 2001-2013 and high proportions of high job demands coincided with the increase in SA in 1995-1999. Nurses and care assistants exposed to high job demands had for most years significantly higher SA than non-exposed (rate ratio range: 1.5-2.1). Low job control and low support from supervisors elevated SA significantly only for a few years.

CONCLUSIONS

Exposure to negative work factors among nurses and care assistants was weakly associated with variations in SA, but may be related to their higher level of SA when compared with other occupations. Improved physical and psychosocial working conditions may reduce the elevated SA level in these occupations.

Exposure to heavy physical work from early to later adulthood and primary healthcare visits due to musculoskeletal diseases in midlife: a register linked study

OBJECTIVES

To examine whether exposure to heavy physical work from early to later adulthood is associated with primary healthcare visits due to cause-specific musculoskeletal diseases in midlife.

DESIGN

Prospective cohort study.

SETTING

Nationally representative Young Finns Study cohort, Finland.

PARTICIPANTS

1056 participants of the Young Finns Study cohort.

EXPOSURE MEASURE

Physical work exposure was surveyed in early (18-24 years old, 1986 or 1989) and later adulthood (2007 and 2011), and it was categorised as: 'no exposure', 'early exposure only', 'later exposure only' and 'early and later exposure'.

PRIMARY AND SECONDARY OUTCOME MEASURES

Visits due to any musculoskeletal disease and separately due to spine disorders, and upper extremity disorders were followed up from national primary healthcare register from the date of the third survey in 2011 until 2014.

RESULTS

Prevalence of any musculoskeletal disease during the follow-up was 20%, that for spine disorders 10% and that for upper extremity disorders 5%. Those with physically heavy work in early adulthood only had an increased risk of any musculoskeletal disease (risk ratio (RR) 1.55, 95% CI 1.05 to 2.28) after adjustment for age, sex, smoking, body mass index, physical activity and parental occupational class. Later exposure only was associated with visits due to any musculoskeletal disease (RR 1.46, 95% CI 1.01 to 2.12) and spine disorders (RR 2.40, 95% CI 1.41 to 4.06). Early and later exposure was associated with all three outcomes: RR 1.99 (95% CI 1.44 to 2.77) for any musculoskeletal disease, RR 2.43 (95% CI 1.42 to 4.14) for spine disorders and RR 3.97 (95% CI 1.86 to 8.46) for upper extremity disorders.

CONCLUSIONS

To reduce burden of musculoskeletal diseases, preventive actions to reduce exposure to or mitigate the consequences of physically heavy work throughout the work career are needed.

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

Background

The working environment plays an important role in public health. This study investigates the risk for long-term sickness absence (LTSA) from the combination of factors related to physical work demands.

Methods

Employees (n = 22 740) of the general population (the Danish Work Environment & Health study 2012) were followed for two years in the Danish Register for Evaluation of Marginalisation. Using Cox regression analyses we determined the risk of LTSA from four factors; (i) physical work demands, (ii) physical exertion during work, (iii) fatigue after work and (iv) work-limiting pain.

Results

During follow-up 10.2% experienced LTSA. Each of the four factors increased the risk of LTSA with hazard ratios (HR) ranging from 1.30 to 1.57. Scoring high on one (30.3% of the respondents), two (24.4%), three (19.9%) and all four factors (9.2%) gradually increased the risk of LTSA (HR’s of 1.39 [95% CI 1.16–1.66], 1.66 [95% CI 1.39–1.99], 1.90 [95% CI 1.57–2.29] and 3.02 [95% CI 2.47–3.68], respectively). Risk estimates remained robust in stratified analyses of age, sex and socioeconomic position. Population attributable fractions were high across all subgroups; 39% (general population), 36% (younger workers), 45% (older workers), 36% (men), 41% (women), 30% (higher socioeconomic position) and 45% (lower socioeconomic position).

Conclusion

The risk of LTSA gradually increased with number of factors related to high physical work demands, underlining the importance of targeting combined factors in risk assessment and preventive interventions.

