Characterization of Occupational Lifting Patterns with Exposure Variation Analysis. Cross-sectional Workplace Study among Blue-Collar Workers.

OBJECTIVES: To investigate and characterize the influence of sex, age, muscle strength, and cardiovascular fitness on manual lifting patterns using exposure variation analysis (EVA) during a full working day among blue-collar workers. METHODS: Muscular activity (surface electromyography [sEMG]) of the thigh, low-back, and shoulder was measured throughout the working day in 173 employees with manual lifting tasks from 14 workplaces. Relative sEMG loading was expressed as % of maximal voluntary contraction (MVC). As an additional and more practically oriented analysis, calibration of load from standardized box lifts (5, 10, 20, and 30 kg) identified corresponding sEMG values in kg. Using an EVA 'lifting periods' of [1 to 5, >5 to 10, >10 to 20, >20 to 30, and >30] kg in time intervals [0 to 0.5, >0.5 to 1, >1 to 2, >2 to 5, >5 to 10, and >10] s were identified. Arm elevation and back inclination were measured using accelerometers. RESULTS: Females and older workers (≥50 years) primarily used the thighs for lifting and were exposed to more frequent thigh muscle 'lifting periods' of varying duration and load and performed more thigh lifts >30 kg and >60% of MVC compared with males and younger workers (P < 0.05). Females had less brief shoulder lifting periods and more work with bent back >30° than the males (P < 0.05), whereas stronger workers performed more work with elevated arm >60° and >90° than workers with low muscle strength (P < 0.05). However, besides a single difference where workers with lower cardiovascular fitness were exposed to more light (1-5 kg) and moderate duration (5-10 s) trapezius loading, the number of lifting periods was not affected by muscle strength nor cardiovascular fitness (P > 0.05). CONCLUSIONS: This EVA demonstrated sex- and age-related differences in exposure to lifting periods involving shoulder and thigh muscles.

Factors associated with high physical exertion during manual lifting: Cross-sectional study among 200 blue-collar workers.

BACKGROUND: High physical exertion during work is a risk factor for back pain and long-term sickness absence. OBJECTIVE: To investigate which factors are associated with physical exertion during manual lifting. METHODS: From 14 workplaces across Denmark, 200 blue-collar workers reported perceived physical exertion (Borg-CR10) during manual lifting from floor to table height of 5, 10, 20 and 30 kg at the beginning and end of the working day. The workers also responded to a questionnaire and went through testing of isometric back muscle strength. Associations were modelled using logistic regression analysis controlled for various confounders. The outcome was dichotomized into low (0-4) and high (5-10) physical exertion. RESULTS: Gender (OR 8.57 [95% CI 4.46-16.46] for women), load (OR 4.22 [95% CI 3.58-4.97] for each 5-kg increase), back muscle strength (OR 0.43 [95% CI 0.23-0.83] for high), and back pain intensity (OR 2.80 [95% CI 1.43-5.48] for high) were associated with high perceived physical exertion. Age, smoking, Body Mass Index (BMI), and time of the day were not associated with physical exertion. CONCLUSIONS: Gender, load, back muscle strength and back pain influence physical exertion during manual lifting in blue-collar workers. These factors should be considered when planning work with manual lifting for individual workers.

A cohort study on self-reported role stressors at work and poor sleep: does sense of coherence moderate or mediate the associations?

