The relationship between quality of sleep and night shift rotation interval.

PubMed

Kim, Jae Youn; Chae, Chang Ho; Kim, Young Ouk; Son, Jun Seok; Kim, Ja Hyun; Kim, Chan Woo; Park, Hyoung Ouk; Lee, Jun Ho; Kwon, Soon Il; Kwon, Sun Il

2015-01-01

Shift work is closely related with workers' health. In particular, sleep is thought to be affected by shift work. In addition, shift work has been reported to be associated with the type or direction of shift rotation, number of consecutive night shifts, and number of off-duty days. We aimed to analyze the association between the night shift rotation interval and the quality of sleep reported by Korean female shift workers. In total, 2,818 female shift workers from the manufacturing industry who received an employee physical examination at a single university hospital from January to August in 2014 were included. Subjects were classified into three groups (A, B, and C) by their night shift rotation interval. The quality of sleep was measured using the Korean version of the Pittsburgh Sleep Quality Index (PSQI). Descriptive analysis, univariate logistic regression, and multivariate logistic regression were performed. With group A as the reference, the odds ratio (OR) for having a seriously low quality of sleep was 1.456 (95% CI 1.171-1.811) and 2.348 (95% CI 1.852-2.977) for groups B and C, respectively. Thus, group C with the shortest night shift rotation interval was most likely to have a low quality of sleep. After adjustment for age, obesity, smoking status, alcohol consumption, exercise, being allowed to sleep during night shifts, work experience, and shift work experience, groups B and C had ORs of 1.419 (95% CI 1.134-1.777) and 2.238 (95% CI 1.737-2.882), respectively, compared to group A. Our data suggest that a shorter night shift rotation interval does not provide enough recovery time to adjust the circadian rhythm, resulting in a low quality of sleep. Because shift work is influenced by many different factors, future studies should aim to determine the most optimal shift work model and collect accurate, prospective data.

The effect of bright light on sleepiness among rapid-rotating 12-hour shift workers.

PubMed

Sadeghniiat-Haghighi, Khosro; Yazdi, Zohreh; Jahanihashemi, Hassan; Aminian, Omid

2011-01-01

About 20% of workers in industrialized countries are shift workers and more than half of them work on night or rotating shifts. Most night workers complain of sleepiness due to lack of adjustment of the circadian rhythm. In simulated night-work experiments, scheduled exposure to bright light has been shown to reduce these complaints. Our study assessed the effects of bright light exposure on sleepiness during night work in an industrial setting. In a cross-over design, 94 workers at a ceramic factory were exposed to either bright (2500 lux) or normal light (300 lux) during breaks on night shifts. We initiated 20-minute breaks between 24.00 and 02.00 hours. Sleepiness ratings were determined using the Stanford Sleepiness Scale at 22.00, 24.00, 02.00 and 04.00 hours. Under normal light conditions, sleepiness peaked at 02:00 hours. A significant reduction (22% compared to normal light conditions) in sleepiness was observed after workers were exposed to bright light. Exposure to bright light may be effective in reducing sleepiness among night workers.

Shift work and sleep disorder among textile mill workers in Bahir Dar, northwest Ethiopia.

PubMed

Abebe, Y; Fantahun, M

1999-07-01

To assess the length and quality of sleep among shift workers at Bahir Dar textile mill. A cross sectional study using structured questionnaire that contained sociodemographic variables, duration of work, work schedule, number of sleeping hours, sleep disorders, and associated reasons for such disorders. A textile mill in Bahir Dar, northwest Ethiopia. Three-hundred ninety four random sample of production workers of the mill. Sleep disorders, and the impact of external and home environment on sleep. The mean duration of work in the factory was 25.4 +/- 7.1 years. Ninety-seven per cent of the study population work in a rotating eight hourly shift system. The mean number of hours a worker sleeps after a worked shift was 5.1 +/- 2.3. Two hundred thirty (58.4%) claimed to experience a sleep disorder. Sleep disturbance was significantly associated with rotating shift work, external environmental noise, and working in the spinning department. The majority of the workers in Bahir Dar textile mill experienced sleep disturbances as detailed in the study methodology.

Shift-work disorder and sleep-related environmental factors in the manufacturing industry.

PubMed

Taniyama, Yukari; Nakamura, Arisa; Yamauchi, Takenori; Takeuchi, Shouhei; Kuroda, Yoshiki

2015-03-01

The aim of this study was to examine the relationship between shift-work disorder (SWD) and environmental and somatic factors related to falling asleep among rapidly rotating shift workers in a manufacturing industry.A total of 556 male workers were recruited to complete a self-administered questionnaire regarding age, shift work experience, lifestyle, and family structure; the Epworth sleepiness scale (ESS); the Pittsburgh sleep quality index (PSQI); and the Horne and Ostberg questionnaire, a questionnaire for environmental and somatic factors related to falling asleep. We classified workers according to having SWD or not, and compared workers with SWD with those without this disorder in terms of all items covered in the aforementioned questionnaires. A total of 208 workers (62.8%) working rapidly rotating shifts were diagnosed with SWD. The ESS and PSQI scores and scores for environmental and somatic factors were significantly higher in workers with SWD than in those without this disorder. The ESS scores and scores for environmental and somatic factors were also associated with SWD in the logistic regression analyses. We suggest that susceptibility to SWD in the manufacturing industry may be associated with environmental and somatic factors related to falling asleep.

Night shift work exposure profile and obesity: Baseline results from a Chinese night shift worker cohort.

PubMed

Sun, Miaomiao; Feng, Wenting; Wang, Feng; Zhang, Liuzhuo; Wu, Zijun; Li, Zhimin; Zhang, Bo; He, Yonghua; Xie, Shaohua; Li, Mengjie; Fok, Joan P C; Tse, Gary; Wong, Martin C S; Tang, Jin-Ling; Wong, Samuel Y S; Vlaanderen, Jelle; Evans, Greg; Vermeulen, Roel; Tse, Lap Ah

2018-01-01

This study aimed to evaluate the associations between types of night shift work and different indices of obesity using the baseline information from a prospective cohort study of night shift workers in China. A total of 3,871 workers from five companies were recruited from the baseline survey. A structured self-administered questionnaire was employed to collect the participants' demographic information, lifetime working history, and lifestyle habits. Participants were grouped into rotating, permanent and irregular night shift work groups. Anthropometric parameters were assessed by healthcare professionals. Multiple logistic regression models were used to evaluate the associations between night shift work and different indices of obesity. Night shift workers had increased risk of overweight and obesity, and odds ratios (ORs) were 1.17 (95% CI, 0.97-1.41) and 1.27 (95% CI, 0.74-2.18), respectively. Abdominal obesity had a significant but marginal association with night shift work (OR = 1.20, 95% CI, 1.01-1.43). A positive gradient between the number of years of night shift work and overweight or abdominal obesity was observed. Permanent night shift work showed the highest odds of being overweight (OR = 3.94, 95% CI, 1.40-11.03) and having increased abdominal obesity (OR = 3.34, 95% CI, 1.19-9.37). Irregular night shift work was also significantly associated with overweight (OR = 1.56, 95% CI, 1.13-2.14), but its association with abdominal obesity was borderline (OR = 1.26, 95% CI, 0.94-1.69). By contrast, the association between rotating night shift work and these parameters was not significant. Permanent and irregular night shift work were more likely to be associated with overweight or abdominal obesity than rotating night shift work. These associations need to be verified in prospective cohort studies.

The direction of shift-work rotation impacts metabolic risk independent of chronotype and social jetlag--an exploratory pilot study.

PubMed

Kantermann, Thomas; Duboutay, Françoise; Haubruge, Damien; Hampton, Shelagh; Darling, Andrea L; Berry, Jacqueline L; Kerkhofs, Myriam; Boudjeltia, Karim Zouaoui; Skene, Debra J

2014-12-01

The aim of this pilot study was to explore the risk of metabolic abnormalities in steel workers employed in different shift-work rotations. Male workers in a steel factory [16 employed in a fast clockwise rotation (CW), 18 in slow counterclockwise rotation (CC), 9 day workers (DW); mean age 43.3 ± SD 6.8 years] with at least 5 years experience in their current work schedule participated. All workers provided fasting blood samples between 06:00 and 08:00 h for plasma glucose, insulin, apo-lipoproteins A and B (ApoA, ApoB), high- and low-density lipoproteins (HDL and LDL), total cholesterol (tCH), triglycerides (TG), minimally oxidized (mox) LDL, C-reactive protein (CRP), interleukin-8 (IL-8) and serum 25-hydroxyvitamin D (25(OH)D). HOMA index (homeostatic model assessment) was calculated to evaluate insulin resistance, beta cell function and risk of diabetes. Information on demographics, health, stimulants, sleep, social and work life, chronotype (phase of entrainment) and social jetlag (difference between mid-sleep on workdays and free days) as a surrogate for circadian disruption was collected by questionnaire. Neither chronotype nor social jetlag was associated with any of the metabolic risk blood markers. There were no significant differences in 25(OH)D, ApoA, ApoB, CRP, HDL, IL-8, insulin, LDL, mox-LDL, mox-LDL/ApoB ratio, tCH and TG levels between the three work groups. Although we did observe absolute differences in some of these markers, the small sample size of our study population might prevent these differences being statistically significant. Fasting glucose and HOMA index were significantly lower in CW compared to DW and CC, indicating lower metabolic risk. Reasons for the lower fasting glucose and HOMA index in CW workers remains to be clarified. Future studies of workers in different shift rotations are warranted to understand better the differential effects of shift-work on individual workers and their health indices.

Does the association of prostate cancer with night-shift work differ according to rotating vs. fixed schedule? A systematic review and meta-analysis.

PubMed

Mancio, Jennifer; Leal, Cátia; Ferreira, Marta; Norton, Pedro; Lunet, Nuno

2018-04-27

Recent studies suggested that the relation between night-shift work and prostate cancer may differ between rotating and fixed schedules. We aimed to quantify the independent association between night-shift work and prostate cancer, for rotating and fixed schedules. We searched MEDLINE for studies assessing the association of night-shift work, by rotating or fixed schedules, with prostate cancer. We computed summary relative risk (RR) estimates with 95% confidence intervals (95% CI) using the inverse variance method and quantified heterogeneity using the I 2 statistic. Meta-regression analysis was used to compare the summary RR estimates for rotating and fixed schedules, while reducing heterogeneity. A total of nine studies assessed the effect of rotating and, in addition, four of them provided the effect of fixed night-shift work, in relation to daytime workers. Rotating night-shift work was associated with a significantly increased risk of prostate cancer (RR = 1.06, 95% CI of 1.01 to 1.12; I 2  = 50%), but not fixed night-shift work (RR of 1.01, 95% CI of 0.81 to 1.26; I 2  = 33%). In meta-regression model including study design, type of population, and control of confounding, the summary RR was 20% higher for rotating vs. fixed schedule, with heterogeneity fully explained by these variables. This is the first meta-analysis suggesting that an increased risk of prostate cancer may be restricted to workers with rotating night shifts. However, the association was weak and additional studies are needed to further clarify this relation before it can be translated into measures for risk reduction in occupational settings.

Shift work schedule and night work load: Effects on body mass index - a four-year longitudinal study.

PubMed

Buchvold, Hogne Vikanes; Pallesen, Ståle; Waage, Siri; Bjorvatn, Bjørn

2018-05-01

Objectives The aim of this study was to investigate changes in body mass index (BMI) between different work schedules and different average number of yearly night shifts over a four-year follow-up period. Methods A prospective study of Norwegian nurses (N=2965) with different work schedules was conducted: day only, two-shift rotation (day and evening shifts), three-shift rotation (day, evening and night shifts), night only, those who changed towards night shifts, and those who changed away from schedules containing night shifts. Paired student's t-tests were used to evaluate within subgroup changes in BMI. Multiple linear regression analysis was used to evaluate between groups effects on BMI when adjusting for BMI at baseline, sex, age, marital status, children living at home, and years since graduation. The same regression model was used to evaluate the effect of average number of yearly night shifts on BMI change. Results We found that night workers [mean difference (MD) 1.30 (95% CI 0.70-1.90)], two shift workers [MD 0.48 (95% CI 0.20-0.75)], three shift workers [MD 0.46 (95% CI 0.30-0.62)], and those who changed work schedule away from [MD 0.57 (95% CI 0.17-0.84)] or towards night work [MD 0.63 (95% CI 0.20-1.05)] all had significant BMI gain (P<0.01) during the follow-up period. However, day workers had a non-significant BMI gain. Using adjusted multiple linear regressions, we found that night workers had significantly larger BMI gain compared to day workers [B=0.89 (95% CI 0.06-1.72), P<0.05]. We did not find any significant association between average number of yearly night shifts and BMI change using our multiple linear regression model. Conclusions After adjusting for possible confounders, we found that BMI increased significantly more among night workers compared to day workers.

Night shift work exposure profile and obesity: Baseline results from a Chinese night shift worker cohort

PubMed Central

Feng, Wenting; Wang, Feng; Zhang, Liuzhuo; Wu, Zijun; Li, Zhimin; Zhang, Bo; He, Yonghua; Xie, Shaohua; Li, Mengjie; Fok, Joan P. C.; Tse, Gary; Wong, Martin C. S.; Tang, Jin-ling; Wong, Samuel Y. S.; Vlaanderen, Jelle; Evans, Greg; Vermeulen, Roel; Tse, Lap Ah

2018-01-01

Aims This study aimed to evaluate the associations between types of night shift work and different indices of obesity using the baseline information from a prospective cohort study of night shift workers in China. Methods A total of 3,871 workers from five companies were recruited from the baseline survey. A structured self-administered questionnaire was employed to collect the participants’ demographic information, lifetime working history, and lifestyle habits. Participants were grouped into rotating, permanent and irregular night shift work groups. Anthropometric parameters were assessed by healthcare professionals. Multiple logistic regression models were used to evaluate the associations between night shift work and different indices of obesity. Results Night shift workers had increased risk of overweight and obesity, and odds ratios (ORs) were 1.17 (95% CI, 0.97–1.41) and 1.27 (95% CI, 0.74–2.18), respectively. Abdominal obesity had a significant but marginal association with night shift work (OR = 1.20, 95% CI, 1.01–1.43). A positive gradient between the number of years of night shift work and overweight or abdominal obesity was observed. Permanent night shift work showed the highest odds of being overweight (OR = 3.94, 95% CI, 1.40–11.03) and having increased abdominal obesity (OR = 3.34, 95% CI, 1.19–9.37). Irregular night shift work was also significantly associated with overweight (OR = 1.56, 95% CI, 1.13–2.14), but its association with abdominal obesity was borderline (OR = 1.26, 95% CI, 0.94–1.69). By contrast, the association between rotating night shift work and these parameters was not significant. Conclusion Permanent and irregular night shift work were more likely to be associated with overweight or abdominal obesity than rotating night shift work. These associations need to be verified in prospective cohort studies. PMID:29763461

Optimal Shift Duration and Sequence: Recommended Approach for Short-Term Emergency Response Activations for Public Health and Emergency Management

PubMed Central

Burgess, Paula A.

2007-01-01

Since September 11, 2001, and the consequent restructuring of the US preparedness and response activities, public health workers are increasingly called on to activate a temporary round-the-clock staffing schedule. These workers may have to make key decisions that could significantly impact the health and safety of the public. The unique physiological demands of rotational shift work and night shift work have the potential to negatively impact decisionmaking ability. A responsible, evidence-based approach to scheduling applies the principles of circadian physiology, as well as unique individual physiologies and preferences. Optimal scheduling would use a clockwise (morning-afternoon-night) rotational schedule: limiting night shifts to blocks of 3, limiting shift duration to 8 hours, and allowing 3 days of recuperation after night shifts. PMID:17413074

Shift Work, Chronotype, and Melatonin Patterns among Female Hospital Employees on Day and Night Shifts.

PubMed

Leung, Michael; Tranmer, Joan; Hung, Eleanor; Korsiak, Jill; Day, Andrew G; Aronson, Kristan J

2016-05-01

Shift work-related carcinogenesis is hypothesized to be mediated by melatonin; however, few studies have considered the potential effect modification of this underlying pathway by chronotype or specific aspects of shift work such as the number of consecutive nights in a rotation. In this study, we examined melatonin patterns in relation to shift status, stratified by chronotype and number of consecutive night shifts, and cumulative lifetime exposure to shift work. Melatonin patterns of 261 female personnel (147 fixed-day and 114 on rotations, including nights) at Kingston General Hospital were analyzed using cosinor analysis. Urine samples were collected from all voids over a 48-hour specimen collection period for measurement of 6-sulfatoxymelatonin concentrations using the Buhlmann ELISA Kit. Chronotypes were assessed using mid-sleep time (MSF) derived from the Munich Chronotype Questionnaire (MCTQ). Sociodemographic, health, and occupational information were collected by questionnaire. Rotational shift nurses working nights had a lower mesor and an earlier time of peak melatonin production compared to day-only workers. More pronounced differences in mesor and acrophase were seen among later chronotypes, and shift workers working ≥3 consecutive nights. Among nurses, cumulative shift work was associated with a reduction in mesor. These results suggest that evening-types and/or shift workers working ≥3 consecutive nights are more susceptible to adverse light-at-night effects, whereas long-term shift work may also chronically reduce melatonin levels. Cumulative and current exposure to shift work, including nights, affects level and timing of melatonin production, which may be related to carcinogenesis and cancer risk. Cancer Epidemiol Biomarkers Prev; 25(5); 830-8. ©2016 AACR. ©2016 American Association for Cancer Research.

[Working time and sleep in nursing staff employed in "3 x 8" and "2 x 12" fast rotating shift schedules].

PubMed

Castellini, G; Anelli, M M; Punzi, S; Boari, P; Camerino, D; Costa, G

2011-01-01

The study is aimed at assessing, in 200 nurses shift workers, the impact on sleep of two different working areas ("emergency" and "hospitalization") having the same "3 x 8" shift system, and of two different shift schedules at quick rotation ("2 x 12" and "3 x 8") in the same working area ("emergency"). Night and morning shifts prove to interfere to a greater extent with sleep in relation to both "2 x 12" and "3 x 8" shift systems as well as to the two operative areas. Hence the importance to consider in shift work planning, the direction of shift rotation and the length of the duty period according to the type of activity.

Health Effects of Shift Work

PubMed Central

LaDou, Joseph

1982-01-01

More than 13.5 million American workers, close to 20 percent of the work force, are assigned to evening or night shifts. In some industries such as automobile, petrochemical and textile manufacturing the proportion of shift workers is greater than 50 percent. As the popularity of shift work and other “alternative work schedules” grows, concern is increasing over the disturbance created in the lives of workers and their families by these economically and socially useful innovations. Twenty percent of workers are unable to tolerate shift work. Daily physiologic variations termed circadian rhythms are interactive and require a high degree of phase relationship to produce subjective feelings of wellbeing. Disturbance of these activities, circadian desynchronization, whether from passage over time zones or from shift rotation, results in health effects such as disturbance of the quantity and quality of sleep, disturbance of gastrointestinal and other organ system activities, and aggravation of diseases such as diabetes mellitus, epilepsy and thyrotoxicosis. Worker selection can reduce the number of health problems resulting from shift work. The periodic examination of shift workers is recommended. PMID:6962577

The impact of shift work and organizational work climate on health outcomes in nurses.

PubMed

von Treuer, Kathryn; Fuller-Tyszkiewicz, Matthew; Little, Glenn

2014-10-01

Shift workers have a higher rate of negative health outcomes than day shift workers. Few studies however, have examined the role of difference in workplace environment between shifts itself on such health measures. This study investigated variation in organizational climate across different types of shift work and health outcomes in nurses. Participants (n = 142) were nursing staff from a metropolitan Melbourne hospital. Demographic items elicited the type of shift worked, while the Work Environment Scale and the General Health Questionnaire measured organizational climate and health respectively. Analysis supported the hypotheses that different organizational climates occurred across different shifts, and that different organizational climate factors predicted poor health outcomes. Shift work alone was not found to predict health outcomes. Specifically, permanent night shift workers had significantly lower coworker cohesion scores compared with rotating day and evening shift workers and significantly higher managerial control scores compared with day shift workers. Further, coworker cohesion and involvement were found to be significant predictors of somatic problems. These findings suggest that differences in organizational climate between shifts accounts for the variation in health outcomes associated with shift work. Therefore, increased workplace cohesion and involvement, and decreased work pressure, may mitigate the negative health outcomes of shift workers. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Health-related interventions among night shift workers: a critical review of the literature.

PubMed

Neil-Sztramko, Sarah E; Pahwa, Manisha; Demers, Paul A; Gotay, Carolyn C

2014-11-01

Associations between shift work and chronic disease have been observed, but relatively little is known about how to mitigate these adverse health effects. This critical review aimed to (i) synthesize interventions that have been implemented among shift workers to reduce the chronic health effects of shift work and (ii) provide an overall evaluation of study quality. MeSH terms and keywords were created and used to conduct a rigorous search of MEDLINE, CINAHL, and EMBASE for studies published on or before 13 August 2012. Study quality was assessed using a checklist adapted from Downs & Black. Of the 5053 articles retrieved, 44 met the inclusion and exclusion criteria. Over 2354 male and female rotating and permanent night shift workers were included, mostly from the manufacturing, healthcare, and public safety industries. Studies were grouped into four intervention types: (i) shift schedule; (ii) controlled light exposure; (iii) behavioral; and, (iv) pharmacological. Results generally support the benefits of fast-forward rotating shifts; simultaneous use of timed bright light and light-blocking glasses; and physical activity, healthy diet, and health promotion. Mixed results were observed for hypnotics. Study quality varied and numerous deficiencies were identified. Except for hypnotics, several types of interventions reviewed had positive overall effects on chronic disease outcomes. There was substantial heterogeneity among studies with respect to study sample, interventions, and outcomes. There is a need for further high-quality, workplace-based prevention research conducted among shift workers.

Do permanent night workers show circadian adjustment? A review based on the endogenous melatonin rhythm.

PubMed

Folkard, Simon

2008-04-01

"Permanent" or "fixed" night shifts have been argued to offer a potential benefit over rotating shift systems in that they may serve to maximize circadian adjustment and hence minimize the various health and safety problems associated with night work. For this reason, some authors have argued in favor of permanent shift systems, but their arguments assume at least a substantial, if not complete, adjustment of the circadian clock. They have emphasized the finding that the day sleeps taken between successive night shifts by permanent night workers are rather longer than those of either slowly or rapidly rotating shift workers, but this could simply reflect increased pressure for sleep. The present paper reviews the literature on the adjustment to permanent night work of the circadian rhythm in the secretion of melatonin, which is generally considered to be the best known indicator of the state of the endogenous circadian body clock. Studies of workers in "abnormal" environments, such as oil rigs and remote mining operations, were excluded, as the nature of these unique settings might serve to assist adjustment. The results of the six studies included indicate that only a very small minority (<3%) of permanent night workers evidence "complete"adjustment of their endogenous melatonin rhythm to night work, less than one in four permanent night workers evidence sufficiently "substantial" adjustment to derive any benefit from it, there is no difference between studies conducted in normal or dim lighting, and there is no evidence of gender difference in the adjustment to permanent night work. It is concluded that in normal environments, permanent night-shift systems are unlikely to result in sufficient circadian adjustment in most individuals to benefit health and safety.

Educational and intervention strategies for improving a shift system: an experience in a disabled persons' facility.

PubMed

Sakai, K; Watanabe, A; Kogi, K

1993-01-01

The improvement of an irregular three-shift system with anti-clockwise rotation of workers of a disabled persons' facility covering 42 h a week was a subject for management-labour debate. Workers were complaining of physical fatigue, high prevalence of low back pain, sleep shortages associated with short inter-shift intervals, and irregular holidays. With the co-operation of trade union members, an educational and intervention programme was designed to analyse, plan, and implement improved shift rotation schemes. The programme consisted of (a) a group study on the existing system and effects on health and working life; (b) joint planning of potential schemes; (c) communication and feedback (d) testing and evaluation; and (e) agreement on an improved system. The group study was undertaken by means of time study, questionnaire and physiological methods, and the results were jointly discussed. This led to the planning of alternative shift schemes incorporating more regular, clockwise rotation. It was agreed to stage a trial period with a view to shorter working hours. This experience indicated the importance of a stepwise intervention strategy with frequent dialogues and a participatory process focusing on the broad range of working life and health issues.

Persistent rotating shift work exposure is a tough second hit contributing to abnormal liver function among on-site workers having sonographic fatty liver.

PubMed

Lin, Yu-Cheng; Chen, Pau-Chung

2015-03-01

To investigate the relationship between elevated serum alanine-transaminase (e-ALT) and persistent rotating shift work (p-RSW) among employees with sonographic fatty liver (SFL), the authors performed a retrospective analysis on a cohort of electronics manufacturing workers. The records of 758 workers (507 men, 251 women) with initially normal ALT and a mean age of 32.9 years were analyzed. A total of 109 workers (14.4%) developed e-ALT after 5 years. Compared with those having neither initial SFL nor p-RSW exposure, multivariate analysis indicated that employees who had initial SFL but without p-RSW finally had a higher risk (odds ratio = 2.9; 95% confidence interval [CI] = 1.7-5.1) for developing e-ALT; workers with baseline SFL plus p-RSW had a 3.7-fold increased risk (95% CI = 1.8-7.5). SFL poses a conspicuous risk for the development of e-ALT, and persistent p-RSW exposure significantly aggravates the development of e-ALT among on-site workers with preexisting SFL. © 2012 APJPH.

Examining Exposure Assessment in Shift Work Research: A Study on Depression Among Nurses.

PubMed

Hall, Amy L; Franche, Renée-Louise; Koehoorn, Mieke

2018-02-13

Coarse exposure assessment and assignment is a common issue facing epidemiological studies of shift work. Such measures ignore a number of exposure characteristics that may impact on health, increasing the likelihood of biased effect estimates and masked exposure-response relationships. To demonstrate the impacts of exposure assessment precision in shift work research, this study investigated relationships between work schedule and depression in a large survey of Canadian nurses. The Canadian 2005 National Survey of the Work and Health of Nurses provided the analytic sample (n = 11450). Relationships between work schedule and depression were assessed using logistic regression models with high, moderate, and low-precision exposure groupings. The high-precision grouping described shift timing and rotation frequency, the moderate-precision grouping described shift timing, and the low-precision grouping described the presence/absence of shift work. Final model estimates were adjusted for the potential confounding effects of demographic and work variables, and bootstrap weights were used to generate sampling variances that accounted for the survey sample design. The high-precision exposure grouping model showed the strongest relationships between work schedule and depression, with increased odds ratios [ORs] for rapidly rotating (OR = 1.51, 95% confidence interval [CI] = 0.91-2.51) and undefined rotating (OR = 1.67, 95% CI = 0.92-3.02) shift workers, and a decreased OR for depression in slow rotating (OR = 0.79, 95% CI = 0.57-1.08) shift workers. For the low- and moderate-precision exposure grouping models, weak relationships were observed for all work schedule categories (OR range 0.95 to 0.99). Findings from this study support the need to consider and collect the data required for precise and conceptually driven exposure assessment and assignment in future studies of shift work and health. Further research into the effects of shift rotation frequency on depression is also recommended. © The Author(s) 2018. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Contributors to shift work tolerance in South Korean nurses working rotating shift.

PubMed

Jung, Hye-Sun; Lee, Bokim

2015-05-01

Shift workers have rapidly increased in South Korea; however, there is no published research exploring shift work tolerance among South Korean workers. This study aimed to investigate factors related to shift work tolerance in South Korean nurses. The sample comprised of 660 nurses who worked shifts in a large hospital in South Korea. A structured questionnaire included following comprehensive variables: demographic (age and number of children), individual (morningness and self-esteem), psychosocial (social support and job stress), lifestyle (alcohol consumption, physical activity, and BMI), and working condition factors (number of night shifts and working hours). Shift work tolerance was measured in terms of insomnia, fatigue, and depression. The results of hierarchical regressions indicate that all variables, except for three, number of children, BMI, and working hours, were related to at least one of the symptoms associated with shift work tolerance. Based on these results, we offer some practical implications to help improve shift work tolerance of workers. Copyright © 2014 Elsevier Inc. All rights reserved.

Expert system application for prioritizing preventive actions for shift work: shift expert.

PubMed

Esen, Hatice; Hatipoğlu, Tuğçen; Cihan, Ahmet; Fiğlali, Nilgün

2017-09-19

Shift patterns, work hours, work arrangements and worker motivations have increasingly become key factors for job performance. The main objective of this article is to design an expert system that identifies the negative effects of shift work and prioritizes mitigation efforts according to their importance in preventing these negative effects. The proposed expert system will be referred to as the shift expert. A thorough literature review is conducted to determine the effects of shift work on workers. Our work indicates that shift work is linked to demographic variables, sleepiness and fatigue, health and well-being, and social and domestic conditions. These parameters constitute the sections of a questionnaire designed to focus on 26 important issues related to shift work. The shift expert is then constructed to provide prevention advice at the individual and organizational levels, and it prioritizes this advice using a fuzzy analytic hierarchy process model, which considers comparison matrices provided by users during the prioritization process. An empirical study of 61 workers working on three rotating shifts is performed. After administering the questionnaires, the collected data are analyzed statistically, and then the shift expert produces individual and organizational recommendations for these workers.

Night shift work and lung cancer risk among female textile workers in Shanghai, China.

PubMed

Kwon, Paul; Lundin, Jessica; Li, Wenjin; Ray, Roberta; Littell, Christopher; Gao, Daoli; Thomas, David B; Checkoway, Harvey

2015-01-01

In 2007, the International Agency for Research on Cancer classified shift work that involves circadian disruption as a probable human carcinogen. Suppression of the anti-neoplastic hormone, melatonin, is a presumed mechanism of action. We conducted a case-cohort study nested within a cohort of 267,400 female textile workers in Shanghai, China. Newly diagnosed lung cancer cases (n = 1451) identified during the study period (1989-2006) were compared with an age-stratified subcohort (n = 3040). Adjusting for age, smoking, parity, and endotoxin exposure, relative risks [hazard ratios (HRs)] were estimated by Cox regression modeling to assess associations with cumulative years and nights of rotating shift work. Results did not consistently reveal any increased risk of lung cancer among rotating shift work or statistically significant trends for both cumulative years (HR 0.82, 95% CI 0.66 to 1.02; P(trend) = 0.294) and nights (HR 0.81, 95% CI 0.65 to 1.00; P(trend) = 0.415). Further analyses imposing 10- and 20-year lag times for disease latency also revealed similar results. Contrary to the initial hypothesis, rotating nighttime shift work appears to be associated with a relatively reduced lung cancer risk although the magnitude of the effect was modest and not statistically significant.

Factors associated with shift work disorder in nurses working with rapid-rotation schedules in Japan: the nurses' sleep health project.

PubMed

Asaoka, Shoichi; Aritake, Sayaka; Komada, Yoko; Ozaki, Akiko; Odagiri, Yuko; Inoue, Shigeru; Shimomitsu, Teruichi; Inoue, Yuichi

2013-05-01

Workers who meet the criteria for shift work disorder (SWD) have elevated levels of risk for various health and behavioral problems. However, the impact of having SWD on shiftworkers engaged in rapid-rotation schedules is unknown. Moreover, the risk factors for the occurrence of SWD remain unclear. To clarify these issues, we conducted a questionnaire-based, cross-sectional survey on a sample of shiftworking nurses. Responses were obtained from 1202 nurses working at university hospitals in Tokyo, Japan, including 727 two-shift workers and 315 three-shift workers. The questionnaire included items relevant to age, gender, family structure, work environment, health-related quality of life (QOL), diurnal type, depressive symptoms, and SWD. Participants who reported insomnia and/or excessive sleepiness for at least 1 mo that was subjectively relevant to their shiftwork schedules were categorized as having SWD. The prevalence of SWD in the sampled shiftworking nurses was 24.4%; shiftworking nurses with SWD showed lower health-related QOL and more severe depressive symptoms, with greater rates of both actual accidents/errors and near misses, than those without SWD. The results of logistic regression analyses showed that more time spent working at night, frequent missing of nap opportunities during night work, and having an eveningness-oriented chronotype were significantly associated with SWD. The present study indicated that SWD might be associated with reduced health-related QOL and decreased work performance in shiftworking nurses on rapid-rotation schedules. The results also suggested that missing napping opportunities during night work, long nighttime working hours, and the delay of circadian rhythms are associated with the occurrence of SWD among shiftworking nurses on rapid-rotation schedules.

Aging and shiftwork: the effects of 20 years of rotating 12-hour shifts among petroleum refinery operators.

PubMed

Bourdouxhe, M A; Quéinnec, Y; Granger, D; Baril, R H; Guertin, S C; Massicotte, P R; Levy, M; Lemay, F L

1999-01-01

The survey was conducted in a Canadian refinery where operators have been working rotating 12-hour shifts for 20 years. A multidisciplinary approach was adopted, based on 12 sources of data. Descriptive statistics and chronoergonomic observations were used. The most marked consequences of the schedule were observed among former shiftworkers. Among current shift workers, sleep deficit, chronic fatigue, health problems, and disruption of social and family life were the most serious effects observed. Aging and under-staffing, however, interact with schedule by necessitating overtime and reducing the actual number of rest days, which in turn affects fatigue and reliability. In the near future, the low replacement rate of the workforce and the limitations on reassignment of aging workers to day shifts will probably prevent the selection process from playing its "protective" role. Besides, with the 5-year delay of the retirement age, the harmful effects in older operators active over the next 5-10 years may prove greater than those observed in this study.

Sleep Duration and Chronic Fatigue Are Differently Associated with the Dietary Profile of Shift Workers

PubMed Central

Heath, Georgina; Coates, Alison; Sargent, Charli; Dorrian, Jillian

2016-01-01

Shift work has been associated with dietary changes. This study examined factors associated with the dietary profiles of shift workers from several industries (n = 118, 57 male; age = 43.4 ± 9.9 years) employed on permanent mornings, nights, or rotating 8-h or 12-h shifts. The dietary profile was assessed using a Food Frequency Questionnaire. Shift-related (e.g., sleep duration and fatigue), work-related (e.g., industry), and demographic factors (e.g., BMI) were measured using a modified version of the Standard Shift work Index. Mean daily energy intake was 8628 ± 3161 kJ. As a percentage of daily energy intake, all workers reported lower than recommended levels of carbohydrate (CHO, 45%–65%). Protein was within recommended levels (15%–25%). Permanent night workers were the only group to report higher than recommended fat intake (20%–35%). However, all workers reported higher than recommended levels of saturated fat (>10%) with those on permanent nights reporting significantly higher levels than other groups (Mean = 15.5% ± 3.1%, p < 0.05). Shorter sleep durations and decreased fatigue were associated with higher CHO intake (p ≤ 0.05) whereas increased fatigue and longer sleep durations were associated with higher intake of fat (p ≤ 0.05). Findings demonstrate sleep duration, fatigue, and shift schedule are associated with the dietary profile of shift workers. PMID:27916861

Sleep Duration and Chronic Fatigue Are Differently Associated with the Dietary Profile of Shift Workers.

PubMed

Heath, Georgina; Coates, Alison; Sargent, Charli; Dorrian, Jillian

2016-11-30

Shift work has been associated with dietary changes. This study examined factors associated with the dietary profiles of shift workers from several industries ( n = 118, 57 male; age = 43.4 ± 9.9 years) employed on permanent mornings, nights, or rotating 8-h or 12-h shifts. The dietary profile was assessed using a Food Frequency Questionnaire. Shift-related (e.g., sleep duration and fatigue), work-related (e.g., industry), and demographic factors (e.g., BMI) were measured using a modified version of the Standard Shift work Index. Mean daily energy intake was 8628 ± 3161 kJ. As a percentage of daily energy intake, all workers reported lower than recommended levels of carbohydrate (CHO, 45%-65%). Protein was within recommended levels (15%-25%). Permanent night workers were the only group to report higher than recommended fat intake (20%-35%). However, all workers reported higher than recommended levels of saturated fat (>10%) with those on permanent nights reporting significantly higher levels than other groups (Mean = 15.5% ± 3.1%, p < 0.05). Shorter sleep durations and decreased fatigue were associated with higher CHO intake ( p ≤ 0.05) whereas increased fatigue and longer sleep durations were associated with higher intake of fat ( p ≤ 0.05). Findings demonstrate sleep duration, fatigue, and shift schedule are associated with the dietary profile of shift workers.

Work and Nonwork Experiences of Employees on Fixed and Rotating Shifts: An Empirical Assessment.

ERIC Educational Resources Information Center

Jamal, Muhammad; Jamal, Saleha M.

1982-01-01

Investigated the relationship between shift time and use of leisure time, nonwork satisfaction, and mental and physical health among rank-and-file workers and nurses. Found employees working on fixed shift had higher job performance, motivation, and patients' care skill, and probably enjoyed better physical and emotional health. (Author/JAC)

[The productivity of female shift workers].

PubMed

Vidacek, S; Radosević-Vidacek, B; Kaliterna, L; Prizmić, Z

1990-12-01

The productivity of female shift workers, working on a weekly rotating three-shift system, was examined. The afternoon shift was found to be the most productive and the night shift the least productive one. The greatest difference in productivity between shifts was found in the first two days of the week, when the productivity on night shift was significantly lower than that on the other two shifts. From the third day on there were no longer significant differences in productivity between shifts. The most productive and the least productive workers on night shift did not significantly differ in extraversion or in sleep duration after the night shift. Family responsibility was found to be associated with the duration of sleep after the night shift: married women slept significantly shorter after the night shift than unmarried women. However, this difference in sleep duration was not associated with productivity on night shift. Sleep duration after the afternoon shift (8 hours 40 minutes) was on average two hours longer than after the other two shifts. The difference in sleep duration after different shifts, along with circadian variations in alertness, readiness for work and performance efficiency, could be responsible for differences in productivity between shifts.

Shifting schedules: the health effects of reorganizing shift work.

PubMed

Bambra, Clare L; Whitehead, Margaret M; Sowden, Amanda J; Akers, Joanne; Petticrew, Mark P

2008-05-01

Approximately one fifth of workers are engaged in some kind of shift work. The harmful effects of shift work on the health and work-life balance of employees are well known. A range of organizational interventions has been suggested to address these negative effects. This study undertook the systematic review (following Quality Of Reporting Of Meta [QUORUM] analyses guidelines) of experimental and quasi-experimental studies, from any country (in any language) that evaluated the effects on health and work-life balance of organizational-level interventions that redesign shift work schedules. Twenty-seven electronic databases (medical, social science, economic) were searched. Data extraction and quality appraisal were carried out by two independent reviewers. Narrative synthesis was performed. The review was conducted between October 2005 and November 2006. Twenty-six studies were found relating to a variety of organizational interventions. No one type of intervention was found to be consistently harmful to workers. However, three types were found to have beneficial effects on health and work-life balance: (1) switching from slow to fast rotation, (2) changing from backward to forward rotation, and (3) self-scheduling of shifts. Improvements were usually at little or no direct organizational cost. However, there were concerns about the generalizability of the evidence, and no studies reported on impacts on health inequalities. This review reinforces the findings of epidemiologic and laboratory-based research by suggesting that certain organizational-level interventions can improve the health of shift workers, their work-life balance, or both. This evidence could be useful when designing interventions to improve the experience of shift work.

Shift work and health--a critical review of the literature on working hours.

PubMed

Harrington, J M

1994-09-01

Working outside normal hours either by extended days or shift work is a fact of industrial society. Its economic advantages must be weighed against detrimental effects on the individual worker in the form of circadian rhythm disturbance, poorer quality and quantity of sleep and increased fatigue. The link between shift work and increased cardiovascular morbidity and mortality has strengthened in recent years. The case for an association with gastrointestinal disease remains quite good. Evidence of poorer work performance and increased accidents, particularly on the night shift, is persuasive, although individual factors may be as important as workplace factors. Correct shift work scheduling is important and for rotating shifts, rapid forward rotation is the least disruptive option. The compressed working week of 10 to 12-hour shifts is gaining popularity but evidence is too scant at present to suggest there are many long-term health and safety risks provided the rest day block is preserved. Optimal hours for the working week cannot be formulated on present scientific evidence, though working more than 48-56 hours a week probably carries serious health and safety implications. The inherent conflict between the interest of the worker and the enterprise over unsocial hours can be mitigated by improvements in working conditions especially at night and by advice to the worker on coping strategies. Further research is needed on the effects of the compressed working week, as well as the influence of culture, task and gender on any health effects. Studies to define individual characteristics which may cause shift work intolerance would be of great practical use.

Association between shift work and the risk of death from biliary tract cancer in Japanese men.

PubMed

Lin, Yingsong; Nishiyama, Takeshi; Kurosawa, Michiko; Tamakoshi, Akiko; Kubo, Tatsuhiko; Fujino, Yoshihisa; Kikuchi, Shogo

2015-10-21

There is increasing evidence suggesting that shift work involving night work may increase cancer risk. We examined the association between working rotating shifts and the risk of death from biliary tract cancer among Japanese men who participated in the Japan Collaborative Cohort Study. Of the 46,395 men recruited, 22,224 men aged 40-65 at baseline (1988-1990) who reported working full-time or were self-employed were included in the present analysis. The study subjects were followed through December 31, 2009. Information regarding occupation and lifestyle factors was collected using a self-administered questionnaire. Cox proportional hazard models were used to estimate the hazard ratio (HR) and 95 % confidence interval (CI) for the risk of death from biliary tract cancer in relation to shift work. During a mean 17-year follow-up, we observed 94 biliary tract cancer deaths, including 23 deaths from gallbladder cancer and 71 deaths from extrahepatic bile duct cancer. Overall, shift work was associated with a statistically non-significant increase in the risk of biliary tract cancer, with an HR of 1.50 (95 % CI: 0.81-2.77), among rotating shift workers. When the analysis was limited to extrahepatic bile duct cancer, a significant association appeared, with a multivariable-adjusted HR of 1.93 (95 % CI: 1.00-3.72) for rotating shift workers. Our data indicate that shift work may be associated with increased risk of death from extrahepatic bile duct cancer in this cohort of Japanese men. The association with gallbladder cancer remains unclear because of the small number of deaths.

Investigating Cortisol Production and Pattern as Mediators in the Relationship Between Shift Work and Cardiometabolic Risk.

PubMed

Ritonja, Jennifer; Aronson, Kristan J; Day, Andrew G; Korsiak, Jill; Tranmer, Joan

2018-05-01

Shift work is a risk factor for many diseases, including cardiovascular disease. Although the biological pathways are still unclear, it is hypothesized that cortisol disruption during night work is an intermediate. The objective of this study is to determine whether total cortisol production and cortisol pattern mediate the relationship between current shift work and cardiometabolic risk (CMR) among female hospital employees. A cross-sectional study was conducted among 326 female employees (166 rotating shift workers, 160 day workers), recruited from a hospital in Southeastern Ontario, Canada, during 2011 to 2014. Participants completed a baseline interview, questionnaire, and clinical exam. Urine samples were collected over two 24-hour periods and used to analyze creatinine-adjusted cortisol, which was then used to calculate total cortisol production (AUC G ), and pattern (AUC I ). Mediation analysis was performed to test the mediating effect of cortisol in the relationship between shift work and a continuous CMR score. Current shift work is associated with a 0.52 higher CMR score (95% CI: 0.15, 0.89), a lower cortisol output (AUC G ), and a flatter pattern (AUC I ) over a 2-day period. AUC G is a partial mediator in the relationship between shift work and CMR, whereas AUC I is not. AUC G is also associated with CMR while controlling for shift work, suggesting that lower total cortisol production is also linked to CMR in non-shift workers. Total cortisol production is a partial mediator in the relationship between rotating shift work and CMR among female hospital employees, whereas cortisol pattern is not a mediator. Copyright © 2018 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Impaired driving performance in shiftworkers: the role of the circadian system in a multifactorial model

NASA Technical Reports Server (NTRS)

Richardson, G. S.; Miner, J. D.; Czeisler, C. A.

1989-01-01

A substantial and growing percentage of the U.S. work force now works on a rotating shift schedule. The repeated changes in sleep-wake, meal and work times inherent in such schedules conflict with the dictates of the internal biological clock and have adverse consequences for the health of the shiftworker population. An important consequence of this conflict is impaired performance, both on and off the job, as indexed by the increased incidence of motor vehicle accidents in shift workers. In this paper we report the results of a survey administered to rotating shift and straight day workers at a manufacturing plant in the eastern U.S. This survey documents an increased incidence of motor vehicle accidents or "near misses" in which sleepiness was implicated as a cause by the respondent. Complaints of poor sleep and increased sleepiness were also significantly more common in shiftworkers than day workers. Last, shiftworkers reported higher caffeine and alcohol consumption, and were more likely to use alcohol as a sleep aid. Although causal links cannot be established using these associative observations alone, previously reported experience with alteration of shift schedules, improvement of levels of alertness, and reduction in adverse performance outcomes corroborate the possibility of a causal link and suggest potential interventions.