Validity and responsiveness of the work functioning impairment scale (WFun) in workers with pain due to musculoskeletal disorders

Objective:

To determine the convergent validity and responsiveness of the work functioning impairment scale (WFun) in workers with musculoskeletal disorder-related pain.

Methods:

Participants were extracted from an internet user study and prospectively examined using the pain intensity numerical rating scale (pain-NRS), the work ability numerical rating scale (productivity-NRS), and the WFun at baseline, 2 weeks, 6 weeks, and 3 months. The convergent validity and responsiveness of the WFun were examined by multilevel regression analysis.

Results:

A total of 786 workers participated and 593 completed all surveys. The WFun score gradually increased and decreased as the pain-NRS and the productivity-NRS increased, respectively. Changes in the WFun score steadily increased and decreased as changes in the pain-NRS and the productivity-NRS increased, respectively. Multilevel analyses showed that all linear associations were significant.

Conclusions:

The convergent validity and responsiveness of the WFun were consistent with the expected direction and magnitude.

Occupational and leisure-time physical activity and risk of disability pension: prospective data from the HUNT Study, Norway

OBJECTIVES

To prospectively investigate the association between occupational physical activity (OPA) and disability pension due to musculoskeletal cause, mental cause or any cause. We also examined the combined association of OPA and leisure-time physical activity (LTPA) with disability pension.

METHODS

A population-based cohort study in Norway on 32 362 persons aged 20-65 years with questionnaire data on OPA and LTPA that were followed up for incident disability pension through the National Insurance Database. We used Cox regression to estimate adjusted HRs with 95% CIs.

RESULTS

During a follow-up of 9.3 years, 3837 (12%) received disability pension. Compared with people with mostly sedentary work, those who performed much walking, much walking and lifting, and heavy physical work had HRs of 1.26 (95% CI 1.16 to 1.38), 1.44 (95% CI 1.32 to 1.58) and 1.48 (95% CI 1.33 to 1.70), respectively. These associations were stronger for disability pension due to musculoskeletal disorders, whereas there was no clear association between OPA and risk of disability pension due to mental disorders. People with high OPA and low LTPA had a HR of 1.77 (95% CI 1.58 to 1.98) for overall disability pension and HR of 2.56 (95% CI 2.10 to 3.11) for disability pension due to musculoskeletal disorders, versus low OPA and high LTPA.

CONCLUSIONS

We observed a positive association between OPA and risk of disability pension due to all causes and musculoskeletal disorders, but not for mental disorders. Physical activity during leisure time reduced some, but not all of the unfavourable effect of physically demanding work on risk of disability pension.

Demand, Control and Support at Work Among Sick-Listed Patients with Neck or Back Pain: A Prospective Study

Purpose The main aim of this study was to assess changes in perceived demand, control and support at work of neck and back pain patients over 1 year. We also hypothesised that perceived changes in demand, control and support at work were associated with clinical improvement, reduced fear-avoidance beliefs and successful return to work. Methods Four hundred and five sick-listed patients referred to secondary care with neck or back pain were originally included in an interventional study. Of these, two hundred and twenty-six patients reported perceived psychosocial work factors at both baseline and 1-year follow-up, and they were later included in this prospective study. Changes in demand, control and support dimensions were measured by a total of nine variables. Results At the group level, no significant differences were found among the measured subscales. At the individual level, the regression analyses showed that decreases in fear-avoidance beliefs about work were consistently related to decreases in demand and increases in control, whereas decreases in disability, anxiety and depression were related to increases in support subscales. Conclusions The perception of demand, control and support appear to be stable over 1 year in patients with neck and back pain, despite marked improvement in pain and disability. Disability, anxiety, depression and fear-avoidance beliefs about work were significantly associated with the perception of the work environment, whereas neck and back pain were not.

Physical workload and risk of long-term sickness absence in the general working population and among blue-collar workers: prospective cohort study with register follow-up

OBJECTIVE

To determine the prospective association between physical workload--in terms of specific physical exposures and the number of exposures--and long-term sickness absence (LTSA).