AIM: The aim of the present study was to examine the bidirectional associations between subjective role ambiguity and role conflicts at work, respectively, and self-reported sleep 2 years later. In addition, we also examine whether sense of coherence (SOC) moderate or mediate the association between role stressors and poor sleep and between poor sleep and role stressors. METHODS: We used questionnaire data collected in 2006 and 2008 from the Workplace Bullying and Harassment cohort. In 2006, 3363 responded to the questionnaire and in 2008 1671 responded. In total, 1569 participants responded in both 2006 and 2008 to the questions on role stressors (in terms of role ambiguity and role conflicts at work) and sleep problems in both 2006 and 2008. Sleep problems were assessed with the awakening index (AWI) and the disturbed sleep index (DSI). Moderation and mediation analyses of the association were estimated using structural equation modelling. RESULTS: We found a prospective association between role stressors and sleep problems [beta values were 0.07 (95% CI 0.03-0.11) and 0.05 (CI 0.01-0.10) for DSI and AWI, respectively] when adjusting for sleep problems at baseline, age, sex, and life style factors (i.e. alcohol, smoking, and leisure time physical activity). SOC moderated the association showing that participants with lower SOC scores who reported higher role ambiguity reported sleep problems to a higher extent than participants with high SOC scores. SOC also mediated the association between role stressors and sleep problems. We also found support for sleep problems at baseline and role stressors 2 years later [DSI 0.04 (CI 0.00-0.08) and 0.15 (CI 0.09-0.21)] for role ambiguity and role conflicts, respectively. Similar results were observed for AWI. CONCLUSION: Subjective role stressors were prospectively associated with sleep problems. Yet, sleep problems could also prospectively predict subjective role stressors (i.e. reverse causation). The analyses also showed that SOC may be regarded as both a mediating and a moderating factor of the association between subjective role conflicts and poor sleep. We found that SOC moderated the prospective association so participants with low SOC report more sleep problems with subjective role conflicts compared to participants with high SOC. Finally, we also found SOC mediated the prospective association between subjective role stressors and sleep problems and the reverse association.

Tumor suppressor menin is required for subunit-specific nAChR α5 transcription and nAChR-dependent presynaptic facilitation in cultured mouse hippocampal neurons.

In the central nervous system (CNS), cholinergic transmission induces synaptic plasticity that is required for learning and memory. However, our understanding of the development and maintenance of cholinergic circuits is limited, as the factors regulating the expression and clustering of neuronal nicotinic acetylcholine receptors (nAChRs) remain poorly defined. Recent studies from our group have implicated calpain-dependent proteolytic fragments of menin, the product of the MEN1 tumor suppressor gene, in coordinating the transcription and synaptic clustering of nAChRs in invertebrate central neurons. Here, we sought to determine whether an analogous cholinergic mechanism underlies menin's synaptogenic function in the vertebrate CNS. Our data from mouse primary hippocampal cultures demonstrate that menin and its calpain-dependent C-terminal fragment (C-menin) regulate the subunit-specific transcription and synaptic clustering of neuronal nAChRs, respectively. MEN1 knockdown decreased nAChR α5 subunit expression, the clustering of α7 subunit-containing nAChRs at glutamatergic presynaptic terminals, and nicotine-induced presynaptic facilitation. Moreover, the number and function of glutamatergic synapses was unaffected by MEN1 knockdown, indicating that the synaptogenic actions of menin are specific to cholinergic regulation. Taken together, our results suggest that the influence of menin on synapse formation and synaptic plasticity occur via modulation of nAChR channel subunit composition and functional clustering.

Two Swedish screening instruments for exhaustion disorder: cross-sectional associations with burnout, work stress, private life stress, and personality traits.

AIMS: To examine the relationships of two screening instruments recently developed for assessment of exhaustion disorder (ED) with some other well-known inventories intended to assess ED-related concepts and self-reports of job demands, job control, job support, private life stressors, and personality factors. METHODS: A cross-sectional population sample ( n = 1355) completed: the Karolinska Exhaustion Disorder Scale (KEDS), Self-reported Exhaustion Disorder Scale (s-ED), Shirom-Melamed Burnout Questionnaire (SMBQ), Utrecht Work Engagement Scale (UWES-9), Job Content Questionnaire (JCQ), Big Five Inventory (BFI), and items concerning family-to-work interference and stress in private life. RESULTS: Compared to participants without any indication of ED, participants classified as having ED on KEDS or s-ED had higher scores on all four SMBQ subscales, lower scores on the UWES-9 subscales vigor and dedication, higher JCQ job demands scores, lower JCQ job support scores, higher degrees of family-to-work interference and stress in private life, and higher BFI neuroticism and openness scores. In addition, participants classified as having ED on KEDS had lower scores on the UWES-9 absorption subscale, the JCQ job control scale, and lower BFI extraversion, agreeableness and conscientiousness scores, compared to the subgroup not classified as having ED. CONCLUSIONS: As expected, we observed an overall pattern of associations between the ED screening inventories KEDS and s-ED and measures of burnout, work engagement, job demands-control-support, stress in private life, family-to-work interference, and personality factors. The results suggest that instruments designed to assess burnout, work engagement, and ED share common ground, despite their conceptual differences.