Rotating night shift work and physical activity of nurses and midwives in the cross-sectional study in Łódź, Poland.

PubMed

Peplonska, Beata; Bukowska, Agnieszka; Sobala, Wojciech

2014-12-01

Shift work have been thought to restrict participation in leisure time activities, but the knowledge about physical activity in rotating night shift nurses has been limited so far. We investigated the associations between the rotating night shift work and physical activity using data from a cross-sectional study among nurses and midwives. This study included 354 nurses and midwives (aged 40-60) currently working rotating night shifts and 371 ones working days only. The information on the work characteristics and potential covariates was collected via a personal interview. Weight and height were measured and BMI was calculated. Physical activity was assessed according to the international questionnaire on physical activity - IPAQ, and four domains: leisure time, occupational, transport related and household were analyzed. Women who reported none leisure time activity were defined as recreationally "inactive". The associations were examined with multiple linear or logistic regression models adjusted for age, season of the year, number of full term births, marital status and BMI. Total and occupational physical activity was significantly higher among nurses working rotating night shifts. However, leisure time activity was significantly affected among rotating night shift nurses and midwives, compared to women working during the days only, with increased odds ratio for recreational "inactivity" (OR = 1.57, 95% CI: 1.11-2.20). Rotating night shift work among nurses and midwives is associated with higher occupational physical activity but lower leisure time activity. Initiatives supporting exercising among night shift workers are recommended.

Glucose metabolism during rotational shift-work in healthcare workers.

PubMed

Sharma, Anu; Laurenti, Marcello C; Dalla Man, Chiara; Varghese, Ron T; Cobelli, Claudio; Rizza, Robert A; Matveyenko, Aleksey; Vella, Adrian

2017-08-01

Shift-work is associated with circadian rhythm disruption and an increased risk of obesity and type 2 diabetes. We sought to determine the effect of rotational shift-work on glucose metabolism in humans. We studied 12 otherwise healthy nurses performing rotational shift-work using a randomised crossover study design. On each occasion, participants underwent an isotope-labelled mixed meal test during a simulated day shift and a simulated night shift, enabling simultaneous measurement of glucose flux and beta cell function using the oral minimal model. We sought to determine differences in fasting and postprandial glucose metabolism during the day shift vs the night shift. Postprandial glycaemic excursion was higher during the night shift (381±33 vs 580±48 mmol/l per 5 h, p<0.01). The time to peak insulin and C-peptide and nadir glucagon suppression in response to meal ingestion was also delayed during the night shift. While insulin action did not differ between study days, the beta cell responsivity to glucose (59±5 vs 44±4 × 10 -9  min -1 ; p<0.001) and disposition index were decreased during the night shift. Impaired beta cell function during the night shift may result from normal circadian variation, the effect of rotational shift-work or a combination of both. As a consequence, higher postprandial glucose concentrations are observed during the night shift.

Change from an 8-hour shift to a 12-hour shift, attitudes, sleep, sleepiness and performance.

PubMed

Lowden, A; Kecklund, G; Axelsson, J; Akerstedt, T

1998-01-01

The present study sought to evaluate the effect of a change from a rotating 3-shift (8-hour) to a 2-shift shift (12 hour) schedule on sleep, sleepiness, performance, perceived health, and well-being. Thirty-two shift workers at a chemical plant (control room operators) responded to a questionnaire a few months before a change was made in their shift schedule and 10 months after the change. Fourteen workers also filled out a diary, carried activity loggers, and carried out reaction-time tests (beginning and end of shift). Fourteen day workers served as a reference group for the questionnaires and 9 were intensively studied during a week with workdays and a free weekend. The questionnaire data showed that the shift change increased satisfaction with workhours, sleep, and time for social activities. Health, perceived accident risk, and reaction-time performance were not negatively affected. Alertness improved and subjective recovery time after night work decreased. The quick changes in the 8-hour schedule greatly increased sleep problems and fatigue. Sleepiness integrated across the entire shift cycle showed that the shift workers were less alert than the day workers, across workdays and days off (although alertness increased with the 12-hour shift). The change from 8-hour to 12-hour shifts was positive in most respects, possibly due to the shorter sequences of the workdays, the longer sequences of consecutive days off, the fewer types of shifts (easier planning), and the elimination of quick changes. The results may differ in groups with a higher work load.

Effect of rotating shift work on childbearing and birth weight: a study of women working in a semiconductor manufacturing factory.

PubMed

Lin, Yu-Cheng; Chen, Mei-Huei; Hsieh, Chia-Jung; Chen, Pau-Chung

2011-05-01

Stable circadian rhythm is important for both maternal and fetal health. This retrospective analysis of women in a semiconductor factory evaluated the effect of shift work exposure on childbearing and birth weight. Records of 440 female employees (initial mean age: 28.4 years) including 111 mothers who had 158 live births during the period of observation (1997-2007) were reviewed. The data analyzed included maternal age, general health condition, highest educational level, life-style and occupational factors, as well as newborn gender, birth weight, birth order and gestational age. The childbearing rates of female workers on three different work schedules (consistent daytime work (CDW), intermittent (i-) or persistent (p-) rotating shift works (RSW)) were 32.1%, 20.0% and 25.4%, respectively (P=0.047). After controlling for potential confounding factors, childbearing rates among women with CDW exceeded those of shift workers (odds ratio (OR), 1.7; 95% confidence interval (CI), 1.0-3.0). The birth weights of newborns from mothers on the three work schedules (CDW, i-RSW and p-RSW) were significantly different (3271.7±395.4, 3251.3±460.9, and 2998.5±381.2 g, respectively (P<0.01). Newborns within the lightest birth weight quintile were significantly more likely to be born to mothers with exposure to p-RSW (OR, 4.3; 95% CI, 1.1-16.8). Rotating shift work exposure was significantly associated with decreased childbearing and lighter birth weight in women working in this semiconductor manufacturing factory. Work schedules should be carefully planned for female employees who are pregnant or preparing for pregnancy. Prenatal evaluations for mothers with persistent day-night rotating shift work exposures are especially necessary.

Prevention of fatigue and insomnia in shift workers-a review of non-pharmacological measures.

PubMed

Richter, Kneginja; Acker, Jens; Adam, Sophia; Niklewski, Guenter

2016-01-01

Excessive fatigue and insomnia are common among shift workers and can lead to negative effects such as reduced work performance, processing errors, accidents at work, absenteeism, reduced quality of life, and symptoms of depression. Moreover, work in rotating shifts can be a risk factor for different somatic and psychiatric diseases and may contribute to poor health, especially in elder adults and women. This review aims to show non-pharmacological preventive measures against fatigue and insomnia in shift workers. Computerized literature searches in MedLine and in the Cochrane Library were performed with the following key words: shift work disorder, fatigue, insomnia, shift work, measures, treatment, therapy, strategies and coping. The search was limited to non-pharmacological studies that were conducted on human subjects and published as English-language articles in peer-reviewed journals since 1970. Additional studies were identified through the reference sections of relevant articles. Eighteen articles on fatigue in shift workers, including six original research articles with a total sample size of 3504 probands consisting of industrial workers, office employees, aircraft maintenance engineers, and non-shift workers working in simulated shifts, were analyzed, as well as seven articles on insomnia, including an original research article with a sample size of 26 media workers. Also, 4 reviews on shift work disorder were analyzed. The occurrence of fatigue and insomnia in shift workers associated with a working period is described as shift work disorder. Estimations on the prevalence of shift work disorder in shift workers vary between 5 % and about 20 %; about one in three shift workers is affected by insomnia and up to 90 % of shift workers report regular fatigue and sleepiness at the workplace. We concluded that there is a necessity for treatments to improve the sleep quality of the shift working population. The most common non-pharmacological recommendations to improve sleep quality and to reduce insomnia and fatigue were scheduling, bright light exposure, napping, psychoeducation for sleep hygiene, and cognitive-behavioral measures. Some important preventive coping strategies for fatigue associated with shift work such as napping and exposure to bright light have already been investigated and are generally approved. A few studies also provide good evidence for the efficacy of cognitive-behavioral techniques in the treatment of chronic primary and comorbid insomnia. These coping strategies summarized in this paper should be considered in the workplace health promotion programs of each work environment to improve working conditions for shift workers and to save money.

[Shiftwork and health--experience from a chemical company].

PubMed

Oberlinner, C; Lang, S; Nasterlack, M; Yong, M

2013-03-01

Shiftwork is an essential part of our society. At the same time scientific evaluations demonstrate possible negative effects of shiftwork on the health status of the employees. Against this background we performed different studies to evaluate these effects within the specific shift system in a large chemical site in Germany. METHODS AND STUDY GROUP: To evaluate the impact of the different working times on job-related stress perception and work-life-balance we performed a cross-sectional study with 1494 blue collar workers (825 shift- and 669 day workers). Employees working in the rotating shift system reported lower frequencies of perceived time pressure (p = 0.008), and lower stress levels (p = 0.01), compared to the day workers. No significant difference was found with regard to work-life-balance and other aspects of job-related stress perception within both groups. Against the general opinion and study-results in the past we did not find a negative effect of our shift-system on self-reported stress. These results are in accordance with results of other cohort-studies on the specific shift system within the company demonstrating no difference in the health status of our shift workers compared to day workers. © Georg Thieme Verlag KG Stuttgart · New York.

Physical Activity, Energy Expenditure, Nutritional Habits, Quality of Sleep and Stress Levels in Shift-Working Health Care Personnel.

PubMed

Roskoden, Frederick Charles; Krüger, Janine; Vogt, Lena Johanna; Gärtner, Simone; Hannich, Hans Joachim; Steveling, Antje; Lerch, Markus M; Aghdassi, Ali A

2017-01-01

Among health care personnel working regular hours or rotating shifts can affect parameters of general health and nutrition. We have investigated physical activity, sleep quality, metabolic activity and stress levels in health care workers from both groups. We prospectively recruited 46 volunteer participants from the workforce of a University Medical Department of which 23 worked in rotating shifts (all nursing) and 21 non-shift regular hours (10 nursing, 13 clerical staff). All were investigated over 7 days by multisensory accelerometer (SenseWear Bodymedia® armband) and kept a detailed food diary. Physical activity and resting energy expenditure (REE) were measured in metabolic equivalents of task (METs). Quality of sleep was assessed as Pittsburgh Sleeping Quality Index and stress load using the Trier Inventory for Chronic Stress questionnaire (TICS). No significant differences were found for overall physical activity, steps per minute, time of exceeding the 3 METs level or sleep quality. A significant difference for physical activity during working hours was found between shift-workers vs. non-shift-workers (p<0.01) and for shift-working nurses (median = 2.1 METs SE = 0.1) vs. non-shift-working clerical personnel (median = 1.5 METs SE = 0.07, p<0.05). Non-shift-working nurses had a significantly lower REE than the other groups (p<0.05). The proportion of fat in the diet was significantly higher (p<0.05) in the office worker group (median = 42% SE = 1.2) whereas shift-working nurses consumed significantly more carbohydrates (median = 46% SE = 1.4) than clerical staff (median = 41% SE = 1.7). Stress assessment by TICS confirmed a significantly higher level of social overload in the shift working group (p<0.05). In this prospective cohort study shift-working had no influence on overall physical activity. Lower physical activity during working hours appears to be compensated for during off-hours. Differences in nutritional habits and stress load warrant larger scale trials to determine the effect on implicit health-associated conditions.

Physical Activity, Energy Expenditure, Nutritional Habits, Quality of Sleep and Stress Levels in Shift-Working Health Care Personnel

PubMed Central

Vogt, Lena Johanna; Gärtner, Simone; Hannich, Hans Joachim; Steveling, Antje; Lerch, Markus M.

2017-01-01

Background Among health care personnel working regular hours or rotating shifts can affect parameters of general health and nutrition. We have investigated physical activity, sleep quality, metabolic activity and stress levels in health care workers from both groups. Methods We prospectively recruited 46 volunteer participants from the workforce of a University Medical Department of which 23 worked in rotating shifts (all nursing) and 21 non-shift regular hours (10 nursing, 13 clerical staff). All were investigated over 7 days by multisensory accelerometer (SenseWear Bodymedia® armband) and kept a detailed food diary. Physical activity and resting energy expenditure (REE) were measured in metabolic equivalents of task (METs). Quality of sleep was assessed as Pittsburgh Sleeping Quality Index and stress load using the Trier Inventory for Chronic Stress questionnaire (TICS). Results No significant differences were found for overall physical activity, steps per minute, time of exceeding the 3 METs level or sleep quality. A significant difference for physical activity during working hours was found between shift-workers vs. non-shift-workers (p<0.01) and for shift-working nurses (median = 2.1 METs SE = 0.1) vs. non-shift-working clerical personnel (median = 1.5 METs SE = 0.07, p<0.05). Non-shift-working nurses had a significantly lower REE than the other groups (p<0.05). The proportion of fat in the diet was significantly higher (p<0.05) in the office worker group (median = 42% SE = 1.2) whereas shift-working nurses consumed significantly more carbohydrates (median = 46% SE = 1.4) than clerical staff (median = 41% SE = 1.7). Stress assessment by TICS confirmed a significantly higher level of social overload in the shift working group (p<0.05). Conclusion In this prospective cohort study shift-working had no influence on overall physical activity. Lower physical activity during working hours appears to be compensated for during off-hours. Differences in nutritional habits and stress load warrant larger scale trials to determine the effect on implicit health-associated conditions. PMID:28081231

The effect of shift rotation on employee cortisol profile, sleep quality, fatigue, and attention level: a systematic review.

PubMed

Niu, Shu-Fen; Chung, Min-Huey; Chen, Chiung-Hua; Hegney, Desley; O'Brien, Anthony; Chou, Kuei-Ru

2011-03-01

Disrupted circadian rhythm, especially working night duty together with irregular sleep patterns, sleep deprivation, and fatigue, creates an occupational health risk associated with diminished vigilance and work performance. This study reviewed the effect of shift rotations on employee cortisol profile, sleep quality, fatigue, and attention level. Researchers conducted a systematic review of relevant articles published between 1996 and 2008 that were listed on the following databases: SCOPUS, OVID, Blackwell Science, EBSCO Host, PsycINFO, Cochrane Controlled Trials Register, and CEPS. A total of 28 articles were included in the review. Previous research into the effects of shift work on cortisol profiles, sleep quality, fatigue, and attention used data assessed at evidence Levels II to IV. Our systematic review confirmed a conflict between sleep-wake cycle and light-dark cycle in night work. Consequences of circadian rhythm disturbance include disruption of sleep, decreased vigilance, general feeling of malaise, and decreased mental efficiency. Shift workers who sleep during the day (day sleepers) experience cortisol secretion increases, which diminish the healing power of sleep and enjoy 1 to 4 hours less sleep on average than night sleepers. Sleep debt accumulation results in chronic fatigue. Prolonged fatigue and inadequate recovery result in decreased work performance and more incidents. Rotation from day shift to night shift and its effect on shift workers was a special focus of the articles retained for review. Disturbed circadian rhythm in humans has been associated with a variety of mental and physical disorders and may negatively impact on work safety, performance, and productivity.

Administrative rationality and coping strategies in shift work.

PubMed

Lieber, Renato Rocha; Kvieska, Rodrigo Neiva; Delamaro, Maurício Cesar

2012-01-01

Shift work (SW) can affect worker health and productivity. Working at night, workers often accumulate fatigue and are less productive. In Brazil, laws have been drafted aiming to reduce night work and rotating shift hours. In order to slash costs, companies have been looking for new arrangements to improve productivity under these conditions. The purpose of this study was to examine management changes and their outcomes in a large glass factory located in an industrial region of Brazil. The results show that the management, seeking equal productivity among shifts, focused its efforts mainly on distributing employee expertise. The arrangement resulted in 12 different groups that combine to serve three fixed shifts. A same shift can be served by more than one group, and the members of a same group share days off on different days. There was no statistically significant productivity difference among the three shifts. The on-site examination showed that part of the production was held by the workers and transferred to the next shift in order for them to be able to meet the management's performance rate requirements. The finding shows how a Brazilian cultural trait (resistance without conflict) is used to drive coping in SW.

The human factors of implementing shift work in logging operations.

PubMed

Mitchell, D L; Gallagher, T V; Thomas, R E

2008-10-01

A fairly recent development in the forest industry is the use of shift work in logging in the southeastern U.S. Logging company owners are implementing shift work as an opportunity to increase production and potentially reduce the cost of producing each unit of wood, without consideration of the potential impacts on the logging crew. There are many documented physiological and psychological impacts on workers from shift work in a variety of industries, although few address forestry workers in the U.S. Semi-structured interviews were performed to gather information about how logging company owners were implementing shift work in seven southeastern states. Data collected during the interviews included employee turnover, shift hours, shift scheduling, safety considerations, and production impacts. Various work schedules were employed. The majority of the schedules encompassed less than 24 hours per day. Permanent and rotating shift schedules were found. None of the logging company owners used more than two crews in a 24-hour period. Additional safety precautions were implemented as a result of working after dark. No in-woods worker accidents or injuries were reported by any of those interviewed. Results indicate that a variety of work schedules can be successfully implemented in the southeastern logging industry.

Primary selection into shift work and change of cardiovascular risk profile.

PubMed

Yong, Mei; Germann, Christina; Lang, Stefan; Oberlinner, Christoph

2015-05-01

A potential "healthy shift worker effect" may bias the studied effect of shift work on health. The observed differences among shift and day workers in health behavior and health outcomes can be caused by: (i) primary selection, (ii) the influence from the shift work-related environment, and (iii) the impact of shift work. We aimed to study these potential sources. A cohort of 4754 male trainees who had finished their professional training and started their career in production in a chemical company between 1995 and 2012 was identified. Among them, 1348 (28%) were involved in rotating shift work and 3406 (72%) in day work. Information on health behavior and risk factors for cardiovascular diseases was retrieved from the medical examinations. This information was then compared (i) at the beginning of training, (ii) at the end of training, and (iii) 3 years after the employment, in relation to the working time. At the beginning of the training, the prevalence of smokers was higher among future shift workers (26% versus 21%), from 1995 to 2012. During the training and the first three years of employment, a marginal decline of systolic blood pressure and an elevation of triglyceride were related with shift work. No difference was found with respect to other risk factors for cardiovascular diseases. Our findings do not support a primary selection in favor of shift workers. An impact of shift work on the risk profile of cardiovascular diseases was not indicated in the observation period.

Influences on Dietary Choices during Day versus Night Shift in Shift Workers: A Mixed Methods Study

PubMed Central

Bonnell, Emily K.; Huggins, Catherine E.; Huggins, Chris T.; McCaffrey, Tracy A.; Palermo, Claire; Bonham, Maxine P.

2017-01-01

Shift work is associated with diet-related chronic conditions such as obesity and cardiovascular disease. This study aimed to explore factors influencing food choice and dietary intake in shift workers. A fixed mixed method study design was undertaken on a convenience sample of firefighters who continually work a rotating roster. Six focus groups (n = 41) were conducted to establish factors affecting dietary intake whilst at work. Dietary intake was assessed using repeated 24 h dietary recalls (n = 19). Interviews were audio recorded, transcribed verbatim, and interpreted using thematic analysis. Dietary data were entered into FoodWorks and analysed using Wilcoxon signed-rank test; p < 0.05 was considered significant. Thematic analysis highlighted four key themes influencing dietary intake: shift schedule; attitudes and decisions of co-workers; time and accessibility; and knowledge of the relationship between food and health. Participants reported consuming more discretionary foods and limited availability of healthy food choices on night shift. Energy intakes (kJ/day) did not differ between days that included a day or night shift but greater energy density (EDenergy, kJ/g/day) of the diet was observed on night shift compared with day shift. This study has identified a number of dietary-specific shift-related factors that may contribute to an increase in unhealthy behaviours in a shift-working population. Given the increased risk of developing chronic diseases, organisational change to support workers in this environment is warranted. PMID:28245625

Influences on Dietary Choices during Day versus Night Shift in Shift Workers: A Mixed Methods Study.

PubMed

Bonnell, Emily K; Huggins, Catherine E; Huggins, Chris T; McCaffrey, Tracy A; Palermo, Claire; Bonham, Maxine P

2017-02-26

Shift work is associated with diet-related chronic conditions such as obesity and cardiovascular disease. This study aimed to explore factors influencing food choice and dietary intake in shift workers. A fixed mixed method study design was undertaken on a convenience sample of firefighters who continually work a rotating roster. Six focus groups ( n = 41) were conducted to establish factors affecting dietary intake whilst at work. Dietary intake was assessed using repeated 24 h dietary recalls ( n = 19). Interviews were audio recorded, transcribed verbatim, and interpreted using thematic analysis. Dietary data were entered into FoodWorks and analysed using Wilcoxon signed-rank test; p < 0.05 was considered significant. Thematic analysis highlighted four key themes influencing dietary intake: shift schedule; attitudes and decisions of co-workers; time and accessibility; and knowledge of the relationship between food and health. Participants reported consuming more discretionary foods and limited availability of healthy food choices on night shift. Energy intakes (kJ/day) did not differ between days that included a day or night shift but greater energy density (ED energy , kJ/g/day) of the diet was observed on night shift compared with day shift. This study has identified a number of dietary-specific shift-related factors that may contribute to an increase in unhealthy behaviours in a shift-working population. Given the increased risk of developing chronic diseases, organisational change to support workers in this environment is warranted.

The impact of shift and night work on health related quality of life of working women: findings from the Korea Health Panel.

PubMed

Kim, Woorim; Kim, Tae Hyun; Lee, Tae-Hoon; Choi, Jae Woo; Park, Eun-Cheol

2016-11-28

Night and shift work status has been associated with health related quality of life (HRQoL) in economically active women. This study aimed to investigate the association between night or shift work status and HRQoL of economically active women and to further analyze how marital status interplays in the objected relationship. Data were from the Korea Health Panel, 2011 to 2013. A total of 2238 working women were included for analysis. Work status was categorized into day work, night work, and rotating shift work and its association with HRQoL, measured using the EuroQol-5D (EQ-5D) index, was investigated using the generalized estimating equation (GEE) model. Compared to the day work reference group, the night work group (β: -0.9757, P = 0.0202) and the rotating shift work group (β: -0.7947, P = 0.0363) showed decreases in EQ-5D scores. This trend was maintained regardless of marital status, although decreases in health related quality of life were particularly pronounced among night shift workers with a spouse. Night and rotating shift work status was associated with HRQoL of economically active women as individuals working night and rotating shifts showed decreases in EQ-5D scores compared to individuals working day shifts. The findings of this study signify the importance of monitoring the HRQoL status of women working night and rotating shifts as these individuals may be comparatively vulnerable to reduced HRQoL.

Fixed or Rotating Night Shift Work Undertaken by Women: Implications for Fertility and Miscarriage.

PubMed

Fernandez, Renae C; Marino, Jennifer L; Varcoe, Tamara J; Davis, Scott; Moran, Lisa J; Rumbold, Alice R; Brown, Hannah M; Whitrow, Melissa J; Davies, Michael J; Moore, Vivienne M

2016-03-01

This review summarizes the evidence concerning effects of night shift work on women's reproductive health, specifically difficulty in conceiving and miscarriage. We distinguish between fixed night shift and rotating night shift, as the population subgroups exposed, the social and biological mechanisms, and the magnitude of effects are likely to differ; of note, women working fixed night shift are known to have high tolerance for this schedule. We identified two relevant systematic reviews with meta-analyses and five additional studies. Night shift work may give rise to menstrual cycle disturbances, but effect sizes are imprecise. Endometriosis may be elevated in night shift workers, but evidence is only preliminary. Adequate data are lacking to assess associations between night shift work and infertility or time to pregnancy. The weight of evidence begins to point to working at night, whether in fixed or rotating shifts, as a risk factor for miscarriage. There are many methodological problems with this literature, with substantial variation in the definitions of night shift and schedule types making comparisons between studies difficult and pooling across studies questionable. Nevertheless, there appears to be grounds for caution and counselling where women have concerns about night shift work and their reproductive health. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

What roles do team climate, roster control, and work life conflict play in shiftworkers' fatigue longitudinally?

PubMed

Pisarski, Anne; Barbour, Jennifer P

2014-05-01

The study aimed to examine shiftworkers fatigue and the longitudinal relationships that impact on fatigue such as team climate, work life conflict, control of shifts and shift type in shift working nurses. We used a quantitative survey methodology and analysed data with a moderated hierarchical multiple regression. After matching across two time periods 18 months apart, the sample consisted of 166 nurses from one Australian hospital. Of these nurses, 61 worked two rotating day shifts (morning & afternoon/evening) and 105 were rotating shiftworkers who worked three shifts (morning afternoon/evening and nights). The findings suggest that control over shift scheduling can have significant effects on fatigue for both two-shift and three-shift workers. A significant negative relationship between positive team climate and fatigue was moderated by shift type. At both Time 1 and Time 2, work life conflict was the strongest predictor of concurrent fatigue, but over time it was not. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Association Between Rotating Night Shift Work and Risk of Coronary Heart Disease Among Women.

PubMed

Vetter, Céline; Devore, Elizabeth E; Wegrzyn, Lani R; Massa, Jennifer; Speizer, Frank E; Kawachi, Ichiro; Rosner, Bernard; Stampfer, Meir J; Schernhammer, Eva S

2016-04-26

Prospective studies linking shift work to coronary heart disease (CHD) have been inconsistent and limited by short follow-up. To determine whether rotating night shift work is associated with CHD risk. Prospective cohort study of 189,158 initially healthy women followed up over 24 years in the Nurses' Health Studies (NHS [1988-2012]: N = 73,623 and NHS2 [1989-2013]: N = 115,535). Lifetime history of rotating night shift work (≥3 night shifts per month in addition to day and evening shifts) at baseline (updated every 2 to 4 years in the NHS2). Incident CHD; ie, nonfatal myocardial infarction, CHD death, angiogram-confirmed angina pectoris, coronary artery bypass graft surgery, stents, and angioplasty. During follow-up, 7303 incident CHD cases occurred in the NHS (mean age at baseline, 54.5 years) and 3519 in the NHS2 (mean age, 34.8 years). In multivariable-adjusted Cox proportional hazards models, increasing years of baseline rotating night shift work was associated with significantly higher CHD risk in both cohorts. In the NHS, the association between duration of shift work and CHD was stronger in the first half of follow-up than in the second half (P=.02 for interaction), suggesting waning risk after cessation of shift work. Longer time since quitting shift work was associated with decreased CHD risk among ever shift workers in the NHS2 (P<.001 for trend). [table: see text] Among women who worked as registered nurses, longer duration of rotating night shift work was associated with a statistically significant but small absolute increase in CHD risk. Further research is needed to explore whether the association is related to specific work hours and individual characteristics.

Shift Work Disorder, Depression, and Anxiety in the Transition to Rotating Shifts: The Role of Sleep Reactivity

PubMed Central

Kalmbach, David A; Pillai, Vivek; Cheng, Philip; Arnedt, J Todd; Drake, Christopher L

2016-01-01

Objectives To investigate premorbid sleep reactivity as a vulnerability to incident shift work disorder and related changes in depression and anxiety following a transition to a rotating shifts work schedule. Methods This is a longitudinal study with two waves of data collection. The community-based sample included normal sleeping non-shift workers (N=96; 62.5% female; 47.9±13.3 yo) without a lifetime history of insomnia or baseline excessive daytime sleepiness who transitioned to rotating shift work one year later. Participants reported demographic characteristics, trait sleep reactivity on the Ford Insomnia Response to Stress Test, depression symptoms on the Quick Inventory of Depression Symptomatology, and anxiety symptoms on the Beck Anxiety Inventory. Shift work disorder was determined based on significant sleep disturbance and/or excessive sleepiness in the context of working a rotating shifts schedule. Results Analyses revealed that the odds were over five times greater for highly sleep reactive individuals to develop shift work disorder after transitioning to rotating shifts (OR=5.59, p=.04). Nearly 90% of shift work disorder sufferers were accurately identified as high risk at 1-y prior to disease onset. Furthermore, individuals who developed SWD reported greater increases in symptoms of depression and anxiety. Finally, analyses revealed significant indirect effects wherein high sleep reactivity increased risk for SWD, which led to greater severity of anxiety and depression symptoms. Conclusions The FIRST accurately identifies a focused target population in which the premorbid psychobiological processes complicit in SWD onset and progression, as well as shift work-related depression and anxiety changes, can be better investigated, thus improving future preventative efforts. PMID:26611952

What is the impact of shift work on the psychological functioning and resilience of nurses? An integrative review.

PubMed

Tahghighi, Mozhdeh; Rees, Clare S; Brown, Janie A; Breen, Lauren J; Hegney, Desley

2017-09-01

To synthesize existing research to determine if nurses who work shifts have poorer psychological functioning and resilience than nurses who do not work shifts. Research exploring the impact of shift work on the psychological functioning and resilience of nurses is limited compared with research investigating the impact of shifts on physical outcomes. Integrative literature review. Relevant databases were searched from January 1995-August 2016 using the combination of keywords: nurse, shift work; rotating roster; night shift; resilient; hardiness; coping; well-being; burnout; mental health; occupational stress; compassion fatigue; compassion satisfaction; stress; anxiety; depression. Two authors independently performed the integrative review processes proposed by Whittemore and Knafl and a quality assessment using the mixed-methods appraisal tool by Pluye et al. A total of 37 articles were included in the review (32 quantitative, 4 qualitative and 1 mixed-methods). Approximately half of the studies directly compared nurse shift workers with non-shift workers. Findings were grouped according to the following main outcomes: (1) general psychological well-being/quality of life; (2) Job satisfaction/burnout; (3) Depression, anxiety and stress; and (4) Resilience/coping. We did not find definitive evidence that shift work is associated with poorer psychological functioning in nurses. Overall, the findings suggest that the impact of shift work on nurse psychological functioning is dependent on several contextual and individual factors. More studies are required which directly compare the psychological outcomes and resilience of nurse shift workers with non-shift workers. © 2017 John Wiley & Sons Ltd.

A study comparing the hypnotic efficacies and residual effects on actual driving performance of midazolam 15 mg, triazolam 0.5 mg, temazepam 20 mg and placebo in shiftworkers on night duty

DOT National Transportation Integrated Search

1988-11-01

The purpose of the study was to determine the hypnotic efficacy and residual effects of three hypnotics administered for the treatment of transient insomnia in the day-sleep of rotating shift workers. The average duration of day-sleep in rotating shi...

Night Shift Work and Its Health Effects on Nurses.

PubMed

Books, Candie; Coody, Leon C; Kauffman, Ryan; Abraham, Sam

The purpose of this research was to study night shift work and its health effects on nurses. This was a quantitative study using descriptive design; it also incorporated three qualitative open-ended questions to complement the study. The data were collected using Survey Monkey, with an Internet-based confidential data collection tool. The population of relevance to this study was nurses employed in hospital settings in the United States. E-mail addresses and Facebook were used to recruit participants. Results indicated that there is an increased risk of sleep deprivation, family stressors, and mood changes because of working the night shift. Rotating shifts were mentioned as a major concern for night shift nurses. Respondents agreed that complaints about fatigue and fatigue-related illnesses in night shift workers were ignored. There was also a general perception among nurses working the night shift that sleep deprivation leads to negative health consequences including obesity; however, they were not as high a concern as rotating shifts or fatigue.

Quality of Life, Sleep, and Health of Air Traffic Controllers With Rapid Counterclockwise Shift Rotation.

PubMed

Sonati, Jaqueline Girnos; De Martino, Milva Maria Figueiredo; Vilarta, Roberto; da Silva Maciel, Érika; Sonati, Renato José Ferreira; Paduan, Paulo Cézar

2016-08-01

Rotating shiftwork is common for air traffic controllers and usually causes sleep deprivation, biological adaptations, and life changes for these workers. This study assessed quality of life, the sleep, and the health of 30 air traffic controllers employed at an international airport in Brazil. The objective was to identify health and quality of life concerns of these professionals. The results identified physical inactivity, overweight, excess body fat, low scores for physical and social relationships, and sleep deprivation for workers in all four workshifts. In conclusion, these workers are at risk for chronic non-transmittable diseases and compromised work performance, suggesting the need for more rest time before working nightshifts and work environments that stimulate physical activity and healthy diets. © 2016 The Author(s).

Measuring Light at Night and Melatonin Levels in Shift Workers: A Review of the Literature.

PubMed

Hunter, Claudia M; Figueiro, Mariana G

2017-07-01

Shift work, especially that involving rotating and night shifts, is associated with an increased risk of diseases, including cancer. Attempts to explain the association between shift work and cancer in particular have focused on the processes of melatonin production and suppression. One hypothesis postulates that exposure to light at night (LAN) suppresses melatonin, whose production is known to slow the development of cancerous cells, while another proposes that circadian disruption associated with shift work, and not just LAN, increases health risks. This review focuses on six studies that employed quantitative measurement of LAN and melatonin levels to assess cancer risks in shift workers. These studies were identified via searching the PubMed database for peer-reviewed, English-language articles examining the links between shift work, LAN, and disease using the terms light at night, circadian disruption, health, risk, cancer, shift work, or rotating shift. While the results indicate a growing consensus on the relationship between disease risks (particularly cancer) and circadian disruption associated with shift work, the establishment of a direct link between LAN and disease has been impeded by contradictory studies and a lack of consistent, quantitative methods for measuring LAN in the research to date. Better protocols for assessing personal LAN exposure are required, particularly those employing calibrated devices that measure and sample exposure to workplace light conditions, to accurately assess LAN's effects on the circadian system and disease. Other methodologies, such as measuring circadian disruption and melatonin levels in the field, may also help to resolve discrepancies in the findings.

The impact of shift work on the psychological and physical health of nurses in a general hospital: a comparison between rotating night shifts and day shifts.

PubMed

Ferri, Paola; Guadi, Matteo; Marcheselli, Luigi; Balduzzi, Sara; Magnani, Daniela; Di Lorenzo, Rosaria

2016-01-01

Shift work is considered necessary to ensure continuity of care in hospitals and residential facilities. In particular, the night shift is one of the most frequent reasons for the disruption of circadian rhythms, causing significant alterations of sleep and biological functions that can affect physical and psychological well-being and negatively impact work performance. The aim of this study was to highlight if shift work with nights, as compared with day work only, is associated with risk factors predisposing nurses to poorer health conditions and lower job satisfaction. This cross-sectional study was conducted from June 1, 2015 to July 31, 2015 in 17 wards of a general hospital and a residential facility of a northern Italian city. This study involved 213 nurses working in rotating night shifts and 65 in day shifts. The instrument used for data collection was the "Standard Shift Work Index," validated in Italian. Data were statistically analyzed. The response rate was 86%. The nurses engaged in rotating night shifts were statistically significantly younger, more frequently single, and had Bachelors and Masters degrees in nursing. They reported the lowest mean score in the items of job satisfaction, quality and quantity of sleep, with more frequent chronic fatigue, psychological, and cardiovascular symptoms in comparison with the day shift workers, in a statistically significant way. Our results suggest that nurses with rotating night schedule need special attention due to the higher risk for both job dissatisfaction and undesirable health effects.

Shift work disorder, depression, and anxiety in the transition to rotating shifts: the role of sleep reactivity.

PubMed

Kalmbach, David A; Pillai, Vivek; Cheng, Philip; Arnedt, J Todd; Drake, Christopher L

2015-12-01

The aim of this study is to investigate premorbid sleep reactivity as a vulnerability to incident shift work disorder (SWD), and related changes in depression as well as anxiety following a transition to a rotating shifts work schedule. This is a longitudinal study with two waves of data collection. The community-based sample included normal sleeping non-shift workers (N = 96; 62.5% female; 47.9 ± 13.3 years) without a lifetime history of insomnia or baseline excessive daytime sleepiness who transitioned to rotating shift work one year later. Participants reported demographic characteristics, trait sleep reactivity on the Ford Insomnia Response to Stress Test, depression symptoms on the Quick Inventory of Depression Symptomatology, and anxiety symptoms on the Beck Anxiety Inventory. SWD was determined based on significant sleep disturbance and/or excessive sleepiness in the context of working in a rotating-shift schedule. Analyses revealed that the odds were over five times greater for highly sleep-reactive individuals to develop SWD after transitioning to rotating shifts (OR = 5.59, p = 0.04). Nearly 90% of participants who suffered from SWD were accurately identified as high risk at one year before disease onset. Furthermore, individuals who developed SWD reported greater increases in symptoms of depression and anxiety. Finally, analyses revealed significant indirect effects wherein high sleep reactivity increased risk for SWD, which led to greater severity of anxiety and depression symptoms. The Ford Insomnia Response to Stress Test (FIRST) accurately identifies a focused target population in which the premorbid psychobiological processes complicit in SWD onset and progression, as well as shift work-related depression and anxiety changes, can be better investigated, thus improving future preventative efforts. Copyright © 2015 Elsevier B.V. All rights reserved.

Absence from work in relation to length and distribution of shift hours

PubMed Central

Walker, J.; Mare, Gwynneth de la

1971-01-01

Walker, J., and de la Mare, Gwynneth (1971). Brit. J. industr. Med., 28, 36-44. Absence from work in relation to length and distribution of shift hours. A long period on night shift or even permanent night work has sometimes been suggested for those on continuous shift work to allow circadian rhythms to adapt. As the weekly hours of work have been reduced there is some evidence that a permanent night shift is practical, and about 12% of all shift workers are on this type of work. However, the case for permanent night shift must be established on grounds of both effectiveness and acceptability. The present study compares the absence experience, including sickness absence, of permanent day workers and permanent night workers matched for age and job in three undertakings which contained a range of working conditions. The question of the relationship between absence from work and total hours worked including overtime has been reopened, and in comparing absence from work according to the type of shift the total hours worked must also be taken into account. The relationship between the average hours when a man was at work and the amount of absence was tested. The men in the three undertakings worked a wide range of voluntary overtime. The results showed that in two undertakings long-term absence, mainly sickness absence, was higher on the night shift than on the day shift; and, in the third, absence was about the same on the two shifts. As the work load was less in the two undertakings with a higher absence on the night shift it was suggested that selective factors were operating. These results may be contrasted to studies which have compared the absence of rotating shift workers and day workers. In all three undertakings there was a tendency for absence to be less among high overtime workers than among those who worked medium or small amounts of overtime, although the trends were not consistent. There was no evidence at all that high overtime and absence from work were positively associated. The implications of these results are discussed. PMID:5101167

Meta-analysis on shift work and risks of specific obesity types.

PubMed

Sun, M; Feng, W; Wang, F; Li, P; Li, Z; Li, M; Tse, G; Vlaanderen, J; Vermeulen, R; Tse, L A

2018-01-01

This systematic review and meta-analysis evaluated the associations between shift work patterns and risks of specific types of obesity. PubMed was searched until March 2017 for observational studies that examined the relationships between shift work patterns and obesity. Odds ratio for obesity was extracted using a fixed-effects or random-effects model. Subgroup meta-analyses were carried out for study design, specific obesity types and characteristics of shift work pattern. A total of 28 studies were included in this meta-analysis. The overall odds ratio of night shift work was 1.23 (95% confidence interval = 1.17-1.29) for risk of obesity/overweight. Cross-sectional studies showed a higher risk of 1.26 than those with the cohort design (risk ratio = 1.10). Shift workers had a higher frequency of developing abdominal obesity (odds ratio = 1.35) than other obesity types. Permanent night workers demonstrated a 29% higher risk than rotating shift workers (odds ratio 1.43 vs. 1.14). This meta-analysis confirmed the risks of night shift work for the development of overweight and obesity with a potential gradient association suggested, especially for abdominal obesity. Modification of working schedules is recommended, particularly for prolonged permanent night work. More accurate and detailed measurements on shift work patterns should be conducted in future research. © 2017 World Obesity Federation.

Effects of direction of rotation in continuous and discontinuous 8 hour shift systems

PubMed Central

Tucker, P.; Smith, L.; Macdonald, I.; Folkard, S.

2000-01-01

OBJECTIVES—Previous research has produced conflicting evidence on the relative merits of advancing and delaying shift systems. The current study assessed the effects of the direction of shift rotation within 8 hour systems, upon a range of measures including sleep, on shift alertness, physical health, and psychological wellbeing.
METHODS—An abridged version of the standard shiftwork index which included retrospective alertness ratings was completed by four groups of industrial shiftworkers on relatively rapidly rotating 8 hour systems (n=611). Two groups worked continuous systems that were either advancing or delaying; the other two groups worked discontinuous systems that were either advancing or delaying.
RESULTS—Few effects were found of direction of rotation on chronic measures of health and wellbeing, even when the systems incorporated "quick returns" (a break of only 8 hours when changing from one shift to another). This was despite the use of measures previously shown to be sensitive to the effects of a broad range of features of shift systems. However, advancing continuous systems seemed to be associated with marginally steeper declines in alertness across the shift (F (3,1080)=2.87, p<0.05). They were also associated with shorter sleeps between morning shifts (F (1,404)=4.01, p<0.05), but longer sleeps between afternoons (F (1,424)=4.16, p<0.05).
CONCLUSIONS—The absence of negative effects of advancing shifts upon the chronic outcome measures accorded with previous evidence that advancing shifts may not be as harmful as early research indicated. However, this interpretation is tempered by the possibility that difficult shift systems self select those workers most able to cope with their deleterious effects. The presence of quick returns in advancing continuous systems seemed to impact upon some of the acute measures such as duration of sleep, although the associated effects on alertness seemed to be marginal.


Keywords: shift rotation; health; alertness PMID:10984340

A Comparative Study of Shift Work Effects and Injuries among Nurses Working in Rotating Night and Day Shifts in a Tertiary Care Hospital of North India.

PubMed

Verma, Anjana; Kishore, Jugal; Gusain, Shobha

2018-01-01

Shift work can have an impact on the physical and psychological well-being of the healthcare worker, affecting patients as well as their own safety at the workplace. This study was conducted to compare the health outcomes and injuries, along with associated risk factors between the nurses working in rotating night shift (RNS) as compared to day shift (DS) only. It was a cross-sectional study conducted from June to November 2016 in a tertiary care hospital of Delhi. It involved 275 nurses working in RNS and 275 nurses from DS of various departments, selected through simple random sampling. Standard Shift Work Index Questionnaire (SSI) was used as the study instrument, with selected variables (according to objectives of the study). Data were analyzed using descriptive statistics, Chi-square, t -test, and multivariate regression. Female nurses had more sleep disturbance, fatigue, and poor psychological health. Working on a contractual basis, RNS, and living outside the hospital campus were associated with higher odds of having needle stick injury (NSI). The nurses working in RNSs were found to have significantly lower mean scores in job satisfaction ( p = 0.04), sleep ( p < 0.001), and psychological well-being ( p = 0.047) as compared to DS workers. Health outcomes among nurses working in RNSs call for the interventions, focused on various factors which can be modified to provide supportive and safer working environment.

Shift work, job strain and changes in the body mass index among women: a prospective study.

PubMed

Fujishiro, Kaori; Lividoti Hibert, Eileen; Schernhammer, Eva; Rich-Edwards, Janet W

2017-06-01

The effects of job strain and shift work on weight gain have not been studied jointly. Cross-sectional and longitudinal studies on shift work and weight gain have reported different results. This study examines potential effect modification by job strain on the link between shift work and weight gain, and concurrent and delayed effects of shift work on weight gain. Data came from 52 622 women who participated in the Nurses' Health Study II, a prospective cohort study. Using linear regression, we modelled change in body mass index (BMI) over 4 years as a function of change in job strain, cumulative exposure to rotating night shift previously and during the 4 years (ie, previous and concurrent exposures) and the interaction between job strain and concurrent shift work exposure. Age, race/ethnicity, pregnancy history, baseline BMI, job types and health behaviours at baseline were controlled for. Job strain and rotating shift work, concurrent and previous, all had independent associations with BMI change during the 4-year period. There was no evidence for effect modification by job strain. Concurrent and previous exposures to rotating night shift had different associations with BMI change: an inverted U-shape for concurrent exposure (ranging from 0.01 to 0.14 kg/m 2 increase), a dose-response for previous exposure (-0.02 to 0.09 kg/m 2 ). Job strain and rotating night shift work have independent contributions to weight gain. Reducing job strain and supporting night shift workers are both important intervention goals. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Integrated ergonomics approach toward designing night and shift work in developing countries based on experiences in Bali, Indonesia.