METHODS

Using cox-regression analyses, we estimated the risk of register-based incident LTSA (at least 3 consecutive weeks) from self-reported exposure to different physical workloads among 11,908 wage earners from the general working population (Danish Work Environment Cohort Study year 2000 and 2005).

RESULTS

The incidence of LTSA was 8.9% during two-year follow-up. Spending 25% or more of the total work time with a bent or twisted back (HR 1.59 (95% CI 1.39 to 1.83)), arms above shoulder height (HR 1.35 (95% CI 1.14 to 1.59)), squatting or kneeling (HR 1.30 (95% CI 1.09 to 1.54)), pushing/pulling or lifting/carrying (HR 1.40 (95% CI 1.22 to 1.62)) and standing in the same place for 50% or more of total work time (HR 1.19 (95% CI 1.00 to 1.42), were risk factors for LTSA when adjusted for baseline age, gender, psychosocial work environment, lifestyle, musculoskeletal and mental disorders, and socioeconomic status. HR increased from 1.25 (95% CI 1.04 to 1.51) for one to 1.94 (95% CI 1.56 to 2.41) for four combined physical workloads. Results largely remained stable in subgroup analyses including only blue-collar workers (n=5055). Population attributable risks for LTSA from one or more physical workloads were 26% and 40% in the general working population and among blue-collar workers, respectively.

CONCLUSIONS

Several of the investigated types of physical workload were risk factors for LTSA when exceeding 25% of the work time. A higher number of combined physical workloads was associated with progressively increased risk. Our study underscores the importance of physical workload as risk factors for LTSA in the general working population as well as among blue-collar workers.

What Challenges Manual Workers' Ability to Cope with Back Pain at Work, and What Influences Their Decision to Call in Sick?

INTRODUCTION

Although back pain (BP) is a very common cause for sickness absence, most people stay at work during BP episodes. Existing knowledge on the factors influencing the decision to stay at work despite pain is limited. The aim of this study was to explore challenges for coping with BP at work and decisive factors for work attendance among workers with high physical work demands.

METHODS

Three focus groups (n = 20) were conducted using an explorative inductive method. Participants were public-employed manual workers with high physical work demands. All had personal BP experience. Thematic analysis was used for interpretation. Results were matched with the Flags system framework to guide future recommendations.

RESULTS

Workers with BP were challenged by poor physical work conditions and a lack of supervisor support/trust (i.e. lack of adjustment latitude). Organization of workers into teams created close co-worker relationships, which positively affected BP coping. Workers responded to BP by applying helpful individual adjustments to reduce or prevent pain. Traditional ergonomics was considered inconvenient, but nonetheless ideal. When pain was not decisive, the decision to call in sick was mainly governed by workplace factors (i.e. sick absence policies, job strain, and close co-workers relationships) and to a less degree by personal factors.

CONCLUSION

Factors influencing BP coping at work and the decision to report sick was mainly governed by factors concerning general working conditions. Creating a flexible and inclusive working environment guided by the senior management and overall work environment regulations seems favourable.

Prolonged performance of a high repetition low force task induces bone adaptation in young adult rats, but loss in mature rats

We have shown that prolonged repetitive reaching and grasping tasks lead to exposure-dependent changes in bone microarchitecture and inflammatory cytokines in young adult rats. Since aging mammals show increased tissue inflammatory cytokines, we sought here to determine if aging, combined with prolonged performance of a repetitive upper extremity task, enhances bone loss. We examined the radius, forearm flexor muscles, and serum from 16 mature (14-18 months of age) and 14 young adult (2.5-6.5 months of age) female rats after performance of a high repetition low force (HRLF) reaching and grasping task for 12 weeks. Young adult HRLF rats showed enhanced radial bone growth (e.g., increased trabecular bone volume, osteoblast numbers, bone formation rate, and mid-diaphyseal periosteal perimeter), compared to age-matched controls. Mature HRLF rats showed several indices of radial bone loss (e.g., decreased trabecular bone volume, and increased cortical bone thinning, porosity, resorptive spaces and woven bone formation), increased osteoclast numbers and inflammatory cytokines, compared to age-matched controls and young adult HRLF rats. Mature rats weighed more yet had lower maximum reflexive grip strength, than young adult rats, although each age group was able to pull at the required reach rate (4 reaches/min) and required submaximal pulling force (30 force-grams) for a food reward. Serum estrogen levels and flexor digitorum muscle size were similar in each age group. Thus, mature rats had increased bone degradative changes than in young adult rats performing the same repetitive task for 12 weeks, with increased inflammatory cytokine responses and osteoclast activity as possible causes.

Work-related psychosocial risk factors for long-term sick leave: a prospective study of the general working population in Norway

OBJECTIVE

To examine the effect of work-related psychosocial exposures on long-term sick leave (LTSL) in the general working population.

METHODS

A prospective study of the general working population in Norway. Eligible respondents were interviewed in 2009 and registered with at least 100 working days in 2009 and 2010 (n = 6758). The outcome was medically confirmed LTSL of 40 days or more during 2010.

RESULTS

In the fully adjusted model, high exposure to role conflict (odds ratio [OR], 1.58; 95% confidence interval [CI], 1.20 to 2.09), emotional demands (OR, 1.32; 95% CI, 1.03 to 1.69), and low supportive leadership (OR = 1.50; 95% CI, 1.15 to 1.96) predicted LTSL. A test for trend was statistically significant for all factors (P ≤ 0.05). We estimated that 15% of LTSL cases were attributable to these factors.

CONCLUSIONS

This study underlines the importance of taking into account psychosocial exposures as risk factors for LTSL.

Role of inflammation in the aging bones

Chronic inflammation in aging is characterized by increased inflammatory cytokines, bone loss, decreased adaptation, and defective tissue repair in response to injury. Aging leads to inherent changes in mesenchymal stem cell (MSC) differentiation, resulting in impaired osteoblastogenesis. Also, the pro-inflammatory cytokines increase with aging, leading to enhanced myelopoiesis and osteoclastogenesis. Bone marrow macrophages (BMMs) play pivotal roles in osteoblast differentiation, the maintenance of hematopoietic stem cells (HSCs), and subsequent bone repair. However, during aging, little is known about the role of macrophages in the differentiation and function of MSC and HSC. Aged mammals have higher circulating pro-inflammatory cytokines than young adults, supporting the hypothesis of increased inflammation with aging. This review will aid in the understanding of the potential role(s) of pro-inflammatory (M1) and anti-inflammatory (M2) macrophages in differentiation and function of osteoblasts and osteoclasts in relation to aging.

Influence of lifestyle factors on long-term sickness absence among female healthcare workers: a prospective cohort study

Background

While previous research has indicated that unhealthy lifestyle is associated with sickness absence, this association may be confounded by occupational class. To avoid this potential confounding, we examined the association between lifestyle factors (smoking, leisure-time physical activity and body mass index) and the occurrence of long-term sickness absence (LTSA; more than three consecutive weeks of registered sickness absence) within a cohort of female health care workers.

Methods

A total of 7401 employees filled out a questionnaire about their health behaviour and work environment. Subsequently, they were followed for 12 months in a national register on social transfer payments (DREAM register). Cox’s regression analyses, applied to grouped survival data, were used to estimate the prospective association between these lifestyle factors and LTSA.

Results

We found significant associations between all three lifestyle factors and risk of LTSA. The strongest lifestyle factor was current smoking, which increased the risk of LTSA by 35% (95% CI: 1.17-1.54) compared to non- smokers. For body mass index, the risk of LTSA increased with the distance away from 18.5 kg/m² in either direction (below 18.5 kg/m²: HR: 1.32 per kg/m²; 95% CI. 1.06-1.66; above 18.5 kg/m²: HR: 1.04 per kg/m²; 95% CI: 1.03-1.05). In other words, the more underweight or overweight the women were, the higher the risk of LTSA. A dose–response relationship was found between LTSA and leisure-time physical activity (trend test p-value = 0.01), so that increasing physical activity results in decreasing risk of LTSA.

Conclusion

In female healthcare workers, an unhealthy lifestyle (too high/ too low body mass index, smoking, and low physical activity) is associated with higher risk of LTSA.

Psychosocial and organizational risk factors for doctor-certified sick leave: a prospective study of female health and social workers in Norway

Background

Doctor-certified sick leave differs substantially across sectors, and among health and social workers, in particular, there is an increased risk. Previous studies have shown that work environmental factors contribute to sick leave. Hence, the identification of specific organizational and psychosocial risk factors for long- term sick leave, taking into account potential confounding related to mechanical risk factors such as lifting and awkward body postures, will be of importance in the work of prevention.

Methods

A randomly drawn population sample of Norwegian residents was interviewed about working conditions in 2009 (n = 12,255; response rate 60.9%). Female health and social care workers (n = 925) were followed in a national registry for subsequent sickness absence during 2010. The outcome of interest was doctor-certified sick leave of 21 days or more (long-term sick leave). Eleven work-related psychosocial and organizational factors were evaluated.

Results

In total, 186 persons (20.1%) were classified with subsequent long-term sick leave. After thoroughly adjusting for competing explanatory variables, the most consistent predictors for long-term sick leave were violence and threats of violence (OR = 1.67; 95% CI 1.14–2.45). The estimated population attributable risk for violence and threats of violence was 13%.

Conclusions

The present study among female health and social care workers revealed a substantial relationship between self-reported violence and threats of violence and subsequent long- term sick leave.

"Inclusive working life in Norway": a registry-based five-year follow-up study

BACKGROUND

In 2001, the Norwegian authorities and major labour market partners signed an agreement regarding 'inclusive working life' (IW), whereby companies that participate are committed to reducing sickness absence. Our main aim was to determine the effect of the IW program and work characteristics by gender on long-term (>8 weeks) sickness absence (LSA).

METHODS

Self-reported data on work characteristics from the Oslo Health Study were linked to registry-based data on IW status, education and LSA. From 2001-2005, 10,995 participants (5,706 women and 5,289 men) aged 30, 40, 45 and 60 years were followed. A Cox regression was used to compute hazard ratios (HR) for LSA risk. The cohort was divided into an IW group (2,733 women and 2,058 men) and non-IW group (2,973/3,231).

RESULTS

43.2% and 41.6% of women and 22.3%/24.3% of men (IW / non-IW, respectively) experienced at least one LSA. In a multivariate model, statistically significant risk factors for LSA were low education (stronger in men), shift work/night work or rotating hours (strongest in men in the non-IW group), and heavy physical work or work involving walking and lifting (men only and stronger in the non-IW group). Among men who engaged in shift work, the LSA risk was significantly lower in the IW group.

CONCLUSIONS

Our results could suggest that IW companies that employ many men in shift work have implemented relevant efforts for reducing sickness absence. However, this study could not demonstrate a significant effect of the IW program on the overall LSA risk.

Shiftwork and sickness absence among police officers: the BCOPS study

Shiftwork, regarded as a significant occupational stressor, has become increasingly prevalent across a wide range of occupations. The adverse health outcomes associated with shiftwork are well documented. Shiftwork is an integral part of law enforcement, a high-stress occupation with elevated risks of chronic disease and mortality. Sickness absence is an important source of productivity loss and may also serve as an indirect measure of workers' morbidity. Prior studies of shiftwork and sickness absenteeism have yielded varying results and the association has not been examined specifically among police officers. The objective of this study was to compare the incidence rate of sick leave (any, ≥3 consecutive days) among day-, afternoon-, and night-shift workers in a cohort of police officers and also examine the role of lifestyle factors as potential moderators of the association. Participants (N=464) from the Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) study examined between 2004 and 2009 were used. Daily work history records that included the shift schedule, number of hours worked, and occurrence of sick leave were available for up to 15 yrs starting in 1994 to the date of the BCOPS study examination for each officer. Poisson regression analysis for ungrouped data was used to estimate incidence rates (IRs) of sick leave by shift, and comparison of IRs across shifts were made by computing incidence rate ratios (IRRs) and their 95% confidence intervals (CIs). Sick leave occurred at a higher rate on the night shift (4.37 per 10,000 person-hours) compared with either day (1.55 per 10,000 person-hours) or afternoon (1.96 per 10,000 person-hours) shifts. The association between shiftwork and sickness absence depended on body mass index (BMI). For overweight individuals (BMI≥25 kg/m2), the covariate-adjusted incidence rate of sick leave (≥1 day) was twice as large for night-shift officers compared with those working on the day (IRR=2.29, 95% CI: 1.69-3.10) or afternoon (IRR=1.74, 95% CI: 1.29-2.34) shift. The IR of three or more consecutive days of sick leave was 1.7 times larger for those working on night shift (IRR=1.65, 95% CI: 1.17-2.31) and 1.5 times larger for those working on afternoon shift (IRR=1.50, 95% CI: 1.08-2.08) compared with day shiftworkers. For subjects with normal BMI (<25 kg/m2), the incidence rates of sick leave did not differ significantly across shifts. In conclusion, shiftwork is independently associated with sickness absence, with officers who work the night shift having elevated incidence of sick leave. In addition, overweight officers who work the night shift may be at additional risk for sickness absence.

Work-related mechanical risk factors for long-term sick leave: a prospective study of the general working population in Norway

BACKGROUND

The overall evidence for work-related mechanical exposures as risk factors for long-term sick leave (LTSL) in the general working population is limited.

METHODS

The study cohort was randomly drawn from the general population in Norway, aged 18-69 years (n = 12 255, response at baseline = 60.9%). Eligible respondents were interviewed in 2009 and were registered with an active employee relationship of at least 100 actual working days in 2009 and 2010 (n = 6758). The outcome of interest was medically confirmed LTSL ≥40 working days during 2010.

RESULTS

In total, 9.4% (635 individuals) were classified with LTSL during 2010. The risk of LTSL was higher in women, employees with fewer years of education, regular smokers, employees with chronic health complaints and employees with LTSL during 2009. After adjusting for these factors, we estimated that 24.6% of LTSL cases were attributable to work-related mechanical exposure. Mechanical risk factors were neck flexion, hand/arm repetition, standing, working with upper body bent forward and awkward lifting. The odds ratio for highest exposure levels ranged from 1.32 (95% confidence interval 1.04-1.69) for standing to 2.15 (95% confidence interval 1.24-3.73) for awkward lifting. A test for trend was statistically significant for all contributing factors (P ≤ 0.05), except standing. No psychosocial factors acted as major confounders related to any of the mechanical risk factors.

CONCLUSION

This study underlines the importance of work-related mechanical exposures as risk factors for LTSL in the general working population. An exposure-response relationship was indicated for 5 of the 10 factors evaluated.

International variation in absence from work attributed to musculoskeletal illness: findings from the CUPID study

OBJECTIVES

To quantify the variation in rates of absence due to musculoskeletal pain across 47 occupational groups (mostly nurses and office workers) from 18 countries, and to explore personal and group-level risk factors that might explain observed differences.

METHODS

A standardised questionnaire was used to obtain information about musculoskeletal pain, sickness absence and possible risk factors in a cross-sectional survey of 12 416 workers (92-1017 per occupational group). Additionally, group-level data on socioeconomic variables, such as sick pay and unemployment rates, were assembled by members of the study team in each country. Associations of sickness absence with risk factors were examined by Poisson regression.

RESULTS

Overall, there were more than 30-fold differences between occupational groups in the 12-month prevalence of prolonged musculoskeletal sickness absence, and even among office workers carrying out similar occupational tasks, the variation was more than tenfold. Personal risk factors included older age, lower educational level, tendency to somatise, physical loading at work and prolonged absence for non-musculoskeletal illness. However, these explained little of the variation between occupational groups. After adjustment for individual characteristics, prolonged musculoskeletal sickness absence was more frequent in groups with greater time pressure at work, lower job control and more adverse beliefs about the work-relatedness of musculoskeletal disorders.

CONCLUSIONS

Musculoskeletal sickness absence might be reduced by eliminating excessive time pressures in work, maximising employees' responsibility and control and providing flexibility of duties for those with disabling symptoms. Care should be taken not to overstate work as a cause of musculoskeletal injury.