Exposure to negative acts and risk of turnover: a study of a register-based outcome among employees in three occupational groups.

PURPOSE: To investigate whether self-reported exposure to negative acts in the workplace (bullying and threats of violence) predicted turnover in three occupational groups (human service and sales workers, office workers and manual workers). METHODS: Survey data on 2766 respondents were combined with data from a national labour force register to assess turnover. Mixed effects logistic regression analysis was used to examine the association between self-reported exposure to negative acts at baseline and risk of turnover after a 1-year follow-up. RESULTS: We found no significant associations between exposure to negative acts (bullying and threats of violence) and risk of turnover. When participants were stratified by occupational group and analyses were adjusted for age, gender, tenure and psychosocial working conditions, we found that exposure to bullying predicted risk of turnover in office workers (OR 2.03, 95 % CI 1.05-3.90), but neither in human service and sales workers, nor in manual workers. The association in office workers lost statistical significance when additionally adjusted for depressive symptoms (OR 1.77, 95 % CI 0.90-3.49). However, in a sensitivity analysis in which we used a 2-year (instead of a 1-year) follow-up period the association between bullying and turnover remained statistically significant in office workers even after adjusting for depressive symptoms (OR 2.10, 95 % CI 1.17-3.76). We found no statistically significant associations between threats of violence and risk of turnover in the stratified analyses. CONCLUSION: Exposure to bullying predicted risk of turnover among office workers but not among human service and sales workers and among manual workers. Threats of violence were not associated with turnover in any occupational group.

The Lund University Checklist for Incipient Exhaustion-a cross-sectional comparison of a new instrument with similar contemporary tools.

BACKGROUND: Stress-related health problems (e.g., work-related exhaustion) are a societal concern in many postindustrial countries. Experience suggests that early detection and intervention are crucial in preventing long-term negative consequences. In the present study, we benchmark a new tool for early identification of work-related exhaustion-the Lund University Checklist for Incipient Exhaustion (LUCIE)-against other contextually relevant inventories and two contemporary Swedish screening scales. METHODS: A cross-sectional population sample (n = 1355) completed: LUCIE, Karolinska Exhaustion Disorder Scale (KEDS), Self-reported Exhaustion Disorder Scale (s-ED), Shirom-Melamed Burnout Questionnaire (SMBQ), Utrecht Work Engagement Scale (UWES-9), Job Content Questionnaire (JCQ), Big Five Inventory (BFI), and items concerning work-family interference and stress in private life. RESULTS: Increasing signs of exhaustion on LUCIE were positively associated with signs of exhaustion on KEDS and s-ED. The prevalence rates were 13.4, 13.8 and 7.8 %, respectively (3.8 % were identified by all three instruments). Increasing signs of exhaustion on LUCIE were also positively associated with reports of burnout, job demands, stress in private life, family-to-work interference and neuroticism as well as negatively associated with reports of job control, job support and work engagement. CONCLUSIONS: LUCIE, which is intended to detect pre-stages of ED, exhibits logical and coherent positive relations with KEDS and s-ED as well as other conceptually similar inventories. The results suggest that LUCIE has the potential to detect mild states of exhaustion (possibly representing pre-stages to ED) that if not brought to the attention of the healthcare system and treated, may develop in to ED. The prospective validity remains to be evaluated.

Are changes in workplace bullying status related to changes in salivary cortisol? A longitudinal study among Danish employees.

OBJECTIVES: This study aims to investigate whether incident workplace bullying and its dicontinuance is related to subsequent change in morning and evening saliva cortisol concentrations. METHODS: Participants came from two Danish cohort studies, the PRISME cohort (n=4489) and the Workplace Bullying and Harassment Cohort (n=3707). At baseline and follow-up exposure to bullying was measured by a single question on bullying (preceded by a definition). Two saliva samples to measure cortisol were collected during a work-day (30 min after awakening and at 8 p.m.). All participants responding to the item on workplace bullying, giving saliva samples and participated at both baseline and follow-up were included. The reference group consisted of non-bullied respondents at both baseline and follow-up. Multilevel mixed-effects linear regressions were used to test for changes in salivary cortisol after newly onset of and discontinuance of workplace bullying. All analyses were adjusted for the potentially confounding effect of differences from baseline to follow-up in education, smoking, alcohol consumption, body mass index, cohort, sampling waves, time of awakening, and time of sampling. RESULTS: We found no indication of statistically significant difference in saliva cortisol, neither when participants changed their self-labelling from not bullied at baseline to being bullied at follow-up, nor when they at follow-up two years later reported discontinuance of bullying. CONCLUSION: This longitudinal study on the impact of changes in bullying status on change in cortisol levels showed consistent lack of associations with onset and discontinuance of workplace bullying.

Central Sensitization and Perceived Indoor Climate among Workers with Chronic Upper-Limb Pain: Cross-Sectional Study.

Monitoring of indoor climate is an essential part of occupational health and safety. While questionnaires are commonly used for surveillance, not all workers may perceive an identical indoor climate similarly. The aim of this study was to evaluate perceived indoor climate among workers with chronic pain compared with pain-free colleagues and to determine the influence of central sensitization on this perception. Eighty-two male slaughterhouse workers, 49 with upper-limb chronic pain and 33 pain-free controls, replied to a questionnaire with 13 items of indoor climate complaints. Pressure pain threshold (PPT) was measured in muscles of the arm, shoulder, and lower leg. Cross-sectional associations were determined using general linear models controlled for age, smoking, and job position. The number of indoor climate complaints was twice as high among workers with chronic pain compared with pain-free controls (1.8 [95% CI: 1.3-2.3] versus 0.9 [0.4-1.5], resp.). PPT of the nonpainful leg muscle was negatively associated with the number of complaints. Workers with chronic pain reported more indoor climate complaints than pain-free controls despite similar actual indoor climate. Previous studies that did not account for musculoskeletal pain in questionnaire assessment of indoor climate may be biased. Central sensitization likely explains the present findings.

The relationship between self-efficacy and help evasion.

OBJECTIVE: To examine the relationship between self-efficacy and not wanting help to change health behaviors. METHOD: All employees in the Danish police department were invited to respond to an electronic questionnaire. All respondents expressing a desire to change health behaviors in relation to smoking (n = 845), alcohol (n = 684), eating (n = 4431), and physical activity (n = 5179) and who subsequently responded to questions on self-efficacy were included. RESULTS: Both the bivariate and multiple regression analyses showed that all four specific self-efficacy scores were positively related to reporting that one did not want help. CONCLUSION: A high belief in one's own ability to change lifestyle behaviors in relation to smoking, alcohol, eating, and physical activity may lead to avoidance of help offers in a workplace setting.

Patient transfers and assistive devices: prospective cohort study on the risk for occupational back injury among healthcare workers.

OBJECTIVES: This prospective cohort study investigates work-related risk factors for occupational back injury among healthcare workers. METHODS: The study comprised 5017 female healthcare workers in eldercare from 36 municipalities in Denmark who responded to a baseline and follow-up questionnaire in 2005 and 2006, respectively. Using logistic regression, the odds for occupational back injury (ie, sudden onset episodes) in 2006 from patient transfers in 2005 was modeled. RESULTS: In the total study population, 3.9% experienced back injury during follow-up, of which 0.5% were recurrent events. When adjusting for lifestyle (body mass index, leisure-time physical activity, smoking), work-related characteristics (seniority and perceived influence at work), and history of back pain and injury, daily patient transfers increased the risk for back injury (trend, P=0.03): odds ratio (OR) 1.75 [95% confidence interval (95% CI) 1.05-2.93] for 1-2 transfers per day, OR 1.81 (95% CI 1.14-2.85) for 3-10 transfers per day, and OR 1.56 (95% CI 0.96-2.54) for >10 transfers per day, referencing those with <1 patient transfer on average per day. The population attributable fraction of daily patient transfer for back injury was estimated to be 36%. Among those with daily patient transfer (N=3820), using an assistive device decreased the risk for back injury for "often" and "very often" use [OR 0.59 (95% CI 0.36-0.98) and OR 0.62 (95% CI 0.38-1.00), respectively] referencing those who "seldom" use assistive devices. CONCLUSION: Daily patient transfer was associated with increased risk for back injury among healthcare workers. Persistent use of an assistive device was associated with reduced risk for back injury among healthcare workers with daily patient transfers.

Help Preferences Among Employees Who Wish to Change Health Behaviors.

OBJECTIVE: To examine the help preferences of employees in the Danish police who had acknowledged that they wished to change health behaviors. In addition, we explored whether preferences varied with age, gender, chronic health concerns, positive expectations of good health, and past experiences of in-house health promotion services (i.e., wellness service). METHODS: Respondents to an electronic questionnaire who acknowledged wishing to change health behaviors in relation to smoking (n = 845), alcohol (n = 684), eating (n = 4,431), and physical activity (n = 5,179) were asked to choose up to three help alternatives on a predefined list. RESULTS: In descending order, smokers preferred help from nicotine gum, no help, and help and support from family and friends. Alcohol consumers preferred no help or help and support from family and friends or "other" forms. Employees who wanted to change eating habits preferred a free fruit bowl, free nutritional guidance, and healthy food at work. Employees who wanted to change physical activity patterns preferred exercise at work, offers of free exercise, and exercise in a social/collegial context. CONCLUSION: Wishing to change health behaviors is not always accompanied by perceiving a need for assistance. The no-help option was selected fairly frequently and mostly in relation to alcohol and smoking. A fruit bowl was the most preferred option for help, followed by exercise at work and free exercise. Help from traditional health services was ranked low, possibly reflecting that they are primarily viewed as a solution for stopping disease rather than promoting health.

Perceived physical exertion during healthcare work and risk of chronic pain in different body regions: prospective cohort study.

PURPOSE: To estimate the risk of developing chronic musculoskeletal pain in different body regions from varying degrees of perceived physical exertion during healthcare work. METHODS: Prospective cohort study among 4,977 Danish female healthcare workers responding to a baseline and follow-up questionnaire in 2005 and 2006, respectively. Using multi-adjusted logistic regression analysis, the risk of developing chronic pain (>30 days last year) at follow-up in the low back, neck/shoulder, and knees-among those without pain (0 days last year) in these respective body regions at baseline-from moderate and strenuous (reference: light) perceived physical exertion during healthcare work was modeled. RESULTS: Adjusted for age, BMI, tenure, smoking status, and leisure physical activity, strenuous perceived physical exertion during healthcare work increased the risk of chronic low back pain (OR 3.16, 95 % CI 1.79-5.57) and chronic knee pain (OR 1.87, 95 % CI 1.19-2.94) at follow-up among those without pain in these respective body regions at baseline. With additional adjustment for psychosocial work conditions, only the risk of developing chronic low back pain from strenuous physical exertion remained significant (OR 1.99, 95 % CI 1.02-3.88). Strenuous physical exertion was not a risk factor for chronic neck pain, and moderate physical exertion was not a risk factor for chronic pain in any of the body regions. CONCLUSION: Strenuous perceived physical exertion during healthcare work is a risk factor especially for developing chronic pain in the low back. The possible preventive effect of reducing strenuous physical exertion should be tested in randomized controlled trials.

Perceived physical exertion during healthcare work and prognosis for recovery from long-term pain in different body regions: Prospective cohort study.

BACKGROUND: The prevalence of musculoskeletal pain is high among healthcare workers. Knowledge about risk factors at work is needed to efficiently target preventive strategies. This study estimates the prognosis for recovery from long-term musculoskeletal pain in different body regions among healthcare workers with different levels of perceived physical exertion during healthcare work. METHODS: Prospective cohort study among 4,977 Danish female healthcare workers responding to a baseline and follow-up questionnaire in 2005 and 2006, respectively. We defined long-term pain, short-term pain and pain-free as > 30, 1-30 and 0 days with pain during the last year, and included in the analyses only those with long-term pain at baseline in the low back (N=1,089), neck/shoulder (N=1,400) and knees (N = 579), respectively. Using cumulative logistic regression analysis, the prognosis for recovering from long-term pain at baseline to short-term pain or pain-free at follow-up in the respective body regions when experiencing moderate or light (reference: strenuous) physical exertion during healthcare work was modeled. RESULTS: Among those with long-term pain at baseline 34% (low back), 29% (neck/shoulders), and 29% (knees) recovered to short-term pain at follow-up and 7% (low back), 8% (neck/shoulders), and 17% (knees) recovered to being pain-free. After adjusting for potential confounders (age, BMI, tenure, smoking status, leisure physical activity and psychosocial work conditions), light perceived physical exertion during healthcare work was associated with improved prognosis for recovery from long-term pain in the low back (OR 1.42, 95% CI 1.01 - 1.99) and neck/shoulders (OR 1.89, 95% CI 1.43 - 2.50), but not in the knees. Moderate physical exertion was not associated with improved prognosis for recovery from long-term pain for any of the body regions. CONCLUSION: In the present study, healthcare workers with light perceived physical exertion during healthcare work had the best prognosis for recovery from long-term pain in the low back and neck/shoulders. This suggests that efforts to reduce perceived exertion during work may improve recovery from chronic pain.

Dose-response relation between perceived physical exertion during healthcare work and risk of long-term sickness absence.

OBJECTIVE: An imbalance between physical work demands and physical capacity of the worker may be a risk factor for poor health. Perceived physical exertion provides information about the individual perception of the work demands relative to the capacity to perform the work. This study estimates the risk for long-term sickness absence (LTSA) from perceived physical exertion among healthcare workers. METHODS: This prospective cohort study comprises 8592 Danish healthcare workers who responded to a baseline questionnaire in 2004-2005 and subsequently were followed for one year in the Danish Register for Evaluation of Marginalization (DREAM), a national register of social transfer payments. Using Cox regression hazard ratio (HR) analysis, controlled for age, gender, body mass index (BMI), smoking, tenure, leisure-time physical activity, psychosocial working conditions, and LTSA during one year prior to baseline, we modeled risk estimates of moderate and strenuous (reference: light) perceived physical exertion during healthcare work for onset of LTSA (receiving sickness absence compensation for ≥8 consecutive weeks) during 1-year follow-up. RESULTS: At baseline, 35.1%, 39.4%, and 25.5% of the healthcare workers experienced, respectively, light, moderate, and strenuous physical exertion during healthcare work. During follow-up, the 12-month prevalence of LTSA was 4.6%, 6.4%, and 8.9%, respectively, in these three exertion groups. A dose-response pattern between physical exertion and the risk for LTSA was found (trend test P<0.0001). In the multi-adjusted model, the risk for LTSA was 1.31 [95% confidence interval (95% CI) 1.04-1.64] for healthcare workers reporting moderate physical exertion and 1.57 (95% CI 1.23-2.01) for those reporting strenuous physical exertion, referencing those reporting light physical exertion during healthcare work. CONCLUSION: Moderate and strenuous perceived physical exertion during healthcare work increases - in a dose-response manner - the risk for LTSA. The possible preventive effect of balancing work demands with the capacity of the worker, to thereby avoid excessive physical exertion, should be tested in randomized controlled trials.

Adult survivors of childhood acute lymphoblastic leukaemia with GH deficiency have normal self-rated quality of life but impaired neuropsychological performance 20 years after cranial irradiation.

OBJECTIVE: Cranial radiotherapy (CRT) was, until recently, important for achieving long-term survival in acute lymphoblastic leukaemia (ALL). Because survival rates have improved markedly, the long-term complications, such as GH deficiency (GHD) and neuropsychological impairment, have become increasingly important. DESIGN AND PATIENTS: The level of self-reported quality of life and neuropsychological functioning was investigated in 44 adults (21 women) with a median age of 25 years who had been treated for childhood onset (CO) ALL with CRT (median 24 Gy). Comparison was made with matched population controls. A subset of patients with GHD was evaluated for neuropsychological functioning after 1 year of GH treatment. RESULTS: Compared to controls, the patients had significantly lower performance in neuropsychological tests. Early age at treatment had a significant negative impact on neuropsychological performance in adulthood. No relationship was found between dose of CRT, time since treatment of ALL or gender and neuropsychological performance. Compared to controls, the patients did not show a poor quality of life or a lowered availability of social interactions or social networks; however, significantly more patients were living alone or with their parents. After GH testing, the patients were all considered GH deficient or insufficient, but no relationship was observed between stimulated peak GH secretion and neuropsychological performance. Treatment with GH for 1 year in a subgroup of the patients did not improve their neuropsychological performance. CONCLUSIONS: This study showed that adults treated with CRT for CO ALL had GHD and significantly impaired neuropsychological performance, although self-reported quality of life was not affected. The effect of GH treatment in this patient group has to be further elucidated.