PubMed

Manuaba, A

2001-12-01

Recently, the effort in carrying out an integrated ergonomics approach known as "SHIP" (systemic, holistic, interdisciplinary and participatory) approach has been intensively undertaken in Bali with the aim of sustaining improvements being done. The People's Consultative Assembly of the Republic of Indonesia issued for the 1999-2004 period a "SHIP" Act on the Macro Guidelines of Tourism Development in which ergonomics and other factors must be considered comprehensively to attain sustainable development in tourism. Therefore the night and shift work that is recently increasingly applied in the tourism industry must also be designed and organized through this approach. In fact, however, economic factors have still been the predominant reason for workers to accept any type of night and shift work decided by the management, without taking into account possible impacts and consequences. For example, rapid forward rotation schemes seem more adapted to the hotel industry instead of traditional 6-6-6 rotation. Further, inter-city bus drivers are approved to work a 24-hour shift followed by one day off. These drivers often work an additional risky night shift after two consecutive night shifts so as to meet needed expenses for the family. Cultural or religious activities still presented constraints for workers as they carried out subsequently the night work. Therefore, proactive steps should be taken in a timely manner through the integrated SHIP approach in designing night and shift work so as to achieve work schedules compatible with both social life of shiftworkers and business concerns.

Shift work at a modern offshore drilling rig.

PubMed

Rodrigues, V F; Fischer, F M; Brito, M J

2001-12-01

The oil and gas exploration and production offshore units are classified as hazardous installations. Work in these facilities is complex, confined and associated with a wide range of risks. The continuous operation is secured by various shift work patterns. The objective of this study was to evaluate how offshore drilling workers perceived shift work at high seas and its impacts on their life and working conditions. The main features of the studied offshore shift work schedules are: long time on board (14 to 28 days), extended shifts (12 hours or more per day), slow rotation (7 to 14 days in the same shift), long sequence of days on the night shift (7 to 14 days in a row) and the extra-long extended journey (18 hours) on shift change and landing days. Interviews revealed a wide range of stressors caused by the offshore shift work, as well as difficulties to conciliate work with family life. It was observed that changes of the family model, leading to role conflicts and social isolation, work in a hazardous environment, perceiving poor sleep when working at night shifts and the imbalance between the expected and actual rewards are the major stressors for the offshore drilling workers.

Night Shift Work, Genetic Risk, and Type 2 Diabetes in the UK Biobank.

PubMed

Vetter, Céline; Dashti, Hassan S; Lane, Jacqueline M; Anderson, Simon G; Schernhammer, Eva S; Rutter, Martin K; Saxena, Richa; Scheer, Frank A J L

2018-04-01

To examine the effects of past and current night shift work and genetic type 2 diabetes vulnerability on type 2 diabetes odds. In the UK Biobank, we examined associations of current ( N = 272,214) and lifetime ( N = 70,480) night shift work exposure with type 2 diabetes risk (6,770 and 1,191 prevalent cases, respectively). For 180,704 and 44,141 unrelated participants of European ancestry (4,002 and 726 cases, respectively) with genetic data, we assessed whether shift work exposure modified the relationship between a genetic risk score (comprising 110 single-nucleotide polymorphisms) for type 2 diabetes and prevalent diabetes. Compared with day workers, all current night shift workers were at higher multivariable-adjusted odds for type 2 diabetes (none or rare night shifts: odds ratio [OR] 1.15 [95% CI 1.05-1.26]; some nights: OR 1.18 [95% CI 1.05-1.32]; and usual nights: OR 1.44 [95% CI 1.19-1.73]), except current permanent night shift workers (OR 1.09 [95% CI 0.93-1.27]). Considering a person's lifetime work schedule and compared with never shift workers, working more night shifts per month was associated with higher type 2 diabetes odds (<3/month: OR 1.24 [95% CI 0.90-1.68]; 3-8/month: OR 1.11 [95% CI 0.90-1.37]; and >8/month: OR 1.36 [95% CI 1.14-1.62]; P trend = 0.001). The association between genetic type 2 diabetes predisposition and type 2 diabetes odds was not modified by shift work exposure. Our findings show that night shift work, especially rotating shift work including night shifts, is associated with higher type 2 diabetes odds and that the number of night shifts worked per month appears most relevant for type 2 diabetes odds. Also, shift work exposure does not modify genetic risk for type 2 diabetes, a novel finding that warrants replication. © 2018 by the American Diabetes Association.

Nurses' sleep quality, work environment and quality of care in the Spanish National Health System: observational study among different shifts

PubMed Central

Gómez-García, Teresa; Ruzafa-Martínez, María; Fuentelsaz-Gallego, Carmen; Madrid, Juan Antonio; Rol, Maria Angeles; Martínez-Madrid, María José; Moreno-Casbas, Teresa

2016-01-01

Objective The main objective of this study was to determine the relationship between the characteristics of nurses' work environments in hospitals in the Spanish National Health System (SNHS) with nurse reported quality of care, and how care was provided by using different shifts schemes. The study also examined the relationship between job satisfaction, burnout, sleep quality and daytime drowsiness of nurses and shift work. Methods This was a multicentre, observational, descriptive, cross-sectional study, centred on a self-administered questionnaire. The study was conducted in seven SNHS hospitals of different sizes. We recruited 635 registered nurses who worked on day, night and rotational shifts on surgical, medical and critical care units. Their average age was 41.1 years, their average work experience was 16.4 years and 90% worked full time. A descriptive and bivariate analysis was carried out to study the relationship between work environment, quality and safety care, and sleep quality of nurses working different shift patterns. Results 65.4% (410) of nurses worked on a rotating shift. The Practice Environment Scale of the Nursing Work Index classification ranked 20% (95) as favourable, showing differences in nurse manager ability, leadership and support between shifts (p=0.003). 46.6% (286) were sure that patients could manage their self-care after discharge, but there were differences between shifts (p=0.035). 33.1% (201) agreed with information being lost in the shift change, showing differences between shifts (p=0.002). The Pittsburgh Sleep Quality Index reflected an average of 6.8 (SD 3.39), with differences between shifts (p=0.017). Conclusions Nursing requires shift work, and the results showed that the rotating shift was the most common. Rotating shift nurses reported worse perception in organisational and work environmental factors. Rotating and night shift nurses were less confident about patients' competence of self-care after discharge. The most common nursing care omissions reported were related to nursing care plans. For the Global Sleep Quality score, difference were found between day and night shift workers. PMID:27496241

The correlation between urinary 5-hydroxyindoleacetic acid and sperm quality in infertile men and rotating shift workers.

PubMed

Ortiz, Águeda; Espino, Javier; Bejarano, Ignacio; Lozano, Graciela M; Monllor, Fabián; García, Juan F; Pariente, José A; Rodríguez, Ana B

2010-11-08

Serotonin is a neurotransmitter that modulates a wide range of neuroendocrine functions. However, excessive circulating serotonin levels may induce harmful effects in the male reproductive system. The objective of this study was to evaluate whether the levels of urinary 5-hydroxyindoleacetic acid (5-HIIA), a major serotonin metabolite, correlate with different classical seminal parameters. Human ejaculates were obtained from 40 men attending infertility counselling and rotating shift workers by masturbation after 4-5 days of abstinence. Urinary 5- HIIA concentration was quantified by using a commercial ELISA kit. Forward motility was assessed by a computer-aided semen analysis (CASA) system. Sperm concentration was determined using the haemocytometer method. Sperm morphology was evaluated after Diff-Quik staining, while sperm vitality was estimated after Eosin-Nigrosin vital staining. Our results show that urinary 5-HIIA levels obtained from a set of 20 volunteers negatively correlated with sperm concentration, forward motility, morphology normal range and sperm vitality. On the other hand, we checked the relationship between male infertility and urinary 5-HIIA levels in 20 night shift workers. Thus, urinary 5-HIIA levels obtained from 10 recently-proven fathers were significantly lower than those found in 10 infertile males. Additionally, samples from recent fathers exhibited higher sperm concentration, as well as better forward motility and normal morphology rate. In the light of our findings, we concluded that high serotonin levels, indirectly measured as urinary 5-HIIA levels, appear to play a role as an infertility determinant in male subjects.

Shift work and colorectal cancer risk in the MCC-Spain case-control study.

PubMed

Papantoniou, Kyriaki; Castaño-Vinyals, Gemma; Espinosa, Ana; Turner, Michelle C; Alonso-Aguado, Maria Henar; Martin, Vicente; Aragonés, Nuria; Pérez-Gómez, Beatriz; Pozo, Benito Mirón; Gómez-Acebo, Inés; Ardanaz, Eva; Altzibar, Jone M; Peiro, Rosana; Tardon, Adonina; Lorca, José Andrés; Chirlaque, Maria Dolores; García-Palomo, Andrés; Jimenez-Moleon, Jose Juan; Ierssen, Trinidad; Ederra, Maria; Amiano, Pilar; Pollan, Marina; Moreno, Victor; Kogevinas, Manolis

2017-05-01

Objectives Shift work that involves circadian disruption has been associated with a higher cancer risk. Most epidemiological studies to date have focused on breast cancer risk and evidence for other common tumors is limited. We evaluated the risk for colorectal cancer (CRC) in relation to shift work history in a population-based case-control study in Spain. Methods This analysis included 1626 incident CRC cases and 3378 randomly selected population controls of both sexes, enrolled in 11 regions of Spain. Sociodemographic and lifestyle information was assessed in face-to-face interviews. Shift work was assessed in detail throughout lifetime occupational history. We estimated the risk of colon and rectal cancer associated with rotating and permanent shift work (ever, cumulative duration, age of first exposure) using unconditional logistic regression analysis adjusting for potential confounders. Results Having ever performed rotating shift work (morning, evening and/or night) was associated with an increased risk for CRC [odds ratio (OR) 1.22, 95% confidence interval (95% CI) 1.04-1.43], as compared to day workers. Having ever worked permanent night shifts (≥3 nights/month) was not associated with CRC risk (OR 0.79, 95% CI 0.62-1.00). OR increased with increasing lifetime cumulative duration of rotating shift work (P-value for trend 0.005) and were highest among subjects in the top quartiles of exposure (3 rd quartile, 20-34 years, OR 1.38, 95%CI 1.06-1.81; 4 th quartile, ≥35 years, OR 1.36, 95% CI 1.02-1.79). Conclusions These data suggest that rotating shift work may increase the risk of CRC especially after long-term exposures.

Rotating Night-Shift Work and Lung Cancer Risk Among Female Nurses in the United States

PubMed Central

Schernhammer, Eva S.; Feskanich, Diane; Liang, Geyu; Han, Jiali

2013-01-01

The risk of lung cancer among night-shift workers is unknown. Over 20 years of follow-up (1988–2008), we documented 1,455 incident lung cancers among 78,612 women in the Nurses' Health Study. To examine the relationship between rotating night-shift work and lung cancer risk, we used multivariate Cox proportional hazard models adjusted for detailed smoking characteristics and other risk factors. We observed a 28% increased risk of lung cancer among women with 15 or more years spent working rotating night shifts (multivariate relative risk (RR) = 1.28, 95% confidence interval (CI): 1.07, 1.53; Ptrend = 0.03) compared with women who did not work any night shifts. This association was strongest for small-cell lung carcinomas (multivariate RR = 1.56, 95% CI: 0.99, 2.47; Ptrend = 0.03) and was not observed for adenocarcinomas of the lung (multivariate RR = 0.91, 95% CI: 0.67, 1.24; Ptrend = 0.40). Further, the increased risk associated with 15 or more years of rotating night-shift work was limited to current smokers (RR = 1.61, 95% CI: 1.21, 2.13; Ptrend < 0.001), with no association seen in nonsmokers (Pinteraction = 0.03). These results suggest that there are modestly increased risks of lung cancer associated with extended periods of night-shift work among smokers but not among nonsmokers. Though it is possible that this observation was residually confounded by smoking, our findings could also provide evidence of circadian disruption as a “second hit” in the etiology of smoking-related lung tumors. PMID:24049158

Descriptive Study of Occupational Accidents and their Causes among Electricity Distribution Company Workers at an Eight-year Period in Iran

PubMed Central

Rahmani, Abdolrasoul; Khadem, Monireh; Madreseh, Elham; Aghaei, Habib-Allah; Raei, Mehdi; Karchani, Mohsen

2013-01-01

Background Occupational accidents are unplanned events that cause damage. The socio-economic impacts and human costs of accidents are tremendous around the world. Many fatalities happen every year in workplaces such as electricity distribution companies. Some electrical injuries are electrocution, electric shock, and burns. This study was conducted in an electricity distribution company (with rotational 12-hour shift work) in Iran during an 8-year period to survey descriptive factors of injuries. Methods Variables collected included accident time, age of injured worker, employment type, work experience, injury cause, educational background, and other information about accidents. Results Results indicated that most of the accidents occurred in summer, and 51.3% were during shift work. Worker negligence (malpractice) was the cause of 75% of deaths. Type of employment had a significant relationship with type of injuries (p < 0.05). Most injuries were electrical burns. Conclusion High rate of accidents in summer may be due to the warm weather or insufficient professional skills in seasonal workers. Shift workers are at risk of sleep complaints leading to a high rate of work injuries. Acquiring knowledge about safety was related to job experiences. Temporary workers have no chance to work all year like permanent workers, therefore impressive experiences may be less in them. Because the lack of protective equipment and negligence are main causes of accidents, periodical inspections in workshops are necessary. PMID:24106647

Coronary artery atherosclerosis associated with shift work in chemical plant workers by using coronary CT angiography.

PubMed

Kang, WonYang; Park, Won-Ju; Jang, Keun-Ho; Kim, Soo-Hyeon; Gwon, Do-Hyeong; Lim, Hyeong-Min; Ahn, Ji-Sung; Moon, Jai-Dong

2016-08-01

The aim of this study was to investigate whether shift work is related to elevated risk of coronary artery disease (CAD) by determining the coronary artery calcium (CAC) score and the presence of coronary artery stenosis by using coronary artery CT angiography (CCTA). In this study, 110 male workers participated and underwent a CCTA examination for CAC scoring, which represents coronary artery plaque, and were evaluated for luminal stenosis. All of the participants were working in the same chemical plant, of whom 70 worked day shifts and 40 worked rotating shifts. In a multivariate logistic regression analysis, including age, smoking status, alcohol consumption, regular exercise and waist circumference, shift work was associated with a 2.89-fold increase in the odds of developing coronary plaque compared with day work (OR, 2.89; 95% CI 1.07 to 7.82). The association between shift work and coronary plaque was strong after adjustment for age, low-density lipoprotein cholesterol, hypertension and diabetes mellitus (OR, 2.92; 95% CI 1.02 to 8.33). In addition, the number of years of shift work employment was associated with coronary plaque. However, no association was found between shift work and coronary artery stenosis. Shift work could induce CAD onset via the atherosclerotic process, and shift work employment duration was associated with an increased risk of atherosclerosis in male workers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

The association between shift work and sick leave: a systematic review

PubMed Central

van Drongelen, Alwin; Holte, Kari Anne; Labriola, Merete; Lund, Thomas; van Mechelen, Willem; van der Beek, Allard J

2012-01-01

Shift work is associated with a number of negative health outcomes, although it is not known whether it is associated with sick leave. This systematic review therefore aimed to determine whether an association exists between shift work and sick leave. A systematic literature search was conducted in six databases on observational studies. Two reviewers independently selected relevant articles and appraised methodological quality. Data extraction was performed independently by review couples. Articles were categorised according to shift work characteristics and summarised using a levels of evidence synthesis. In total, the search strategy yielded 1207 references, of which 24 studies met the inclusion criteria. Nine studies were appraised as high quality and used in the levels of evidence synthesis. Two high quality longitudinal studies found a positive association between fixed evening shifts and longer sick leave for female healthcare workers. The evidence was assessed as strong. Evidence was inconclusive for rotating shifts, shift work including nights, for fixed night work, and for 8-hour and 12-hour shifts. The association found between evening work and sick leave in female healthcare workers implies that the association between shift work and sick leave might be schedule and population specific. To study the association further, more high quality studies are necessary that assess and adjust for detailed shift work exposure. PMID:22767871

Rest requirements and rest management of personnel in shift work

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hammell, B.D.; Scheuerle, A.

1995-12-31

A difficulty-weighted shift assignment scheme is proposed for use in prolonged and strenuous field operations such as emergency response, site testing, and short term hazardous waste remediation projects. The purpose of the work rotation plan is to increase productivity, safety, and moral of workers. Job weighting is accomplished by assigning adjustments to the mental and physical intensity of the task, the protective equipment worn, and the climatic conditions. The plan is based on medical studies of sleep deprivation, the effects of rest adjustments, and programs to reduce sleep deprivation and normalize shift schedules.

The effects of shift work and time of day on fine motor control during handwriting.

PubMed

Hölzle, Patricia; Hermsdörfer, Joachim; Vetter, Céline

2014-01-01

Handwriting is an elaborate and highly automatised skill relying on fine motor control. In laboratory conditions handwriting kinematics are modulated by the time of day. This study investigated handwriting kinematics in a rotational shift system and assessed whether similar time of day fluctuations at the work place can be observed. Handwriting performance was measured in two tasks of different levels of complexity in 34 shift workers across morning (6:00-14:00), evening (14:00-22:00) and night shifts (22:00-6:00). Participants were tested during all three shifts in 2-h intervals with mobile testing devices. We calculated average velocity, script size and writing frequency to quantify handwriting kinematics and fluency. Average velocity and script size were significantly affected by the shift work schedule with the worst performance during morning shifts and the best performance during evening shifts. Our data are of high economic relevance as fine motor skills are indispensable for accurate and effective production at the work place. Handwriting is one of the most complex fine motor skills in humans, which is frequently performed in daily life. In this study, we tested handwriting repeatedly at the work place in a rotational shift system. We found slower handwriting velocity and reduced script size during morning shifts.

Oxidative Stress and Depression among Male Shift Workers in Shahid Tondgouyan Refinery.

PubMed

Khajehnasiri, Farahnaz; Akhondzadeh, Shahin; Mortazavi, Seyed Bagher; Allameh, Abdolamir; Khavanin, Ali; Zamanian, Zahra

2014-04-01

The aim of this study was to determine the oxidative stress; serum level of Total Antioxidant Capacity (TAC)and Malondialdehyde (MDA) level and the depression score among the depressed rotational shift workers in Shahid Tondgouyan Refinery in Tehran (Iran). A cross-sectional study was conducted among all the 189 shift workers in Shahid Tondgouyan oil refinery who were eligible to participate in the study. They did not take any antidepressants for two months or any supplements for two weeks prior to the study entry. Written consent was obtained from the participants. 21- Item Beck Depression Inventory was used to measure the depression level. Furthermore, body weight, height and systolic and diastolic blood pressure were collected from all the participants. The levels of Total Antioxidant Capacity (TAC) and Malondialdehyde (MDA) were measured by 8 ml fasting blood sample. MDA was determined by thiobarbituric acid reaction. Serum total antioxidants were measured using the spectrophotometric ABTS. In the ABTS test, 2,2'-azinobis (3-ethylbenzthiazoline-6-acid) (ABTS) is converted into its radical cation (ABTS•+) by addition of sodium persulphate. This blue-green radical cation absorbs light at 734 nm. ABTS•+ is reactive towards most antioxidants. Descriptive statistics, ANOVA, ANCOVA and regression tests and correlation were used to analyze the data using SPSS software version 16. The age of the participants ranged from 21 to 52 years. The mean age of the participants was 30.58 year (±6.97yr). Of all the participants, 28% (n= 53) had no depression symptoms (depression score between 0 and 9), 65.1% (n=123) were categorized as having mild depression (depression score between 10 and 18) and 6.9% (n=13) were categorized as having moderate depression (depression score between 19 and 29). The participants' BMI ranged from 15.9 to 34.3; the mean BMI of the participants was 24.82 kg/m(2) (+ 3.81 kg/m(2)). The mean of the serum TAC level was 2.51 (± 0.56) mg/dl, and the mean serum MDA level was 3.67(± 1.08) μmol/l. There was a significant difference in the mean TAC concentration between the non-depressed group and the group with mild depression (p=0.029). Depression was associated with reduced mean TAC concentration and an increase in MDA level. There was a linear relationship between the depression score and shift work experience among the rotational shift workers, which showed a high level of stress and depression among the shift-workers.

Task rotation in an underground coal mine: A pilot study.

PubMed

Jones, Olivia F; James, Carole L

2018-01-01

Task rotation is used to decrease the risk of workplace injuries and improve work satisfaction. To investigate the feasibility, benefits and challenges of implementing a task rotation schedule within an underground coalmine in NSW, Australia. A mixed method case control pilot study with the development and implementation of a task rotation schedule for 6 months with two work crews. A questionnaire including The Nordic Musculoskeletal Questionnaire, The Need for Recovery after Work Scale, and The Australian WHOQOL- BREF Australian Edition was used to survey workers at baseline, 3 and 6 months. A focus group was completed with the intervention crew and management at the completion of the study. In total, twenty-seven participants completed the survey. Significant improvements in the psychological and environmental domains of the WHOQOL-BREF questionnaire were found in the intervention crew. Musculoskeletal pain was highest in the elbow, lower back and knee, and fatigue scores improved, across both groups. The intervention crew felt 'mentally fresher', 'didn't do the same task twice in a row', and 'had more task variety which made the shift go quickly'. Task rotation was positively regarded, with psychological benefits identified. Three rotations during a 9-hour shift were feasible and practical in this environment.

Nurses' sleep quality, work environment and quality of care in the Spanish National Health System: observational study among different shifts.

PubMed

Gómez-García, Teresa; Ruzafa-Martínez, María; Fuentelsaz-Gallego, Carmen; Madrid, Juan Antonio; Rol, Maria Angeles; Martínez-Madrid, María José; Moreno-Casbas, Teresa

2016-08-05

The main objective of this study was to determine the relationship between the characteristics of nurses' work environments in hospitals in the Spanish National Health System (SNHS) with nurse reported quality of care, and how care was provided by using different shifts schemes. The study also examined the relationship between job satisfaction, burnout, sleep quality and daytime drowsiness of nurses and shift work. This was a multicentre, observational, descriptive, cross-sectional study, centred on a self-administered questionnaire. The study was conducted in seven SNHS hospitals of different sizes. We recruited 635 registered nurses who worked on day, night and rotational shifts on surgical, medical and critical care units. Their average age was 41.1 years, their average work experience was 16.4 years and 90% worked full time. A descriptive and bivariate analysis was carried out to study the relationship between work environment, quality and safety care, and sleep quality of nurses working different shift patterns. 65.4% (410) of nurses worked on a rotating shift. The Practice Environment Scale of the Nursing Work Index classification ranked 20% (95) as favourable, showing differences in nurse manager ability, leadership and support between shifts (p=0.003). 46.6% (286) were sure that patients could manage their self-care after discharge, but there were differences between shifts (p=0.035). 33.1% (201) agreed with information being lost in the shift change, showing differences between shifts (p=0.002). The Pittsburgh Sleep Quality Index reflected an average of 6.8 (SD 3.39), with differences between shifts (p=0.017). Nursing requires shift work, and the results showed that the rotating shift was the most common. Rotating shift nurses reported worse perception in organisational and work environmental factors. Rotating and night shift nurses were less confident about patients' competence of self-care after discharge. The most common nursing care omissions reported were related to nursing care plans. For the Global Sleep Quality score, difference were found between day and night shift workers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

A retrospective cohort study of shift work and risk of cancer-specific mortality in German male chemical workers.

PubMed

Yong, Mei; Nasterlack, Michael; Messerer, Peter; Oberlinner, Christoph; Lang, Stefan

2014-02-01

Human evidence of carcinogenicity concerning shift work is inconsistent. In a previous study, we observed no elevated risk of total mortality in shift workers followed up until the end of 2006. The present study aimed to investigate cancer-specific mortality, relative to shift work. The cohort consisted of male production workers (14,038 shift work and 17,105 day work), employed at BASF Ludwigshafen for at least 1 year between 1995 and 2005. Vital status was followed from 2000 to 2009. Cause-specific mortality was obtained from death certificates. Exposure to shift work was measured both as a dichotomous and continuous variable. While lifetime job history was not available, job duration in the company was derived from personal data, which was then categorized at the quartiles. Cox proportional hazard model was used to adjust for potential confounders, in which job duration was treated as a time-dependent covariate. Between 2000 and 2009, there were 513 and 549 deaths among rotating shift and day work employees, respectively. Risks of total and cancer-specific mortalities were marginally lower among shift workers when taking age at entry and job level into consideration and were statistically significantly lower when cigarette smoking, alcohol intake, job duration, and chronic disease prevalence at entry to follow-up were included as explanatory factors. With respect to mortality risks in relation to exposure duration, no increased risks were found in any of the exposure groups after full adjustment and there was no apparent trend suggesting an exposure-response relation with duration of shift work. The present analysis extends and confirms our previous finding of no excess risk of mortality associated with work in the shift system employed at BASF Ludwigshafen. More specifically, there is also no indication of an increased risk of mortality due to cancer.

The correlation between urinary 5-hydroxyindoleacetic acid and sperm quality in infertile men and rotating shift workers

PubMed Central

2010-01-01

Background Serotonin is a neurotransmitter that modulates a wide range of neuroendocrine functions. However, excessive circulating serotonin levels may induce harmful effects in the male reproductive system. The objective of this study was to evaluate whether the levels of urinary 5-hydroxyindoleacetic acid (5-HIIA), a major serotonin metabolite, correlate with different classical seminal parameters. Methods Human ejaculates were obtained from 40 men attending infertility counselling and rotating shift workers by masturbation after 4-5 days of abstinence. Urinary 5- HIIA concentration was quantified by using a commercial ELISA kit. Forward motility was assessed by a computer-aided semen analysis (CASA) system. Sperm concentration was determined using the haemocytometer method. Sperm morphology was evaluated after Diff-Quik staining, while sperm vitality was estimated after Eosin-Nigrosin vital staining. Results Our results show that urinary 5-HIIA levels obtained from a set of 20 volunteers negatively correlated with sperm concentration, forward motility, morphology normal range and sperm vitality. On the other hand, we checked the relationship between male infertility and urinary 5-HIIA levels in 20 night shift workers. Thus, urinary 5-HIIA levels obtained from 10 recently-proven fathers were significantly lower than those found in 10 infertile males. Additionally, samples from recent fathers exhibited higher sperm concentration, as well as better forward motility and normal morphology rate. Conclusions In the light of our findings, we concluded that high serotonin levels, indirectly measured as urinary 5-HIIA levels, appear to play a role as an infertility determinant in male subjects. PMID:21059225

Shift work and cancer risk: potential mechanistic roles of circadian disruption, light at night, and sleep deprivation.

PubMed

Haus, Erhard L; Smolensky, Michael H

2013-08-01

Shift work that includes a nighttime rotation has become an unavoidable attribute of today's 24-h society. The related disruption of the human circadian time organization leads in the short-term to an array of jet-lag-like symptoms, and in the long-run it may contribute to weight gain/obesity, metabolic syndrome/type II diabetes, and cardiovascular disease. Epidemiologic studies also suggest increased cancer risk, especially for breast cancer, in night and rotating female shift workers. If confirmed in more controlled and detailed studies, the carcinogenic effect of night and shift work will constitute additional serious medical, economic, and social problems for a substantial proportion of the working population. Here, we examine the possible multiple and interconnected cancer-promoting mechanisms as a consequence of shift work, i.e., repeated disruption of the circadian system, pineal hormone melatonin suppression by exposure to light at night, sleep-deprivation-caused impairment of the immune system, plus metabolic changes favoring obesity and generation of proinflammatory reactive oxygen species. Copyright © 2012 Elsevier Ltd. All rights reserved.

Estimating occupational exposure to carcinogens in Quebec.

PubMed

Labrèche, France; Duguay, Patrice; Ostiguy, Claude; Boucher, Alexandre; Roberge, Brigitte; Peters, Cheryl E; Demers, Paul A

2013-09-01

We estimated the extent of exposure to occupational carcinogens in Quebec, Canada, to help raise awareness of occupational cancers. Proportions of workers exposed to 21 recognized and 17 probable carcinogens (according to Quebec occupational health regulation and the International Agency for Research on Cancer [IARC] classification) were extracted from various sources: workplace monitoring data, research projects, a population survey, radiation protection data, exposure estimates from the Carcinogen Exposure Canada (CAREX Canada) Project database, and published exposure data. These proportions were applied to Quebec labor force data. Among the 38 studied, carcinogens with the largest proportions of exposed workers were solar radiation (6.6% of workers), night shift work/rotating shift work including nights (6.0%), diesel exhaust fumes (4.4%), wood dust (2.9%) and polycyclic aromatic hydrocarbons (2.0%). More than 15 carcinogens were identified in several industrial sectors, and up to 100,000 young workers are employed in these sectors. Although crude, estimates obtained with different data sources allow identification of research and intervention priorities for cancer in Quebec. Copyright © 2013 Wiley Periodicals, Inc.

Risk for work-related fatigue among the employees on semiconductor manufacturing lines.

PubMed

Lin, Yu-Cheng; Chen, Yen-Cheng; Hsieh, Hui-I; Chen, Pau-Chung

2015-03-01

To examine the potential risk factors for work-related fatigue (WRF) among workers in modern industries, the authors analyzed the records of need-for-recovery questionnaires and health checkup results for 1545 employees. Compared with regular daytime workers, and after adjusting for confounders, the workers adapting to day-and-night rotating shift work (RSW) had a 4.0-fold (95% confidence interval [CI] = 2.7-5.9) increased risk for WRF, higher than the 2.2-fold risk (95% CI = 1.5-3.3) for persistent shift workers. Based on highest education level, the male employees with university degrees had the highest adjusted odds ratio (a-OR) 2.8 (95% CI = 1.0-7.8) for complaining of WRF versus compulsory education group. For female workers, currently married/cohabiting status was inversely associated with WRF (a-OR = 0.5; 95% CI = 0.2-0.9), and child-rearing responsibility moderately increased WRF risk (a-OR = 1.9; 95% CI = 1.0-3.7). Day-and-night RSW and the adaptation, educational levels of males, and domestic factors for females contributed to WRF among semiconductor manufacturing employees. © 2013 APJPH.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Longhouser, G.A. Jr.

Human beings are diurnal species, normally active by day and asleep by night. Yet over thirty million Americans struggle with work schedules that include an off-normal work effort. The railroads, law enforcement, health services, Department of Defense, factory workers, chemical plants and public services, communications and utility workers must provide some form of around-the-clock effort. Shift work has been around since the advent of recorded history. There has always been a need for some type of off-normal service and assistance. The impact of shift work is replete with tales and factual evidence of an increased personnel error rate; disorders, bothmore » personal and family, and of course, increased accident events. In recent memory, the Three Mile Island Nuclear Plant incident, Union Carbide`s explosion in Bhopal, and the Chernobyl Nuclear Plant catastrophe all occurred during off-normal working hours. Yet management overall has done little to correct the production-driven twelve hour, seven day week shift mentality of the nineteenth century. Most schedules in use today are nothing more than cosmetic variations of the old production schedules. This could be driven by a management consideration of the worker`s response to change coupled with a reluctant buy-in of responsibility for the effects of change. Florida Power Corporation has developed for its nuclear security force, a unique work schedule which attempts to employ the sound principles of circadian rhythms coupled with a comprehensive training program to counter the problems associated with shift work. The results over the last four years have seen a marked reduction in the generic problems of personnel errors, absenteeism, unscheduled overtime and turnover rates. Utilization and understanding of this scheduling process for rotational shift work needs to be assessed to determine if the benefits are site specific or provide an expected response to the problems of shift work.« less

Effects of fatigue on immune function in nurses performing shift work.

PubMed

Nagai, Makie; Morikawa, Yuko; Kitaoka, Kazuyo; Nakamura, Koshi; Sakurai, Masaru; Nishijo, Muneko; Hamazaki, Yuko; Maruzeni, Shoko; Nakagawa, Hideaki

2011-01-01

We investigated the effects of fatigue on NK cell function and lymphocyte subpopulations in nurses performing shift work using a longitudinal design. Fifty-seven female nurses engaged in shift work at a hospital in Japan were selected for our study cohort. The hospital used a counterclockwise rotating three-shift system. Night shifts followed day shifts after a seven-hour interval. Immune parameters measured at the beginning of the day shift through to the end of the night shift were compared between two groups stratified by their level of fatigue. Statistical differences were evaluated after adjusting for baseline immune values and other demographic features. Subjective feelings of fatigue increased progressively from the beginning of day shifts to the end of night shifts. From the beginning of day shifts to the end of night shifts, NK cell activity and CD16(+)CD56(+) lymphocytes decreased, while CD3(+) and CD4(+) lymphocytes increased. The group with the greater increase in fatigue showed a larger decrease in NK cell activity and a larger increase in CD4(+)lymphocytes when compared with the group reporting less fatigue. These findings did not change after adjusting for demographic factors and sleep hours. Our data suggest that shift work has deleterious effects on NK cell function and that the effects depend on the degree of fatigue. Proper management of shift work may lessen fatigue in workers and also ameliorate many health problems experienced by shift workers.

Shift work and age as interactive predictors of body mass index among offshore workers.

PubMed

Parkes, Katharine R

2002-02-01

This study investigated shift pattern (day shifts versus day-night rotation) and its interactions with age, and with years of shiftwork exposure, as predictors of body mass index (BMI). Survey data were collected from offshore personnel working day shifts (N=787) or day-night shifts (N=787); information was obtained about shift pattern and years of shiftwork exposure, height, weight, demographic factors, and smoking habits. Hierarchical multiple regression was used to test a model in which BMI was predicted by additive and interactive effects of shift pattern, age, and exposure years with control for confounding variables. In a multivariate analysis (controlling for job type, education and smoking), BMI was predicted by the main effects of age and years of shiftwork exposure. Shift pattern was not significant as a main effect, but it interacted significantly with the curvilinear age term and with the linear and curvilinear components of shiftwork exposure. In the day shift group, age but not exposure predicted BMI; the opposite was true of the day-night shift group. The increase in BMI with an increase in age and exposure years was steeper for the day-night shift group than for the day shift group. The significant interaction effects found in this study were consistent with the view that continued exposure to day-night shift work gives rise to increases in BMI, over and above the normative effects of ageing on BMI shown by day-shift workers.

Association of Rotating Night Shift Work with BMI and Abdominal Obesity among Nurses and Midwives.

PubMed

Peplonska, Beata; Bukowska, Agnieszka; Sobala, Wojciech

2015-01-01

Mounting epidemiological evidence suggests that night shift work may contribute to the etiology of increased body weight. The present study aimed to examine association between rotating night shift work and body mass index (BMI), and abdominal adiposity respectively among nurses and midwives. A cross-sectional study was conducted among 724 female nurses and midwives, aged 40-60 years (354 rotating night shift and 370 daytime workers) in Łódź, Poland, between 2008 and 2011. Information about occupational history and potential confounders was collected during personal interviews. Anthropometric measurements of body weight, height, waist (WC) and hip (HC) circumference were made, and body mass index (BMI), waist to hip ratio (WHR) and waist to height ratio (WHtR) were calculated. GLM regression models and multinomial logit regression models were fitted to explore the association between night shift work and anthropometric parameters, with adjustment for age, body silhouette at age 20, current smoking status, packyears, marital status, and menopausal hormone therapy use. Cumulative night shift work showed significant associations with BMI, WC, HC and WHtR, with BMI increasing by 0.477 kg/m2 per 1000 night duties and by 0.432 kg/m2 per 10000 night shift hours, WC increasing respectively by 1.089 cm and 0.99 cm, and HC by 0.72 cm and WHtR by 0.007 cm for both metrics. Both current and cumulative night work was associated with obesity (BMI≥30kg/m2), with OR=3.9 (95%CI:1.5-9.9), in women reporting eight or more night shifts per month. The results of the study support the previously reported relations between night shift work and development of obesity.

Association of Rotating Night Shift Work with BMI and Abdominal Obesity among Nurses and Midwives

PubMed Central

Peplonska, Beata; Bukowska, Agnieszka; Sobala, Wojciech

2015-01-01

Background Mounting epidemiological evidence suggests that night shift work may contribute to the etiology of increased body weight. The present study aimed to examine association between rotating night shift work and body mass index (BMI), and abdominal adiposity respectively among nurses and midwives. Methods A cross-sectional study was conducted among 724 female nurses and midwives, aged 40-60 years (354 rotating night shift and 370 daytime workers) in Łódź, Poland, between 2008 and 2011. Information about occupational history and potential confounders was collected during personal interviews. Anthropometric measurements of body weight, height, waist (WC) and hip (HC) circumference were made, and body mass index (BMI), waist to hip ratio (WHR) and waist to height ratio (WHtR) were calculated. GLM regression models and multinomial logit regression models were fitted to explore the association between night shift work and anthropometric parameters, with adjustment for age, body silhouette at age 20, current smoking status, packyears, marital status, and menopausal hormone therapy use. Results Cumulative night shift work showed significant associations with BMI, WC, HC and WHtR, with BMI increasing by 0.477 kg/m2 per 1000 night duties and by 0.432 kg/m2 per 10000 night shift hours, WC increasing respectively by 1.089 cm and 0.99 cm, and HC by 0.72 cm and WHtR by 0.007 cm for both metrics. Both current and cumulative night work was associated with obesity (BMI≥30kg/m2), with OR=3.9 (95%CI:1.5-9.9), in women reporting eight or more night shifts per month. Conclusion The results of the study support the previously reported relations between night shift work and development of obesity. PMID:26196859

Shift work and overall and cause-specific mortality in the Danish nurse cohort.

PubMed

Jørgensen, Jeanette Therming; Karlsen, Sashia; Stayner, Leslie; Andersen, Johnni; Andersen, Zorana Jovanovic

2017-03-01

Objectives Evidence of an effect of shift work on all-cause and cause-specific mortality is inconsistent. This study aims to examine whether shift work is associated with increased all-cause and cause-specific mortality. Methods We linked 28 731 female nurses (age ≥44 years), recruited in 1993 or 1999 from the Danish nurse cohort where they reported information on shift work (night, evening, rotating, or day), to the Danish Register of Causes of Death to identify deaths up to 2013. We used Cox regression models with age as the underlying scale to examine the associations between night, evening, and rotating shift work (compared to day shift work) and all-cause and cause-specific mortality in models adjusted for potentially confounding variables. Results Of 18 015 nurses included in this study, 1616 died during the study time period from the following causes: cardiovascular disease (N=217), cancer (N= 945), diabetes (N=20), Alzheimer's disease or dementia (N=33), and psychiatric diseases (N=67). We found that working night [hazard ratio (HR) 1.26, 95% confidence interval 95% CI) 1.05-1.51] or evening (HR 1.29, 95% CI 1.11-1.49) shifts was associated with a significant increase in all-cause mortality when compared to working day shift. We found a significant association of night shift work with cardiovascular disease (HR 1.71, 95% CI 1.09-2.69) and diabetes (HR 12.0, 95% CI 3.17-45.2, based on 8 cases) and none with overall cancer mortality (HR 1.05, 95% CI 0.81-1.35) or mortality from psychiatric diseases (HR 1.17, 95% CI 0.47-2.92). Finally, we found strong association between evening (HR 4.28, 95% CI 1.62-11.3) and rotating (HR 5.39, 95% CI 2.35-12.3) shift work and mortality from Alzheimer's disease and dementia (based on 8 and 14 deaths among evening and rotating shift workers, respectively). Conclusions Women working night and evening shifts have increased all-cause, cardiovascular, diabetes, and Alzheimer's and dementia mortality.

Work schedules and 11-year progression of carotid atherosclerosis in middle-aged Finnish men.

PubMed

Wang, Aolin; Arah, Onyebuchi A; Kauhanen, Jussi; Krause, Niklas

2015-01-01

This study investigated the relationship between different work schedules and progression of carotid atherosclerosis, an early indicator of cardiovascular disease (CVD). We studied 621 men, aged 42-60 years, in the prospective Kuopio Ischemic Heart Disease Risk Factor Study cohort. Using multivariable regressions adjusting for 22 covariates including total time worked during follow-up, we evaluated the associations of baseline work schedules with 11-year progression of ultrasonographically assessed carotid intima-media thickness (IMT), and their variation by preexisting CVD. Standard daytime work, weekend shifts, and evening/night/rotating shifts were associated with 31%, 37%, and 33% increases in IMT, respectively. Compared to daytime workers, weekend workers experienced a faster progression of carotid atherosclerosis [relative change ratio (RCR) = 1.05, 95% CI: 1.00-1.09)]. This ratio was higher among men who had preexisting CVD. Weekend shifts, more than standard daytime work, appear to accelerate carotid atherosclerosis progression among middle-aged Finnish men, especially those with pre-existing CVD. © 2014 Wiley Periodicals, Inc.

Work-leave rotation pattern and incidence of offshore workplace injury.

PubMed

Massey, S

2018-05-17

Studies on work-leave rotation pattern and work place injuries among offshore oil and gas workers have been few and limited to a 2- or 3-week rotation schedule. To examine incidence of workplace injury in relation to the duration of time into work rotation for extended work schedules up to 24 weeks. Six-year injury data on four offshore installations were extracted. Data were analysed for incidence of injury over time and relative risk using linear trend lines and regression. In total, 311 injuries for 1302 workers were analysed, 39% with rotation schedule of 4 weeks work and 4 weeks rest, 27% 8 weeks work and 4 weeks rest, 23% 16 weeks work and 4 weeks rest and 10% 24 weeks work and 4 weeks rest. Incidence of injury decreased as duration of time into the work rotation increased, corrected for exposure, and this was statistically significant for all rotations in first 4 weeks (P < 0.01). Negative correlation between time offshore and injury was observed in all schedules and consistent for age groups, categories of work, shifts and severity of injury. There was no difference in relative risk of injuries between the four schedules, when corrected for exposure and occupational risk of injury. These results are at variance with previous studies, although no prior study has looked beyond 3-week rotation schedule. Longer offshore schedules are safely possible and this could help decrease manpower and logistics costs for oil and gas companies coping with unprecedented low oil prices.

Validation of a Questionnaire to Screen for Shift Work Disorder

PubMed Central

Barger, Laura K.; Ogeil, Rowan P.; Drake, Christopher L.; O'Brien, Conor S.; Ng, Kim T.; Rajaratnam, Shantha M. W.

2012-01-01

Study Objective: At least 15% of the full-time work force is shift workers. Working during the overnight hours, early morning start times, and variable or rotating schedules present a challenge to the circadian system, and these shifts are associated with adverse health and safety consequences. Shift work disorder (SWD), a primary (circadian rhythm) sleep disorder indicated by excessive daytime sleepiness and/or insomnia associated with a shiftwork schedule, is under-recognized by primary care physicians. We sought to develop and validate a questionnaire to screen for high risk of SWD in a shift working population. Design: Shift workers completed a 26-item questionnaire and were evaluated by a sleep specialist (physician) who diagnosed them as either positive or negative for SWD. The physician assessment of SWD was guided by a flow chart that operationalized the ICSD-2 criteria for SWD. Setting: 18 sleep clinics in the USA. Patients or Participants: 311 shift workers. Interventions: Not applicable. Measurements and Results: Responses to the items in the questionnaire were entered into a series of discrimination function analyses to determine the diagnostic value of the items and the fewest number of questions with the best predictive value. The function was then cross-validated. A final 4-item questionnaire has 89% positive predictive value and 62% negative predictive value (sensitivity = 0.74; specificity = 0.82). Conclusions: This Shiftwork Disorder Screening Questionnaire may be appropriate for use in primary care settings to aid in the diagnosis of SWD. Citation: Barger LK; Ogeil RP; Drake CL; O'Brien CS; Ng KT; Rajaratnam SMW. Validation of a questionnaire to screen for shift work disorder. SLEEP 2012;35(12):1693–1703. PMID:23204612

Shift work and hypertension: Prevalence and analysis of disease pathways in a German car manufacturing company.

PubMed

Ohlander, Johan; Keskin, Mekail-Cem; Stork, Joachim; Radon, Katja

2015-05-01

Hypertension and cardiovascular disease (CVD) may share a similar pathophysiology. Despite shift workers' CVD excess risk, studies on shift work and hypertension are inconclusive. Blood pressure and shift status for 25,343 autoworkers were obtained from medical check-ups and company registers. Cross-sectional associations modeling the total effect from shift work (day shifts, shift work without nights, rotating shift work with nights, and night shifts) on hypertension were assessed. By sequential adjustments, the influence of behavioral, psychosocial, and physiological factors on the total effect was examined, with subsequent mediation and moderation analyses. Adjusted for confounders, shift work without nights (vs. day shifts) was significantly associated with hypertension (OR 1.15, 95%CI 1.02-1.30). The total effect was mediated by BMI, physical inactivity, and sleep disorders. No moderation of the total effect by behaviors was found. The association between shift work and hypertension seems mainly attributable to behavioral mechanisms. © 2015 Wiley Periodicals, Inc.

The Cumulative Lifting Index (CULI) for the Revised NIOSH Lifting Equation: Quantifying Risk for Workers With Job Rotation.

PubMed

Garg, Arun; Kapellusch, Jay M

2016-08-01

The objectives were to: (a) develop a continuous frequency multiplier (FM) for the Revised NIOSH Lifting Equation (RNLE) as a function of lifting frequency and duration of a lifting task, and (b) describe the Cumulative Lifting Index (CULI), a methodology for estimating physical exposure to workers with job rotation. The existing FM for the RNLE (FME) does not differentiate between task duration >2 hr and <8 hr, which makes quantifying physical exposure to workers with job rotation difficult and presents challenges to job designers. Using the existing FMs for 1, 2, and 8 hr of task durations, we developed a continuous FM (FMP) that extends to 12 hr per day. We simulated 157,500 jobs consisting of two tasks each and, using different combinations of Frequency Independent Lifting Index, lifting frequency and duration of lifting. Biomechanical stresses were estimated using the CULI, time-weighted average (TWA), and peak exposure. The median difference between FME and FMP was ±1% (range: 0%-15%). Compared to CULI, TWA underestimated risk of low-back pain (LBP) for 18% to 30% of jobs, and peak exposure for an assumed 8-hr work shift overestimated risk of LBP for 20% to 25% of jobs. Peak task exposure showed 90% agreement with CULI but ignored one of two tasks. The CULI partially addressed the underestimation of physical exposure using the TWA approach and overestimation of exposure using the peak-exposure approach. The proposed FM and CULI may provide more accurate physical exposure estimates, and therefore estimated risk of LBP, for workers with job rotation. © 2016, Human Factors and Ergonomics Society.

VALIDITATION OF A LIGHT QUESTIONNAIRE WITH REAL-LIFE PHOTOPIC ILLUMINANCE MEASUREMENTS: THE HARVARD LIGHT EXPOSURE ASSESSMENT QUESTIONNAIRE

PubMed Central

Bajaj, Archna; Rosner, Bernard; Lockley, Steven; Schernhammer, Eva S.

2011-01-01

Background Light exposure at night is now considered a probable carcinogen. To study the effects of light on chronic diseases like cancer, methods to measure light exposure in large observational studies are needed. We aimed to investigate the validity of self-reported current light exposure. Methods We developed a self-administered semiquantitative light questionnaire, the Harvard Light Exposure Assessment (H-LEA) questionnaire, and compared photopic scores derived from this questionnaire with actual photopic and circadian measures obtained from a real-life 7-day light meter application among 132 women (85 rotating night shift workers and 47 day workers) participating in the Nurses' Health Study II. Results After adjustment for age, BMI, collection day, and night work status, the overall partial Spearman correlation between self-report of light exposure and actual photopic light measurements was 0.72 (P<0.001; Kendall τ =0.57) and 0.73 (P<0.0001; Kendall τ =0.58) when correlating circadian light measurements. There were only minimal differences in accuracy of self-report of light exposure and photopic or circadian light measurement between day (r=0.77 and 0.78, respectively) and rotating night shift workers (r=0.68 and 0.69, respectively). Conclusions The results of this study provide evidence of the criterion validity of self-reported light exposure using the H-LEA questionnaire. Impact: This questionnaire is a practical method of assessing light exposure in large scale epidemiologic studies. PMID:21737411

Body mass index and factors related to overweight among women workers in electronic factories in Peninsular Malaysia.

PubMed

Chee, Heng-Leng; Kandiah, Mirnalini; Khalid, Maimunah; Shamsuddin, Khadijah; Jamaluddin, Jamilah; Nordin, Nor Anita Megat Mohd; Shuib, Rashidah; Osman, Intan

2004-01-01

Factors related to overweight were examined in a cross-sectional survey that included 1612 women workers from 10 large electronics assembly factories in Peninsular Malaysia. Respondents were Malaysian citizens, direct production workers below the supervisory level, and had worked at least a year in the factory where they were presently employed. Heights and weights were taken to calculate the body mass index (BMI). Weights and BMI increased with increasing age. After adjusting for age, odds ratios for overweight were significantly raised for married women in relation to not married women (OR 1.5, 95% CI=1.15-2.02), lower secondary education in relation to higher than upper secondary education (OR 1.8, 95% CI=1.06-3.14), monthly income RM800-999 (OR 1.7, 95% CI=1.21-2.45) and >/=RM1,000 (OR 1.8, 95% CI=1.23-2.72) in relation to

Factors affecting work ability in day and shift-working nurses.

PubMed

Camerino, Donatella; Conway, Paul Maurice; Sartori, Samantha; Campanini, Paolo; Estryn-Béhar, Madeleine; van der Heijden, Beatrice Isabella Johanna Maria; Costa, Giovanni

2008-04-01

Satisfactory work ability is sustained and promoted by good physical and mental health and by favorable working conditions. This study examined whether favorable and rewarding work-related factors increased the work ability among European nurses. The study sample was drawn from the Nurses' Early Exit Study and consisted of 7,516 nursing staff from seven European countries working in state-owned and private hospitals. In all, 10.8% were day, 4.2% were permanent night, 20.9% were shift without night shift, and 64.1% were shift workers with night shifts. Participants were administered a composite questionnaire at baseline (Time 0) and 1 yr later (Time 1). The Work Ability Index (WAI) at Time 1 was used as the outcome measure, while work schedule, sleep, rewards (esteem and career), satisfaction with pay, work involvement and motivation, and satisfaction with working hours at Time 0 were included as potential determinants of work ability. Univariate and multivariate analyses were conducted after adjusting for a number of confounders (i.e., country, age, sex, type of employment, family status, and other job opportunities in the same area). Work schedule was not related to Time 1 changes in WAI. Higher sleep quality and quantity and more favorable psychosocial factors significantly increased work ability levels. Higher sleep quality and quantity did not mediate the effect of work schedule on work ability. No relevant interaction effects on work ability were observed between work schedule and the other factors considered at Time 0. As a whole, sleep and satisfaction with working time were gradually reduced from day work to permanent night work. However, scores on work involvement, motivation, and satisfaction with pay and rewards were the highest in permanent night workers and the lowest in rotating shift workers that included night shifts.

Is health, measured by work ability index, affected by 12-hour rotating shift schedules?

PubMed

Yong, Mei; Nasterlack, Michael; Pluto, Rolf-Peter; Elmerich, Kathrin; Karl, Dorothee; Knauth, Peter

2010-07-01

Two forms of continuously forward rotating 12-h shift schedules exist at BASF's Ludwigshafen site. These shift schedules were compared with a daytime working system to investigate potential differential effects on employee's health status assessed with the Work Ability Index (WAI). In the 3 x 12 system, a 12-h day shift is followed 24 h later by a 12-h night shift, and after a day off the employee returns to the day shift. The 4 x 12 schedule follows the same pattern except that there are 2 days off between the night and next day shift. A total of 924 participants (278 3 x 12 and 321 4 x 12 shiftworkers and 325 day workers) were recruited. A self-administered questionnaire was used to obtain information about shiftwork schedule, demographic characteristics, and lifestyle and social factors, and the WAI was applied. The outcomes of interest were the WAI sum score and its seven dimensions. In examining the relationship with the WAI categories, a Proportional Odds Model (POM) was used to identify the potential determinants. Logistic regression models were used to estimate the impact of age on single dimensions of WAI after adjustment for potential confounding factors. Increasing age and obesity (BMI > or = 30) were the only significant determinants of poorer WAI. Although a positive association was found linking the second WAI dimension (work ability in relation to job demands) with age, an inverse association was demonstrated consistently between age and the third and fourth WAI dimensions, i.e., number of diagnosed diseases and estimated work impairment due to disease, after adjustment for potential confounders. The age-dependency was moderate overall, but seemed to be stronger among shift- than day workers, although this difference did not reach statistical significance. There was no significant differential impact of the working time systems on the WAI sum score or on the individual WAI dimensions. Thus, there is no indication of an excessive adverse health impact of these shift schedules compared to day work, to the extent that health can be measured by the WAI.

Does night-shift work induce apnea events in obstructive sleep apnea patients?

PubMed

Laudencka, A; Klawe, J J; Tafil-Klawe, M; Złomańczuk, P

2007-11-01

The aim of the present study was to determine the direct effect of night-work on the occurrence of obstructive apneas during sleep after a night shift in fast-rotating shift workers with sleep-related breathing disorders. Eight obstructive sleep apnea patients were examined with the use of a polysomnograph during sleep under two conditions: after day-shift work and after night-shift work. Both sleep studies were conducted within 2 to 3 weeks of each other. In four of the 8 subjects, during sleep after a night-shift, an increase in apnea/hypopnea index was found. Night work significantly increased several breathing variables: total duration of obstructive apneas during REM sleep, mean duration of obstructive apneas during arousal, and apnea index during arousal. We conclude that in a subpopulation of sleep apnea patients, acute sleep deprivation may worsen obstructive sleep apnea index.

Breast cancer risk and night shift work in a case-control study in a Spanish population.

PubMed

Papantoniou, Kyriaki; Castaño-Vinyals, Gemma; Espinosa, Ana; Aragonés, Nuria; Pérez-Gómez, Beatriz; Ardanaz, Eva; Altzibar, Jone Miren; Sanchez, Vicente Martin; Gómez-Acebo, Inés; Llorca, Javier; Muñoz, David; Tardón, Adonina; Peiró, Rosana; Marcos-Gragera, Rafael; Pollan, Marina; Kogevinas, Manolis

2016-09-01

Epidemiologic and animal data indicate that night shift work might increase the risk for breast cancer. We evaluated the association of night work with different clinical types of breast cancer in a population based case-control study (MCC-Spain study) taking into account chronotype, an individual characteristic that may relate to night shift work adaptation. Lifetime occupational history was assessed by face-to-face interviews and shift work information was available for 1708 breast cancer cases and 1778 population controls from 10 Spanish regions, enrolled from 2008 to 2013. We evaluated three shift work domains, including shift work type (permanent vs rotating), lifetime cumulative duration and frequency. We estimated odds ratios (OR) for night work compared to day work using unconditional logistic regression models adjusting for confounders. Having ever worked permanent or rotating night shift was associated with an increased risk for breast cancer compared to day workers [odds ratio (OR) 1.18; 95 % CI 0.97, 1.43]. Chronotype was differentially associated with breast cancer depending on the duration of night shift work. Risk was higher in women with invasive tumors (OR 1.23; 95 % CI 1.00, 1.51) and for estrogen and progestagen positive tumors among premenopausal women (OR 1.44; 95 % CI 1.05, 1.99). Having ever performed night shift was associated with a small increased risk for breast cancer and especially in subgroups of women with particular hormone related characteristics.

Actigraph measures of sleep among female hospital employees working day or alternating day and night shifts.

PubMed

Korsiak, Jill; Tranmer, Joan; Leung, Michael; Borghese, Michael M; Aronson, Kristan J

2017-07-14

Sleep disturbance is common among shift workers, and may be an important factor in the effect of shift work on chronic disease development. In this cross-sectional study, we described sleep patterns of 294 female hospital workers (142 alternating day-night shift workers, 152 day workers) and determined associations between shift work and sleep duration. Rest-activity cycles were recorded with the ActiGraph GT3X+ for 1 week. Analyses were stratified by chronotype of shift workers. Using all study days to calculate average sleep duration, shift workers slept approximately 13 min less than day workers during main sleep periods, while 24-h sleep duration did not differ between day workers and shift workers. Results from age-adjusted models demonstrated that all shift workers, regardless of chronotype, slept 20-30 min less than day workers on day shifts during main and total sleep. Early and intermediate chronotypes working night shifts slept between 114 and 125 min less than day workers, both with regard to the main sleep episode and 24-h sleep duration, while the difference was less pronounced among late chronotypes. When sleep duration on free days was compared between shift workers and day workers, only shift workers with late chronotypes slept less, by approximately 50 min, than day workers during main sleep. Results from this study demonstrate how an alternating day-night shift work schedule impacts sleep negatively among female hospital workers, and the importance of considering chronotype in sleep research among shift workers. © 2017 European Sleep Research Society.

Rotating Night Shift Work and Risk of Type 2 Diabetes: Two Prospective Cohort Studies in Women

PubMed Central

Pan, An; Schernhammer, Eva S.; Sun, Qi; Hu, Frank B.

2011-01-01

Background Rotating night shift work disrupts circadian rhythms and has been associated with obesity, metabolic syndrome, and glucose dysregulation. However, its association with type 2 diabetes remains unclear. Therefore, we aimed to evaluate this association in two cohorts of US women. Methods and Findings We followed 69,269 women aged 42–67 in Nurses' Health Study I (NHS I, 1988–2008), and 107,915 women aged 25–42 in NHS II (1989–2007) without diabetes, cardiovascular disease, and cancer at baseline. Participants were asked how long they had worked rotating night shifts (defined as at least three nights/month in addition to days and evenings in that month) at baseline. This information was updated every 2–4 years in NHS II. Self-reported type 2 diabetes was confirmed by a validated supplementary questionnaire. We documented 6,165 (NHS I) and 3,961 (NHS II) incident type 2 diabetes cases during the 18–20 years of follow-up. In the Cox proportional models adjusted for diabetes risk factors, duration of shift work was monotonically associated with an increased risk of type 2 diabetes in both cohorts. Compared with women who reported no shift work, the pooled hazard ratios (95% confidence intervals) for participants with 1–2, 3–9, 10–19, and ≥20 years of shift work were 1.05 (1.00–1.11), 1.20 (1.14–1.26), 1.40 (1.30–1.51), and 1.58 (1.43–1.74, p-value for trend <0.001), respectively. Further adjustment for updated body mass index attenuated the association, and the pooled hazard ratios were 1.03 (0.98–1.08), 1.06 (1.01–1.11), 1.10 (1.02–1.18), and 1.24 (1.13–1.37, p-value for trend <0.001). Conclusions Our results suggest that an extended period of rotating night shift work is associated with a modestly increased risk of type 2 diabetes in women, which appears to be partly mediated through body weight. Proper screening and intervention strategies in rotating night shift workers are needed for prevention of diabetes. Please see later in the article for the Editors' Summary PMID:22162955

Conflict between work and family roles and satisfaction among nurses in different shift systems in Croatia: a questionnaire survey.

PubMed

Simunić, Ana; Gregov, Ljiljana

2012-06-01

The objective of this study was to examine the perception of conflict between work and family roles and job, family, and life satisfaction among nurses in Croatia. One hundred and twenty-nine nurses (married mothers) working in hospitals in Zadar, Šibenik, and Split were divided in four groups according to their worktime schedule. The participants completed a survey, which included a set of sociodemographic-type questions, questions about the level and allocation of family responsibilities between spouses, and scales measuring the perceived negative effects of worktime, psychological demands of the work, work-family conflict, and semantic differential scales for measuring the affective and cognitive-evaluative component of job, family, and life satisfaction. This was the first study in Croatia to deal with work-family conflict among nurses or workers with different shift systems.The results of this study indicate that nurses working morning shifts only experienced less conflict between work and family than other groups of nurses, who worked the morning, afternoon, and the night shift. The cognitive-evaluative component of job satisfaction was the highest among morning shift nurses and the lowest in nurses who worked 12-hour shifts, while the affective component of life satisfaction was the lowest in nurses working irregular and backward rotated shifts. These results confirm that shiftwork makes the work-family role conflict even worse. They also support the view that the type of shift rotation matters.

Influence of shift work on the physical work capacity of Tunisian nurses: a cross-sectional study in two university hospitals.

PubMed

Merchaoui, Irtyah; Bouzgarrou, Lamia; Mnasri, Ahlem; Mghanem, Mounir; Akrout, Mohamed; Malchaire, Jacques; Chaari, Neila

2017-01-01

This study has been performed to determine the influence of rotating shift work on physical working capacity of Tunisian nurses and to design recommendations to managers so that they implement effective preventive measures. It is a cross-sectional design using a standardized questionnaire and many physical capacity tests on a representative sample of 1181 nurses and nursing assistants from two university hospital centers of the school of Medicine of Monastir located in the Tunisian Sahel. 293 participants have been recruited by stratified random sampling according to gender and departments. Maximum Grip strength, 30s sit-to-stand test, one leg test, Fingertip-to-Floor test, Saltsa test and peak expiratory flow were used to assess physical capacity. Work ability was assessed through the workability index. Mental and physical loads were heavily perceived in shift healthcare workers (p=0.01; p=0.02). The maximum grip force was stronger in rotating shift work nurses (p=0.0001). Regarding to the seniority subgroups in each kind of work schedule, the Body Mass Index was increasing with seniority in both schedules. All the physical tests, were better in less-than-ten-year groups. Peak Flow and grip strength were significantly better in less-than-ten-year seniority in shift work group. There is a need to improve the design of the existing shift systems and to reduce as much as possible shift schedule as well as to avoid shift schedule for over-10-year-seniority nurses.

Effects of Filtering Visual Short Wavelengths During Nocturnal Shiftwork on Sleep and Performance

PubMed Central

Rahman, Shadab A.; Shapiro, Colin M.; Wang, Flora; Ainlay, Hailey; Kazmi, Syeda; Brown, Theodore J.

2013-01-01

Circadian phase resetting is sensitive to visual short wavelengths (450–480 nm). Selectively filtering this range of wavelengths may reduce circadian misalignment and sleep impairment during irregular light-dark schedules associated with shiftwork. We examined the effects of filtering short wavelengths (<480 nm) during night shifts on sleep and performance in nine nurses (five females and four males; mean age ± SD: 31.3 ± 4.6 yrs). Participants were randomized to receive filtered light (intervention) or standard indoor light (baseline) on night shifts. Nighttime sleep after two night shifts and daytime sleep in between two night shifts was assessed by polysomnography (PSG). In addition, salivary melatonin levels and alertness were assessed every 2 h on the first night shift of each study period and on the middle night of a run of three night shifts in each study period. Sleep and performance under baseline and intervention conditions were compared with daytime performance on the seventh day shift, and nighttime sleep following the seventh daytime shift (comparator). On the baseline night PSG, total sleep time (TST) (p < 0.01) and sleep efficiency (p = 0.01) were significantly decreased and intervening wake times (wake after sleep onset [WASO]) (p = 0.04) were significantly increased in relation to the comparator night sleep. In contrast, under intervention, TST was increased by a mean of 40 min compared with baseline, WASO was reduced and sleep efficiency was increased to levels similar to the comparator night. Daytime sleep was significantly impaired under both baseline and intervention conditions. Salivary melatonin levels were significantly higher on the first (p < 0.05) and middle (p < 0.01) night shifts under intervention compared with baseline. Subjective sleepiness increased throughout the night under both conditions (p < 0.01). However, reaction time and throughput on vigilance tests were similar to daytime performance under intervention but impaired under baseline on the first night shift. By the middle night shift, the difference in performance was no longer significant between day shift and either of the two night shift conditions, suggesting some adaptation to the night shift had occurred under baseline conditions. These results suggest that both daytime and nighttime sleep are adversely affected in rotating-shift workers and that filtering short wavelengths may be an approach to reduce sleep disruption and improve performance in rotating-shift workers. (Author correspondence: casper@lunenfeld.ca) PMID:23834705

SHIFT WORK AND BREAST CANCER AMONG WOMEN TEXTILE WORKERS IN SHANGHAI, CHINA

PubMed Central

Li, Wenjin; Ray, Roberta M.; Thomas, David B.; Davis, Scott; Yost, Michael; Breslow, Norman; Gao, Dao Li; Fitzgibbons, E. Dawn; Camp, Janice E.; Wong, Eva; Wernli, Karen J.; Checkoway, Harvey

2014-01-01

PURPOSE Although night shift work has been associated with elevated risk of breast cancer in numerous epidemiologic studies, evidence is not consistent. We conducted a nested case-cohort study to investigate a possible association between shift work including a night shift and risk of breast cancer within a large cohort of women textile workers in Shanghai, China. METHODS The study included 1709 incident breast cancer cases and 4780 non-cases. Data on historical shift-work schedules were collected by categorized jobs from the factories where the study subjects had worked, and then were linked to the complete work histories of each subject. No jobs in the factories involved exclusively night shift work. Therefore, night shift was evaluated as part of a rotating shift work pattern. Hazard ratios and 95% confidence intervals were calculated using Cox proportional hazards modeling adapted for the case-cohort design for years of night-shift work and the total number of nights worked. Additionally, analyses were repeated with exposures lagged by 10 and 20 years. RESULTS We observed no associations with either years of night-shift work, or number of nights worked during the entire employment period, irrespective of lag intervals. Findings from the age-stratified analyses were very similar to those observed for the entire study population. CONCLUSIONS The findings from this study provide no evidence to support the hypothesis that shift work increases breast cancer risk. The positive association between shift work and breast cancer observed in Western populations, but not observed in this and other studies of the Chinese population, suggest that the effect of shift work on breast cancer risk may be different in Asian and Caucasian women. PMID:25421377

Shift work and breast cancer among women textile workers in Shanghai, China.

PubMed

Li, Wenjin; Ray, Roberta M; Thomas, David B; Davis, Scott; Yost, Michael; Breslow, Norman; Gao, Dao Li; Fitzgibbons, E Dawn; Camp, Janice E; Wong, Eva; Wernli, Karen J; Checkoway, Harvey

2015-01-01

Although night-shift work has been associated with elevated risk of breast cancer in numerous epidemiologic studies, evidence is not consistent. We conducted a nested case-cohort study to investigate a possible association between shift work including a night shift and risk of breast cancer within a large cohort of women textile workers in Shanghai, China. The study included 1,709 incident breast cancer cases and 4,780 non-cases. Data on historical shift work schedules were collected by categorized jobs from the factories, where the study subjects had worked, and then were linked to the complete work histories of each subject. No jobs in the factories involved exclusively night-shift work. Therefore, night shift was evaluated as part of a rotating shift work pattern. Hazard ratios and 95 % confidence intervals were calculated using Cox proportional hazards modeling adapted for the case-cohort design for years of night-shift work and the total number of nights worked. Additionally, analyses were repeated with exposures lagged by 10 and 20 years. We observed no associations with either years of night-shift work or number of nights worked during the entire employment period, irrespective of lag intervals. Findings from the age-stratified analyses were very similar to those observed for the entire study population. The findings from this study provide no evidence to support the hypothesis that shift work increases breast cancer risk. The positive association between shift work and breast cancer observed in Western populations, but not observed in this and other studies of the Chinese population, suggests that the effect of shift work on breast cancer risk may be different in Asian and Caucasian women.

A unique, fast-forwards rotating schedule with 12-h long shifts prevents chronic sleep debt.

PubMed

Fischer, Dorothee; Vetter, Céline; Oberlinner, Christoph; Wegener, Sven; Roenneberg, Till

2016-01-01

Sleep debt--together with circadian misalignment--is considered a central factor for adverse health outcomes associated with shift work. Here, we describe in detail sleep-wake behavior in a fast-forward rotating 12-h shift schedule, which involves at least 24 hours off after each shift and thus allows examining the role of immediate recovery after shift-specific sleep debt. Thirty-five participants at two chemical plants in Germany were chronotyped using the Munich ChronoType Questionnaire for Shift-Workers (MCTQ(Shift)) and wore actimeters throughout the two-week study period. From these actimetry recordings, we computed sleep and nap duration, social jetlag (a measure of circadian misalignment), and the daily timing of activity and sleep (center of gravity and mid-sleep, respectively). We observed that the long off-work periods between each shift create a fast alternation between shortened (mean ± standard deviation, 5h 17min ± 56min) and extended (8h 25min ± 72min) sleep episodes resulting in immanent reductions of sleep debt. Additionally, extensive napping of early chronotypes (up to 3 hours before the night shift) statistically compensated short sleep durations after the night shift. Partial rank correlations showed chronotype-dependent patterns of sleep and activity that were similar to those previously described in 8-h schedules; however, sleep before the day shift did not differ between chronotypes. Our findings indicate that schedules preventing a build-up of chronic sleep debt may reduce detrimental effects of shift work irrespective of shift duration. Prospective studies are needed to further elucidate the relationship between sleep, the circadian system, and health and safety hazards.

Non-occupational physical activity levels of shift workers compared with non-shift workers

PubMed Central

Loef, Bette; Hulsegge, Gerben; Wendel-Vos, G C Wanda; Verschuren, W M Monique; Bakker, Marije F; van der Beek, Allard J; Proper, Karin I

2017-01-01

Objectives Lack of physical activity (PA) has been hypothesised as an underlying mechanism in the adverse health effects of shift work. Therefore, our aim was to compare non-occupational PA levels between shift workers and non-shift workers. Furthermore, exposure–response relationships for frequency of night shifts and years of shift work regarding non-occupational PA levels were studied. Methods Data of 5980 non-shift workers and 532 shift workers from the European Prospective Investigation into Cancer and Nutrition-Netherlands (EPIC-NL) were used in these cross-sectional analyses. Time spent (hours/week) in different PA types (walking/cycling/exercise/chores) and intensities (moderate/vigorous) were calculated based on self-reported PA. Furthermore, sports were operationalised as: playing sports (no/yes), individual versus non-individual sports, and non-vigorous-intensity versus vigorous-intensity sports. PA levels were compared between shift workers and non-shift workers using Generalized Estimating Equations and logistic regression. Results Shift workers reported spending more time walking than non-shift workers (B=2.3 (95% CI 1.2 to 3.4)), but shift work was not associated with other PA types and any of the sports activities. Shift workers who worked 1–4 night shifts/month (B=2.4 (95% CI 0.6 to 4.3)) and ≥5 night shifts/month (B=3.7 (95% CI 1.8 to 5.6)) spent more time walking than non-shift workers. No exposure–response relationships were found between years of shift work and PA levels. Conclusions Shift workers spent more time walking than non-shift workers, but we observed no differences in other non-occupational PA levels. To better understand if and how PA plays a role in the negative health consequences of shift work, our findings need to be confirmed in future studies. PMID:27872151

Non-occupational physical activity levels of shift workers compared with non-shift workers.

PubMed

Loef, Bette; Hulsegge, Gerben; Wendel-Vos, G C Wanda; Verschuren, W M Monique; Vermeulen, Roel C H; Bakker, Marije F; van der Beek, Allard J; Proper, Karin I

2017-05-01

Lack of physical activity (PA) has been hypothesised as an underlying mechanism in the adverse health effects of shift work. Therefore, our aim was to compare non-occupational PA levels between shift workers and non-shift workers. Furthermore, exposure-response relationships for frequency of night shifts and years of shift work regarding non-occupational PA levels were studied. Data of 5980 non-shift workers and 532 shift workers from the European Prospective Investigation into Cancer and Nutrition-Netherlands (EPIC-NL) were used in these cross-sectional analyses. Time spent (hours/week) in different PA types (walking/cycling/exercise/chores) and intensities (moderate/vigorous) were calculated based on self-reported PA. Furthermore, sports were operationalised as: playing sports (no/yes), individual versus non-individual sports, and non-vigorous-intensity versus vigorous-intensity sports. PA levels were compared between shift workers and non-shift workers using Generalized Estimating Equations and logistic regression. Shift workers reported spending more time walking than non-shift workers (B=2.3 (95% CI 1.2 to 3.4)), but shift work was not associated with other PA types and any of the sports activities. Shift workers who worked 1-4 night shifts/month (B=2.4 (95% CI 0.6 to 4.3)) and ≥5 night shifts/month (B=3.7 (95% CI 1.8 to 5.6)) spent more time walking than non-shift workers. No exposure-response relationships were found between years of shift work and PA levels. Shift workers spent more time walking than non-shift workers, but we observed no differences in other non-occupational PA levels. To better understand if and how PA plays a role in the negative health consequences of shift work, our findings need to be confirmed in future studies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

High risk of near-crash driving events following night-shift work

PubMed Central

Lee, Michael L.; Howard, Mark E.; Horrey, William J.; Liang, Yulan; Anderson, Clare; Shreeve, Michael S.; O’Brien, Conor S.; Czeisler, Charles A.

2016-01-01

Night-shift workers are at high risk of drowsiness-related motor vehicle crashes as a result of circadian disruption and sleep restriction. However, the impact of actual night-shift work on measures of drowsiness and driving performance while operating a real motor vehicle remains unknown. Sixteen night-shift workers completed two 2-h daytime driving sessions on a closed driving track at the Liberty Mutual Research Institute for Safety: (i) a postsleep baseline driving session after an average of 7.6 ± 2.4 h sleep the previous night with no night-shift work, and (ii) a postnight-shift driving session following night-shift work. Physiological measures of drowsiness were collected, including infrared reflectance oculography, electroencephalography, and electrooculography. Driving performance measures included lane excursions, near-crash events, and drives terminated because of failure to maintain control of the vehicle. Eleven near-crashes occurred in 6 of 16 postnight-shift drives (37.5%), and 7 of 16 postnight-shift drives (43.8%) were terminated early for safety reasons, compared with zero near-crashes or early drive terminations during 16 postsleep drives (Fishers exact: P = 0.0088 and P = 0.0034, respectively). Participants had a significantly higher rate of lane excursions, average Johns Drowsiness Scale, blink duration, and number of slow eye movements during postnight-shift drives compared with postsleep drives (3.09/min vs. 1.49/min; 1.71 vs. 0.97; 125 ms vs. 100 ms; 35.8 vs. 19.1; respectively, P < 0.05 for all). Night-shift work increases driver drowsiness, degrading driving performance and increasing the risk of near-crash drive events. With more than 9.5 million Americans working overnight or rotating shifts and one-third of United States commutes exceeding 30 min, these results have implications for traffic and occupational safety. PMID:26699470

High risk of near-crash driving events following night-shift work.

PubMed

Lee, Michael L; Howard, Mark E; Horrey, William J; Liang, Yulan; Anderson, Clare; Shreeve, Michael S; O'Brien, Conor S; Czeisler, Charles A

2016-01-05

Night-shift workers are at high risk of drowsiness-related motor vehicle crashes as a result of circadian disruption and sleep restriction. However, the impact of actual night-shift work on measures of drowsiness and driving performance while operating a real motor vehicle remains unknown. Sixteen night-shift workers completed two 2-h daytime driving sessions on a closed driving track at the Liberty Mutual Research Institute for Safety: (i) a postsleep baseline driving session after an average of 7.6 ± 2.4 h sleep the previous night with no night-shift work, and (ii) a postnight-shift driving session following night-shift work. Physiological measures of drowsiness were collected, including infrared reflectance oculography, electroencephalography, and electrooculography. Driving performance measures included lane excursions, near-crash events, and drives terminated because of failure to maintain control of the vehicle. Eleven near-crashes occurred in 6 of 16 postnight-shift drives (37.5%), and 7 of 16 postnight-shift drives (43.8%) were terminated early for safety reasons, compared with zero near-crashes or early drive terminations during 16 postsleep drives (Fishers exact: P = 0.0088 and P = 0.0034, respectively). Participants had a significantly higher rate of lane excursions, average Johns Drowsiness Scale, blink duration, and number of slow eye movements during postnight-shift drives compared with postsleep drives (3.09/min vs. 1.49/min; 1.71 vs. 0.97; 125 ms vs. 100 ms; 35.8 vs. 19.1; respectively, P < 0.05 for all). Night-shift work increases driver drowsiness, degrading driving performance and increasing the risk of near-crash drive events. With more than 9.5 million Americans working overnight or rotating shifts and one-third of United States commutes exceeding 30 min, these results have implications for traffic and occupational safety.

Light at Night and Measures of Alertness and Performance: Implications for Shift Workers.

PubMed

Figueiro, Mariana G; Sahin, Levent; Wood, Brittany; Plitnick, Barbara

2016-01-01

Rotating-shift workers, particularly those working at night, are likely to experience sleepiness, decreased productivity, and impaired safety while on the job. Light at night has been shown to have acute alerting effects, reduce sleepiness, and improve performance. However, light at night can also suppress melatonin and induce circadian disruption, both of which have been linked to increased health risks. Previous studies have shown that long-wavelength (red) light exposure increases objective and subjective measures of alertness at night, without suppressing nocturnal melatonin. This study investigated whether exposure to red light at night would not only increase measures of alertness but also improve performance. It was hypothesized that exposure to both red (630 nm) and white (2,568 K) lights would improve performance but that only white light would significantly affect melatonin levels. Seventeen individuals participated in a 3-week, within-subjects, nighttime laboratory study. Compared to remaining in dim light, participants had significantly faster reaction times in the GO/NOGO test after exposure to both red light and white light. Compared to dim light exposure, power in the alpha and alpha-theta regions was significantly decreased after exposure to red light. Melatonin levels were significantly suppressed by white light only. Results show that not only can red light improve measures of alertness, but it can also improve certain types of performance at night without affecting melatonin levels. These findings could have significant practical applications for nurses; red light could help nurses working rotating shifts maintain nighttime alertness, without suppressing melatonin or changing their circadian phase. © The Author(s) 2015.

The impact of chronotype on melatonin levels among shift workers.

PubMed

Bhatti, Parveen; Mirick, Dana K; Davis, Scott

2014-03-01

The association between shift work and cancer, which is thought to be mediated by effects on circulating melatonin levels, may be modified by chronotype (ie, the inherent preference for activity in the morning or the evening); however, few studies have examined the potential impact of chronotype on the carcinogenic effects of shift work. The authors analysed the impact of chronotype on previously reported differences in melatonin levels among healthcare workers that exclusively worked night or day shifts. The cross-sectional study included 664 men and women (310 day shift and 354 night shift workers) from which urine samples were collected throughout work and sleep periods and were assayed for 6-sulfatoxymelatonin. Participants also completed the Composite Scale of Morningness, a questionnaire used to assess chronotype. Among both morning and evening-type night shift workers, 6-sulfatoxymelatonin levels were constitutively lower during daytime sleep, night-time sleep and night work compared with day shift workers during night-time sleep. However, morning-type night shift workers consistently showed 6-sulfatoxymelatonin levels that were closer to levels in day shift workers than did evening-type night shift workers. Differences in 6-sulfatoxymelatonin levels between morning-type and evening-type night shift workers relative to day shift workers were statistically significant in every instance (p<0.05). These results suggest that morning-type night shift workers may be better able to maintain a 'normal' circadian pattern of melatonin production as compared with evening-type night shift workers. The impact of this chronotype effect on cancer risk among shift workers requires further study.

Preferred 11 different job rotation types in automotive company and their effects on productivity, quality and musculoskeletal disorders: comparison between subjective and actual scores by workers' age.

PubMed

Jeon, In Sik; Jeong, Byung Yong; Jeong, Ji Hyun

2016-10-01

This study investigates workers' favoured rotation types by their age and compares means between subjective and actual scores on productivity, quality and musculoskeletal disorders (MSDs). The subjects of research were 422 assembly line units in Hyundai Motor Company. The survey of 422 units focused on the workers' preference for 11 different rotation types and subjective scores for each type's perceived benefits, both by the workers' age. Then, actual scores on production-related indices were traced over a five-year period. The results suggest that different rotation types lead to different results in productivity, product quality and MSDs. Workers tend to perceive job rotation as a helpful method to enhance satisfaction, productivity and product quality more so than the actual production data suggests. Job rotation was especially effective in preventing MSDs for workers aged under 45, while its effects were not clear for the workers aged 45 years or older. Practitioner's Summary: This research presents appropriate rotation type for different age groups. Taking workers' age into account, administrators can use the paper's outcomes to select and implement the suitable rotation type to attain specific goals such as enhancing productivity, improving product quality or reducing MSDs.

The Impact of Chronotype on Melatonin Levels Among Shift Workers

PubMed Central

Bhatti, Parveen; Mirick, Dana K.; Davis, Scott

2015-01-01

Objectives The association between shift work and cancer, which is thought to be mediated by effects on circulating melatonin levels, may be modified by chronotype (i.e. the inherent preference for activity in the morning or the evening); however, few studies have examined the potential impact of chronotype on the carcinogenic effects of shift work. The authors analyzed the impact of chronotype on previously reported differences in melatonin levels among healthcare workers that exclusively worked night or day shifts. Methods The cross-sectional study included 664 men and women (310 day shift and 354 night shift workers) from which urine samples were collected throughout work and sleep periods and were assayed for 6-sulfatoxymelatonin. Participants also completed the Composite Scale of Morningness, a questionnaire used to assess chronotype. Results Among both morning and evening-type night shift workers, 6-sulfatoxymelatonin levels were constitutively lower during daytime sleep, nighttime sleep and night work compared to dayshift workers during nighttime sleep. However, morning-type shift workers consistently showed 6-sulfatoxymelatonin levels that were closer to levels in day shift workers than did evening-type night shift workers. Differences in 6-sulfatoxymelatonin levels between morning-type and evening-type night shift workers relative to day shift workers were statistically significant in every instance (p < 0.05). Conclusion These results suggest that morning-type night shift workers may be better able to maintain a ‘normal’ circadian pattern of melatonin production as compared to evening-type night shift workers. The impact of this chronotype effect on cancer risk among shift workers requires further study. PMID:24399070

Health consequences of shift-work: the case of iranian hospital security personnel.

PubMed

Abedini, Roghayeh; Soltanzadeh, Ahmad; Faghih, Mohammad Amin; Mohammadi, Heidar; Kamalinia, Mojtaba; Mohraz, Majid Habibi; Arassi, Maziyar; Veyseh, Peyman Piran; Aghaei, Hamed; Hosseini, Seyed Younes

2015-01-01

Shift-work, which is an ergonomics issue in workplaces, can negatively affect workers. The security personnel of medical centers in Iran have multiple responsibilities and consequently are exposed to such unwanted situations as observing patients, disputing with patient's attendants, unwanted shift schedules, and being away from family for long periods. This study assessed health problems of Iranian hospital security personnel (shift-worker personnel) using the Survey of Shift-workers (SOS) questionnaire (Persian version). This cross-sectional study was conducted in seven medical centers (4 hospitals and 3 clinics). A total of 416 workers were surveyed: shift-workers (exposed group) (n=209) and non-shift-workers (unexposed group) (n=207). The prevalence of adverse health effects was higher in shift-workers than day-workers. The level of education and mean Body Mass Index (BMI) in shift-workers were significantly higher compared with day-workers. The prevalence of gastrointestinal disorders, cardiovascular and psychological problems were also significantly higher in shift-workers compared with day-workers. Overall, the prevalence of health problems among the security personnel of medical centers was high. Hence, it is recommended that personnel be put under periodic monitoring and receive medical counseling and treatment if there is any disorder.

Night shift work and stomach cancer risk in the MCC-Spain study.

PubMed

Gyarmati, Georgina; Turner, Michelle C; Castaño-Vinyals, Gemma; Espinosa, Ana; Papantoniou, Kyriaki; Alguacil, Juan; Costas, Laura; Pérez-Gómez, Beatriz; Martin Sanchez, Vicente; Ardanaz, Eva; Moreno, Victor; Gómez-Acebo, Inés; Fernández-Tardon, Guillermo; Villanueva Ballester, Vicent; Capelo, Rocio; Chirlaque, Maria-Dolores; Santibáñez, Miguel; Pollán, Marina; Aragonés, Nuria; Kogevinas, Manolis

2016-08-01

Night shift work has been classified as a probable human carcinogen by the International Agency for Research on Cancer, based on experimental studies and limited evidence on human breast cancer risk. Evidence at other cancer sites is scarce. We evaluated the association between night shift work and stomach cancer risk in a population-based case-control study. A total of 374 incident stomach adenocarcinoma cases and 2481 population controls were included from the MCC-Spain study. Detailed data on lifetime night shift work were collected including permanent and rotating shifts, and their cumulative duration (years). Adjusted unconditional logistic regression models were used in analysis. A total of 25.7% of cases and 22.5% of controls reported ever being a night shift worker. There was a weak positive, non-significant association between ever having had worked for at least 1 year in permanent night shifts and stomach cancer risk compared to never having worked night shifts (OR=1.2, 95% CI 0.9 to 1.8). However, there was an inverse 'U' shaped relationship with cumulative duration of permanent night shifts, with the highest risk observed in the intermediate duration category (OR 10-20 years=2.0, 95% CI 1.1 to 3.6) (p for trend=0.19). There was no association with ever having had worked in rotating night shifts (OR=0.9, 95% CI 0.6 to 1.2) and no trend according to cumulative duration (p for trend=0.68). We found no clear evidence concerning an association between night shift work and stomach cancer risk. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Effect of Shift Work on Nocturia.

PubMed

Kim, Jin Wook

2016-01-01

To identify the circadian sensitive component of nocturia by comparing nocturia in patients who voluntarily choose a disrupted circadian rhythm, that is, shift workers, with those who maintain normal day-night cycles. Between 2011 and 2013, a total of 1741 untreated patients, 1376 nonshift workers and 365 shift workers, were compared for nocturia indices based on frequency volume charts (FVCs). General linear model of 8-hour interval urine production and frequency were compared between FVCs of nonshift workers, FVCs of night-shift workers, and FVCs of day-shift workers. Nocturia frequency was increased in the night-shift workers (2.38 ± 1.44) compared with nonshift workers (2.18 ± 1.04) (P <.01). Whereas nocturnal polyuria index did not increase significantly (0.33 ± 0.19 for night-shift workers, 0.34 ± 0.13 for nonshift workers, P = .24), nocturnal bladder capacity index increased significantly (1.41 ± 1.06 for night-shift workers, 1.26 ± 0.92 for nonshift workers, P <.01). Eight-hour interval indices show that urine production changed with shift (P <.01), whereas voiding frequency remains unchanged despite shift changes (P = .35). Patients in alternating work shifts showed increased nocturia, especially during their night shift. These changes tended to be more associated with decreased nocturnal bladder capacity than increased nocturnal polyuria. Copyright © 2015 Elsevier Inc. All rights reserved.

Association between rotating night shift work and risk of coronary heart disease among women

PubMed Central

Vetter, Céline; Devore, Elizabeth E.; Wegrzyn, Lani R.; Massa, Jennifer; Speizer, Frank E.; Kawachi, Ichiro; Rosner, Bernard; Stampfer, Meir J.; Schernhammer, Eva S.

2016-01-01

Importance Prospective studies linking shift work to coronary heart disease (CHD) have been inconsistent and limited by short follow-up. Objective Determine whether rotating night shift work is associated with CHD risk. Design, Setting and Participants Prospective cohort study of 189,158 initially healthy women followed over 24 years in the Nurses' Health Studies (NHS (1988-2012): N=73,623, and NHS2 (1989-2013): N=115,535). Exposure Questionnaire-based lifetime history of rotating night shift work (≥3 night shifts/month, plus day and evening shifts) at baseline; also updated every 2-4yrs in NHS2. Main Outcomes and Measures Incident CHD, i.e. non-fatal myocardial infarction, CHD death, angiogram-confirmed angina pectoris, coronary artery bypass grafting (CABG), stents, and angioplasty. Results During follow-up, 7,303 incident CHD cases in NHS (mean age at baseline: 54.5yrs) and 3,519 in NHS2 (34.8yrs) occurred. In multivariable adjusted Cox proportional hazards models, increasing years of baseline rotating night shift work were associated with a significantly higher CHD risk in both cohorts (NHS: age-standardized incidence rate (IR)<5yrs per 100,000 person-years=435.1, hazard ratio (HR)<5yrs=1.02, 95% confidence interval (CI)=0.97-1.08, IR5-9yrs=525.7, HR5-9yrs=1.12, 95%CI=1.02-1.22, IR≥10yrs=596.9, HR≥10yrs=1.18, 95%CI=1.10-1.26; Ptrend<0.001; NHS2: IR<5yrs=130.6, HR<5yrs=1.05, 95%CI=0.97-1.13; IR5-9yrs=151.6, HR5-9yrs=1.12, 95%CI=0.99-1.26; HR≥10yrs=178.0, HR≥10yrs=1.15, 95%CI=1.01-1.32; Ptrend=0.01), compared to women who never worked rotating night shifts (NHS: IRnever=425.5, NHS2: IRnever=122.6). In NHS, the association between duration of rotating night shift work and CHD was stronger in the first half of follow-up (IR<5yrs=382.4, HR<5yrs=1.10, 95%CI=1.01-1.21, IR5-9yrs=483.1, HR5-9yrs=1.19, 95%CI=1.03-1.39, IR≥10yrs=494.4, HR≥10yrs=1.27, 95%CI =1.13-1.42, Ptrend <0.001) than in the second half (IR<5yrs=424.8, HR<5yrs=0.98, 95%CI=0.92-1.05, IR5-9yrs=520.7, HR5-9yrs=1.08, 95%CI=0.96-1.21, IR≥10yrs=556.2, HR≥10yrs=1.13, 95%CI =1.04-1.24, Ptrend=0.004, PInteraction=0.02), suggestive of waning risk after cessation of shift work. Longer time since quitting shift work was associated with decreased CHD risk among ever shift workers in NHS2 (Ptrend<0.001). Conclusions and Relevance Among women who worked as registered nurses, longer duration of rotating night shift work was associated with a statistically significant, but small absolute increase in CHD risk. Further research is needed to explore whether the association is related to specific work hours and individual characteristics. PMID:27115377

Shift schedules, work factors, and mental health among onshore and offshore workers in the Norwegian petroleum industry

PubMed Central

BERTHELSEN, Mona; PALLESEN, Ståle; BJORVATN, Bjørn; KNARDAHL, Stein

2015-01-01

The purpose of the present study was to answer the following research questions: (1) Do workers in different shift schedules differ in mental distress? (2) Do workers in different shift schedules differ in neuroticism? (3) Do shift schedules differ in psychosocial work exposures? (4) Do psychosocial work exposures contribute to mental distress among onshore- and offshore workers? (5) Does neuroticism confound the association between work exposures and mental distress? Workers on six shift-schedules answered a questionnaire (1,471 of 2,628 employees). Psychological and social work factors were measured by QPSNordic, mental distress was measured by HADS and neuroticism was measured by EPQ. The results showed 1) No differences in mental distress between workers in different shift schedules, 2) Revolving-shift workers reported higher neuroticism compared to day workers, 3) Swing-shift workers and revolving-shift workers reported lower job control compared to permanent-night and -day workers, 4) Job demands and role conflict were associated with more mental distress. Job control, role clarity, support, and leadership were associated with lower mental distress, 5) Neuroticism influenced the relationship between psychosocial work factors and mental distress. The present study did not find differences in mental distress between shift schedules. Job characteristics may be contributing factors when determining health effects of shift work. PMID:25740007

Shift schedules, work factors, and mental health among onshore and offshore workers in the Norwegian petroleum industry.

PubMed

Berthelsen, Mona; Pallesen, Ståle; Bjorvatn, Bjørn; Knardahl, Stein

2015-01-01

The purpose of the present study was to answer the following research questions: (1) Do workers in different shift schedules differ in mental distress? (2) Do workers in different shift schedules differ in neuroticism? (3) Do shift schedules differ in psychosocial work exposures? (4) Do psychosocial work exposures contribute to mental distress among onshore- and offshore workers? (5) Does neuroticism confound the association between work exposures and mental distress? Workers on six shift-schedules answered a questionnaire (1,471 of 2,628 employees). Psychological and social work factors were measured by QPSNordic, mental distress was measured by HADS and neuroticism was measured by EPQ. The results showed 1) No differences in mental distress between workers in different shift schedules, 2) Revolving-shift workers reported higher neuroticism compared to day workers, 3) Swing-shift workers and revolving-shift workers reported lower job control compared to permanent-night and -day workers, 4) Job demands and role conflict were associated with more mental distress. Job control, role clarity, support, and leadership were associated with lower mental distress, 5) Neuroticism influenced the relationship between psychosocial work factors and mental distress. The present study did not find differences in mental distress between shift schedules. Job characteristics may be contributing factors when determining health effects of shift work.

Job strain and shift work influences on biomarkers and subclinical heart disease indicators: a pilot study.

PubMed

Wong, Imelda S; Ostry, Aleck S; Demers, Paul A; Davies, Hugh W

2012-01-01

This pilot study is one of the first to examine the impact of job strain and shift work on both the autonomic nervous system (ANS) and the hypothalamic-pituitary-adrenal (HPA) axis using two salivary stress biomarkers and two subclinical heart disease indicators. This study also tested the feasibility of a rigorous biological sampling protocol in a busy workplace setting. Paramedics (n = 21) self-collected five salivary samples over 1 rest and 2 workdays. Samples were analyzed for α-amylase and cortisol diurnal slopes and daily production. Heart rate variability (HRV) was logged over 2 workdays with the Polar RS800 Heart Rate monitors. Endothelial functioning was measured using fingertip peripheral arterial tonometry. Job strain was ascertained using a paramedic-specific survey. The effects of job strain and shift work were examined by comparing paramedic types (dispatchers vs. ambulance attendants) and shift types (daytime vs. rotating day/night). Over 90% of all expected samples were collected and fell within expected normal ranges. Workday samples were significantly different from rest day samples. Dispatchers reported higher job strain than ambulance paramedics and exhibited reduced daily alpha-amylase production, elevated daily cortisol production, and reduced endothelial function. In comparison with daytime-only workers, rotating shift workers reported higher job strain, exhibited flatter α-amylase and cortisol diurnal slopes, reduced daily α-amylase production, elevated daily cortisol production, and reduced HRV and endothelial functioning. Despite non-statistically significant differences between group comparisons, the consistency of the overall trend in subjective and objective measures suggests that exposure to work stressors may lead to dysregulation in neuroendocrine activity and, over the long-term, to early signs of heart disease. Results suggest that further study is warranted in this population. Power calculations based on effect sizes in the shift type comparison suggest a study size of n = 250 may result in significant differences at p = 0.05. High compliance among paramedics to complete the intensive protocol suggests this study will be feasible in a larger population.

Does age affect the relationship between control at work and sleep disturbance for shift workers?

PubMed

Loudoun, Rebecca Jane; Muurlink, Olav; Peetz, David; Murray, Georgina

2014-12-01

Among miners, shift work, aging and lack of control at work may be factors leading to increased sleep problems. Such risk factors may also operate in interaction, resulting in an even increased harm for sleep disruption. The present study aims at evaluating these relationships drawing on a sample of Australian mine and energy workers and their partners. The workers were mainly men. All performed shift work that included either nights (95%) or multiple shifts (92%), usually both (87%), while 36% were aged 50 years or above. The results show that low latitude over work activities is associated with higher sleep disturbances across the sample, though the effects are clearer amongst younger workers. By contrast, for younger workers, control over shift scheduling is not associated with sleep disturbances but for workers aged 50 or more, low control results in more sleep disturbance. Misalignment between shift workers and partner work schedules, and partner dissatisfaction with shift worker's employment and shift worker's work-life balance, are also associated with more sleep disturbances amongst shift workers.

The effect of sleep on item recognition and source memory recollection among shift-workers and permanent day-workers.

PubMed

Mawdsley, Matthew; Grasby, Katrina; Talk, Andrew

2014-10-01

We studied the effect of sleep versus wakefulness on item recognition and source memory recollection in a sample of shift-workers and permanent day-workers. Recognition of words that were previously viewed arrayed in quadrants of a page, and recollection of the original source location of the words on the page were assessed after a 12-h retention interval that was filled with wakefulness incorporating the subjects' work-shift, or an equal period that included sleep. Both shift-workers and permanent day-workers had poorer item recognition and source memory recollection when the retention interval was spent awake rather than including sleep. Shift-workers expressed larger deficits in performance than day-workers after wakefulness. This effect was not mediated by whether the shift-workers were on a day- or night-shift at the time of the study. These results indicate that sleep is an important contributor to successful item recognition and source recollection, and that mnemonic processing in shift-workers may be especially sensitive across their work-shift. © 2014 European Sleep Research Society.

Shift work and its association with metabolic disorders.

PubMed

Brum, Maria Carlota Borba; Filho, Fábio Fernandes Dantas; Schnorr, Claudia Carolina; Bottega, Gustavo Borchardt; Rodrigues, Ticiana C

2015-01-01

Although the health burden of shift work has not been extensively studied, evidence suggests that it may affect the metabolic balance and cause obesity and other metabolic disorders. Sleep deprivation, circadian desynchronization and behavioral changes in diet and physical activity are among the most commonly mentioned factors in studies of the association between night work and metabolic disorders. Individual adaptation to night work depends greatly on personal factors such as family and social life, but occupational interventions may also make a positive contribution to the transition to shift work, such as exposure to bright lights during the night shift, melatonin use, shift regularity and clockwise rotation, and dietary adaptations for the metabolic needs of night workers. The evaluation of the impact of night work on health and of the mechanisms underlying this relationship can serve as a basis for intervention strategies to minimize the health burden of shift work. This review aimed to identify highlights regarding therapeutic implications following the association between night and shift work and metabolic disorders, as well as the mechanisms and pathways responsible for these relationships.

Fuel Cell Using the Protic Ionic Liquid and Rotator Phase Solid Electrolyte Principles

DTIC Science & Technology

2008-07-15

appropriate host for the ionic liquid. (a) Papers published in peer-reviewed journals (N/A for none) [1] Thompson J, Dunn P, Holmes L, Belieres J-P...Names of Post Doctorates PERCENT_SUPPORTEDNAME Jean-Philippe Belieres 0.50 Xiaoguang Sun 0.50 1.00FTE Equivalent: 2Total Number: Names of Faculty...chemical shift for transferred protons (co-worker Jean-Philippe Belieres ) This is a fundamental study of the chemical state of the proton on the cation

Circadian Disruptions of Heart Rate Variability among Weekly Consecutive-12-hour 2 Shift Workers in the Automobile Factory in Korea.

PubMed

Son, Mia; Sung, Juhon; Yum, Myunggul; Kong, Jung Ok; Lee, Hye Un; Kim, In A; Kim, Jung Yeon

2004-05-01

The objective of this study is to compare the circadian patterns of heart rate variability assessed by 24-hour ambulatory electrocardiographic (ECG) recordings during day shift and night shift among the workers in the 5 days-concecutive- 12-hour shift in an automobile factory in Korea. The study population consisted 300 workers, who were randomly selected among the 8700 total workers in one car factory. To analyse circadian variation, the 24-hour ECG recordings (Marquette) were measured during day shift (08: 00-20: 00 h) and night shift (20: 00-08: 00 h). Analysis was performed for all time and frequency domain measures of HRV. 233 workers completed taking 24-hour ECG recordings. This study shows that the 24 hourcircadian variation mainly follows work/sleep cycle rather than day/night cycle among shift workers. This study also shows that among the night shift, the circadian variation between work and sleep cycle decreased compared to the work/sleep cycle among day shift workers. All time and frequency domain parameters (except LF/HF ratio) show significantly different between work and sleep in the day shift and night shift. These changes in heart rate variability circadian rhythms reflect significant reductions in cardiac parasympathetic activity with the most marked reduction in normal vagal activity among the shift workers. Especially, it suggests the circadian rhytm has blunted among the night workers. The quantification of the circadian variation in HRV can be a surrogates of workers' potential health risk, as well as suggests possible mechanisms through which the shift works compromise workers' health.

Shift workers have similar leisure-time physical activity levels as day workers but are more sedentary at work.

PubMed

Hulsegge, Gerben; Gupta, Nidhi; Holtermann, Andreas; Jørgensen, Marie Birk; Proper, Karin I; van der Beek, Allard J

2017-03-01

Objective Physical inactivity has been hypothesized as an underlying factor for the association between shift work and adverse health outcomes. We compared leisure-time and occupational physical activity and sedentary behavior between day, night, and non-night shift workers. Methods We identified 612 day workers, 139 night shift workers and 61 non-night shift workers aged 18-65 years (54% men) in two Danish studies: the New method for Objective Measurements of physical Activity in Daily living (NOMAD) and the Danish Physical ACTivity cohort with Objective measurements (DPhacto) between 2011-2013. Sedentary behavior, light, and moderate-to-vigorous physical activity were measured using an accelerometer. Physical activity was expressed as percentage of leisure and work time spent in each activity. Linear regression analyses were used to test differences in physical activity and sedentary behavior between day, night, and non-night shift workers. Results No differences in leisure-time sedentary behavior and physical activity were observed between day and shift workers (P>0.05). Non-night shift workers spent 7.2% [95% confidence interval (95% CI) 2.3-12.1) more time in occupational sedentary behavior than day workers and 5.9% (95% CI -10.1- -1.7) and 1.9% (95% CI -3.7- -0.2) less time in occupational light and moderate-to-vigorous physical activity, respectively. Compared to day workers, night shift workers spent 4.3% (95% CI 2.4-6.1) more time at work in uninterrupted sedentary periods of ≥30 minutes. Conclusions Shift workers had similar leisure-time physical activity patterns as day workers, but were more sedentary at work. Future research should elucidate whether occupational physical inactivity and sedentary behavior contributes to shift work-related adverse health effects.

Attitudes towards rotating shift work in clinical nurses: a Q-methodology study.

PubMed

Ha, Eun-Ho

2015-09-01

To identify clinical nurses' attitudes towards rotating shift work. Many hospitals worldwide employ rotating shift work patterns to staff their facilities. Attitudes of clinical nurses towards rotating shift work vary. To understand clinical nurses' attitudes towards rotating shift work, Q-methodology, a method for the analysis of subjective viewpoints with the strengths of both qualitative and quantitative methods, was used. Forty-six selected Q-statements from each of the 39 participants were classified into a normal distribution using an 11-point bipolar scale. The collected data were analysed using pc-QUANL program. Three discrete factors emerged as follows: factor I (rotating shift work is frustrating: objectionable perspective), factor II (rotating shift work is satisfactory: constructive perspective) and factor III (rotating shift work is problematic, but necessary: ambivalent perspective). The subjective viewpoints of the three identified factors can be applied in developing various roster designs for nurses engaging in rotating shift work. The findings provide the baseline for nurse leaders in helping nurses adjust and deal with rotating shift work. © 2015 John Wiley & Sons Ltd.

Night shift work and levels of 6-sulfatoxymelatonin and cortisol in men.

PubMed

Mirick, Dana K; Bhatti, Parveen; Chen, Chu; Nordt, Frank; Stanczyk, Frank Z; Davis, Scott

2013-06-01

Night shift work is associated with cancer among men, but the biologic mechanism is unclear. We investigated whether male night shift workers showed changes in levels of melatonin and cortisol, potential biomarkers of cancer risk. Urine was collected from 185 night shift and 158 day shift-working male healthcare providers, aged 22 to 55 years, throughout work and sleep periods, and assayed for 6-sulfatoxymelatonin and cortisol. Morning serum was collected within 90 minutes of completing the night and assayed for cortisol. Night shift workers had significantly lower 6-sulfatoxymelatonin levels during daytime sleep, nighttime work, and nighttime sleep on off-nights (57%, 62%, and 40% lower, respectively), relative to the day shift workers during nighttime sleep (P < 0.0001); urinary cortisol in night shift workers was 16% higher during daytime sleep and 13% lower during nighttime sleep on off-nights (P < 0.05). Morning serum cortisol post-work and post-sleep in night shift workers were 24% and 43% lower, respectively, than post-sleep levels among day shift workers (P < 0.0001). Within-subject comparisons among the night shift workers revealed significantly lower melatonin levels and significantly higher urinary cortisol levels during daytime sleep and nighttime work, relative to nighttime sleep (P < 0.01); morning serum cortisol levels post-work were lower than those post-sleep. Night shift workers have substantially lower 6-sulfatoxymelatonin during night work and daytime sleep, and levels remain low when night shift workers sleep at night. Chronic reduction in melatonin among night shift workers may be an important carcinogenic mechanism. Cortisol secretion patterns may be impacted by night shift work, which could affect cancer risk. Shift work could be an important risk factor for many types of cancer.

Health and Occupational Outcomes Among Injured, Nonstandard Shift Workers.

PubMed

Wong, Imelda S; Smith, Peter M; Mustard, Cameron A; Gignac, Monique A M

2015-11-01

This study compares health and occupational outcomes following a work-related injury for nonstandard and day-shift workers. National Population Health Survey data were used to explore outcomes 2 years post-work injury. Retrospective-matched cohort analyses examined main effects and interactions of shift schedule and work injury with changes in health, shift schedule, and labor force status. Models were adjusted for respondent characteristics, baseline health status, and occupational strength requirements. Injured nonstandard shift workers reported lower health utility index scores, compared with uninjured and injured daytime workers and uninjured nonstandard-shift workers. No significant interactions between shift and injury were found with schedule change and leaving the labor force. Injured nonstandard-shift workers are as likely to remain employed as other groups, but may be vulnerable in terms of diminished health.

Relationship between shift work and peripheral total and differential leukocyte counts in Chinese steel workers.

PubMed

Lu, Li-Fen; Wang, Chao-Ping; Tsai, I-Ting; Hung, Wei-Chin; Yu, Teng-Hung; Wu, Cheng-Ching; Hsu, Chia-Chang; Lu, Yung-Chuan; Chung, Fu-Mei; Jean, Mei-Chu Yen

2016-01-01

Even though shift work has been suspected to be a risk factor for cardiovascular disease, little research has been done to determine the logical underlying inflammation mechanisms. This study investigated the association between shift work and circulating total and differential leukocyte counts among Chinese steel workers. The subjects were 1,654 line workers in a steel plant, who responded to a cross-sectional survey with a questionnaire on basic attributes, life style, and sleep. All workers in the plant received a periodic health checkup. Total and differential leukocytes counts were also examined in the checkup. Shift workers had higher rates of alcohol use, smoking, poor sleep, poor physical exercise, and obesity than daytime workers. In further analysis, we found that the peripheral total WBC, monocyte, neutrophil, and lymphocyte counts were also greater in shift workers than in daytime workers. When subjects were divided into quartiles according to total WBC, neutrophil, monocyte, and lymphocyte counts, increased leukocyte count was associated with shift work. Using stepwise linear regression analysis, smoking, obesity, and shift work were independently associated with total WBC, monocyte, neutrophil, and lymphocyte counts. This study indicates that peripheral total and differential leukocyte counts are significantly higher in shift workers, which suggests that shift work may be a risk factor of cardiovascular disease. Applicable intervention strategies are needed for prevention of cardiovascular disease for shift workers.

Sleep interruption associated with house staff work schedules alters circadian gene expression.

PubMed

Fang, Ming Zhu; Ohman-Strickland, Pamela; Kelly-McNeil, Kathie; Kipen, Howard; Crabtree, Benjamin F; Lew, Jenny Pan; Zarbl, Helmut

2015-11-01

Epidemiological studies indicate that disruption of circadian rhythm by shift work increases the risk of breast and prostate cancer. Our studies demonstrated that carcinogens disrupt the circadian expression of circadian genes (CGs) and circadian-controlled genes (CCGs) during the early stages of rat mammary carcinogenesis. A chemopreventive regimen of methylselenocysteine (MSC) restored the circadian expression of CGs and CCGs, including PERIOD 2 (PER2) and estrogen receptor β (ERS2), to normal. The present study evaluated whether changes in CG and CCG expression in whole blood can serve as indicators of circadian disruption in shift workers. Fifteen shift workers were recruited to a crossover study. Blood samples were drawn before (6 PM) and after (8 AM) completing a night shift after at least seven days on floating night-shift rotation, and before (8 AM), during (1 PM), and after (6 PM) completing seven days on day shift. The plasma melatonin level and messenger RNA (mRNA) expression of PER2, nuclear receptor subfamily 1, group d, member 1 (NR1D1), and ERS2 were measured, and the changes in levels of melatonin and gene expression were evaluated with statistical analyses. The mRNA expression of PER2 was affected by shift (p = 0.0079); the levels were higher in the evening for the night shift, but higher in the morning for the day shift. Increased PER2 expression (p = 0.034) was observed in the evening on the night versus day shifts. The melatonin level was higher in the morning for both day shifts (p = 0.013) and night shifts (p <0.0001). Changes in the level of PER2 gene expression can serve as a biomarker of disrupted circadian rhythm in blood cells. Therefore, they can be a useful intermediate indicator of efficacy in future MSC-mediated chemoprevention studies. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of the oral health problems and behavior of male daytime-only and night-shift office workers: An Internet survey

PubMed Central

Ishizuka, Yoichi; Yoshino, Koichi; Takayanagi, Atsushi; Sugihara, Naoki; Maki, Yoshinobu; Kamijyo, Hideyuki

2016-01-01

Objective: The aim of this study was to compare the oral health problems and behavior of full-time male daytime-only and night shift office workers. Methods: The participants were recruited by applying screening procedures to a pool of Japanese registrants in an online database. During the period of 20 February 2015 to 11 March 2015, participants were asked to complete a questionnaire about their oral health. A total of 325 daytime-only workers and 351 workers who sometimes worked night shifts, ages 30 to 69, were analyzed in this study. Results: Overall, the mean number of teeth of the night shift workers was lower than that of the daytime-only workers (p=0.002). When analyzed by age group, a significant difference was seen in the 50-69 age group (p=0.016). The percentage of night shift workers with decayed teeth was higher than that of the daytime-only workers (p<0.001). The night shift workers were more likely to report gingival bleeding (p=0.015) and stomatitis (p=0.025) than the daytime-only workers. The percentage of night shift workers reporting frequent brushing behavior was lower than that of the daytime-only workers (p=0.040). The independent variables found to correlate significantly with tooth decay were night shift work (OR, 1.79; 95% CI, 1.20-2.67), current smoking habit (OR, 1.66; 95% CI, 1.13-2.46), and BMI of ≥25 (OR, 1.56; 95% CI, 1.02-2.39). Conclusions: These results indicate a relationship between night shift work and oral health problems. Night shift workers may require additional support for oral health maintenance. PMID:27010087

Comparison of the oral health problems and behavior of male daytime-only and night-shift office workers: An Internet survey.

PubMed

Ishizuka, Yoichi; Yoshino, Koichi; Takayanagi, Atsushi; Sugihara, Naoki; Maki, Yoshinobu; Kamijyo, Hideyuki

2016-05-25

The aim of this study was to compare the oral health problems and behavior of full-time male daytime-only and night shift office workers. The participants were recruited by applying screening procedures to a pool of Japanese registrants in an online database. During the period of 20 February 2015 to 11 March 2015, participants were asked to complete a questionnaire about their oral health. A total of 325 daytime-only workers and 351 workers who sometimes worked night shifts, ages 30 to 69, were analyzed in this study. Overall, the mean number of teeth of the night shift workers was lower than that of the daytime-only workers (p=0.002). When analyzed by age group, a significant difference was seen in the 50-69 age group (p=0.016). The percentage of night shift workers with decayed teeth was higher than that of the daytime-only workers (p<0.001). The night shift workers were more likely to report gingival bleeding (p=0.015) and stomatitis (p=0.025) than the daytime-only workers. The percentage of night shift workers reporting frequent brushing behavior was lower than that of the daytime-only workers (p=0.040). The independent variables found to correlate significantly with tooth decay were night shift work (OR, 1.79; 95% CI, 1.20-2.67), current smoking habit (OR, 1.66; 95% CI, 1.13-2.46), and BMI of ≥25 (OR, 1.56; 95% CI, 1.02-2.39). These results indicate a relationship between night shift work and oral health problems. Night shift workers may require additional support for oral health maintenance.

Circadian Rhythm of Wrist Temperature among Shift Workers in South Korea: A Prospective Observational Study

PubMed Central

Kim, Hyunjoo; Kang, Suk-Hoon; Choo, Sang-Hyo; Lee, In-Seok; Choi, Kyung-Hwa

2017-01-01

Background: Human body temperature varies with circadian rhythm. To determine the effect of shift work on the circadian rhythm of the distal-skin temperature, wrist temperatures were measured. Methods: Wrist-skin temperatures were measured by an iButton® Temperature Logger. It was measured every 3 min for two and eight consecutive working days in the day and shift workers, respectively. Mesor, amplitude, and acrophase were measured by Cosinor analysis. Results: The shift-worker amplitude dropped significantly as the night shift progressed (0.92 to 0.85 °C), dropped further during rest (0.69 °C), and rose during the morning-shift days (0.82 °C). Day workers still had higher amplitudes (0.93 °C) than the morning-shift workers. The acrophase was delayed during the four night-shift days, then advanced during rest days and the morning-shift days. Nevertheless, the morning-shift worker acrophase was still significantly delayed compared to the day workers (08:03 a.m. vs. 04:11 a.m.). Conclusions: The further reduction of wrist-temperature amplitude during rest after the night shift may be due to the signal circadian rhythm disruption. Reduced amplitudes have been reported to be associated with intolerance to shift work. The findings of our study may help to design the most desirable schedule for shift workers. PMID:28946653

Circadian Rhythm of Wrist Temperature among Shift Workers in South Korea: A Prospective Observational Study.

PubMed

Jang, Tae-Won; Kim, Hyunjoo; Kang, Suk-Hoon; Choo, Sang-Hyo; Lee, In-Seok; Choi, Kyung-Hwa

2017-09-24

Background : Human body temperature varies with circadian rhythm. To determine the effect of shift work on the circadian rhythm of the distal-skin temperature, wrist temperatures were measured. Methods : Wrist-skin temperatures were measured by an iButton ® Temperature Logger. It was measured every 3 min for two and eight consecutive working days in the day and shift workers, respectively. Mesor, amplitude, and acrophase were measured by Cosinor analysis. Results : The shift-worker amplitude dropped significantly as the night shift progressed (0.92 to 0.85 °C), dropped further during rest (0.69 °C), and rose during the morning-shift days (0.82 °C). Day workers still had higher amplitudes (0.93 °C) than the morning-shift workers. The acrophase was delayed during the four night-shift days, then advanced during rest days and the morning-shift days. Nevertheless, the morning-shift worker acrophase was still significantly delayed compared to the day workers (08:03 a.m. vs. 04:11 a.m.). Conclusions : The further reduction of wrist-temperature amplitude during rest after the night shift may be due to the signal circadian rhythm disruption. Reduced amplitudes have been reported to be associated with intolerance to shift work. The findings of our study may help to design the most desirable schedule for shift workers.

[Investigation and Analysis on shift work female workers' and the impact on reproductive health].

PubMed

Yu, C Y; Yu, W L; Xu, M; Xing, Z L

2018-02-20

Objective: To investigate the distribution of shift work of female workers in different industries and the relationship between shift work and reproductive health, then provide reference for the female workers' labor protection. Methods: From June to September 2016, cluster sampling questionnaire survey was performed among female workers from 11 industries including electronics, medicine and health, pharmacy. To investigate the general information, shift - work information, reproductive health and childbearing history of these female workers. Results: A total of 63 711 usable questionnaires were collected, resulting in a response rate of 96.94%.A total of 13 546 workers worked in shifts, accounting for 21.26%, the highest proportion was in the medical industry 30.61%, metallurgy 30.81%, petrochemical engineerin 26.78% respectively. Compared with the workers who did not work in shifts, those who worked in shifts had significantly higher rate of abnormal menstruation, rate of reproductive system infection in married workers, the rate of infertility (χ(2)=19.108、10.673、21.510, P <0.05) ; Compared with the workers who did not work in nightshifts, those who worked in nightshifts had significantly higher rate of abnormal menstruation, rate of reproductive system infection among married workers and rate of infertility (χ(2)=140.043、71.901、29.024, P <0.01) . Conclusion: The highest rate of shift work was in the medical industry, metallurgy, petrochemical engineering industry. Workers who worked in shifts have serious reproductive health issues, the occurrence of abnormal menstruation, reproductive system infection and infertility may associated with shift work.

Shift and Day Work: A Comparison of Sickness Absence, Lateness, and other Absence Behaviour at an Oil Refinery from 1962 to 1965

PubMed Central

Taylor, P. J.

1967-01-01

Despite the increasing use of continuous process shift work in modern industry, few studies on the medical aspects of shift work can be found in recent literature of occupational health. Physiologists have shown that the ability of the body to adjust its circadian rhythms to alteration in hours of work or sleep can take up to a month. The usual type of shift work in industry involves weekly changes of hours, and thus on theoretical grounds at least this may not be the most suitable frequency for shift changes. Sickness absence of male refinery workers has been studied over a four-year period. The figures show that continuous three-cycle shift workers have consistently and significantly lower rates of sickness than day workers in similar occupations. The annual inception rate (spells) standardized for age was 108% for shift workers and 182% for day workers, and the average annual duration per man was 11 days for shift workers and 18 days for day workers, although the average length of spell was slightly longer among shift workers. As far as is known, such a difference has not been described before in detail. Age-related lateness and absenteeism have been measured and show similar wide differences between the two groups. Although both types of worker are largely self-selected, the difference is not due to medical selection or to an excess of any one type of disease in day workers. Over three-quarters of 150 shift workers interviewed stated that they preferred shift work hours and that sleeping difficulties were not common. It is suggested that the main reasons for the difference between shift and day workers' sickness absence lie in the degree of personal involvement in the work and in the social structure of the working group. PMID:6023084

Late chronotype and high social jetlag are associated with burnout in evening-shift workers: Assessment using the Chinese-version MCTQshift.

PubMed

Cheng, Wan-Ju; Hang, Liang-Wen

2018-04-16

Chronotypes are associated with shift work tolerance and sleep in shift workers, and sleep mediates the impact of shift work on mental health. However, the role of chronotype in the association between shift work and mental health has not been clarified. In this study, we aimed to examine the association between chronotype and burnout in shift workers, using the validated Munich ChronoType Questionnaire for shift workers (MCTQ shift ). A total of 288 shift workers with irregular shift frequencies were recruited and completed the Chinese-version MCTQ shift and the Morningness-Eveningness Questionnaire (MEQ). Chronotypes were assessed by the calculation of corrected mid-sleep time (MSF SC ) from mid-sleep time on free days (MSF) based on their exact shift schedules. Another 26 evening-shift nurses were monitored with actigraphy for at least two consecutive evening shifts and the following two free days. Burnout was evaluated using the Copenhagen Burnout Inventory. We found that MSF E SC , MSF E and mid-sleep time on workdays (MSW E ) had normal distributions and correlated significantly with MEQ scores (r = - 0.47, -0.45 and -0.47, respectively; all p < 0.001). MSW was more closely correlated with actigraphy-derived mid-sleep time on the free day before workdays than that on workdays (r = 0.61 and 0.48, respectively, p < 0.05). Sleep duration was significantly longer on workdays among evening-shift workers who slept late on workdays than those who slept early (β = 0.59, p < 0.001). After demographic and work characteristics were adjusted for in linear regression models, late chronotype and high social jetlag were associated with burnout scores in evening-shift workers. In conclusion, the Chinese-version MCTQ shift is a valid tool for chronotype assessment. Interventions to improve sleep in shift workers should be tailored to chronotype due to variations in sleep behavior. Late chronotype may be an inherent feature of mental health problems, because the association with burnout was significant in both day workers in previous studies and shift workers.

Sleep Quality Associated With Different Work Schedules: A Longitudinal Study of Nursing Staff.

PubMed

Niu, Shu-Fen; Miao, Nae-Fang; Liao, Yuan-Mei; Chi, Mei-Ju; Chung, Min-Huey; Chou, Kuei-Ru

2017-07-01

To explore the differences in sleep parameters between nurses working a slow, forward rotating shift and those working a fixed day shift. A longitudinal parallel-group comparison design was used in this prospective study. Participants (female) were randomly assigned to a rotating shift or a fixed day shift group. Participants in the rotating shift group worked day shift for the first 4 weeks, followed by evening shift for the second and night shift the third. Those in the day shift group worked day shift for all 12 weeks. Each kept a sleep diary and wore an actigraph (actigraph data were used to calculate total sleep time [TST], sleep onset latency [SOL], wake after sleep onset [WASO], and sleep efficiency [SE]) for 12 days, from Workday 1-4 in each of Weeks 4, 8, and 12. TST in nurses working evening rotating shift was higher than that for those working the day or night rotating shift and fixed day shift. WASO was significantly longer on Day 2 for rotating shift participants working evening versus day shift. SOL and SE were significantly shorter and lower in rotating shift nurses working night versus both day and evening shifts. A comprehensive understanding of the sleep patterns and quality of nurses with different work shifts may lead to better management of work shifts that reduces the influence of shift work on sleep quality.

Sleep duration and sleep-related problems in different occupations in the Hordaland Health Study.

PubMed

Ursin, Reidun; Baste, Valborg; Moen, Bente E

2009-05-01

The aim of this study was to examine the relationship between occupation and sleep duration, sleepiness, insufficient sleep, and insomnia in day and shift workers (including night work and watches). The study was population-based and cross-sectional, and relied on self-administered questionnaires. It was conducted as part of the 1997-1999 Hordaland Health Study in collaboration with the Norwegian National Health Screening Service. Aged 40-45 years, 7782 participants answered a sleep questionnaire, reporting their occupation and whether or not they were employed in shift work. Our study found differences in sleep duration during the working week between occupational groups; in both shift and day workers. Craft workers, plant operators, and drivers slept less than leaders, and non-personal and personal service workers. Within some occupations (leaders, personal service workers, and plant operators), shift workers slept less than day workers. The mean sleep duration of shift workers was 15 minutes shorter than that of day workers. Rise times, but not bedtimes, were earlier in craft-and construction workers, plant operators, and drivers than in leaders and non-personal and personal service workers, particularly day workers. When adjusted for shift work and working hours - compared to leaders - craft workers, plant operators, and drivers had an increased risk of daytime sleepiness (odds ratio 1.5, 1.8, and 1.8 respectively) and of falling asleep at work (odds ratio 1.6, 2.1 and 2.0 respectively). Shift workers had an increased risk of falling asleep at work and insomnia. Occupation has separate effects on sleep duration and sleep-related problems, independent of the effects of shift work.

Shift work and burnout among health care workers.

PubMed

Wisetborisut, A; Angkurawaranon, C; Jiraporncharoen, W; Uaphanthasath, R; Wiwatanadate, P

2014-06-01

Burnout, defined as a syndrome derived from prolonged exposure to stressors at work, is often seen in health care workers. Shift work is considered one of the occupational risks for burnout in health care workers. To identify and describe the association between shift work and burnout among health care workers. A cross-sectional study of health care workers in Chiang Mai University Hospital, Thailand. Data were collected via an online self-answered questionnaire and included details of shift work and burnout. Burnout was measured by the Maslach Burnout Inventory (MBI). Two thousand seven hundred and seventy two health care workers participated, a 52% response rate. Burnout was found more frequently among shift workers than those who did not work shifts (adjusted odds ratio [aOR] 1.4, 95% confidence interval [CI]: 1.0-1.9). Among shift workers, over 10 years of being a shift worker was associated with increasing burnout (aOR 1.7, 95% CI: 1.2-2.6) and having 6-8 sleeping hours per day was associated with having less burnout (aOR 0.7, 95% CI: 0.5-0.9). Nurses who had at least 8 days off per month had lower odds of burnout compared with those with fewer than 8 days off (aOR 0.6, 95% CI: 0.5-0.8). Shift work was associated with burnout in this sample. Increased years of work as a shift worker were associated with more frequent burnout. Adequate sleeping hours and days off were found to be possible protective factors. Policies on shift work should take into account the potential of such work for contributing towards increasing burnout. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Physiological responses to unvarying (steady) and 2-2-1 shifts : Miami International Flight Service Station.

DOT National Transportation Integrated Search

1985-02-01

Two types of shift rotation in the same air traffic facility were investigated in order to determine the relative advantages and disadvantages of nonrotating shift work (steady shift) and rotating shift work. The rotating shift work chosen for compar...

Racial Differences in the Association Between Night Shift Work and Melatonin Levels Among Women

PubMed Central

Bhatti, Parveen; Mirick, Dana K.; Davis, Scott

2013-01-01

Reduced suppression of melatonin in response to working the night shift among people of Asian ancestry has been suggested as a possible explanation for the null results observed in a recent analysis of shift work and breast cancer risk in a Chinese cohort. The authors analyzed the impact of Asian versus white race on previously reported differences in urinary 6-sulfatoxymelatonin levels in a 2003–2008 study in Seattle, Washington, of female health-care workers that exclusively worked night or day shifts. A total of 225 white and 51 Asian participants were included in the analysis. Although 6-sulfatoxymelatonin levels were affected by night shift work in both racial groups, Asian night shift workers consistently showed 6-sulfatoxymelatonin levels that were closer to levels in day shift workers than did white night shift workers. Furthermore, differences in 6-sulfatoxymelatonin levels between white and Asian night shift workers relative to day shift workers were statistically significant in every instance (P < 0.05). These results suggest that Asians may be better able to maintain a “normal” circadian pattern of melatonin production compared with whites and suggest a biological mechanism by which Asian night shift workers may be at a reduced risk of cancer. PMID:23380044

Alteration in eating habits among shift workers of a poultry processing plant in southern Brazil.

PubMed

de Freitas, Elisângela da Silva; Canuto, Raquel; Henn, Ruth Liane; Olinto, Beatriz Anselmo; Macagnan, Jamile Block Araldi; Pattussi, Marcos Pascoal; Busnello, Fernanda Michelin; Olinto, Maria Teresa Anselmo

2015-08-01

The relationship between shift work and the eatinghabits of workers was investigated in a slaughterhouse in southern Brazil. It involved a cross-sectional study with 1,206 workers of both sexes between 18 and 50 years of age. A standardized questionnaire was used to gather demographic, socioeconomic, work shift and eating habit information. The shift of work was categorized into daytime and nighttime, based on the starting and ending times of the shift. The eating habits of workers were evaluated as follows: number and type of meals eaten during the 24 hours of a normal day, the inappropriateness of the hoursof these meals and the dietaryrisk score. This was built on the risk score of the weekly consumption of 13 food items. After adjusting for potential confounders, non-Caucasian and younger male workers were more likely to manifest eating risk habits. Nighttimeshift workers consumed ahigher number of meals/day with greater inappropriateness of meal times than daytimeshift workers. The night shift can negatively influence the eating habits of workers of that shift.

Restless Legs Syndrome/Willis-Ekbom Disease Is Prevalent in Working Nurses, but Seems Not to Be Associated with Shift Work Schedules.

PubMed

Waage, Siri; Pallesen, Ståle; Moen, Bente Elisabeth; Bjorvatn, Bjørn

2018-01-01

Insomnia and excessive sleepiness are among the most commonly reported sleep problems related to shift work. Sleep-related movement disorders have, however, received far less attention in relation to such work schedules. The objective of this study was to investigate the association between different shift work schedules and the prevalence of Restless legs syndrome/Willis-Ekbom disease (RLS/WED) in a large sample of Norwegian nurses. Our hypothesis was that shift working nurses would report higher prevalence of RLS/WED compared to day workers. A total of 1,788 nurses with different work schedules (day work, two-shift rotation, night work, three shift rotation) participated in a cohort study, started in 2008/2009. Four questions about RLS/WED based on the diagnostic criteria were included in wave 4 (2012). RLS/WED prevalence rates across different shift schedules were explored by the Pearson chi-square test. Logistic regression analysis was used to assess the association between RLS/WED and work schedules and shift work disorder (SWD) with adjustment for sex, age, marital status, smoking, and caffeine use. In total, 90.0% of the nurses were females, mean age 36.5 years (SD = 8.6, range 25-67). The overall prevalence of RLS/WED was 26.8%. We found no significant differences between the prevalence of RLS/WED across the different shift schedules, ranging from 23.3% (day work) to 29.4% (night work). There was a significant difference ( p  < 0.001) in the prevalence of RLS/WED between nurses having SWD (33.5%) compared to nurses not having SWD (23.8%). SWD remained significantly associated with RLS/WED in the adjusted logistic regression analysis (1.56, CI: 1.24-1.97). This study did not support the hypothesis. RLS/WED was associated with SWD, which might indicate that nurses vulnerable to shift work also are sensitive to other complaints related to a misalignment of the biological clock.

Reduced Tolerance to Night Shift in Chronic Shift Workers: Insight From Fractal Regulation.

PubMed

Li, Peng; Morris, Christopher J; Patxot, Melissa; Yugay, Tatiana; Mistretta, Joseph; Purvis, Taylor E; Scheer, Frank A J L; Hu, Kun

2017-07-01

Healthy physiology is characterized by fractal regulation (FR) that generates similar structures in the fluctuations of physiological outputs at different time scales. Perturbed FR is associated with aging and age-related pathological conditions. Shift work, involving repeated and chronic exposure to misaligned environmental and behavioral cycles, disrupts circadian coordination. We tested whether night shifts perturb FR in motor activity and whether night shifts affect FR in chronic shift workers and non-shift workers differently. We studied 13 chronic shift workers and 14 non-shift workers as controls using both field and in-laboratory experiments. In the in-laboratory study, simulated night shifts were used to induce a misalignment between the endogenous circadian pacemaker and the sleep-wake cycles (ie, circadian misalignment) while environmental conditions and food intake were controlled. In the field study, we found that FR was robust in controls but broke down in shift workers during night shifts, leading to more random activity fluctuations as observed in patients with dementia. The night shift effect was present even 2 days after ending night shifts. The in-laboratory study confirmed that night shifts perturbed FR in chronic shift workers and showed that FR in controls was more resilience to the circadian misalignment. Moreover, FR during real and simulated night shifts was more perturbed in those who started shift work at older ages. Chronic shift work causes night shift intolerance, which is probably linked to the degraded plasticity of the circadian control system. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Sleep disturbances among offshore fleet workers: a questionnaire-based survey.

PubMed

Hansen, Jakob Hønborg; Holmen, Ingunn Marie

2011-01-01

BACKGROUND. Shift work is related to fatigue and desynchronization with the external environment. This study investigates how 6-h shifts and 12-h shifts affects sleep and safety in workers onboard offshore supply vessels, and if any differences exist between the two working schedules. MATERIAL AND METHODS. A questionnaire study was carried out in the North Sea, Australia, Africa, South America, and the Far East, with 577 participants. The offshore fleet workers gave information on parameters related to sleep disturbances, causes of sleep disturbances, and safety. Regional differences in these parameters were also investigated. RESULTS. Workers on 6-hour shifts reported significantly more sleep problems than 12-hour shift workers did (p 〈 0.01). The 6-hour workers were more affected by noise (p 〈 0.01) and shift-work itself (p 〈 0.01). CONCLUSIONS. Those working 6-hour shifts suffer more from sleep disturbances than those on 12-hour shifts, but this is not reflected in the perception of safety within the individual. Noise and shift-work itself is more of a problem in the 12-hour workers. Differences in safety culture and work morale are likely to cause the differences between regions.

Prevalence of Sleep Disorders and Their Impacts on Occupational Performance: A Comparison between Shift Workers and Nonshift Workers

PubMed Central

Yazdi, Zohreh; Sadeghniiat-Haghighi, Khosro; Loukzadeh, Ziba; Elmizadeh, Khadijeh; Abbasi, Mahnaz

2014-01-01

The consequences of sleep deprivation and sleepiness have been noted as the most important health problem in our modern society among shift workers. The objective of this study was to investigate the prevalence of sleep disorders and their possible effects on work performance in two groups of Iranian shift workers and nonshift workers. This study was designed as a cross-sectional study. The data were collected by PSQI, Berlin questionnaire, Epworth Sleepiness Scale, Insomnia Severity Index, and RLS Questionnaire. Occupational impact of different sleep disorders was detected by Occupational Impact of Sleep Disorder questionnaire. These questionnaires were filled in by 210 shift workers and 204 nonshift workers. There was no significant difference in the age, BMI, marital status, and years of employment in the two groups. Shift workers scored significantly higher in the OISD. The prevalence of insomnia, poor sleep quality, and daytime sleepiness was significantly higher in shift workers. Correlations between OISD scores and insomnia, sleep quality, and daytime sleepiness were significant. We concluded that sleep disorders should receive more attention as a robust indicator of work limitation. PMID:24977041

Associations of Shift Work and Its Duration with Work-Related Injury among Electronics Factory Workers in South Korea.

PubMed

Ryu, Jia; Jung-Choi, Kyunghee; Choi, Kyung-Hwa; Kwon, Ho-Jang; Kang, Chungwon; Kim, Hyunjoo

2017-11-21

This study aimed to explore the association between shift work and work-related injuries. We collected data on workers from an electronics factory. This cross-sectional study included 13,610 subjects, who were assessed based on a self-reported questionnaire about their shift work experiences, work-related injuries, and other covariates. Multiple logistic regression models were used to evaluate the associations between shift work and work-related injuries and were estimated using the odds ratio. We found that the current and past shift workers, compared to non-shift workers, were associated with a 2.7- and 1.7-fold higher risk of work-related injury. There was a dose-response relationship between shift work duration and work-related injury among current female shift workers. Shift work increased the risk of work-related injuries, and the impact could be different depending on gender.

Associations of Shift Work and Its Duration with Work-Related Injury among Electronics Factory Workers in South Korea

PubMed Central

Ryu, Jia; Jung-Choi, Kyunghee; Choi, Kyung-Hwa; Kwon, Ho-Jang; Kang, Chungwon

2017-01-01

This study aimed to explore the association between shift work and work-related injuries. We collected data on workers from an electronics factory. This cross-sectional study included 13,610 subjects, who were assessed based on a self-reported questionnaire about their shift work experiences, work-related injuries, and other covariates. Multiple logistic regression models were used to evaluate the associations between shift work and work-related injuries and were estimated using the odds ratio. We found that the current and past shift workers, compared to non-shift workers, were associated with a 2.7- and 1.7-fold higher risk of work-related injury. There was a dose-response relationship between shift work duration and work-related injury among current female shift workers. Shift work increased the risk of work-related injuries, and the impact could be different depending on gender. PMID:29160849

Forms of work organization and associations with shoulder disorders: Results from a French working population.

PubMed

Bodin, Julie; Garlantézec, Ronan; Costet, Nathalie; Descatha, Alexis; Fouquet, Natacha; Caroly, Sandrine; Roquelaure, Yves

2017-03-01

The aim of this study was to identify forms of work organization in a French region and to study associations with the occurrence of symptomatic and clinically diagnosed shoulder disorders in workers. Workers were randomly included in this cross-sectional study from 2002 to 2005. Sixteen organizational variables were assessed by a self-administered questionnaire: i.e. shift work, job rotation, repetitiveness of tasks, paced work/automatic rate, work pace dependent on quantified targets, permanent controls or surveillance, colleagues' work and customer demand, and eight variables measuring decision latitude. Five forms of work organization were identified using hierarchical cluster analysis (HCA) of variables and HCA of workers: low decision latitude with pace constraints, medium decision latitude with pace constraints, low decision latitude with low pace constraints, high decision latitude with pace constraints and high decision latitude with low pace constraints. There were significant associations between forms of work organization and symptomatic and clinically-diagnosed shoulder disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

The effect of shift rotation on variations of cortisol, fatigue and sleep in sound engineers.

PubMed

Vangelova, Katia

2008-10-01

The aim was to study the effect of rotation direction on the time-of-day variations of cortisol, fatigue and sleep in sound engineers broadcasting in a life show. The salivary cortisol and ratings of stress, sleepiness and fatigue were followed at three hour intervals in 25 sound engineers: 13 working very fast forward-rotating shifts and 12 working very fast backward-rotating shifts. Cortisol was assessed with radioimmunological kits. The participants reported for stress symptoms and filled sleep diary. Cortisol retained the typical diurnal pattern. The rotation direction interacted with the shift significantly and as a result higher cortisol values during the morning and night shifts in the backward rotating group were found as well as worse quality of sleep. Higher salivary cortisol during morning and night shifts and worse quality of sleep in engineers working very fast backward-rotating shifts may be an indication for insufficient recovery.

Evaluation of the impact of shiftwork and chronotype on the workers of the imprint and cutting/welding sectors of a flexible packaging manufacturer.

PubMed

de M Guimarães, L B; Pessa, S L R; Biguelini, C

2012-01-01

This article presents a study on the impact of shiftwork and chronotype on the perception of the work conditions, workload and adjustment to shiftwork by the workers of two sectors of a flexible packaging manufacturer, which operates in three fixed shifts. The workers are allocated in one of the shifts (morning, evening and night shifts) without evaluation of their chronotype and/or social needs. The workers' evaluation of the shift system and their work show that they prefer a fixed shift and to work in a shift compatible with their chronotype. The workers with chonotype uncompatible with the shift time tend to be less satisfied with the work conditions and content and feel more discomfort/pain.

Subjective alertness and sleep quality in connection with permanent 12-hour day and night shifts.

PubMed

Gillberg, M

1998-01-01

The aim of this study was to compare permanent 12-hour day and night shifts (shift change over times at 0500 and 1700) in a shift system with 3 work periods followed by 4 free days. Sleep diaries were collected after main periods of sleep, and sleepiness ratings [Karolinska sleepiness scale (KSS)] were obtained 4 times during the last free day and also during the following 3 workshifts. Eighteen to twenty night workers and 8-10 day workers (depending on the instrument) participated. The day workers were significantly sleepier during their workdays. Times for going to bed and for rising differed between the groups. The amount of sleep per week did not differ between groups, but the pattern across days did in that the day workers had a short sleep (5 hours) before the first day and 6 hours of sleep after the other two. Night workers slept long (9 hours) before the first shift and had 6.5-hour sleep periods after the other shifts. During free time the day workers slept around 9 hours and the night workers around 8 hours. Sleep quality and ease of awakening showed no group differences in overall levels, but the day workers had difficulties awakening before their shifts. The night workers had little variation in sleep quality or difficulties awakening. The suggested explanation for the greater sleepiness and difficulties awakening among the day workers was the early start of the shift and the difficulties the workers had with phase advancing their sleep-wake rhythm.

The Risk of Developing Diabetes in Association With Long Working Hours Differs by Shift Work Schedules

PubMed Central

Bannai, Akira; Yoshioka, Eiji; Saijo, Yasuaki; Sasaki, Sachiko; Kishi, Reiko; Tamakoshi, Akiko

2016-01-01

Background The impact of long working hours on diabetes is controversial; however, shift work is known to increase the risk of diabetes. This study aimed to investigate the association between long working hours and diabetes among civil servants in Japan separately by shift work schedules. Methods A prospective cohort study was conducted from April 2003 to March 2009. A total of 3195 men aged ≥35 years who underwent an annual health checkup at baseline were analyzed by shift work schedules (2371 non-shift workers and 824 shift workers). Self-reported working hours were categorized as 35–44 and ≥45 hours per week. The incidence of diabetes was confirmed by fasting plasma glucose concentration ≥126 mg/dL and/or self-reported medical diagnosis of diabetes at the annual checkup. A Cox proportional model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for developing diabetes associated with long working hours. Results The median follow-up period of non-shift and shift workers was 5.0 and 4.9 years, respectively. During this period, 138 non-shift workers and 46 shift workers developed diabetes. A decreased HR was found among non-shift workers working ≥45 hours per week (HR 0.84; 95% CI, 0.57–1.24); however, shift workers working ≥45 hours per week had a significantly increased risk of diabetes (HR 2.43; 95% CI, 1.21–5.10) compared with those working 35–44 hours per week. An analysis restricted to non-clerical workers also showed similar results. Conclusions The risk of diabetes associated with long working hours differed by shift work schedules. PMID:27001115

The Risk of Developing Diabetes in Association With Long Working Hours Differs by Shift Work Schedules.

PubMed

Bannai, Akira; Yoshioka, Eiji; Saijo, Yasuaki; Sasaki, Sachiko; Kishi, Reiko; Tamakoshi, Akiko

2016-09-05

The impact of long working hours on diabetes is controversial; however, shift work is known to increase the risk of diabetes. This study aimed to investigate the association between long working hours and diabetes among civil servants in Japan separately by shift work schedules. A prospective cohort study was conducted from April 2003 to March 2009. A total of 3195 men aged ≥35 years who underwent an annual health checkup at baseline were analyzed by shift work schedules (2371 non-shift workers and 824 shift workers). Self-reported working hours were categorized as 35-44 and ≥45 hours per week. The incidence of diabetes was confirmed by fasting plasma glucose concentration ≥126 mg/dL and/or self-reported medical diagnosis of diabetes at the annual checkup. A Cox proportional model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for developing diabetes associated with long working hours. The median follow-up period of non-shift and shift workers was 5.0 and 4.9 years, respectively. During this period, 138 non-shift workers and 46 shift workers developed diabetes. A decreased HR was found among non-shift workers working ≥45 hours per week (HR 0.84; 95% CI, 0.57-1.24); however, shift workers working ≥45 hours per week had a significantly increased risk of diabetes (HR 2.43; 95% CI, 1.21-5.10) compared with those working 35-44 hours per week. An analysis restricted to non-clerical workers also showed similar results. The risk of diabetes associated with long working hours differed by shift work schedules.

Sleep loss and circadian disruption in shift work: health burden and management.

PubMed

Rajaratnam, Shantha M W; Howard, Mark E; Grunstein, Ronald R

2013-10-21

About 1.5 million Australians are shift workers. Shift work is associated with adverse health, safety and performance outcomes. Circadian rhythm misalignment, inadequate and poor-quality sleep, and sleep disorders such as sleep apnoea, insomnia and shift work disorder (excessive sleepiness and/or insomnia temporally associated with the work schedule) contribute to these associations. Falling asleep at work at least once a week occurs in 32%-36% of shift workers. Risk of occupational accidents is at least 60% higher for non-day shift workers. Shift workers also have higher rates of cardiometabolic diseases and mood disturbances. Road and workplace accidents related to excessive sleepiness, to which shift work is a significant contributor, are estimated to cost $71-$93 billion per annum in the United States. There is growing evidence that understanding the interindividual variability in sleep-wake responses to shift work will help detect and manage workers vulnerable to the health consequences of shift work. A range of approaches can be used to enhance alertness in shift workers, including screening and treating sleep disorders, melatonin treatment to promote sleep during the daytime, and avoidance of inappropriate use of sedatives and wakefulness-promoters such as modafinil and caffeine. Short naps, which minimise sleep inertia, are generally effective. Shifting the circadian pacemaker with appropriately timed melatonin and/or bright light may be used to facilitate adjustment to a shift work schedule in some situations, such as a long sequence of night work. It is important to manage the health risk of shift workers by minimising vascular risk factors through dietary and other lifestyle approaches.

Shift Work Is Associated with Metabolic Syndrome in Young Female Korean Workers.

PubMed

Yu, Kyoung Hwa; Yi, Yu Hyeon; Kim, Yun Jin; Cho, Byung Mann; Lee, Sang Yeoup; Lee, Jeong Gyu; Jeong, Dong Wook; Ji, So Yeon

2017-03-01

Shift work is associated with health problems, including metabolic syndrome. This study investigated the association between shift work and metabolic syndrome in young workers. A total of 3,317 subjects aged 20-40 years enrolled in the 2011-2012 Korean National Health and Nutrition Examination Survey were divided into shift and day workers. We conducted a cross-sectional study and calculated odds ratios using multivariate logistic regression analysis in order to examine the association between shift work and metabolic syndrome. The prevalence of metabolic syndrome was 14.3% and 7.1% among male and female shift workers, respectively. After adjusting for confounding factors, shift work was associated with metabolic syndrome in female workers (odds ratio, 2.53; 95% confidence interval, 1.12 to 5.70). Shift work was associated with metabolic syndrome in young women. Timely efforts are necessary to manage metabolic syndrome in the workplace.

Relationship between thyroid stimulating hormone and night shift work.

PubMed

Moon, So-Hyun; Lee, Bum-Joon; Kim, Seong-Jin; Kim, Hwan-Cheol

2016-01-01

Night shift work has well-known adverse effects on health. However, few studies have investigated the relationship between thyroid diseases and night shift work. This study aimed to examine night shift workers and their changes in thyroid stimulating hormones (TSH) levels over time. Medical check-up data (2011-2015) were obtained from 967 female workers at a university hospital in Incheon, Korea. Data regarding TSH levels were extracted from the records, and 2015 was used as a reference point to determine night shift work status. The relationships between TSH levels and night shift work in each year were analyzed using the general linear model (GLM). The generalized estimating equation (GEE) was used to evaluate the repeated measurements over the 5-year period. The GEE analysis revealed that from 2011 to 2015, night shift workers had TSH levels that were 0.303 mIU/L higher than the levels of non-night shift workers (95 % CI: 0.087-0.519 mIU/L, p  = 0.006) after adjusting for age and department. When we used TSH levels of 4.5 ≥ mIU/L to identify subclinical hypothyroidism, night shift workers exhibited a 1.399 fold higher risk of subclinical hypothyroidism (95 % CI: 1.050-1.863, p  = 0.022), compared to their non-night shift counterparts. This result of this study suggests that night shift workers may have an increased risk of thyroid diseases, compared to non-night shift workers.

Relationship of night and shift work with weight change and lifestyle behaviors.

PubMed

Bekkers, Marga B M; Koppes, Lando L J; Rodenburg, Wendy; van Steeg, Harry; Proper, Karin I

2015-04-01

To prospectively study the association of night and shift work with weight change and lifestyle behaviors. Workers participating in the Netherlands Working Conditions Cohort Study (2008 and 2009) (N = 5951) reported night and shift work, weight and height. Groups included stable night or shift work, from day work to night or shift work, from night or shift work to day work, and no night or shift work in 2008 and 2009. Regression analyses were used to study association changes in night and shift work with weight change and changes in lifestyle behaviors. A larger weight change was seen in normal-weight workers changing from day to shift work (β = 0.93%; 95% confidence interval, 0.01 to 1.85) compared with stable no shift workers. No further associations of night and shift work with weight change were observed, neither in normal-weight, overweight, and obese workers. Despite the fact that starting night or shift work is associated with some unhealthy lifestyle habits, this study did not confirm a positive association of night and shift work with weight change over 1 year, except for normal-weight workers moving from day to shift work.

Prevalence of permanent hearing threshold shift among workers of Indian iron and steel small and medium enterprises: a study.

PubMed

Singh, Lakhwinder Pal; Bhardwaj, Arvind; Kumar, Deepak Kishore

2012-01-01

Occupational noise exposure and noise-induced hearing loss (NIHL) have been recognized as a problem among workers in Indian industries. The major industries in India are based on manufacturing. There are appreciable numbers of casting and forging units spread across the country. The objective of this study is to determine the prevalence of permanent hearing threshold shift among the workers engaged in Indian iron and steel small and medium enterprises (SMEs) and compared with control group subjects. As a part of hearing protection intervention, audiometric tests were conducted at low (250-1000 Hz), medium (1500-3000 Hz), and high (4000-8000 Hz) frequencies. The occurrence of hearing loss was determined based on hearing threshold levels with a low fence of 25 dB. Comparisons were made for hearing threshold at different frequencies between the exposed and control groups using Student's t test. ANOVA was used for the comparison of hearing threshold dB at different frequencies among occupation and year of experience. A P value <0.05 was considered as statistically significant. All data were presented as mean value (SD). Over 90% of workers engaged in various processes of casting and forging industry showed hearing loss in the noise-sensitive medium and higher frequencies. Occupation was significantly associated with NIHL, and hearing loss was particularly high among the workers of forging section. The analyses revealed a higher prevalence of significant hearing loss among the forging workers compared to the workers associated with other activities. The study shows alarming signals of NIHL, especially in forging workers. The occupational exposure to noise could be minimized by efficient control measures through engineering controls, administrative controls, and the use of personal protective devices. Applications of engineering and/or administrative controls are frequently not feasible in the developing countries for technical and financial reasons. A complete hearing conservation programme, including training, audiometry, job rotation, and the use of hearing protection devices, is the most feasible method for the protection of industrial workers from prevailing noise in workplace environments in the developing countries.

Who is sleepier on the night shift? The influence of bio-psycho-social factors on subjective sleepiness of female nurses during the night shift.

PubMed

Zion, Nataly; Drach-Zahavy, Anat; Shochat, Tamar

2018-07-01

Sleepiness is a common complaint during the night shift and may impair performance. The current study aims to identify bio-psycho-social factors associated with subjective sleepiness during the night shift. Ninety-two female nurses working rotating shifts completed a sociodemographic questionnaire, the Munich ChronoType Questionaire for shift workers, the Pittsburg Sleep Quality Index, and the Pre-sleep Arousal Scale. Subjective sleepiness was measured hourly during two night shifts using the Karolinska Sleepiness Scale, and activity monitors assessed sleep duration 24-h before each shift. Findings showed that increased sleepiness was associated with increased age in nurses with early chronotypes and with more children. High cognitive pre-sleep arousal, but not sleep, was associated with increased sleepiness, especially in late chronotypes. The impact of bio-psycho-social factors on night shift sleepiness is complex, and depends on mutual interactions between these factors. Nurses most prone to increased sleepiness must develop personal strategies for maintaining vigilance on the night shift. Practitioner Summary: This study aims to identify bio-psycho-social factors associated with subjective sleepiness of female nurses during the night shift. Increasing sleepiness was associated with increased age in nurses with early chronotypes and with more children. Increased cognitive pre-sleep arousal, but not sleep, was associated with increased sleepiness, especially in late chronotypes.

Night shift work and hormone levels in women.

PubMed

Davis, Scott; Mirick, Dana K; Chen, Chu; Stanczyk, Frank Z

2012-04-01

Night shift work may disrupt the normal nocturnal rise in melatonin, resulting in increased breast cancer risk, possibly through increased reproductive hormone levels. We investigated whether night shift work is associated with decreased levels of urinary 6-sulfatoxymelatonin, the primary metabolite of melatonin, and increased urinary reproductive hormone levels. Participants were 172 night shift and 151 day shift-working nurses, aged 20-49 years, with regular menstrual cycles. Urine samples were collected throughout work and sleep periods and assayed for 6-sulfatoxymelatonin, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estrone conjugate (E1C). 6-Sulfatoxymelatonin levels were 62% lower and FSH and LH were 62% and 58% higher, respectively, in night shift-working women during daytime sleep than in day shift-working women during nighttime sleep (P ≤ 0.0001). Nighttime sleep on off-nights was associated with 42% lower 6-sulfatoxymelatonin levels among the night shift workers, relative to the day shift workers (P < 0.0001); no significant differences in LH or FSH were observed. 6-Sulfatoxymelatonin levels during night work were approximately 69% lower and FSH and LH were 35% and 38% higher, compared with day shift workers during nighttime sleep. No differences in E1C levels between night and day shift workers were observed. Within night shift workers, 6-sulfatoxymelatonin levels were lower and reproductive hormone levels were higher during daytime sleep and nighttime work, relative to nighttime sleep (P < 0.05). These results indicate that night shift workers have substantially reduced 6-sulfatoxymelatonin levels during night work and daytime sleep and that levels remain low even when a night shift worker sleeps at night. Shift work could be an important risk factor for many other cancers in addition to breast cancer. ©2012 AACR.

Experience and limited lighting may affect sleepiness of tunnel workers

PubMed Central

2014-01-01

Background Working on shifts, especially on a night shift, influences the endogenous sleep regulation system leading to diminished sleep time and increased somnolence. We attempted to evaluate the impact of shifts on sleepiness and correlate the sleepiness score to the experience in a shift schedule. Materials and methods This cross-sectional study consists of 42 male and 2 female workers involved in a tunnel construction. They underwent spirometry, pulse oximetry and were asked to complete the Epworth Sleepiness Scale questionnaire. Results Statistical analysis revealed that workers of lower Epworth had a mean age of 43.6 years, compared to the mean age of 36.4 years of workers with higher Epworth. Furthermore, workers of lower Epworth were characterized by a mean number of shift years equal to 14.8, while those of higher Epworth possessed a mean number of shift years equal to 8. The shift schedule did not reveal any statistically significant correlation. Conclusions Workers employed for a longer time had diminished sleepiness. However, there is no relationship between night shifts and sleepiness, possibly because of exposure to artificial lighting in the construction site. PMID:24993796

Experience and limited lighting may affect sleepiness of tunnel workers.

PubMed

Lykouras, Dimosthenis; Karkoulias, Kiriakos; Patouchas, Dimitrios; Lakoumentas, John; Sampsonas, Fotis; Tranou, Magdalini-Konstantina; Faliagka, Evanthia; Tsakalidis, Athanasios; Spiropoulos, Kostas

2014-07-03

Working on shifts, especially on a night shift, influences the endogenous sleep regulation system leading to diminished sleep time and increased somnolence. We attempted to evaluate the impact of shifts on sleepiness and correlate the sleepiness score to the experience in a shift schedule. This cross-sectional study consists of 42 male and 2 female workers involved in a tunnel construction. They underwent spirometry, pulse oximetry and were asked to complete the Epworth Sleepiness Scale questionnaire. Statistical analysis revealed that workers of lower Epworth had a mean age of 43.6 years, compared to the mean age of 36.4 years of workers with higher Epworth. Furthermore, workers of lower Epworth were characterized by a mean number of shift years equal to 14.8, while those of higher Epworth possessed a mean number of shift years equal to 8. The shift schedule did not reveal any statistically significant correlation. Workers employed for a longer time had diminished sleepiness. However, there is no relationship between night shifts and sleepiness, possibly because of exposure to artificial lighting in the construction site.

Roles of safety climate and shift work on perceived injury risk: a multi-level analysis.

PubMed

Huang, Yueng-Hsiang; Chen, Jiu-Chiuan; DeArmond, Sarah; Cigularov, Konstantin; Chen, Peter Y

2007-11-01

This study evaluated the relationship between employees' work shift (i.e., day shift versus night shift) and perceptions of injury risk, and how the relationship is affected by company level safety climate and injury frequency. The results showed that night shift workers perceived a higher level of injury risk compared to day shift workers. Both company level safety climate and injury frequency played critical roles in predicting individual perceived work injury risk. Perception of injury risk of night shift workers was significantly lower when they perceived high-level rather than low-level safety climate. However, this pattern was not noticeable for day shift workers. These findings highlighted the importance of considering company level factors when attempting to understand the differences between day shift and night shift work on an individual's perception of injury risk.

[Relationship between shift work and overweight/obesity in male steel workers].

PubMed

Xiao, M Y; Wang, Z Y; Fan, H M; Che, C L; Lu, Y; Cong, L X; Gao, X J; Liu, Y J; Yuan, J X; Li, X M; Hu, B; Chen, Y P

2016-11-10

Objective: To investigate the relationship between shift work and overweight/obesity in male steel workers. Methods: A questionnaire survey was conducted among the male steel workers selected during health examination in Tangshan Steel Company from March 2015 to March 2016. The relationship between shift work and overweight/obesity in the male steel workers were analyzed by using logistic regression model and restricted cubic splinemodel. Results: A total of 7 262 male steel workers were surveyed, the overall prevalence of overweight/obesitywas 64.5% (4 686/7 262), the overweight rate was 34.3% and the obesity rate was 30.2%, respectively. After adjusting for age, educational level and average family income level per month by multivariable logistic regression analysis, shift work was associated with overweight/obesity and obesity in the male steel workers. The OR was 1.19(95% CI : 1.05-1.35) and 1.15(95% CI : 1.00-1.32). Restricted cubic spline model analysis showed that the relationship between shift work years and overweight/obesity in the male steel workers was a nonlinear dose response one (nonlinear test χ 2 =7.43, P <0.05). Restricted cubic spline model analysis showed that the relationship between shift work years and obesity in the male steel workers was a nonlinear dose response one (nonlinear test χ 2 =10.48, P <0.05). Conclusion: Shift work was associated with overweight and obesity in the male steel workers, and shift work years and overweight/obesity had a nonlinear relationship.

Evaluation of the effect of shift work on serum cholesterol and triglyceride levels.

PubMed

Akbari, Hamed; Mirzaei, Ramazan; Nasrabadi, Tahereh; Gholami-Fesharaki, Mohammad

2015-01-01

Working outside daylight hours (7 am to 7 pm) is called shift work. Shift work is a common practice in many industries and factories such as steel industries, petroleum industries, power plants, and in some services such as medicine and nursing and police forces, in which professionals provide services during day and night. Considering the contradictory reports of different studies, we decided to evaluate the effect of shift work on cholesterol and triglyceride (TG) levels through a historical cohort on steel industry workers. This retrospective cohort study was performed on all the staff of Isfahan's Mobarakeh Steel Company between years 2002 and 2011. There were 5773 participants in this study. Data were collected from the medical records of the staff using the census method. For analysis of data, generalized estimating equation (GEE) regression was used. The results showed a significant difference in cholesterol levels between shift workers and day workers on the first observation (P < 0.001), yet no such difference was observed for TG (P = 0.853). Moreover, the results showed that the variables of age, work experience and BMI were not similar between shift workers and day workers. Therefore, to remove the effect of such variables, we used GEE regression. Despite the borderline difference of cholesterol between regular shift workers and day workers, this correlation was not statistically significant (P = 0.051). The results for TG also showed no correlation with shift work. According to the findings of this study, there is no relationship between shift work and changes in serum TG and cholesterol. The lack of relationship can be due to shift plans for shift workers, nutrition, or the "Healthy Heart project" at Isfahan Mobarakeh Steel Company.

Do working environment interventions reach shift workers?

PubMed

Nabe-Nielsen, Kirsten; Jørgensen, Marie Birk; Garde, Anne Helene; Clausen, Thomas

2016-01-01

Shift workers are exposed to more physical and psychosocial stressors in the working environment as compared to day workers. Despite the need for targeted prevention, it is likely that workplace interventions less frequently reach shift workers. The aim was therefore to investigate whether the reach of workplace interventions varied between shift workers and day workers and whether such differences could be explained by the quality of leadership exhibited at different times of the day. We used questionnaire data from 5361 female care workers in the Danish eldercare sector. The questions concerned usual working hours, quality of leadership, and self-reported implementation of workplace activities aimed at stress reduction, reorganization of the working hours, and participation in improvements of working procedures or qualifications. Compared with day workers, shift workers were less likely to be reached by workplace interventions. For example, night workers less frequently reported that they had got more flexibility (OR 0.5; 95 % CI 0.3-0.7) or that they had participated in improvements of the working procedures (OR 0.6; 95 % CI 0.5-0.8). Quality of leadership to some extent explained the lack of reach of interventions especially among fixed evening workers. In the light of the evidence of shift workers' stressful working conditions, we suggest that future studies focus on the generalizability of results of the present study and on how to reach this group and meet their needs when designing and implementing workplace interventions.

Heart rate variability in male shift workers in automobile manufacturing factories in South Korea.

PubMed

Lee, Sangyoon; Kim, Ho; Kim, Dae-Hwan; Yum, Myunggul; Son, Mia

2015-10-01

The aim of this study was to determine the effect of circadian rhythm disruption on cardiovascular autonomic regulation by examining potential differences in heart rate variability (HRV) between day- and night-shift workers. The study population consisted of 162 workers who worked both day and night shifts in two automobile manufacturing companies who underwent ambulatory 24-h electrocardiogram recording and completed questionnaires and sleep diaries. Both time and frequency domain indices of HRV were compared. HRV parameters (mean RR, SDNN, RMSSD, pNN50, TP, HF, LF, LF/HF ratio) reflecting sympathetic and parasympathetic modulation varied less with activity in night-shift workers. Circadian rhythm-mediated changes in autonomic regulation of the cardiovascular system were blunted in night-shift workers, which could contribute to an increased risk for cardiovascular disease in overnight workers.

Sorting photons of different rotational Doppler shifts (RDS) by orbital angular momentum of single-photon with spin-orbit-RDS entanglement.

PubMed

Chen, Lixiang; She, Weilong

2008-09-15

We demonstrate that single photons from a rotating q-plate exhibit an entanglement in three degrees of freedom of spin, orbital angular momentum, and the rotational Doppler shift (RDS) due to the nonconservation of total spin and orbital angular momenta. We find that the rotational Doppler shift deltaomega = Omega((delta)s + deltal) , where s, l and Omega are quantum numbers of spin, orbital angular momentum, and rotating velocity of the q-plate, respectively. Of interest is that the rotational Doppler shift directly reflects the rotational symmetry of q-plates and can be also expressed as deltaomega = (Omega)n , where n = 2(q-1) denotes the fold number of rotational symmetry. Besides, based on this single-photon spin-orbit-RDS entanglement, we propose an experimental scheme to sort photons of different frequency shifts according to individual orbital angular momentum.

Shift scheduling model considering workload and worker’s preference for security department

NASA Astrophysics Data System (ADS)

Herawati, A.; Yuniartha, D. R.; Purnama, I. L. I.; Dewi, LT

2018-04-01

Security department operates for 24 hours and applies shift scheduling to organize its workers as well as in hotel industry. This research has been conducted to develop shift scheduling model considering the workers physical workload using rating of perceived exertion (RPE) Borg’s Scale and workers’ preference to accommodate schedule flexibility. The mathematic model is developed in integer linear programming and results optimal solution for simple problem. Resulting shift schedule of the developed model has equally distribution shift allocation among workers to balance the physical workload and give flexibility for workers in working hours arrangement.

Physical occupational exposures and health expectancies in a French occupational cohort

PubMed Central

Head, Jenny; Stenholm, Sari; Singh Chungkham, Holendro; Goldberg, Marcel; Zins, Marie

2017-01-01

Objectives To examine the relationships of strenuous and hazardous working conditions and rotating shifts that involve night working with life expectancy in good perceived health and life expectancy without chronic disease. Methods The sample contained male gas and electricity workers from the French GAZEL cohort (n=13 393). Six measures of physical working conditions were examined: Self-reports from 1989 and 1990 of ergonomic strain, physical danger, rotating shifts that involve night working and perceived physical strain; company records of workplace injuries and a job-exposure matrix of chemical exposures. Partial healthy life expectancies (age 50–75) relating to (1) self-rated health and (2) chronic health conditions, obtained from annual questionnaires (1989–2014) and company records, were estimated using multistate life tables. The analyses were adjusted for social class and occupational grade. Results Participants with physically strenuous jobs and who had experienced industrial injuries had shorter partial life expectancy. More physically demanding and dangerous work was associated with fewer years of life spent in good self-rated health and without chronic conditions, with the exception of shift work including nights, where the gradient was reversed. Conclusions Strenuous and hazardous work may contribute to lost years of good health in later life, which has implications for individuals' quality of life as well as healthcare use and labour market participation. PMID:27655775

Day and night shift schedules are associated with lower sleep quality in Evening-types.

PubMed

Martin, Jeanne Sophie; Laberge, Luc; Sasseville, Alexandre; Bérubé, Marilie; Alain, Samuel; Houle, Jérôme; Hébert, Marc

2015-06-01

Eveningness has been suggested as a facilitating factor in adaptation to shift work, with several studies reporting evening chronotypes (E-types) as better sleepers when on night shifts. Conversely, eveningness has been associated with more sleep complaints during day shifts. However, sleep during day shifts has received limited attention in previous studies assessing chronotypes in shift workers. Environmental light exposure has also been reported to differ between chronotypes in day workers. Activity is also known to provide temporal input to the circadian clock. Therefore, the aim of this study was to compare objective sleep, light exposure and activity levels between chronotypes, both during the night and day shifts. Thirty-nine patrol police patrol officers working on a fast rotating shift schedule (mean age ± SD: 28.9 ± 3.2 yrs; 28 males) participated in this study. All subjects completed the Morningness-Eveningness Questionnaire (MEQ). Sleep and activity were monitored with actigraphy (Actiwatch-L; Mini-Mitter/Respironics, Bend, OR) for four consecutive night shifts and four consecutive day shifts (night work schedule: 00:00 h-07:00 h; day work schedule: 07:00 h-15:00 h). Sleep and activity parameters were calculated with Actiware software. MEQ scores ranged from 26 to 56; no subject was categorized as Morning-type. E-types (n = 13) showed significantly lower sleep efficiency, longer snooze time and spent more time awake after sleep onset than Intermediate-types (I-types, n = 26) for both the night and day shifts. E-types also exhibited shorter and more numerous sleep bouts. Furthermore, when napping was taken into account, E-types had shorter total sleep duration than I-types during the day shifts. E-types were more active during the first hours of their night shift when compared to I-types. Also, all participants spent more time active and had higher amount of activity per minute during day shifts when compared to night shifts. No difference was found regarding light exposure between chronotypes. In conclusion, sleep parameters revealed poorer sleep quality in E-types for both the night and day shifts. These differences could not be explained by sleep opportunity, light exposure or activity levels. This study challenges the notion that E-types adapt better to night shifts. Further studies must verify whether E-types exhibit lower sleep quality than Morning-types.

Correlates to sleepiness on night shift among male workers engaged in three-shift work in a chemical plant: its association with sleep practice and job stress.

PubMed

Kageyama, Takayuki; Kobayashi, Toshio; Abe-Gotoh, Ayano

2011-01-01

The purpose of this study was to examine the correlation of sleepiness during night shift (SNS) in male shiftworkers with nonpharmacological self-management (nPSM) practices to facilitate good day sleep, and also with job stress. Sleepiness on the job and possible correlates to SNS among 157 male shiftworkers in a rotating three-shift schedule at a chemical plant were cross-sectionally investigated using a self-administered questionnaire. Multivariate analyses revealed that SNS was positively associated with drinking alcoholic beverages before day sleep, but inversely associated with subjective health status, being of the evening type, abstaining from caffeine before day sleep, having a bath before day sleep, job control, reward from work, feeling suited to the job, and support from colleagues. SNS correlated with certain nPSM practices and also with possible modifiers of job stress. These findings provide clues to developing countermeasures against SNS among shiftworkers. The effects of nPSM practices and job stress management on their day sleep and SNS should be examined in detail.

A primary shift rotation nurse scheduling using zero-one linear goal programming.

PubMed

Huarng, F

1999-01-01

In this study, the author discusses the effect of nurse shift schedules on circadian rhythm and some important ergonomics criteria. The author also reviews and compares different nurse shift scheduling methods via the criteria of flexibility, fairness, continuity in shift assignments, nurses' preferences, and ergonomics principles. In this article, a primary shift rotation system is proposed to provide better continuity in shift assignments to satisfy nurses' preferences. The primary shift rotation system is modeled as a zero-one linear goal programming (LGP) problem. To generate the shift assignment for a unit with 13 nurses, the zero-one LGP model takes less than 3 minutes on average, whereas the head nurses spend approximately 2 to 3 hours on shift scheduling. This study reports the process of implementing the primary shift rotation system.

The relationship between shift work and mental health among electronics workers in South Korea: A cross-sectional study.

PubMed

Kang, Mo-Yeol; Kwon, Ho-Jang; Choi, Kyung-Hwa; Kang, Chung-Won; Kim, Hyunjoo

2017-01-01

To determine the relationship between shift work and mental health, particularly insomnia, depression, and suicidal ideation, among electronics production workers. A survey was conducted with 14,226 workers from an electronics manufacturer in South Korea. After excluding 112 individuals with incomplete responses, 14,114 respondents were analyzed. As part of a larger project, we collected data on respondents' general characteristics, work-related characteristics, and health status; however, in this study, we focused on the data related to shift work and mental health. Insomnia, depression, and suicidal ideation were set as dependent variables and working schedule as set as the independent variable. We performed multiple logistic regression analysis with daytime workers as the reference group. The model was adjusted for age, gender, body mass index, workplace, educational level, and marital status with or without children under 6 years of age. Relative to daytime workers, shift workers had 2.35, 1.23, and 1.17 greater odds of insomnia, depression, and suicidal ideation, respectively. Within the shift worker group, we found that the odds of depression and suicidal ideation increased dramatically when respondents had insomnia. The ORs for depression and suicidal ideation were 4.899 and 7.934, respectively. Our findings suggest that shift work is related to an increased risk of mental health problems in production workers, and the sleep disturbance related with shift work is a central mechanism for this relationship. Since these results suggest that proactive management of sleep problems might attenuate their detrimental effects on shift worker's mental health.

Food and nutrient intake among workers with different shift systems.

PubMed

Hemiö, Katri; Puttonen, Sampsa; Viitasalo, Katriina; Härmä, Mikko; Peltonen, Markku; Lindström, Jaana

2015-07-01

Over 20% of employees in Europe work in shifts. Shift work increases the risk for chronic diseases, but a healthy lifestyle may attenuate the adverse effect of shift work. The aim of this study was to explore food and nutrient intake differences between working time groups. The participants were 1478 employees (55% of men) of an airline divided into three working time groups: day work (n=608), shift work without in-flight work (n=541) and in-flight work (n=329). Measures included laboratory tests, physical measurements, a questionnaire, and food and nutrient intake estimations by a validated 16-item food intake questionnaire. Shift working men were less likely to consume vegetables (p<0.001) and fruits (p=0.049) daily than male day and in-flight workers. In women, energy intake from saturated fat was higher among shift workers compared with day workers (12.6 vs 12.2 E%, p=0.023). In older female participants, energy intake from fat and saturated fat was higher in the shift work and in-flight work groups than in the day work group (p<0.001). In this study, shift work and working environment were associated with dietary habits, and this association was not explained by other characteristics such as workers' educational level. Shift workers' increased risk for chronic diseases should be taken into account and lifestyle counselling including advice in nutrition should be incorporated in routine occupational healthcare of shift workers. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Obesity and shift work: chronobiological aspects.

PubMed

Antunes, L C; Levandovski, R; Dantas, G; Caumo, W; Hidalgo, M P

2010-06-01

The present review has the objective of summarising chronobiological aspects of shift work and obesity. There was a systematic search in PubMed databases, using the following descriptors: shift work; obesity; biological clock. Shift work is extremely frequent in several services and industries, in order to systematise the needs for flexibility of the workforce, necessary to optimise productivity and business competitiveness. In developing countries, this population represents a considerable contingent workforce. Recently, studies showed that overweight and obesity are more prevalent in shift workers than day workers. In addition, the literature shows that shift workers seem to gain weight more often than those workers submitted to a usual work day. In conclusion, there is considerable epidemiological evidence that shift work is associated with increased risk for obesity, diabetes and CVD, perhaps as a result of physiological maladaptation to chronically sleeping and eating at abnormal circadian times. The impact of shift work on metabolism supports a possible pathway to the development of obesity and its co-morbities. The present review demonstrated the adverse cardiometabolic implications of circadian misalignment, as occurs chronically with shift workers.

Healthy Diet And Reduction Of Chronic Disease Risks Of Night Shift Workers.

PubMed

Ferri, Giovanni M; Cavone, Domenica; Intranuovo, Graziana; Macinagrossa, Linda

2017-07-20

The large increase in epidemiological studies on night shift work is due to the important effects of night shift work on workers' health and psychophysical wellbeing. The short-term effects-insomnia, difficulties in managing work and private life, lower work performance, and more work and extra-work accidents-are easily studied. However, there are several long-term effects that are difficult to study because of the need for detailed exposure assessment and the long latency periods of these diseases. The aim was to collect epidemiologic evidence of diseases in night shift workers, describing their biological pathways and a set of dietary guidelines. This is a review on diet and health effects in night shift workers. Significant increases in the rate ratios and hazard ratios of different diseases were associated with modified eating behaviours and poor eating habits among night shift workers. Night shift work is a risk factor for disruption of the circadian rhythms and for some genetic deregulation because it produces the inversion of the sleep/wake cycle and modifies the alternation between activity and rest. A healthy diet and improved dietary practices, together with other factors, can reduce shift workers' chronic disease risk. The literature showed the importance of eating behaviour in order to prevent diseases in these workers; therefore, educational programmes are necessary to encourage several important lifestyle changes. The target of our future research will be the role of food components in some dietetic habits for the prevention of disease in night shift workers. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Self-Reported Recovery from 2-Week 12-Hour Shift Work Schedules: A 14-Day Follow-Up.

PubMed

Merkus, Suzanne L; Holte, Kari Anne; Huysmans, Maaike A; van de Ven, Peter M; van Mechelen, Willem; van der Beek, Allard J

2015-09-01

Recovery from fatigue is important in maintaining night workers' health. This study compared the course of self-reported recovery after 2-week 12-hour schedules consisting of either night shifts or swing shifts (i.e., 7 night shifts followed by 7 day shifts) to such schedules consisting of only day work. Sixty-one male offshore employees-20 night workers, 16 swing shift workers, and 25 day workers-rated six questions on fatigue (sleep quality, feeling rested, physical and mental fatigue, and energy levels; scale 1-11) for 14 days after an offshore tour. After the two night-work schedules, differences on the 1(st) day (main effects) and differences during the follow-up (interaction effects) were compared to day work with generalized estimating equations analysis. After adjustment for confounders, significant main effects were found for sleep quality for night workers (1.41, 95% confidence interval 1.05-1.89) and swing shift workers (1.42, 95% confidence interval 1.03-1.94) when compared to day workers; their interaction terms were not statistically significant. For the remaining fatigue outcomes, no statistically significant main or interaction effects were found. After 2-week 12-hour night and swing shifts, only the course for sleep quality differed from that of day work. Sleep quality was poorer for night and swing shift workers on the 1(st) day off and remained poorer for the 14-day follow-up. This showed that while working at night had no effect on feeling rested, tiredness, and energy levels, it had a relatively long-lasting effect on sleep quality.

Examining courses of sleep quality and sleepiness in full 2 weeks on/2 weeks off offshore day shift rotations.

PubMed

Riethmeister, V; Bültmann, U; De Boer, M R; Gordijn, M; Brouwer, S

2018-05-16

To better understand sleep quality and sleepiness problems offshore, we examined courses of sleep quality and sleepiness in full 2-weeks on/2-weeks off offshore day shift rotations by comparing pre-offshore (1 week), offshore (2 weeks) and post-offshore (1 week) work periods. A longitudinal observational study was conducted among N=42 offshore workers. Sleep quality was measured subjectively with two daily questions and objectively with actigraphy, measuring: time in bed (TIB), total sleep time (TST), sleep latency (SL) and sleep efficiency percentage (SE%). Sleepiness was measured twice a day (morning and evening) with the Karolinska Sleepiness Scale. Changes in sleep and sleepiness parameters during the pre/post and offshore work periods were investigated using (generalized) linear mixed models. In the pre-offshore work period, courses of SE% significantly decreased (p=.038). During offshore work periods, the courses of evening sleepiness scores significantly increased (p<.001) and significantly decreased during post-offshore work periods (p=.004). During offshore work periods, TIB (p<.001) and TST (p<.001) were significantly shorter, SE% was significantly higher (p=.002), perceived sleep quality was significantly lower (p<.001) and level of rest after wake was significantly worse (p<.001) than during the pre- and post-offshore work periods. Morning sleepiness was significantly higher during offshore work periods (p=.015) and evening sleepiness was significantly higher in the post-offshore work period (p=.005) compared to the other periods. No significant changes in SL were observed. Courses of sleep quality and sleepiness parameters significantly changed during full 2-weeks on/2-weeks off offshore day shift rotation periods. These changes should be considered in offshore fatigue risk management programmes.

Increased and mistimed sex hormone production in night shift workers.

PubMed

Papantoniou, Kyriaki; Pozo, Oscar J; Espinosa, Ana; Marcos, Josep; Castaño-Vinyals, Gemma; Basagaña, Xavier; Juanola Pagès, Elena; Mirabent, Joan; Martín, Jordi; Such Faro, Patricia; Gascó Aparici, Amparo; Middleton, Benita; Skene, Debra J; Kogevinas, Manolis

2015-05-01

Night shift work has been associated with an increased risk for breast and prostate cancer. The effect of circadian disruption on sex steroid production is a possible underlying mechanism, underinvestigated in humans. We have assessed daily rhythms of sex hormones and melatonin in night and day shift workers of both sexes. We recruited 75 night and 42 day workers, ages 22 to 64 years, in different working settings. Participants collected urine samples from all voids over 24 hours on a working day. Urinary concentrations of 16 sex steroid hormones and metabolites (estrogens, progestagens, and androgens) and 6-sulfatoxymelatonin were measured in all samples. Mean levels and peak time of total and individual metabolite production were compared between night and day workers. Night workers had higher levels of total progestagens [geometric mean ratio (GMR) 1.65; 95% confidence intervals (CI), 1.17-2.32] and androgens (GMR: 1.44; 95% CI, 1.03-2.00), compared with day workers, after adjusting for potential confounders. The increased sex hormone levels among night shift workers were not related to the observed suppression of 6-sulfatoxymelatonin. Peak time of androgens was significantly later among night workers, compared with day workers (testosterone: 12:14 hours; 10:06-14:48 vs. 08:35 hours; 06:52-10:46). We found increased levels of progestagens and androgens as well as delayed peak androgen production in night shift workers compared with day workers. The increase and mistiming of sex hormone production may explain part of the increased risk for hormone-related cancers observed in night shift workers. ©2015 American Association for Cancer Research.

Total and cause-specific mortality of U.S. nurses working rotating night shifts.

PubMed

Gu, Fangyi; Han, Jiali; Laden, Francine; Pan, An; Caporaso, Neil E; Stampfer, Meir J; Kawachi, Ichiro; Rexrode, Kathryn M; Willett, Walter C; Hankinson, Susan E; Speizer, Frank E; Schernhammer, Eva S

2015-03-01

Rotating night shift work imposes circadian strain and is linked to the risk of several chronic diseases. To examine associations between rotating night shift work and all-cause; cardiovascular disease (CVD); and cancer mortality in a prospective cohort study of 74,862 registered U.S. nurses from the Nurses' Health Study. Lifetime rotating night shift work (defined as ≥3 nights/month) information was collected in 1988. During 22 years (1988-2010) of follow-up, 14,181 deaths were documented, including 3,062 CVD and 5,413 cancer deaths. Cox proportional hazards models estimated multivariable-adjusted hazard ratios (HRs) and 95% CIs. All-cause and CVD mortality were significantly increased among women with ≥5 years of rotating night shift work, compared to women who never worked night shifts. Specifically, for women with 6-14 and ≥15 years of rotating night shift work, the HRs were 1.11 (95% CI=1.06, 1.17) and 1.11 (95% CI=1.05, 1.18) for all-cause mortality and 1.19 (95% CI=1.07, 1.33) and 1.23 (95% CI=1.09, 1.38) for CVD mortality. There was no significant association between rotating night shift work and all-cancer mortality (HR≥15years=1.08, 95% CI=0.98, 1.19) or mortality of any individual cancer, with the exception of lung cancer (HR≥15years=1.25, 95% CI=1.04, 1.51). Women working rotating night shifts for ≥5 years have a modest increase in all-cause and CVD mortality; those working ≥15 years of rotating night shift work have a modest increase in lung cancer mortality. These results add to prior evidence of a potentially detrimental effect of rotating night shift work on health and longevity. Copyright © 2015 American Journal of Preventive Medicine. All rights reserved.

Total and Cause-Specific Mortality of U.S. Nurses Working Rotating Night Shifts

PubMed Central

Gu, Fangyi; Han, Jiali; Laden, Francine; Pan, An; Caporaso, Neil E.; Stampfer, Meir J.; Kawachi, Ichiro; Rexrode, Kathryn M.; Willett, Walter C.; Hankinson, Susan E.; Speizer, Frank; Schernhammer, Eva S.

2014-01-01

Background Rotating night shift work imposes circadian strain and is linked to the risk of several chronic diseases. Purpose To examine associations between rotating night shift work and all-cause, cardiovascular disease (CVD), and cancer mortality in a prospective cohort study of 74,862 registered U.S. nurses from the Nurses’ Health Study. Methods Lifetime rotating night shift work (defined as ≥3 nights/month) information was collected in 1988. During 22 years (1988–2010) of follow-up, 14,181 deaths were documented, including 3,062 CVD and 5,413 cancer deaths. Cox proportional hazards models (2013) estimated multivariable-adjusted hazard ratios (HRs) and 95% CIs. Results All-cause and CVD mortality were significantly increased among women with ≥5 years of rotating night shift work, compared to women who never worked night shifts. Specifically, for women with 6–14 and ≥15 years of rotating night shift work, the HRs were 1.11 (95% CI=1.06, 1.17) and 1.11 (95% CI=1.05, 1.18) for all-cause mortality and 1.19 (95% CI=1.07, 1.33) and 1.23 (95% CI=1.09, 1.38) for CVD mortality. There was no association between rotating night shift work and all-cancer mortality (HR≥15years=1.08, 95% CI=0.89, 1.19) or any other cancer, with the exception of lung cancer (HR≥15years=1.25, 95% CI=1.04, 1.51). Conclusions Women working rotating night shifts for ≥5 five years have a modest increase in all-cause and CVD mortality; those working ≥15 years of rotating night shift work have a modest increase in lung cancer mortality. These results add to prior evidence of a potentially detrimental effect of rotating night shift work on health and longevity. PMID:25576495

Systematic Review and Meta-analysis of the Effects of Caffeine in Fatigued Shift Workers: Implications for Emergency Medical Services Personnel

DOT National Transportation Integrated Search

2018-01-11

Background: Emergency Medical Services (EMS) workers may experience fatigue as a consequence of shift work. We reviewed the literature to determine the impact of caffeine as a countermeasure to fatigue in EMS personnel and related shift workers. Meth...

Shift Work and the Relationship with Metabolic Syndrome in Chinese Aged Workers

PubMed Central

Guo, Yanjun; Rong, Yi; Huang, Xiji; Lai, Hanpeng; Luo, Xin; Zhang, Zhihong; Liu, Yuewei; He, Meian; Wu, Tangchun; Chen, Weihong

2015-01-01

Background Shift work is indicated to be associated with adverse metabolic disorders. However, potential effects of shift work on metabolic syndrome (MetS) and its components have not been well established. Methods In total, 26,382 workers from Dongfeng-Tongji Cohort were included in this study. Information on shift work history was gathered through questionnaires and metabolic traits were measured. Logistic regression models were used to calculate the odds ratio (OR) and 95% confidence interval (CI) for long-term shift work related with MetS and each component, respectively. Further stratification analysis was performed to detect the differences on MetS between female and male shift workers. Results Long-term shift work was associated with MetS without adjusting for any confounders. Compared with the group of non-shift work, the multivariate-adjusted ORs (95%CI) of MetS associated with 1–10, 11−20, and ≥20y of shift work were 1.05 (0.95−1.16), 1.14 (1.03−1.26), 1.16 (1.01−1.31), respectively. In female workers, we found a dose-response relationship that every 10 years increase in shift work was associated with a 10% (95% CI: 1%−20%) elevated OR of MetS, while no significant dose-response trend was found among male workers. Furthermore, shift work duration was significantly associated with ORs of high blood pressure (1.07, 1.01−1.13), long waist circumference (1.10, 1.01−1.20) and high glucose levels (1.09, 1.04−1.15). No significant association was observed between shift work and low HDL cholesterol) and raised triglyceride levels. Conclusions Long-term shift work was associated with metabolic syndrome and the association might differ by gender in retired workers. Applicable intervention strategies are needed for prevention of metabolic disorders for shift workers. PMID:25761114

Shift work is associated with reduced heart rate variability among men but not women.

PubMed

Hulsegge, Gerben; Gupta, Nidhi; Proper, Karin I; van Lobenstein, Natasja; IJzelenberg, Wilhelmina; Hallman, David M; Holtermann, Andreas; van der Beek, Allard J

2018-05-01

Imbalance in the autonomic nervous system due to a disrupted circadian rhythm may be a cause of shift work-related cardiovascular diseases. We aimed to determine the association between shift work and cardiac autonomic activity in blue-collar workers. The study included 665 blue-collar workers aged 18-68 years in different occupations from two Danish cohort studies. Time and frequency domain parameters of heart rate variability (HRV) were measured during sleep using the Actiheart monitor, and used as markers of cardiac autonomic function. Multiple linear regression analyses were used to investigate differences in HRV between day and shift workers. Shift workers had no significantly different HRV parameters than day workers, except for a lower VLF (B: 0.21; 95% CI: -0.36-0.05). The lower VLF was only present among non-night shift workers (p < 0.05) and not among night shift workers (p > 0.05). Results differed significantly by gender (p for interaction < 0.10): among men, shift work was negatively associated with RMSSD (B: -7.83; 95% CI: -14.28-1.38), SDNN (B: -7.0; 95% CI: -12.27-1.78), VLF (B: -0.27; 95% CI: -0.46-0.09) and Total Power (B: -0.61; 95% CI: -1.20-0.03), while among women, shift work was only associated with the LF/HF ratio (B: -0.29; 95% CI: -0.54-0.03). Shift work was particularly associated with lower HRV during sleep among men. This indicates that shift work causes imbalance in the autonomic nervous system among men, which might increase their risk of cardiovascular diseases. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Shift Work Disorder Among Oil Rig Workers in the North Sea

PubMed Central

Waage, Siri; Moen, Bente Elisabeth; Pallesen, Ståle; Eriksen, Hege R.; Ursin, Holger; Åkerstedt, Torbj⊘rn; Bjorvatn, Bj⊘rn

2009-01-01

Study Objectives: Shift work disorder (SWD) is a circadian rhythm sleep disorder caused by work hours during the usual sleep period. The main symptoms are excessive sleepiness and insomnia temporally associated with the working schedule. The aim of the present study was to examine SWD among shift workers in the North Sea. Design and Participants: A total of 103 shift workers (2 weeks on 7 nights/ 7days, 12-h shifts, 4 weeks off), mean age 39.8 years, working at an oil rig in the North Sea responded to a questionnaire about SWD. They also completed the Pittsburgh Sleep Quality Index, Bergen Insomnia Scale, Epworth Sleepiness Scale, Composite Morningness Questionnaire, Subjective Health Complaint Inventory, Demand/Control, and Instrumental Mastery Oriented Coping (based on the Utrecht Coping list). Most of these instruments were administered during the first day of the 2-week working period, thus reflecting symptoms and complaints during the 4-week non-work period. The shift workers were also compared to day workers at the oil rig. Results: Twenty-four individuals were classified as suffering from SWD, yielding a prevalence for SWD of 23.3%. During the 4-week non-work period, individuals with SWD reported significantly poorer sleep quality, as measured by the Pittsburgh Sleep Quality Index, and more subjective health complaints than individuals not having SWD. There were no differences between the 2 groups in sleepiness, insomnia, circadian preference, psychological demands, or control. Individuals with SWD reported significantly lower scores on coping. The reports of shift workers without SWD were similar to those of day workers regarding sleep, sleepiness, subjective health complaints, and coping. Conclusions: The prevalence of SWD was relatively high among these shift workers. Individuals with SWD reported poorer sleep quality and more subjective health complaints in the non-work period than shift workers not having SWD. Citation: Waage S; Moen BE; Pallesen S; Eriksen HR; Ursin H; Åkerstedt T; BjorvatnB. Shift work disorder among oil rig workers in the North Sea. SLEEP 2009;32(4):558-565. PMID:19413151

Short sleep duration among workers--United States, 2010.

PubMed

2012-04-27

Insufficient sleep can have serious and sometimes fatal consequences for fatigued workers and others around them. For example, an estimated 20% of vehicle crashes are linked to drowsy driving. The National Sleep Foundation recommends that healthy adults sleep 7-9 hours per day. To assess the prevalence of short sleep duration among workers, CDC analyzed data from the 2010 National Health Interview Survey (NHIS). The analysis compared sleep duration by age group, race/ethnicity, sex, marital status, education, and employment characteristics. Overall, 30.0% of civilian employed U.S. adults (approximately 40.6 million workers) reported an average sleep duration of ≤6 hours per day. The prevalence of short sleep duration (≤6 hours per day) varied by industry of employment (range: 24.1%-41.6%), with a significantly higher rate of short sleep duration among workers in manufacturing (34.1%) compared with all workers combined. Among all workers, those who usually worked the night shift had a much higher prevalence of short sleep duration (44.0%, representing approximately 2.2 million night shift workers) than those who worked the day shift (28.8%, representing approximately 28.3 million day shift workers). An especially high prevalence of short sleep duration was reported by night shift workers in the transportation and warehousing (69.7%) and health-care and social assistance (52.3%) industries. Targeted interventions, such as evidence-based shift system designs that improve sleep opportunities and evidence-based training programs on sleep and working hours tailored for managers and employees, should be implemented to protect the health and safety of workers, their coworkers, and the public.

Shift work, age, and performance : investigation of the 2-2-1 shift schedule used in air traffic control facilities. I., The sleep/wake cycle.

DOT National Transportation Integrated Search

1995-05-01

Air Traffic Control Specialists (ATCS) work rotating shift schedules for most of their careers. Specifically, many work a counterclockwise rotating shift schedule, called the 2-2-1, or some variation of the schedule. The 2-2-1 involves rotating from ...

Air Force Shift Worker Fatigue Survey

DTIC Science & Technology

2005-08-01

ensuring that health care and counseling services are available to employees who work non-traditional schedules. "* " Employees may consider various ways for...responded: Shift workers 1stSgt/CC Environmental (noise, lighting, temp., etc.): 35% 35% Family: 15% 14% Health factors (diet, stress, insomnia): 8% 14...fatigue and equity problems reported by the shift workers . 14. An automated shift work scheduling tool is needed’°. Sleep Hygiene and Health Issues

Associations of Short Sleep and Shift Work Status with Hypertension among Black and White Americans

PubMed Central

Ceïde, Mirnova E.; Pandey, Abhishek; Ravenell, Joe; Donat, Margaret; Ogedegbe, Gbenga; Jean-Louis, Girardin

2015-01-01

Objective. The purpose of this study was to investigate whether short sleepers (<6 hrs) who worked the non-day-shift were at greater likelihood of reporting hypertension and if these associations varied by individuals' ethnicity. Methods. Analysis was based on the 2010 National Health Interview Survey (NHIS). A total of 59,199 American adults provided valid data for the present analyses (mean age = 46.2 ± 17.7 years; 51.5% were female). Respondents provided work schedule and estimated habitual sleep durations as well as self-report of chronic conditions. Results. Of the sample, 30.8% reported a diagnosis of hypertension, 79.1% reported daytime shift work, 11.0% reported rotating shift work, and 4.0% reported night shift work. Logistic regression analysis showed that shift work was significantly associated with hypertension among Blacks [OR = 1.35, CI: 1.06–1.72. P < 0.05], but not among Whites [OR = 1.01, CI: 0.85–1.20, NS]. Black shift workers sleeping less than 6 hours had significantly increased odds of reporting hypertension [OR = 1.81, CI: 1.29–2.54, P < 0.01], while their White counterparts did not [OR = 1.17, CI: 0.90–1.52, NS]. Conclusions. Findings suggest that Black Americans working the non-day-shift especially with short sleep duration have increased odds of reporting hypertension. PMID:26495140

Recovery after shift work: Relation to coronary risk factors in women.

PubMed

Axelsson, John; Lowden, Arne; Kecklund, Göran

2006-01-01

Shift work increases the risk for developing cardiovascular disease. There is, however, little knowledge of what aspects of shift scheduling that are detrimental and what characteristics promote good health. The aim of the present study was to evaluate whether coronary risk factors deteriorate after a hard work period and whether recovery, in the form of a week off, was sufficient to improve them. A total of 19 women worked an extremely rapidly rotating and clockwise shift schedule at a paper and pulp factory. They underwent two health examinations, one at the end of the work period and one after the week off. In addition, the women were divided into a tolerant and a vulnerable group, depending on their satisfaction with their work hours. Most risk factors did not change, but total cholesterol and low-density lipoprotein (LDL)-cholesterol were lower after the working period than after the week-off. In addition, vulnerable women had higher levels of total cholesterol and a higher ratio of total cholesterol/high-density lipoprotein (HDL) than tolerant ones. In conclusion, the finding that a week-off worsens cholesterol levels was against our hypothesis and suggests further studies on how activities/responsibilities outside the workplace affect shift-working women. It was also shown that susceptible shift workers had worse lipid profiles.

Breast cancer screening among shift workers: a nationwide population-based survey in Korea.

PubMed

Son, Heesook; Kang, Youngmi

2017-04-01

We aimed to examine the association between shift work types and participation in breast cancer screening (BCS) programs by comparing rates of participation for BCS among regular daytime workers and alternative shift workers using data from a nationally representative, population-based survey conducted in Korea. In addition, the results were analyzed according to sociodemographic factors, including occupation, education, income, private health insurance, age, and number of working hours a week. This secondary cross-sectional analysis used data from the 2012 Korean National Health and Nutritional Examination Survey. The target population included women aged ≥ 40 years who responded as to whether they had undergone BCS in the previous year. Accordingly, we analyzed survey data for a total of 1,193 women and used a multivariate logistic regression analysis to evaluate the differences in factors affecting BCS between regular daytime and alternative shift workers. A logistic regression analysis was performed considering private health insurance as a significant sociodemographic factor for BCS among regular daytime shift workers. In contrast, none of the tested variables could significantly predict adherence to BCS among alternative shift workers. The results of this study suggest the need for the development of comprehensive workplace breast cancer prevention programs by considering shift work types. More attention should be given to female workers with low education levels, those who are uninsured, and young workers to improve the participation rate for BCS at the workplace.

Night shift work and modifiable lifestyle factors.

PubMed

Pepłońska, Beata; Burdelak, Weronika; Krysicka, Jolanta; Bukowska, Agnieszka; Marcinkiewicz, Andrzej; Sobala, Wojciech; Klimecka-Muszyńska, Dorota; Rybacki, Marcin

2014-10-01

Night shift work has been linked to some chronic diseases. Modification of lifestyle by night work may partially contribute to the development of these diseases, nevertheless, so far epidemiological evidence is limited. The aim of the study was to explore association between night shift work and lifestyle factors using data from a cross-sectional study among blue-collar workers employed in industrial plants in Łódź, Poland. The anonymous questionnaire was self-administered among 605 employees (236 women and 369 men, aged 35 or more) - 434 individuals currently working night shifts. Distribution of the selected lifestyle related factors such as smoking, alcohol drinking, physical activity, body mass index (BMI), number of main meals and the hour of the last meal was compared between current, former, and never night shift workers. Adjusted ORs or predicted means were calculated, as a measure of the associations between night shift work and lifestyle factors, with age, marital status and education included in the models as covariates. Recreational inactivity (defined here as less than one hour per week of recreational physical activity) was associated with current night shift work when compared to never night shift workers (OR = 2.43, 95% CI: 1.13-5.22) among men. Alcohol abstinence and later time of the last meal was associated with night shift work among women. Statistically significant positive relationship between night shift work duration and BMI was observed among men (p = 0.029). This study confirms previous studies reporting lower exercising among night shift workers and tendency to increase body weight. This finding provides important public health implication for the prevention of chronic diseases among night shift workers. Initiatives promoting physical activity addressed in particular to the night shift workers are recommended.

The Relationship Between Shift Work and Men's Health.

PubMed

Deng, Nanfu; Kohn, Taylor P; Lipshultz, Larry I; Pastuszak, Alexander W

2018-01-19

More than 21 million Americans and nearly 20% of the U.S. workforce are shift workers. Non-standard shift work, defined as work that falls outside of 6 am-6 pm, can lead to poor diet, exercise, and sleep habits that lead to decreased productivity, increased workplace accidents, and a variety of negative health outcomes. To investigate the associations between shift work exposure and chronic medical conditions such as metabolic syndromes, cardiovascular disease, gastrointestinal disturbances, and depression as well as urologic complications including hypogonadism, male infertility, lower urinary tract symptoms, and prostate cancer with a focus on the effects of shift work sleep disorder (SWSD) on the severity of these negative health outcomes. We reviewed the literature examining effects of shift work and SWSD on general and urologic health. We produced a summary of effects of shift work on health with focus on the increased risk of negative health outcomes in non-standard shift workers, particularly those with SWSD, when compared to daytime workers or workers without SWSD. Studies have associated non-standard shift work schedules and poor health outcomes, including increased risks of diabetes mellitus, dyslipidemia, hypertension, heart disease, peptic ulcer disease, and depression, in shift workers. However, few studies have focused on the role that shift work plays in men's urologic health. Current evidence supports associations between non-standard shift work and increased hypogonadal symptoms, poor semen parameters, decreased fertility, lower urinary tract symptoms, and prostate cancer. These associations are strengthened by the presence of SWSD, which affects up to 20% of shift workers. Unfortunately, interventions, such as planned naps, timed light exposure, melatonin, and sedative hypnotics, aimed at alleviating excessive nighttime sleepiness and daytime insomnia in non-standard shift workers experiencing SWSD, are limited and lack strong evidence to support their efficacy. Non-standard shift work has been associated with a variety of negative health outcomes and urologic complications, especially with concurrent SWSD. Recognition of these increased risks among shift workers can potentially aid in more effective screening of chronic health and urologic conditions. Non-pharmacologic treatment of SWSD focuses on behavioral therapy and sleep hygiene while melatonin, hypnotics, and stimulants are used to alleviate insomnia and excessive sleepiness of SWSD. Further research into both pharmacologic and non-pharmacologic therapies for SWSD is needed to establish more definitive guidelines in the treatment of SWSD in order to increase productivity, minimize workplace accidents, and improve quality of life for shift workers. Deng N, Kohn TP, Lipshultz LI, et al. The Relationship Between Shift Work and Men's Health. Sex Med Rev 2018;XX:XXX-XXX. Copyright © 2018. Published by Elsevier Inc.

Rotator Cuff Strength Ratio and Injury in Glovebox Workers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weaver, Amelia M.

Rotator cuff integrity is critical to shoulder health. Due to the high workload imposed upon the shoulder while working in an industrial glovebox, this study investigated the strength ratio of the rotator cuff muscles in glovebox workers and compared this ratio to the healthy norm. Descriptive statistics were collected using a short questionnaire. Handheld dynamometry was used to quantify the ratio of forces produced in the motions of shoulder internal and external rotation. Results showed this population to have shoulder strength ratios that were significantly different from the healthy norm. The deviation from the normal ratio demonstrates the need formore » solutions designed to reduce the workload on the rotator cuff musculature of glovebox workers in order to improve health and safety. Assessment of strength ratios can be used to screen for risk of symptom development.« less

The influence of applied internal and external rotation on the pivot shift phenomenon.

PubMed

Kopf, Sebastian; Musahl, Volker; Perka, Carsten; Kauert, Ralf; Hoburg, Arnd; Becker, Roland

2017-04-01

The pivot shift test is performed in different techniques and the rotation of the tibia seems to have a significant impact on the amount of the pivot shift phenomenon. It has been hypothesised that external rotation will increase the phenomenon due to less tension at the iliotibial band in knee extension. Twenty-four patients with unilateral anterior cruciate ligament insufficiency were included prospectively. The pivot shift test was performed bilaterally in internal and external tibial rotation under general anaesthesia. Knee motion was captured using a femoral and a tibial inertial sensor. The difference between positive and negative peak values in Euclidean norm of acceleration was calculated to evaluate the amount of the pivot shift phenomenon. The pivot shift phenomenon was significantly increased in patients with ACL insufficiency when the test was performed in external [mean 5.2 ms - 2 (95% CI 4.3-6.0)] compared to internal tibial rotation [mean 4.4 ms - 2 (95% CI 3.5-5.4)] (p = 0.002). In healthy, contralateral knees did not show any difference between external [mean 4.0 ms - 2 (95% CI 3.3-4.7)] and internal tibial rotation [mean 4.0 ms - 2 (95% CI 3.4-4.6)] (ns). The pivot shift phenomenon was increased with external rotation in ACL-insufficient knees, and therefore, one should perform the pivot shift test, rather, in external rotation to easily evoke the, sometimes difficult to detect, pivot shift phenomenon. I (diagnostic study).

Rotating night shift work, sleep, and colorectal adenoma in women.

PubMed

Devore, Elizabeth E; Massa, Jennifer; Papantoniou, Kyriaki; Schernhammer, Eva S; Wu, Kana; Zhang, Xuehong; Willett, Walter C; Fuchs, Charles S; Chan, Andrew T; Ogino, Shuji; Giovannucci, Edward; Wei, Esther K

2017-07-01

This study aims to investigate the associations of rotating night shift work history and sleep duration with risk of colorectal adenoma. We evaluated 56,275 cancer-free participants of the Nurses' Health Study II, who had their first colonoscopy or sigmoidoscopy between 1991 and 2011; rotating night shift work and sleep duration were reported by mailed questionnaire. Multivariable-adjusted logistic regression was used to estimate relative risks (RR) of colorectal adenoma, with 95% confidence intervals (CI), across categories of rotating night shift work history (none, 1-4, 5-9, and ≥10 years) and sleep duration (≤5, 6, 7, 8, and ≥9 h/day). We found no association between duration of rotating night shift work and occurrence of colorectal adenoma (p-trend across shift work categories = 0.5). Women with the longest durations of rotating night shift work (≥10 years) had a similar risk of adenoma compared to women without a history of rotating night shift work (multivariable-adjusted RR = 0.96, 95% CI = 0.83-1.11). Similarly, there were no associations of shorter or longer sleep durations with adenoma risk (p-trend = 0.2 across sleep durations of ≤5 through 7 h/day and p-trend = 0.5 across sleep durations of 7 through ≥9 h/day). Results were similar when we examined associations according to adenoma location and subtype. Our results do not support an association between rotating night shift work or sleep duration and risk of colorectal adenoma in women.

A 12 year prospective study of circulatory disease among Danish shift workers.

PubMed

Tüchsen, F; Hannerz, H; Burr, H

2006-07-01

Previous studies of the risk of heart disease after shift work reached different estimates and review authors disagree about the validity of some of the studies. A cross sectional study showed that shift workers had a higher prevalence of nearly every unfavourable work environment factor investigated. Conflicts at work and low decision latitude were more frequent among shift workers, and all-day walking or standing work and part-time jobs were more often found among female shift workers. To estimate the risk of circulatory disease in a prospective follow up of a representative sample of gainfully employed Danes, considering known or suspected confounding factors. A cohort of 5517 people who were gainfully employed in 1990 were followed up for all hospital treatments due to circulatory diseases (390-458, ICD-8; I00-I99, ICD-10) from 1991 to 2002 inclusive. A log linear Poisson regression model was applied to control confounding factors and calculate the relative risk for 927 men and women working nights, evenings, or other non-day shifts compared to 4579 day workers. Non-day workers compared to day workers had a relative risk (RR) for all circulatory diseases of 1.31 (95% CI 1.06-1.63). Without control for BMI and smoking, the RR estimate was 1.33 (95% CI 1.07-1.65). For a subgroup of workers with at least three years' seniority, the RR was 1.40 (95% CI 1.09-1.81). The population based aetiological fraction of shift work was estimated to 5%. This study adds to a growing body of evidence suggesting that shift work carries an excess risk of circulatory diseases.

Prevalence of workers with shifts in hearing by industry: a comparison of OSHA and NIOSH Hearing Shift Criteria.

PubMed

Masterson, Elizabeth A; Sweeney, Marie Haring; Deddens, James A; Themann, Christa L; Wall, David K

2014-04-01

The purpose of this study was to compare the prevalence of workers with National Institute for Occupational Safety and Health significant threshold shifts (NSTS), Occupational Safety and Health Administration standard threshold shifts (OSTS), and with OSTS with age correction (OSTS-A), by industry using North American Industry Classification System codes. From 2001 to 2010, worker audiograms were examined. Prevalence and adjusted prevalence ratios for NSTS were estimated by industry. NSTS, OSTS, and OSTS-A prevalences were compared by industry. Twenty percent of workers had an NSTS, 14% had an OSTS, and 6% had an OSTS-A. For most industries, the OSTS and OSTS-A criteria identified 28% to 36% and 66% to 74% fewer workers than the NSTS criteria, respectively. Use of NSTS criteria allowing for earlier detection of shifts in hearing is recommended for improved prevention of occupational hearing loss.

Prevalence of Workers with Shifts in Hearing by Industry: A Comparison of OSHA and NIOSH Hearing Shift Criteria

PubMed Central

Masterson, Elizabeth A.; Sweeney, Marie Haring; Deddens, James A.; Themann, Christa L.; Wall, David K.

2015-01-01

Objective The purpose of this study was to compare the prevalence of workers with National Institute for Occupational Safety and Health significant threshold shifts (NSTS), Occupational Safety and Health Administration standard threshold shifts (OSTS), and with OSTS with age correction (OSTS-A), by industry using North American Industry Classification System codes. Methods 2001-2010 worker audiograms were examined. Prevalence and adjusted prevalence ratios for NSTS were estimated by industry. NSTS, OSTS and OSTS-A prevalences were compared by industry. Results 20% of workers had an NSTS, 14% had an OSTS and 6% had an OSTS-A. For most industries, the OSTS and OSTS-A criteria identified 28-36% and 66-74% fewer workers than the NSTS criteria, respectively. Conclusions Use of NSTS criteria allowing for earlier detection of shifts in hearing is recommended for improved prevention of occupational hearing loss. PMID:24662953

Is task-shifting a solution to the health workers' shortage in Northern Ghana?

PubMed

Okyere, Eunice; Mwanri, Lillian; Ward, Paul

2017-01-01

To explore the experiences and perceptions of health workers and implementers of task-shifting in rural health facilities in Upper East Region, Ghana. Data was collected through field interviews. A total of sixty eight (68) in-depth interviews were conducted with health workers' in primary health care facilities (health centres); Four in-depth interviews with key persons involved in staff management was conducted to understand how task-shifting is organised including its strengths and challenges. The health workers interview guide was designed with the aim of getting data on official tasks of health workers, additional tasks assigned to them, how they perceive these tasks, and the challenges associated with the practice of task-shifting. Task-shifting is a practice being used across the health facilities in the study area to help reduce the impact of insufficient health workers. Generally, health workers had a comprehensive training that supported the organisation of task-shifting. However, staff members' are sometimes engaged in tasks above their level of training and beyond their actual job descriptions. Adequate training is usually not provided before additional tasks are assigned to staff members. Whilst some health workers perceived the additional tasks they performed as an opportunity to learn new skills, others described these as stressful and overburdening. Task-shifting has the potential to contribute to addressing the insufficient health workforce, and thereby improving health delivery system where the procedures are well defined and staff members work in a coordinated and organised manner. The provision of adequate training and supervision for health workers is important in order to improve their expertise before additional tasks are assigned to them so that the quality of care would not be compromised.

Shift work and the assessment and management of shift work disorder (SWD).

PubMed

Wright, Kenneth P; Bogan, Richard K; Wyatt, James K

2013-02-01

Nearly 20% of the labor force worldwide, work shifts that include work hours outside 07:00 h to 18:00 h. Shift work is common in many occupations that directly affect the health and safety of others (e.g., protective services, transportation, healthcare), whereas quality of life, health, and safety during shift work and the commute home can affect workers in any field. Increasing evidence indicates that shift-work schedules negatively influence worker physiology, health, and safety. Shift work disrupts circadian sleep and alerting cycles, resulting in disturbed daytime sleep and excessive sleepiness during the work shift. Moreover, shift workers are at risk for shift work disorder (SWD). This review focuses on shift work and the assessment and management of sleepiness and sleep disruption associated with shift work schedules and SWD. Management strategies include approaches to promote sleep, wakefulness, and adaptation of the circadian clock to the imposed work schedule. Additional studies are needed to further our understanding of the mechanisms underlying the health risks of shift work, understanding which shift workers are at most risk of SWD, to investigate treatment options that address the health and safety burdens associated with shift work and SWD, and to further develop and assess the comparative effectiveness of countermeasures and treatment options. Copyright © 2012 Elsevier Ltd. All rights reserved.

[Night work and shift work - effects on the health of workers].

PubMed

Stryjewski, Piotr J; Kuczaj, Agnieszka; Domal-Kwiatkowska, Dorota; Mazurek, Urszula; Nowalany-Kozielska, Ewa

Number of shift workers increases in developed as well as in developing countries every year and equals 15- 20% of total amount of working people in Europe, 20% of total count of workers in United States of America, 6-32% in Asian countries and 8.1% workers in Poland. This type of employment is connected with such sectors of economy as medical care, industry, mining, transportation, communication and hospitality. The literature review analyses health effects of shift work and night work in the area of gastroenterology, circulatory system, oncologic diseases, neuropsychiatric and sleep disorders. In summary shift and night work have negative impact on human health. Further investigations analyzing impact of shift and night work are needed.

A Survey of Fatigue in Selected United States Air Force Shift Worker Populations

DTIC Science & Technology

2006-03-01

34 (Canadian Health Services Research Foundation, 2000, p. 1). To that end, the present study expanded upon an initial USAF assessment of shift worker ...among permanent night workers . Journal of Occupational Health , 43(6), 301-306. Gawron, V. J., French, J., & Funk, D. (2001). An overview of fatigue...HSW-PE-BR-TR-2006-0003 UNITED STATES AIR FORCE 311th Human Systems Wing A Survey of Fatigue in Selected United States Air Force Shift Worker

Performance and sleepiness in nurses working 12-h day shifts or night shifts in a community hospital.

PubMed

Wilson, Marian; Permito, Regan; English, Ashley; Albritton, Sandra; Coogle, Carlana; Van Dongen, Hans P A

2017-10-05

Hospitals are around-the-clock operations and nurses are required to care for patients night and day. The nursing shortage and desire for a more balanced work-to-home life has popularized 12-h shifts for nurses. The present study investigated sleep/wake cycles and fatigue levels in 22 nurses working 12-h shifts, comparing day versus night shifts. Nurses (11day shift and 11 night shift) were recruited from a suburban acute-care medical center. Participants wore a wrist activity monitor and kept a diary to track their sleep/wake cycles for 2 weeks. They also completed a fatigue test battery, which included the Psychomotor Vigilance Test (PVT) and the Karolinska Sleepiness Scale (KSS), at the beginning, middle and end of 4 duty shifts. Daily sleep duration was 7.1h on average. No overall difference in mean daily sleep duration was found between nurses working day shifts versus night shifts. Objective performance on the PVT remained relatively good and stable at the start, middle, and end of duty shifts in day shift workers, but gradually degraded across duty time in night shift workers. Compared to day shift workers, night shift workers also exhibited more performance variability among measurement days and between participants at each testing time point. The same pattern was observed for subjective sleepiness on the KSS. However, congruence between objective and subjective measures of fatigue was poor. Our findings suggest a need for organizations to evaluate practices and policies to mitigate the inevitable fatigue that occurs during long night shifts, in order to improve patient and healthcare worker safety. Examination of alternative shift lengths or sanctioned workplace napping may be strategies to consider. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physical occupational exposures and health expectancies in a French occupational cohort.

PubMed

Platts, Loretta G; Head, Jenny; Stenholm, Sari; Singh Chungkham, Holendro; Goldberg, Marcel; Zins, Marie

2017-03-01

To examine the relationships of strenuous and hazardous working conditions and rotating shifts that involve night working with life expectancy in good perceived health and life expectancy without chronic disease. The sample contained male gas and electricity workers from the French GAZEL cohort (n=13 393). Six measures of physical working conditions were examined: Self-reports from 1989 and 1990 of ergonomic strain, physical danger, rotating shifts that involve night working and perceived physical strain; company records of workplace injuries and a job-exposure matrix of chemical exposures. Partial healthy life expectancies (age 50-75) relating to (1) self-rated health and (2) chronic health conditions, obtained from annual questionnaires (1989-2014) and company records, were estimated using multistate life tables. The analyses were adjusted for social class and occupational grade. Participants with physically strenuous jobs and who had experienced industrial injuries had shorter partial life expectancy. More physically demanding and dangerous work was associated with fewer years of life spent in good self-rated health and without chronic conditions, with the exception of shift work including nights, where the gradient was reversed. Strenuous and hazardous work may contribute to lost years of good health in later life, which has implications for individuals' quality of life as well as healthcare use and labour market participation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

The effects of work organization on the health of immigrant manual workers: A longitudinal analysis.

PubMed

Arcury, Thomas A; Chen, Haiying; Mora, Dana C; Walker, Francis O; Cartwright, Michael S; Quandt, Sara A

2016-01-01

This analysis uses a longitudinal design to examine the associations of work organization and health outcomes among Latino manual workers. Participants included 247 Latino workers who completed baseline and 1-year follow-up interviews and clinical examinations. Health outcome measures were epicondylitis, rotator cuff syndrome, back pain, and depressive symptoms. Independent measures were measures of job demand, job control, and job support. Workers commonly experienced rotator cuff syndrome (6.5%), back pain (8.9%), and depressive symptoms (11.2%); fewer experienced epicondylitis (2.4%). Psychological demand was associated with rotator cuff syndrome; awkward position and decision latitude were associated with back pain. Decreased skill variety but increased decision latitude was associated with elevated depressive symptoms. Work context factors are important for health outcomes among vulnerable workers. Further research is needed to expand upon this work, particularly cultural perspectives on job support.

Self-Reported Recovery from 2-Week 12-Hour Shift Work Schedules: A 14-Day Follow-Up

PubMed Central

Merkus, Suzanne L.; Holte, Kari Anne; Huysmans, Maaike A.; van de Ven, Peter M.; van Mechelen, Willem; van der Beek, Allard J.

2015-01-01

Background Recovery from fatigue is important in maintaining night workers' health. This study compared the course of self-reported recovery after 2-week 12-hour schedules consisting of either night shifts or swing shifts (i.e., 7 night shifts followed by 7 day shifts) to such schedules consisting of only day work. Methods Sixty-one male offshore employees—20 night workers, 16 swing shift workers, and 25 day workers—rated six questions on fatigue (sleep quality, feeling rested, physical and mental fatigue, and energy levels; scale 1–11) for 14 days after an offshore tour. After the two night-work schedules, differences on the 1st day (main effects) and differences during the follow-up (interaction effects) were compared to day work with generalized estimating equations analysis. Results After adjustment for confounders, significant main effects were found for sleep quality for night workers (1.41, 95% confidence interval 1.05–1.89) and swing shift workers (1.42, 95% confidence interval 1.03–1.94) when compared to day workers; their interaction terms were not statistically significant. For the remaining fatigue outcomes, no statistically significant main or interaction effects were found. Conclusion After 2-week 12-hour night and swing shifts, only the course for sleep quality differed from that of day work. Sleep quality was poorer for night and swing shift workers on the 1st day off and remained poorer for the 14-day follow-up. This showed that while working at night had no effect on feeling rested, tiredness, and energy levels, it had a relatively long-lasting effect on sleep quality. PMID:26929834

Circadian Misalignment Increases C-Reactive Protein and Blood Pressure in Chronic Shift Workers.

PubMed

Morris, Christopher J; Purvis, Taylor E; Mistretta, Joseph; Hu, Kun; Scheer, Frank A J L

2017-04-01

Shift work is a risk factor for inflammation, hypertension, and cardiovascular disease. This increased risk cannot be fully explained by classical risk factors. Shift workers' behavioral and environmental cycles are typically misaligned relative to their endogenous circadian system. However, there is little information on the impact of acute circadian misalignment on cardiovascular disease risk in shift workers, independent of differences in work stress, food quality, and other factors that are likely to differ between night and day shifts. Thus, our objectives were to determine the independent effect of circadian misalignment on 24-h high-sensitivity C-reactive protein (hs-CRP; a marker of systemic inflammation) and blood pressure levels-cardiovascular disease risk factors-in chronic shift workers. Chronic shift workers undertook two 3-day laboratory protocols that simulated night work, comprising 12-hour inverted behavioral and environmental cycles (circadian misalignment) or simulated day work (circadian alignment), using a randomized, crossover design. Circadian misalignment increased 24-h hs-CRP by 11% ( p < 0.0001). Circadian misalignment increased 24-h systolic blood pressure (SBP) and diastolic blood pressure (DBP) by 1.4 mmHg and 0.8 mmHg, respectively (both p ≤ 0.038). The misalignment-mediated increase in 24-h SBP was primarily explained by an increase in SBP during the wake period (+1.7 mmHg; p = 0.017), whereas the misalignment-mediated increase in 24-h DBP was primarily explained by an increase in DBP during the sleep opportunity (+1.8 mmHg; p = 0.005). Circadian misalignment per se increases hs-CRP and blood pressure in shift workers. This may help explain the increased inflammation, hypertension, and cardiovascular disease risk in shift workers.

Applying mathematical modeling to create job rotation schedules for minimizing occupational noise exposure.

PubMed

Tharmmaphornphilas, Wipawee; Green, Benjamin; Carnahan, Brian J; Norman, Bryan A

2003-01-01

This research developed worker schedules by using administrative controls and a computer programming model to reduce the likelihood of worker hearing loss. By rotating the workers through different jobs during the day it was possible to reduce their exposure to hazardous noise levels. Computer simulations were made based on data collected in a real setting. Worker schedules currently used at the site are compared with proposed worker schedules from the computer simulations. For the worker assignment plans found by the computer model, the authors calculate a significant decrease in time-weighted average (TWA) sound level exposure. The maximum daily dose that any worker is exposed to is reduced by 58.8%, and the maximum TWA value for the workers is reduced by 3.8 dB from the current schedule.

[Influence of work intensity on development of arterial hypertension in metal-mining workers].

PubMed

Ustinova, O Iu; Alekseev, V B; Rumiantseva, A N; Orehova, Ia V

2013-01-01

The article covers data on influence of working shifts duration and shift work intensity on cardiovascular system functioning in operators of mining excavators. Findings are that 8 hours shift with regular shift schedule (40 working hours per week) gives significant load on cardiovascular system of workers engaged into underground activities. 50% of mining excavator operators following this working schedule develop transitory arterial hypertension within 10 years. Longer work shift over 8 hours and more intensive shifting schedule over 40 hours per week causes stable arterial hypertension within 3 months in 60% of workers, in 10% of cases associated with lower functioning of sinus node.

Effect of Shift Work on Sleep, Health, and Quality of Life of Health-care Workers.

PubMed

Nena, Evangelia; Katsaouni, Maria; Steiropoulos, Paschalis; Theodorou, Evangelos; Constantinidis, Theodoros C; Tripsianis, Grigorios

2018-01-01

Shift work is associated with sleep disruption, impaired quality of life, and is a risk factor for several health conditions. Aim of this study was to investigate the impact of shift work on sleep and quality of life of health-care workers (HCW). Tertiary University hospital in Greece. Cross-sectional study. Included were HCW, working either in an irregular shift system or exclusively in morning shifts. All participants answered the WHO-5 Well-Being Index (WHO-5) and a questionnaire on demographics and medical history. Shift workers filled the Shift Work Disorders Screening Questionnaire (SWDSQ). Descriptive statistics, Student's t -test, one-way analysis of variance (ANOVA), Pearson's r correlation coefficient, and multivariate stepwise linear regression analysis were applied. Included were 312 employees (87.9% females), 194 working in irregular shift system and 118 in morning shifts. Most shift-workers (58.2%) were somehow or totally dissatisfied with their sleep quality. Regression analysis revealed the following independent determinants for sleep impairment: parenthood ( P < 0.001), age 36-45 years ( P < 0.001), >3 night shifts/week ( P < 0.001), work >5 years in an irregular shift system ( P < 0.001). Diabetes mellitus was the most common medical condition reported by shift workers ( P = 0.008). Comparison between the two groups revealed a significantly impairment in WHO-5 total score, as well as in 4 of 5 of its items ( P < 0.001). Shift-work impairs quality of life, whereas its duration and frequency, along with age and family status of employees can have adverse effects on sleep.

Anxiety about starting three-shift work among female workers: findings from the Female Shift Workers' Health Study.

PubMed

Kubo, Tatsuhiko; Maruyama, Takashi; Shirane, Kiyoyumi; Otomo, Hajime; Matsumoto, Tetsuro; Oyama, Ichiro

2008-03-01

In 1999, the Japanese Law on Equal Employment Opportunity and Conditions was amended and the previous prohibition of the assignment of female workers to night work was abolished. Subsequently, the number of female shift workers has been increasing in Japan, necessitating greater attention to the health care of this population. The aim of the current study is to evaluate the relationship between anxiety expressed about starting three-shift work and background characteristics among female workers who were being assigned to three-shift work for the first time. The subjects were 38 middle-aged female workers (age range: 44 to 59 years) who were working at a chemical plant. The women completed a self-administered questionnaire before starting three-shift work. Levels of anxiety about starting three-shift work were assessed by the question 'Do you feel anxious about starting three-shift work?' The available responses were: 'Very agree', 'Considerably agree', 'Rather agree', 'Slightly agree' and 'Not agree at all', and 63% of the subjects gave one of the first two answers, which were defined as indicating anxiety. We also acquired information regarding lifestyle and occupation for each subject, including the following factors: frequency of breakfast consumption, subjective sleep insufficiency, previous experience of similar work before beginning shift work, previous experience of two-shift work, and responsibility for household duties. In the study, we found a marginally statistically significant trend association between frequent breakfast consumption and anxiety about starting three-shift work (P(trend) = 0.09). Anxiety was also high among subjects with sleep disorders, especially those suffering from subjective sleep insufficiency (P = 0.08). Due to the small study population, these results should be interpreted with caution and confirmed by future studies.

Atypical work schedules are associated with poor sleep quality and mental health in Taiwan female nurses.

PubMed

Lin, Pei-Chen; Chen, Chung-Hey; Pan, Shung-Mei; Pan, Chih-Hong; Chen, Chiou-Jong; Chen, Yao-Mei; Hung, Hsin-Chia; Wu, Ming-Tsang

2012-11-01

To investigate the effects of shift work schedules on sleep quality and mental health in female nurses in south Taiwan. This study recruited 1,360 female registered nurses in the Kaohsiung area for the first survey, and among them, 769 nurses had a rotation shift schedule. Among the 769 rotation shift work nurses, 407 completed another second survey 6-10 months later. Data collection included demographic variables, work status, shift work schedule, sleep quality (Pittsburgh Sleep Quality Index), and mental health (Chinese Health Questionnaire-12). Nurses on rotation shift had the poor sleep quality and mental health compared to nurses on day shift. The nurses on rotation shift had a relatively higher OR of reporting poor sleep quality and poor mental health (OR, 2.26; 95% CI, 1.57-3.28; and OR, 1.91; 95% CI, 1.39-2.63, respectively). Additionally, rotation shift nurses who had ≥2 days off after their most recent night shifts showed significantly improved sleep quality and mental health (PSQI decreased of 1.23 and CHQ-12 decreased of 0.86, respectively). Comparison of sleep quality between the first and second surveys showed aggravated sleep quality only in nurses who had an increased frequency of night shifts. Female nurses who have a rotation shift work schedule tend to experience poor sleep quality and mental health, but their sleep quality and mental health improve if they have ≥2 days off after their most recent night shifts. This empirical information is useful for optimizing work schedules for nurses.

Reversal of orbital angular momentum arising from an extreme Doppler shift

PubMed Central

Toninelli, Ermes; Horsley, Simon A. R.; Hendry, Euan; Phillips, David B.; Padgett, Miles J.

2018-01-01

The linear Doppler shift is familiar as the rise and fall in pitch of a siren as it passes by. Less well known is the rotational Doppler shift, proportional to the rotation rate between source and receiver, multiplied by the angular momentum carried by the beam. In extreme cases the Doppler shift can be larger than the rest-frame frequency and for a red shift, the observed frequency then becomes “negative.” In the linear case, this effect is associated with the time reversal of the received signal, but it can be observed only with supersonic relative motion between the source and receiver. However, the rotational case is different; if the radius of rotation is smaller than the wavelength, then the velocities required to observe negative frequencies are subsonic. Using an acoustic source at ≈100 Hz we create a rotational Doppler shift larger than the laboratory-frame frequency. We observe that once the red-shifted wave passes into the “negative frequency” regime, the angular momentum associated with the sound is reversed in sign compared with that of the laboratory frame. These low-velocity laboratory realizations of extreme Doppler shifts have relevance to superoscillatory fields and offer unique opportunities to probe interactions with rotating bodies and aspects of pseudorelativistic frame translation. PMID:29581257

Biomonitoring of N-ethyl-2-pyrrolidone in automobile varnishers.

PubMed

Koslitz, Stephan; Meier, Swetlana; Schindler, Birgit Karin; Weiss, Tobias; Koch, Holger Martin; Brüning, Thomas; Käfferlein, Heiko Udo

2014-12-01

N-alkyl-2-pyrrolidones are important organic solvents for varnishes in industry. This study investigates exposure to N-ethyl-2-pyrrolidone (NEP) in varnishing of hard plastic components in an automobile plant. Two specific biomarkers of exposure, 5-hydroxy-N-ethyl-2-pyrrolidone (5-HNEP) and 2-hydroxy-N-ethylsuccinimide (2-HESI), were analyzed in urine samples of 14 workers. For this purpose, pre-shift, post-shift and next day pre-shift urine samples were collected midweek. Twelve workers performed regular work tasks (loading, wiping and packing), whereas two workers performed special work tasks including cleaning the sprayer system with organic solvents containing N-alkyl-2-pyrrolidones. Spot urine samples of nine non-exposed persons of the same plant served as controls. Median post-shift urinary levels of workers with regular work tasks (5-HNEP: 0.15 mg/L; 2-HESI: 0.19 mg/L) were ∼5-fold higher compared to the controls (0.03 mg/L each). Continuously increasing metabolite levels, from pre-shift via post-shift to pre-shift samples of the following day, were observed in particular for the two workers with the special working tasks. Maximum levels were 31.01 mg/L (5-HNEP) and 8.45 mg/L (2-HESI). No clear trend was evident for workers with regular working tasks. In summary, we were able to show that workers can be exposed to NEP during varnishing tasks in the automobile industry. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Overweight, obesity and work functioning: the role of working-time arrangements.

PubMed

Nigatu, Yeshambel T; van de Ven, Hardy A; van der Klink, Jac J L; Brouwer, Sandra; Reijneveld, Sijmen A; Bültmann, Ute

2016-01-01

Obesity is associated with productivity loss, but little is known about how obese workers function at work and also the role of working-time arrangements on this association is lacking. Therefore, the aim of this study was to examine the association of overweight and obesity with work functioning (WF), and to determine whether the associations differ between workers with different working-time arrangements. A cross-sectional study was conducted within the sampling frame of the 'Shift Your Work' study that examined the effect of irregular working-times in relation to health and functioning at work. We included N = 622 Dutch employees, of which N = 384 (62%) were shift-workers, N = 171 (27%) on-call workers and N = 67 (11%) day-workers. Overweight and obesity were defined as BMI 25-30 and ≥30, respectively. WF was assessed using the Work-Role Functioning Questionnaire. The prevalences of overweight and obesity were 48% and 10% in all workers, 49% and 11% in shift-workers, 45% and 10% in on-call workers, and 49% and 6% in day workers, respectively. In all workers, obesity was associated with lower WF scores for physical demands (adjusted estimate, aB = -5.5). In shift-workers, obesity was associated with lower WF scores for output and physical demands (aB = -8.8 and -6.8, respectively). In day and on-call workers, overweight and obesity were not associated with WF. Overweight and obesity are highly prevalent in the working population. Obesity might reduce the executive function performance beyond physical limitations, and limit the ability to accomplish tasks successfully, especially in shift workers. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Impact of night-shift work on the prevalence of erosive esophagitis in shipyard male workers.

PubMed

Chung, Tae Heum; Lee, Jiho; Kim, Moon Chan

2016-08-01

Whether night-shift work is a risk factor for gastroesophageal reflux disease is controversial. The aim of this study was to investigate the association between night-shift work and other factors, and erosive esophagitis. A cross-sectional study with 6040 male shipyard workers was performed. Esophagogastroduodenoscopic examination and a survey about night-shift work status, lifestyle, medical history, educational status, and marital status were conducted in all workers. The odds ratios of erosive esophagitis according to night-shift work status were calculated by using the logistic regression model. The prevalence of erosive esophagitis increased in the night-shift workers [odds ratio, 95 % confidence interval: 1.41 (1.03-1.94)]. According to multiple logistic regression models, night-shift work, obesity, smoking, and alcohol consumption of ≥140 g/week were significant risk factors for erosive esophagitis. By contrast, Helicobacter pylori infection was negatively associated with erosive esophagitis. Night-shift work is suggested to be a risk factor for erosive esophagitis. Avoidance of night-shift work and lifestyle modification should be considered for prevention and management of gastroesophageal reflux disease.

Stress in air traffic controllers : comparison of two air route traffic control centers on different shift rotation patterns.

DOT National Transportation Integrated Search

1975-01-01

Stress in 23 air traffic controllers (ATCS) at Atlanta Air Route Traffic Control Center (ATL) on the straight 5-day shift rotation schedule was compared with stress in 23 ATCS's on the 2-2-1 shift rotation schedule at Fort Worth Air Route Traffic Con...

Shorter Versus Longer Shift Durations to Mitigate Fatigue and Fatigue-Related Risks in Emergency Medical Services Personnel and Related Shift Workers: A Systematic Review

DOT National Transportation Integrated Search

2018-01-11

Background: This study comprehensively reviewed the literature on the impact of shorter versus longer shifts on critical and important outcomes for Emergency Medical Services (EMS) personnel and related shift worker groups. Methods: Six databases (e....

The National Shipbuilding Research Program. Ergonomic Study of Shipbuilding and Repair

DTIC Science & Technology

2000-10-09

syndrome, tendinitis , epicondylitis, bicipital tendinitis , rotator cuff tendinitis , disorders due to repetitive trauma, repetitive motion syndrome...Health & Safety is peer of all other managing directors. Ex. Mandatory safety rotation of two months in safety patrol group for all workers. Ex...Mandatory safety rotation of two months in safety patrol group for all workers. Ex. Each team reviews each work-related injury for cause and prevention

Individual and work-related predictors of work outcomes related to sustainable employment among male shift and day workers.

PubMed

van de Ven, Hardy A; Klein Hesselink, John; Bültmann, Ute; de Boer, Michiel R; de Looze, Michiel P; van der Klink, Jac J L; Brouwer, Sandra

2014-05-01

The aim of this study was to examine which individual and work-related characteristics predict work outcomes related to sustainable employment among male shift and day workers. Between 1 September 2005 and 31 December 2009, data on individual and work-related characteristics of N=5640 employees of Tata Steel in the Netherlands were retrieved from the Occupational Health Service and company registers. Work outcomes related to sustainable employment were (i) temporarily being placed in less strenuous work, (ii) sickness absence ≥6 weeks, and (iii) leaving the organization. Cox proportional hazard analyses were performed for all outcome measures. Similar predictors were found for shift and day workers although some differences were observed. For shift workers, high blood pressure and cardiovascular disease were important predictors for sickness absence. For day workers, insomnia was an important predictor of sickness absence ≥6 weeks. Similar predictors in magnitude and direction were found for work outcomes related to sustainable employment among shift and day workers. Interventions aimed at enhancing sustainable employability should focus on individual and work-related characteristics.

Sleep and satisfaction in 8- and 12-h forward-rotating shift systems: Industrial employees prefer 12-h shifts.

PubMed

Karhula, Kati; Härmä, Mikko; Ropponen, Annina; Hakola, Tarja; Sallinen, Mikael; Puttonen, Sampsa

2016-01-01

Twelve-hour shift systems have become more popular in industry. Survey data of shift length, shift rotation speed, self-rated sleep, satisfaction and perceived health were investigated for the associations among 599 predominantly male Finnish industrial employees. The studied forward-rotating shift systems were 12-h fast (12fast, DDNN------, n = 268), 8-h fast (8fast, MMEENN----, n = 161) and 8-h slow (8slow, MMMM-EEEE-NNNN, n = 170). Satisfaction with shift system differed between the groups (p < 0.01) after controlling for age, gender, shift work experience and self-rated stress. In the 12fast, 98% of employees were satisfied with their shift system (75% 8fast, 54% 8slow). Negative effects on sleep and alertness were rare (8%) in the 12fast group (53% 8fast, 66% 8 slow, p < 0.01) and self-reported sleep difficulties were less frequent than in the 8fast and 8slow groups (8%, 27%, 41%, respectively, p < 0.01). The self-reported average sleep duration (12fast 7:50, 8fast 7:24, 8slow 7:15, p < 0.01), and shift-specific sleep before and between morning shifts and after first night shift were longer in the 12fast group. Perceived negative effects of the current shift system on general health (12fast 4%, 8fast 30%, 8slow 41%, p < 0.001) and work-life balance (12fast 8%, 8fast 52%, 8slow 63%, p < 0.001) differed strongly between the groups. In conclusion, the perceived effects of shift work were dependent on both shift length and shift rotation speed: employees in the 12-h rapidly forward-rotating shift system were most satisfied, perceived better work-life balance and slept better than the employees in the 8fast or especially the employees in the 8-h slowly rotating systems.

A laboratory comparison of clockwise and counter-clockwise rapidly rotating shift schedules, part I, sleep : final report.

DOT National Transportation Integrated Search

2002-05-01

INTRODUCTION. Many air traffic control specialists work relatively unique counter-clockwise, rapidly rotating shift schedules. Researchers recommend, however, that if rotating schedules are to be used, they should rotate in a clockwise, rather than a...

Circadian gene expression in peripheral blood leukocytes of rotating night shift nurses.

PubMed

Reszka, Edyta; Peplonska, Beata; Wieczorek, Edyta; Sobala, Wojciech; Bukowska, Agnieszka; Gromadzinska, Jolanta; Lie, Jenny-Anne; Kjuus, Helge; Wasowicz, Wojciech

2013-03-01

It has been hypothesized that the underlying mechanism of elevated breast cancer risk among long-term, night-working women involves circadian genes expression alteration caused by exposure to light at night and/or irregular work hours. The aim of the present study was to determine the effect of rotating night shift work on expression of selected core circadian genes. The cross-sectional study was conducted on 184 matched nurses and midwives, who currently work either day or rotating night shifts, to determine the effect of irregular work at night on circadian gene expression in peripheral blood leukocytes. Transcript levels of BMAL1, CLOCK, CRY1, CRY2, PER1, PER2, and PER3 were determined by means of quantitative real-time polymerase chain reaction (PCR). After adjusting for hour of blood collection, there were no statistically significant changes of investigated circadian genes among nurses and midwives currently working rotating night shifts compared to nurses working day shifts. The highest expression of PER1 messenger ribonucleic acid (mRNA) was observed for women currently working shifts who had worked >15 years in rotating night shift work. PER1 gene expression was associated with the lifetime duration of rotating night shift work among women currently working night shifts (P=0.04). PER1 and PER3 transcript levels in blood leukocytes were significantly down-regulated in the later versus early hours of the morning between 06.00-10.00 hours (β-coefficient -0.226, P=0.001 and β-coefficient -0.181, P<0.0001, respectively). These results suggest that current rotating night shift work does not affect circadian gene expression in human circulating leukocytes. In analysis of the peripheral clock in human studies, the hour of blood collection should be precisely specified.

The effect of expedited rotator cuff surgery in injured workers: a case-control study.

PubMed

Razmjou, Helen; Lincoln, Sandra; Boljanovic, Dragana; Gallay, Stephen; Henry, Patrick; Richards, Robin R; Holtby, Richard

2017-07-01

Expediting rotator cuff surgery is expected to facilitate recovery and return to work in injured workers. This case-control study examined the effect of expedited rotator cuff surgery on recovery and work status in injured workers. Injured workers who had undergone an expedited rotator cuff surgery funded by parallel-pay insurance (study group) were compared with workers who had used the public health insurance (control group) while adjusting for sex, age, severity of pathology, and follow-up period. Disability was measured by the American Shoulder and Elbow Surgeons (ASES) Standardized Assessment Form score. The percentage of patients who exceeded the minimal clinically important difference of 17 points in the ASES was calculated. The study group waited less time to have surgery than the control group (P < .0001), reported less disability after surgery, and had a higher number of patients whose improvement exceeded the minimal clinically important difference (119 vs. 65, P < .0001). The study group was more likely to be working at the time of the final follow-up (P < .0001). The final multivariable regressions, which adjusted for unmatched variables, such as dominant side involvement, mechanism of injury, and associated operations that were different between groups, were consistent with univariable analyses indicating superior results in the study group. Injured workers who underwent expedited rotator cuff surgery reported less disability and had a more successful return to work after surgery than injured workers who waited longer for specialist assessment and surgery within the public health system. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Effects of extended work shifts and shift work on patient safety, productivity, and employee health.

PubMed

Keller, Simone M

2009-12-01

It is estimated 1.3 million health care errors occur each year and of those errors 48,000 to 98,000 result in the deaths of patients (Barger et al., 2006). Errors occur for a variety of reasons, including the effects of extended work hours and shift work. The need for around-the-clock staff coverage has resulted in creative ways to maintain quality patient care, keep health care errors or adverse events to a minimum, and still meet the needs of the organization. One way organizations have attempted to alleviate staff shortages is to create extended work shifts. Instead of the standard 8-hour shift, workers are now working 10, 12, 16, or more hours to provide continuous patient care. Although literature does support these staffing patterns, it cannot be denied that shifts beyond the traditional 8 hours increase staff fatigue, health care errors, and adverse events and outcomes and decrease alertness and productivity. This article includes a review of current literature on shift work, the definition of shift work, error rates and adverse outcomes related to shift work, health effects on shift workers, shift work effects on older workers, recommended optimal shift length, positive and negative effects of shift work on the shift worker, hazards associated with driving after extended shifts, and implications for occupational health nurses. Copyright 2009, SLACK Incorporated.

Common Genetic Variation Near Melatonin Receptor 1A Gene Linked to Job-Related Exhaustion in Shift Workers

PubMed Central

Sulkava, Sonja; Ollila, Hanna M.; Alasaari, Jukka; Puttonen, Sampsa; Härmä, Mikko; Viitasalo, Katriina; Lahtinen, Alexandra; Lindström, Jaana; Toivola, Auli; Sulkava, Raimo; Kivimäki, Mika; Vahtera, Jussi; Partonen, Timo; Silander, Kaisa; Porkka-Heiskanen, Tarja

2017-01-01

Abstract Study Objectives: Tolerance to shift work varies; only some shift workers suffer from disturbed sleep, fatigue, and job-related exhaustion. Our aim was to explore molecular genetic risk factors for intolerance to shift work. Methods: We assessed intolerance to shift work with job-related exhaustion symptoms in shift workers using the emotional exhaustion subscale of the Maslach Burnout Inventory-General Survey, and carried out a genome-wide association study (GWAS) using Illumina’s Human610-Quad BeadChip (n = 176). The most significant findings were further studied in three groups of Finnish shift workers (n = 577). We assessed methylation in blood cells with the Illumina HumanMethylation450K BeadChip, and examined gene expression levels in the publicly available eGWAS Mayo data. Results: The second strongest signal identified in the GWAS (p = 2.3 × 10E-6) was replicated in two of the replication studies with p < .05 (p = 2.0 × 10E-4 when combining the replication studies) and indicated an association of job-related exhaustion in shift workers with rs12506228, located downstream of the melatonin receptor 1A gene (MTNR1A). The risk allele was also associated with reduced in silico gene expression levels of MTNR1A in brain tissue and suggestively associated with changes in DNA methylation in the 5' regulatory region of MTNR1A. Conclusions: These findings suggest that a variant near MTNR1A may be associated with job-related exhaustion in shift workers. The risk variant may exert its effect via epigenetic mechanisms, potentially leading to reduced melatonin signaling in the brain. These results could indicate a link between melatonin signaling, a key circadian regulatory mechanism, and tolerance to shift work. PMID:28364478

Impacts of shift work on sleep and circadian rhythms.

PubMed

Boivin, D B; Boudreau, P

2014-10-01

Shift work comprises work schedules that extend beyond the typical "nine-to-five" workday, wherein schedules often comprise early work start, compressed work weeks with 12-hour shifts, and night work. According to recent American and European surveys, between 15 and 30% of adult workers are engaged in some type of shift work, with 19% of the European population reportedly working at least 2 hours between 22:00 and 05:00. The 2005 International Classification of Sleep Disorders estimates that a shift work sleep disorder can be found in 2-5% of workers. This disorder is characterized by excessive sleepiness and/or sleep disruption for at least one month in relation with the atypical work schedule. Individual tolerance to shift work remains a complex problem that is affected by the number of consecutive work hours and shifts, the rest periods, and the predictability of work schedules. Sleepiness usually occurs during night shifts and is maximal at the end of the night. Impaired vigilance and performance occur around times of increased sleepiness and can seriously compromise workers' health and safety. Indeed, workers suffering from a shift work sleep-wake disorder can fall asleep involuntarily at work or while driving back home after a night shift. Working on atypical shifts has important socioeconomic impacts as it leads to an increased risk of accidents, workers' impairment and danger to public safety, especially at night. The aim of the present review is to review the circadian and sleep-wake disturbances associated with shift work as well as their medical impacts. Copyright © 2014. Published by Elsevier SAS.

Extent, Nature, and Risk Factors of Workplace Violence in Public Tertiary Hospitals in China: A Cross-Sectional Survey

PubMed Central

Liu, He; Zhao, Siqi; Jiao, Mingli; Wang, Jingtao; Peters, David H.; Qiao, Hong; Zhao, Yuchong; Li, Ye; Song, Lei; Xing, Kai; Lu, Yan; Wu, Qunhong

2015-01-01

Using a cross-sectional survey design from 11 public tertiary hospitals (a specialist hospital, four Chinese medicine hospitals, and six general hospitals) in the urban areas of Heilongjiang, we determined the nature of workplace violence that medical staff have encountered in Chinese hospitals and identified factors associated with those experiences of violence. A total of 1129 health workers participated. The specialist hospital had the highest prevalence of physical violence (35.4%), while the general hospitals had the highest prevalence of non-physical violence (76%). Inexperienced medical staff (p < 0.001) were more likely to suffer non-physical violence than physical violence in Chinese medicine hospitals compared to experienced staff. Medical units (p = 0.001) had a high risk of non-physical violence, while surgical units (p = 0.005) had a high risk of physical violence. In general hospitals, staff with higher levels of anxiety about workplace violence were more vulnerable to both physical violence (1.67, 95% CI 1.36–2.10) and non-physical violence (1.309, 95% CI 1.136–1.508) compared to those with lower levels of anxiety, while rotating shift workers had a higher odds of physical violence (2.2, 95% CI 1.21–4.17) and non-physical violence (1.65, 95% CI 1.13–2.41) compared to fixed day shift workers. Thus, prevention should focus not only on high-risk sections of hospitals, but also on the nature of the hospital itself. PMID:26086703

Reversal of orbital angular momentum arising from an extreme Doppler shift.

PubMed

Gibson, Graham M; Toninelli, Ermes; Horsley, Simon A R; Spalding, Gabriel C; Hendry, Euan; Phillips, David B; Padgett, Miles J

2018-04-10

The linear Doppler shift is familiar as the rise and fall in pitch of a siren as it passes by. Less well known is the rotational Doppler shift, proportional to the rotation rate between source and receiver, multiplied by the angular momentum carried by the beam. In extreme cases the Doppler shift can be larger than the rest-frame frequency and for a red shift, the observed frequency then becomes "negative." In the linear case, this effect is associated with the time reversal of the received signal, but it can be observed only with supersonic relative motion between the source and receiver. However, the rotational case is different; if the radius of rotation is smaller than the wavelength, then the velocities required to observe negative frequencies are subsonic. Using an acoustic source at [Formula: see text]100 Hz we create a rotational Doppler shift larger than the laboratory-frame frequency. We observe that once the red-shifted wave passes into the "negative frequency" regime, the angular momentum associated with the sound is reversed in sign compared with that of the laboratory frame. These low-velocity laboratory realizations of extreme Doppler shifts have relevance to superoscillatory fields and offer unique opportunities to probe interactions with rotating bodies and aspects of pseudorelativistic frame translation. Copyright © 2018 the Author(s). Published by PNAS.

Shift work, safety, and aging.

PubMed

Folkard, Simon

2008-04-01

It has long been recognized that older shift workers may have shorter and more disturbed day sleeps between successive night shifts than their younger colleagues. This has given rise to considerable concern over the safety of aging shift workers because of the increasing age of the work force and increases in retirement age. Because there have been no direct studies of the combined effects of shift work and age on safety, the present paper begins by reviewing the literature relating safety to features of shift systems. It then considers the general effect of age on occupational injury rates before examining existing evidence of the combined effects of shift work and age on performance capabilities. The results of the literature review indicate that when the a priori risk is constant, there is reasonably clear evidence that injury rates are higher at night, and that they increase over successive night shifts more rapidly than over successive day shifts. Further, although occupational injuries are less frequent in older workers, those that do occur tend to be more serious. Finally, there is some suggestive evidence from studies of objectively measured performance capabilities that older workers may be less able to both maintain their performance over the course of a night shift and cope with longer spans of successive night shifts. It is concluded that it seems possible, even though unproven as yet, that older workers may be at greater risk both to injury and accident on the night shift. There is a strong need for future epidemiological studies of the combined effects of shift work and age on injuries and accidents, and that these should attempt to separate the effects of age per se from those of generation.

The association between rotating shift work and increased occupational stress in nurses.

PubMed

Lin, Pei-Chen; Chen, Chung-Hey; Pan, Shung-Mei; Chen, Yao-Mei; Pan, Chih-Hong; Hung, Hsin-Chia; Wu, Ming-Tsang

2015-01-01

The aim of this study was to investigate whether rotating shift work increases occupational stress in nurses. This study measured shift work scheduling and occupational stress by using the Effort-Reward Imbalance model with self-reported questionnaires in a sample of 654 female nurses. Overcommitment risk was higher in nurses who worked rotating shifts than in those who worked day/non-night shifts (OR, 2.16; 95% CI, 1.03-4.66). However, an effort/reward imbalance was not directly associated with work schedules (OR, 1.88; 95% CI, 0.87-4.35). Among nurses working rotation rotating shifts, those who had 2 days off after their most recent night shifts showed an alleviated risk of overcommitment (OR, 0.52; 95% CI, 0.32-0.82), but those who had worked for at least one series of 7 consecutive work days per month had an increased risk of effort/reward imbalance (OR, 2.75; 95% CI, 1.69-4.48). Additionally, those who had little or no participation in planning working hours and shift scheduling and worked overtime at least three times per week during the preceding 2 months tended to have high stress. The nurses who worked rotating shifts tended to experience work-related stress, but their stress levels improved if they had at least 2 days off after their most recent night shift and if they were not scheduled to work 7 consecutive days. These empirical data can be used to optimize work schedules for nurses to alleviate work stress.

Effects of shift changes on female workers at a dish factory.

PubMed

Hirose, T; Tada, Y; Hasegawa, M

2001-12-01

This study investigated the effects of working night shifts on social and family life by examining changes in workers' daily life before and after a change in their shifts. Subjects were 40 women aged 27-59 years, working at a dish factory. During the health examination of night workers in autumn of 2000, the subjects were directly interviewed about changes in their lives induced by the shift change. Question parameters consisted of 8 items including 30 sub-items related to social and family life, such as sleep, rest, meals, sports, family time, hobbies, neighborhood association and social activities. The subjects selected one of four response categories: "becoming worse", "no change", "becoming better" and "difficult to determine." With regard to the percentage of "becoming worse", meal-related items ranked high in all of the shift types. "Family time" and "hobbies" showed high percentages in the subjects transferring from day shifts to night shifts, and in those transferring from early-morning shifts to night shifts. "Rest", "sports" and "hobbies" showed high percentages in the subjects transferring from night shifts to midnight shifts. Decreased sleeping hours were confirmed in all of the shift types, while the subjects tended to sleep more soundly. As the workers transfer to shifts at earlier hours, they were obliged to make sacrifices in various aspects of their social and family life. Therefore, much assistance in this regard should be given to them.

A model for developing job rotation schedules that eliminate sequential high workloads and minimize between-worker variability in cumulative daily workloads: Application to automotive assembly lines.

PubMed

Yoon, Sang-Young; Ko, Jeonghan; Jung, Myung-Chul

2016-07-01

The aim of study is to suggest a job rotation schedule by developing a mathematical model in order to reduce cumulative workload from the successive use of the same body region. Workload assessment using rapid entire body assessment (REBA) was performed for the model in three automotive assembly lines of chassis, trim, and finishing to identify which body part exposed to relatively high workloads at workstations. The workloads were incorporated to the model to develop a job rotation schedule. The proposed schedules prevent the exposure to high workloads successively on the same body region and minimized between-worker variance in cumulative daily workload. Whereas some of workers were successively assigned to high workload workstation under no job rotation and serial job rotation. This model would help to reduce the potential for work-related musculoskeletal disorders (WMSDs) without additional cost for engineering work, although it may need more computational time and relative complex job rotation sequences. Copyright © 2016 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Workplace Bullying among Healthcare Workers

PubMed Central

Ariza-Montes, Antonio; Muniz, Noel M.; Montero-Simó, María José; Araque-Padilla, Rafael Angel

2013-01-01

This paper aims to assess consistent predictors through the use of a sample that includes different actors from the healthcare work force to identify certain key elements in a set of job-related organizational contexts. The utilized data were obtained from the 5th European Working Conditions Survey, conducted in 2010 by the European Foundation for the Improvement of Living and Working Conditions. In light of these objectives, we collected a subsample of 284 health professionals, some of them from the International Standard Classification of Occupations—subgroup 22—(ISCO-08). The results indicated that the chance of a healthcare worker referring to him/herself as bullied increases among those who work on a shift schedule, perform monotonous and rotating tasks, suffer from work stress, enjoy little satisfaction from their working conditions, and do not perceive opportunities for promotions in their organizations. The present work summarizes an array of outcomes and proposes within the usual course of events that workplace bullying could be reduced if job demands were limited and job resources were increased. The implications of these findings could assist human resource managers in facilitating, to some extent, good social relationships among healthcare workers. PMID:23887621

Circadian type, chronic fatigue, and serum IgM in the shift workers of an industrial organization

PubMed Central

Khaleghipour, Shahnaz; Masjedi, Mohsen; Kelishadi, Roya

2015-01-01

Background: Night shift workers are more vulnerable to immune-related diseases. Immunoglobulin M (IgM) is a potent activator of complement, and complement has a crucial role in defense against bacterial infections. Circadian type is known as an effective agent on vulnerability and adaptation with shift work due to non-compliance with shift stress. The objective of this study was to investigate the correlation of circadian type and chronic fatigue with the serum concentration of IgM in a group of shift workers. Materials and Methods: This cross-sectional study was performed in an industrial organization in Isfahan, Iran. The study population consisted of 221 male employees working at night shifts who were selected by random cluster sampling. The following questionnaires were used: composite morningness (Torsvall and Akerstedt), circadian type (Folkard), and chronic fatigue (Barton and colleagues). The serum concentration of IgM was measured by the nephelometric method. The data were analyzed with the Pearson coefficient correlation and the path analysis for finding the pattern of the structural equations to evaluate the direct and indirect relationships between variables, using the SPSS 15 and LISREL 8.5 statistical software. Results: Significant correlation was documented between morningness, flexibility, languidness, and chronic fatigue with the serum concentration of IgM (P < 0.01). Conclusion: The results showed that the shift workers with morningness and languidness experienced more problems during the working hours due to more tiredness, and had decreased serum concentration of IgM. Correct management of shift work may attenuate fatigue in workers and also improve many health issues experienced by the shift workers. PMID:25802830

Association between shift work and being overweight or obese among health care workers in a clinical setting in Medellin, Colombia.

PubMed

Gomez-Parra, Myrna; Romero-Arrieta, Lydis; Vasquez-Trespalacios, Elsa Maria; Palacio-Jaramillo, Veronica; Valencia-Martinez, Andrea

2016-11-22

Shift work is common in health care settings and has been hypothesized as a risk factor for being overweight or obese. We examined the relation between shift work and being overweight or obese, adjusting for stress and lifestyle habits in Colombian health care workers. The aim of this study was to assess the association between shift work and being overweight/obese in employees of a health care setting in Medellin, Colombia. This cross-sectional study was carried out among 200 workers in a health care setting. Participants completed a demographic, occupational, work-related stress and life style questionnaire. Their Body Mass Index (BMI) and waist to hip ratio were also measured. The study sample consisted of 160 (80%) females and 40 (20%) males. Mean age was 35.1±9.1 years and mean BMI was 25±3.9. After adjusting for potential confounders, multivariate logistic regression revealed no statistically significant association between being overweight, being obese or waist to hip ratio and shift work; 95% CI OR: 1.08 (0.62-1.89), 1.33 (0.44-3.99) and 1.2 (0.8-1.9), respectively. Day workers were statistically more likely to smoke, work more hours, and have a higher educational level than shift workers. No significant associations between shift work and being overweight/obese were observed in health care workers in a Colombian setting. These findings need to be confirmed through longitudinal studies.

[Shift Work among Men and Women on the Threshold to Higher Working Age - Working Conditions and Health Status].

PubMed

Leser, C; Tisch, A; Tophoven, S

2016-11-01

Background: The number of older employees in shift and night work has increased significantly in recent years. Furthermore, the proportion of women in shift and night work has increased markedly. This is due to the aging workforce and the expansion of shift work in the tertiary sector. Previous research shows that shift work is often associated with health risks. Against this background, the aim of the present study is to examine the situation of working men and women on the threshold to higher working age with regard to the relationship between shift work and physical health. Methods: We employed data from the study "lidA - leben in der Arbeit" German Cohort Study on Work, Age and Health, a survey of the German baby boom cohorts born in 1959 and 1965 (n=5 637). Linear regression models are used to study the effect of shift work - with and without night work - and of further work exposures on the baby boomers' physical health status. The models control for sleep and health-related behaviour and are stratified by gender. Among women, also the scope of work was taken into account. Results: The results show that male shift workers are burdened by their on average lower occupational status and by physical exposure; female shift workers additionally suffer from high personal effort and low rewards and female part-time shift workers also from overcommitment. Conclusion: Working conditions of shift workers are strongly characterised by work stress. In order to preserve aging shift workers' work ability, some organisational measures seem necessary. In this context, occupational safety and health management as well as opportunities for recovery and encouraging leadership should be considered. © Georg Thieme Verlag KG Stuttgart · New York.

Individual vulnerability to insomnia, excessive sleepiness and shift work disorder amongst healthcare shift workers. A systematic review.

PubMed

Booker, Lauren A; Magee, Michelle; Rajaratnam, Shantha M W; Sletten, Tracey L; Howard, Mark E

2018-03-27

Shift workers often experience reduced sleep quality, duration and/or excessive sleepiness due to the imposed conflict between work and their circadian system. About 20-30% of shift workers experience prominent insomnia symptoms and excessive daytime sleepiness consistent with the circadian rhythm sleep disorder known as shift work disorder. Individual factors may influence this vulnerability to shift work disorder or sleep-related impairment associated with shift work. This paper was registered with Prospero and was conducted using recommended standards for systematic reviews and meta-analyses. Published literature that measured sleep-related impairment associated with shift work including reduced sleep quality and duration and increased daytime sleepiness amongst healthcare shift workers and explored characteristics associated with individual variability were reviewed. Fifty-eight studies were included. Older age, morning-type, circadian flexibility, being married or having children, increased caffeine intake, higher scores on neuroticism and lower on hardiness were related to a higher risk of sleep-related impairment in response to shift work, whereas physical activity was a protective factor. The review highlights the diverse range of measurement tools used to evaluate the impact of shift work on sleep. Use of standardised and validated tools would enable cross-study comparisons. Longitudinal studies are required to establish causal relationships between individual factors and the development of shift work disorder. Copyright © 2018 Elsevier Ltd. All rights reserved.

Rotating shift work associated with obesity in men from northeastern Ontario

PubMed Central

Anne, Grundy; Michelle, Cotterchio; Victoria A., Kirsh; Victoria, Nadalin; Nancy, Lightfoot; Loretta, Ryan; Nancy, Kreiger

2017-01-01

Abstract Introduction: While some studies have suggested associations between shift work and obesity, few have been population-based or considered multiple shift schedules. Since obesity is linked with several chronic health conditions, understanding which types of shift work influence obesity is important and additional work with more detailed exposure assessment of shift work is warranted. Methods: Using multivariate polytomous logistic regression, we investigated the associations between shift work (evening/night, rotating and other shift schedules) and overweight and obesity as measured by body mass index cross-sectionally among 1561 men. These men had previously participated as population controls in a prostate cancer case-control study conducted in northeastern Ontario from 1995 to 1999. We obtained information on work history (including shift work), height and weight from the existing self-reported questionnaire data. Results: We observed an association for ever (vs. never) having been employed in rotating shift work for both the overweight (OR [odds ratio] = 1.34; 95% CI [confidence interval]: 1.05–1.73) and obese (OR = 1.57; 95% CI: 1.12–2.21) groups. We also observed nonsignificant associations for ever (vs. never) having been employed in permanent evening/night shifts. In addition, we found a significant trend of increased risk for both overweight and obesity with increasing duration of rotating shift work. Conclusion: Both the positive association between rotating shift work and obesity and the suggested positive association for permanent evening/night shift work in this study are consistent with previous findings. Future population-based research that is able to build on our results while examining additional shift work characteristics will further clarify whether some shift patterns have a greater impact on obesity than others. PMID:28800293

Rotating shift work associated with obesity in men from northeastern Ontario.

PubMed

Grundy, Anne; Cotterchio, Michelle; Kirsh, Victoria A; Nadalin, Victoria; Lightfoot, Nancy; Kreiger, Nancy

2017-08-01

While some studies have suggested associations between shift work and obesity, few have been population-based or considered multiple shift schedules. Since obesity is linked with several chronic health conditions, understanding which types of shift work influence obesity is important and additional work with more detailed exposure assessment of shift work is warranted. Using multivariate polytomous logistic regression, we investigated the associations between shift work (evening/night, rotating and other shift schedules) and overweight and obesity as measured by body mass index cross-sectionally among 1561 men. These men had previously participated as population controls in a prostate cancer case-control study conducted in northeastern Ontario from 1995 to 1999. We obtained information on work history (including shift work), height and weight from the existing self-reported questionnaire data. We observed an association for ever (vs. never) having been employed in rotating shift work for both the overweight (OR [odds ratio] = 1.34; 95% CI [confidence interval]: 1.05-1.73) and obese (OR = 1.57; 95% CI: 1.12-2.21) groups. We also observed nonsignificant associations for ever (vs. never) having been employed in permanent evening/night shifts. In addition, we found a significant trend of increased risk for both overweight and obesity with increasing duration of rotating shift work. Both the positive association between rotating shift work and obesity and the suggested positive association for permanent evening/night shift work in this study are consistent with previous findings. Future population-based research that is able to build on our results while examining additional shift work characteristics will further clarify whether some shift patterns have a greater impact on obesity than others.

Absenteeism of shift and day workers: A study of six types of shift system in 29 organizations

PubMed Central

Taylor, P. J.; Pocock, S. J.; Sergean, R.

1972-01-01

Taylor, P. J., Pocock, S. J., and Sergean, R. (1972).Brit. J. industr. Med.,29, 208-213. Absenteeism of shift and day workers. Previous evidence on the effects of shift work upon absence behaviour is conflicting, this being due in part to the variety of shift systems in use. A study is described in which absence records over two years were obtained for 965 matched pairs of shift and day workers from 29 organizations. Six types of shift system were involved, providing comprehensive coverage of shift work in the United Kingdom. Matching was achieved for sex, age, workplace, and occupation. Absence records included certified sickness, short sickness, and non-medical absence. The overall results showed that shift workers had less absence of all three types than their colleagues on day work, this difference being most marked in the numbers of men having several episodes. No significant differences were found in the diagnostic pattern of certified absence. Comparisons between day work and each of the six types of shift work did not provide any definite conclusions as to their relative merits as far as absence is concerned. The results from the different organizations were not wholly consistent, but a substantial majority followed the general trend. PMID:5022000

Night-shift work is associated with increased pain perception.

PubMed

Matre, Dagfinn; Knardahl, Stein; Nilsen, Kristian Bernhard

2017-05-01

Objectives The aim of the present study was to determine whether shift workers exhibit increased perception of experimentally induced pain after working night shifts. Methods The study was a paired cross-over design with two sleep conditions, after at least two nights of habitual sleep and after two consecutive night shifts at work. Fifty-three nurses in rotating shift work participated. The sensitivity to electrically induced pain, heat pain, cold pain, pressure pain and pain inhibition was determined experimentally in each sleep condition. Sleepiness and vigilance were also assessed. Results Night-shift work (NSW) increased the sensitivity to electrically induced pain and heat pain (P≤0.001). Relative to habitual sleep, electrically induced pain increased by 22.3% and heat pain increased by 26.5%. The sensitivity to cold and pressure pain did not change, changes relative to habitual sleep was <5% (P>0.5). Pain inhibition was 66.9% stronger after NSW versus after habitual sleep (P<0.001). Sleepiness (measured with the Karolinska Sleepiness Scale) increased from 4.1 after habitual sleep to 6.9 after NSW (P<0.001). Vigilance decreased after NSW, measured as a 0.03-second decrease in reaction time (P<0.005). Conclusions Changes in pain sensitivity after NSW is measurable with clinically relevant effect sizes and may be an important marker for studies comparing the physiological effects of different shift work schedules. Explanations for the differential effect on different pain modalities should be a focus for future studies.

Job characteristics and musculoskeletal pain among shift workers of a poultry processing plant in Southern Brazil.

PubMed

Barro, Dânia; Olinto, Maria Teresa Anselmo; Macagnan, Jamile Block Araldi; Henn, Ruth Liane; Pattussi, Marcos Pascoal; Faoro, Mariana Wentz; Garcez, Anderson da Silva; Paniz, Vera Maria Vieira

2015-01-01

The purpose of this study was to evaluate the association between job characteristics and musculoskeletal pain among shift workers employed at a 24-hour poultry processing plant in Southern Brazil. This was a cross-sectional study of 1,103 production line workers aged 18-52 years. The job characteristics of interest were shift (day/night), shift duration, and plant sector ambient temperature. Musculoskeletal pain was defined as self-reported occupational-related pain in the upper or lower extremities and trunk, occurring often or always, during the last 12 months. The mean (SD) participant age was 30.8 (8.5) years, and 65.7% of participants were women. The prevalence of musculoskeletal pain was greater among female participants than male participants. After adjustment for job characteristics and potential confounders, the prevalence ratios (PR) of lower extremity musculoskeletal pain among female workers employed in extreme-temperature conditions those working the night shift, and those who had been working longer on the same shift were 1.75 (95% CI 1.12, 2.71), 1.69 (95% CI 1.05, 2.70), and 1.64 (95% CI 1.03, 2.62), respectively. In male workers, only extreme-temperature conditions showed a significant association with lower extremity musculoskeletal pain (PR=2.17; 95% CI 1.12, 4.22) after adjustment analysis. These findings suggest a need for implementation of measures to mitigate the damage caused by nighttime work and by working under extreme temperature conditions, especially among female shift workers, such as changing positions frequently during work and implementation of rest breaks and a workplace exercise program, so as to improve worker quality of life.

Is task-shifting a solution to the health workers’ shortage in Northern Ghana?

PubMed Central

Okyere, Eunice; Mwanri, Lillian; Ward, Paul

2017-01-01

Objective To explore the experiences and perceptions of health workers and implementers of task-shifting in rural health facilities in Upper East Region, Ghana. Methods Data was collected through field interviews. A total of sixty eight (68) in-depth interviews were conducted with health workers’ in primary health care facilities (health centres); Four in-depth interviews with key persons involved in staff management was conducted to understand how task-shifting is organised including its strengths and challenges. The health workers interview guide was designed with the aim of getting data on official tasks of health workers, additional tasks assigned to them, how they perceive these tasks, and the challenges associated with the practice of task-shifting. Findings Task-shifting is a practice being used across the health facilities in the study area to help reduce the impact of insufficient health workers. Generally, health workers had a comprehensive training that supported the organisation of task-shifting. However, staff members’ are sometimes engaged in tasks above their level of training and beyond their actual job descriptions. Adequate training is usually not provided before additional tasks are assigned to staff members. Whilst some health workers perceived the additional tasks they performed as an opportunity to learn new skills, others described these as stressful and overburdening. Conclusion Task-shifting has the potential to contribute to addressing the insufficient health workforce, and thereby improving health delivery system where the procedures are well defined and staff members work in a coordinated and organised manner. The provision of adequate training and supervision for health workers is important in order to improve their expertise before additional tasks are assigned to them so that the quality of care would not be compromised. PMID:28358841

The impact of long work hours and shift work on cognitive errors in nurses.

PubMed

Rhéaume, Ann; Mullen, Jane

2018-01-01

Pilot study to examine the impact of long work hours and shift work on cognitive errors in nurses. Twelve-hour shifts are more commonly used in hospital settings and there is growing concern over the impact that extended and irregular work hours have on nurses' well-being and performance. Twenty-eight nurses working different shifts (8-hr days and 12-hr rotation) participated in this study. Nurses were assessed at the beginning of four consecutive shifts using actigraphy, a sleep diary and an after work questionnaire. Nurses working 12-hr rotations had less total sleep time and less sleep efficiency than 8-hr day nurses. Twelve-hour rotation nurses also napped more than their counterparts. There were no differences between the two groups with respect to cognitive errors. Twelve-hour rotations have a negative effect on nurses' sleep patterns. There is no evidence indicating 12-hr rotations increased errors. Nurse managers can implement specific strategies, such as greater shift work flexibility and designated quiet time, to reduce the effects of disturbed sleep patterns in nurses. © 2017 John Wiley & Sons Ltd.

Dietary and lifestyle habits and the associated health risks in shift workers.

PubMed

Nea, Fiona M; Kearney, John; Livingstone, M Barbara E; Pourshahidi, L Kirsty; Corish, Clare A

2015-12-01

Traditionally only a small proportion of the workforce was engaged in shift work. Changing economic pressures have resulted in increased engagement in shift work, with approximately 17 % of the workforce in Europe engaged in this work pattern. The present narrative review aimed to summarise the data on the effects of shift work on the diet, lifestyle and health of employees, while addressing the barriers to, and opportunities for, improving health among shift workers. Shift work can result in low-quality diet and irregular eating patterns. Adverse health behaviours are also reported; particularly increased smoking and poor sleep patterns. These altered lifestyle habits, in conjunction with disruption to circadian rhythms, can create an unfavourable metabolic phenotype which facilitates the development and progression of chronic disease. Although the data are inconclusive due to issues such as poor study design and inadequate control for confounding factors; shift workers appear to be at increased mental and physical health risk, particularly with regard to non-communicable diseases. Information is lacking on the obstacles to leading a healthier lifestyle while working shifts, and where opportunities lie for intervention and health promotion among this group. In order to provide an informed evidence base to assist shift workers in overcoming associated occupational hazards, this gap must be addressed. This review highlights the unique nutritional issues faced by shift workers, and the subsequent effect on health. In societies already burdened with increased incidence of non-communicable chronic diseases, there is a clear need for education and behaviour change interventions among this group.

Differences between day and nonday workers in exposure to physical and psychosocial work factors in the Danish eldercare sector.

PubMed

Nabe-Nielsen, Kirsten; Tüchsen, Finn; Christensen, Karl Bang; Garde, Anne Helene; Diderichsen, Finn

2009-01-01

The possible interaction between individual and occupational risk factors, the need for meaningful intervention, and the demand for valid shift work research make the accumulation of adverse exposures at certain times of the day of special relevance with respect to occupational health. The aim of the present study was therefore to examine whether there was a clustering of detrimental work factors among female eldercare workers in fixed evening or fixed night shifts when they are compared with workers in fixed day shifts. This cross-sectional, questionnaire-based study was conducted among 4590 female health care workers in the Danish eldercare sector. The participants worked in nursing homes, in home care, or in both. They answered questions on job demands, job control, and social support, together with questions on physical and psychological violence, physical workload, and passive smoking. We found that-compared with day workers-fixed nonday workers were more exposed to low job control, low support from leaders, physical and psychological violence, and high physical demands. Nonday workers were, however, less exposed to high demands. These differences remained after control for age, job title, and workplace. Exposures in the work environment of Danish eldercare workers varied between shifts. In a research perspective these findings stress the importance of adequate adjustment for work factors when the health effects of shift work are studied. Moreover, the results underscore the need for an increased awareness of work factors of special importance among nonday workers when interventions against shiftwork-related occupational disorders are designed.

Flexible Schedules and Shift Work.

ERIC Educational Resources Information Center

Beers, Thomas M.

2000-01-01

Flexible work hours have gained prominence, as more than 25 million workers (27.6% of all full-time workers) can now vary their schedules. However, there has been little change since the mid-1980s in the proportion who work a shift other than a regular daytime shift. (JOW)

Some health effects of aircraft noise with special reference to shift work.

PubMed

Rizk, Sanaa A M; Sharaf, Nevin E; Mahdy-Abdallah, Heba; ElGelil, Khalid S Abd

2016-06-01

Aircraft noise is an environmental stressor. A positive relationship exists between noise and high blood pressure. