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Among workers performing hand-intensive tasks, musculoskeletal disorders in the upper extremities are more frequent in women than in men. However, risk assessments are generally not sex-specific, and it is not known whether exposures in regular work differ between females and males. The aim of this study was to compare measured wrist joint velocity and muscle activity between men and women performing identical tasks. Participants (28 female–male pairs) performed one of eighteen hand-intensive on-site tasks. Wrist velocity was measured using inertial units. Forearm muscle activity was measured via surface electromyography and normalized to maximal voluntary electrical activation (MVE). The 10th, 50th, and 90th percentiles and time in muscle recovery (< 0.5 %MVE) were computed. Between-sex differences were tested using the Wilcoxon signed-rank test. Wrist angular velocities did not significantly differ between sexes in any percentile (all p > 0.374). The muscle activity was significantly higher in female workers (p < 0.001–0.004), ranging from 1.3 to 2.8 times higher, and they spent less time in muscle recovery (p < 0.001). In hand-intensive tasks involving women and men, risk assessments should prioritize assessments of women to ensure protection against work-related musculoskeletal disorders for all workers.

Objective: To measure and determine the occupational cardiovascular workload and cardiovascular fitness among older employees (50 +) in four physically demanding occupational groups.

Methods: Health investigations, including aerobic capacity, were performed on 120 construction and kitchen workers, cleaners, and assistant nurses. Cardiovascular load was assessed over three working days using heart rate (HR) measurements. Data was processed for average loads (HR and Relative HR reserve (%HRR)) and measures describing variations in loads, such as time spent in different heart rate intensities.

Results: Participants’ mean age was 57 (SD 4.1) years, and 63% of the participants were female. The mean %HRR over occupational groups was 24.9% (SD 6.8). Of the participants, 43% had an average cardiovascular load above 24.5%HRR and 11% over 33%HRR. Depending on the work sector, 22–37% of the worktime was spent in intensities over 30%HRR, and 2–4% was spent in cardiovascular intensities over 50%HRR. The average VO2max was 33.2 (SD 8.2) ml/kg/min for all, for men 39.0 (SD 7.0), and for women 29.8 (SD 6.9).

Conclusion: We found a high mean cardiovascular load at work among the senior workers in all four work sectors, but low proportions of the worktime were spent in high intensity levels. Despite a high mean cardiovascular load at work, a high proportion of the workers had low cardiovascular fitness. Given the possible negative effects of occupational physical activity and to meet future demographic challenges, future interventions should aim to reduce physical loads and increase physical fitness in the workforce.

Background: Contrary to leisure-time physical activity, high levels of occupational physical activity (OPA) have been linked to cardiovascular disease and mortality. Many occupations in the construction industry are known to have high levels of OPA.Aims This study investigated OPA and stroke mortality risk among 299 382 Swedish male construction workers.

Methods: OPA was derived from job titles and categorized as low, medium or high, and stroke mortality was ascertained via the Swedish National Cause of Death Register. The average follow-up was 24 years resulting in a total of 6.9 million person-years, during which 4606 participants died from stroke. Relative risks were estimated with robust Poisson regressions and adjusted for age, calendar year, body mass index and smoking.

Results: The relative risk for overall stroke mortality was higher in the medium and high OPA groups compared to the low OPA group [1.15 (1.04, 1.27) and 1.13 (1.04, 1.23), respectively], with no clear dose-response association. Age-stratified analyses showed that higher OPA increased stroke mortality risk in participants between 70 and 89 years. Participants with high versus low OPA had a higher risk of ischaemic stroke mortality [1.15 (1.01, 1.31)].

Conclusions: Construction workers with high OPA have a slight increase in overall stroke mortality, mainly after retirement. Contrary to leisure-time physical activity, high levels of occupational physical activity have been linked to an increased risk of cardiovascular disease and mortality. Construction workers in this study with medium and high occupational physical activity had higher stroke mortality than those with low occupational physical activity. However, there was no difference in stroke mortality between those with high and medium occupational physical activity.

Background: Exposure assessment of wrist velocity and muscular activity in hand-intensive work are pillars in risk assessment of hand-intensive work in workplaces. Workers who are engaged in hand-intensive work, such as assembly and food processing, have an increased risk for musculoskeletal disorders (MSDs) and carpal tunnel syndrome (CTS) diagnosis. Foremost, the MSD and CTS prevalences are notably higher in females. We lack knowledge of whether wrist velocity and muscular activity are the same in women and men in identical tasks. This might lead to over- or underrating of risk in males and females, hence missing out on optimal risk-reducing actions to sufficiently protect women and men. Risk assessment which sufficiently protects both sexes from ill-health, supports a sustainable working life for women and men equally.  Therefore, it is essential to investigate if exposure is the same in women and men in identical tasks, in regular work. 

Purpose: We aimed to investigate if wrist velocity and muscular activity are the same in females and males in identical hand-intensive tasks. 

Methods. Participants comprised 28 female-male pairs (56 individuals) who worked in one of 18 different hand-intensive occupational tasks in their regular workplace. Wrist angular velocity was measured with inertial measurement units placed on the dorsal hand and distal forearm, and characterized by the 50th percentile (median). Forearm muscular activity was measured in the flexor carpi radialis (FCR) and extensor carpi radialis (ECR) with surface electromyography. This was normalized to the maximal voluntary electrical activation (MVE). The 50th percentile (median) was computed, and also the time spent in muscular recovery (<0.5 %MVE). To test between-sex differences, the Wilcoxon signed rank test was used. 

Results: Median wrist angular velocities did not significantly differ between sexes (p= 0.374). The muscular activity for FCR and ECR was significantly higher in females than in males, double compared to males (FCR p=0.001, ECR p=0.003). The time spent in muscular recovery was less in females (than in males (FCR p < 0.001, ECR p=0.002), for both FCR (females 0% of the time; males 8.1%) and ECR (0%; 0.2%).

Conclusion: In regular identical hand-intensive work tasks, females' muscle activity was higher, and muscular recovery time lower than that of males. 

Implication: These findings have a direct impact on risk assessments in hand-intensive work. In jobs where female workers are involved, the risk assessment should be based on females. When using observational risk assessment methods, the risk criteria level should ensure a safe level for women to execute the job with a low risk of acquiring work-related musculoskeletal disorders.

BACKGROUND: This study examined whether sick leave due to severe stress (stress leave) and duration of leave are associated with future cancer risk.

METHODS: We conducted a matched case-control study using complete-population data from Swedish national registers (2005 to 2018), including 516,678 primary cancer cases and 2,357,433 matched controls. Odds ratios (OR) were calculated by conditional logistic regression and adjusted for pre-specified confounders.

RESULTS: Stress leave of any duration, reported to the Swedish Social Insurance Register, was associated with a slightly increased cancer risk, with the highest risk estimate for 1-30 versus 0 days (adjusted OR 1.05, 95% CI 1.02-1.09). In men, a clear exposure-response trend was present. We observed increased risks of prostate cancer (adjusted OR for > 90 days: 1.10, 95% CI 1.01-1.20) and cervical cancer (adjusted OR for > 90 days: 1.11, 95% CI 1.05-1.17, including cancer in situ). In etiology-based analyses, a positive association was found for smoking-related cancers, and the risk relationship for non-cervical HPV-related cancers was similar to that for cervical cancer. Risk estimates were above one for several types of stress in relation to overall cancer risk, including an exposure-response trend for acute stress reactions (p-trend 4.0 × 10-4) but a null association for post-traumatic stress disorder.

CONCLUSIONS: Stress leave was associated with a modestly higher risk of cancer overall and prostate and cervical cancers specifically. Regardless of whether the link is biological or reflective of lifestyle mediators or for cervical cancer, lower participation in screening, these findings suggest a potential relevance of severe stress for cancer prevention.

Background: Stress-induced exhaustion disorder (SED) is the most common reason for long-term sick leave in Sweden and the recovery process may be long and troublesome. This study explores the symptoms of burnout, depression and anxiety among patients with SED 10 years after termination of a multimodal rehabilitation program. Another aim of the study was to investigate work situation, work functioning, and any remaining exhaustion and sleeping disorders among those who were gainfully employed at the 10-year follow-up.

Methods: This longitudinal study included 107 patients (91 women and 16 men), who had been diagnosed with SED 10 years prior to the study. After establishing the diagnosis they all underwent and completed an multimodal rehabilitation program. Data on symptoms of burnout, anxiety and depression were collected before and after the multimodal rehabilitation program, and at follow-ups after additional 1 year and an additional 10 years. At the 10-year follow-up, work situation, work functioning, and symptoms of exhaustion and sleep disorders were assessed in those who were gainfully employed (89 patients).

Results: Symptoms of burnout, anxiety, and depression remained stable from the 1- to the 10-year follow-up after completed rehabilitation. Among participants who were gainfully employed, 73% had changed workplaces, and 31.5% had reduced their working hours. Common reasons for these changes were lack of energy or because they had chosen to prioritise their lives differently. Work functioning was rated as moderate, one third self-reported SED to some extent, and one fifth reported moderate-to-severe insomnia.

Conclusion: A relatively large proportion of former patients with SED have residual health problems 10 years after rehabilitation and some have not been able to return to full-time work. Preventive and early rehabilitative interventions with adjustments and measures at the organisational level are probably needed to achieve a more sustainable working life.

An accurate rating of hand activity and force is essential in risk assessment and for the effective prevention of work-related musculoskeletal disorders. However, it is unclear whether the subjective ratings of workers and observers correlate to corresponding objective technical measures of exposure. Fifty-nine workers were video recorded while performing a hand-intensive work task at their workplace. Self-ratings of hand activity level (HAL) and force (Borg CR10) using the Hand Activity Threshold Limit Value® were assessed. Four ergonomist observers, in two pairs, also rated the hand activity and force level for each worker from video recordings. Wrist angular velocity was measured using inertial movement units. Muscle activity in the forearm muscles flexor carpi radialis (FCR) and extensor carpi radialis (ECR) was measured with electromyography root mean square values (RMS) and normalized to maximal voluntary electrical activation (MVE). Kendall’s tau-b correlations were statistically significant between self-rated hand activity and wrist angular velocity at the 10th, 50th, and 90th percentiles (0.26, 0.31, and 0.23) and for the ratings of observers (0.32, 0.41, and 0.34). Significant correlations for force measures were found only for observer-ratings in five of eight measures (FCR 50th percentile 0.29, time > 10%MVE 0.43, time > 30%MVE 0.44, time < 5% −0.47) and ECR (time > 30%MVE 0.26). The higher magnitude of correlation for observer-ratings suggests that they may be preferred to the self-ratings of workers. When possible, objective technical measures of wrist angular velocity and muscle activity should be preferred to subjective ratings when assessing risks of work-related musculoskeletal disorders.

Background: To develop effective injury prevention approaches for work-related musculoskeletal disorders in hand-intensive work, accurate quantitative risk assessments of workers' hand activity and force level are essential. However, to what extent workers’ self-ratings and observers’ ratings of hand activity and force levels correlate to corresponding objective measures is not well known. 

Methods: Fifty-nine workers (29 women and 30 men) were video recorded performing a hand-intensive work task for 15 minutes in their regular work. Workers self-rated hand activity level and hand force level (Borg CR10), both being variables in the method Hand Activity Threshold Limit Value®. Furthermore, four observers, two woman–man pairs, rated each worker's hand activity and force levels from the video recordings. Workers’ wrist flexion angular velocity was measured using inertial movement units (IMUs) on the hand and distal forearm. The 10th, 50th, and 90th percentiles were computed. The muscle activity in the forearm muscles flexor carpi radialis and extensor carpi radialis was measured with electromyography (EMG, Delsys, Trigno).  Root-mean-square values (RMS) were computed and normalized to the RMS during maximal voluntary electrical activation (%MVE). The 50th percentile of %MVE and proportion of time >30%MVE in the work task were computed from the normalized EMG.

Results: Spearman correlations between self-rated hand activity and wrist angular velocity were 0.35, 0.38, and 0.28 at the 10th, 50th, and 90th percentiles, respectively. Corresponding correlations for observers’ ratings were 0.40, 0.56, and 0.45. All correlations were statistically significant.  None of the self-reported force levels were significantly correlated to muscle activity (50th and >30 %MVE).  Correlation between observer-reported force level and flexor carpi radialis activity was 0.40 and 0.56 of 50th and 30%MVE, respectively. Corresponding correlation between observer-reported force level and extensor carpi radialis activity was 0.37 for >30 %MVE. All observer-rated force levels were significantly correlated to muscle activity, except for 50th for extensor carpi radialis.

Conclusion:  Observer ratings correlated more strongly than self-ratings with technical wrist angular flexion velocity and muscular activity measures. If ratings are used, observers’ ratings should be preferred since they seem more valid than the workers’ own ratings. Overall, the correlations between ratings and technical measures were modest. This suggests that technical measures of wrist flexion angular velocity and muscular activity should be preferred for exposure assessment, when possible.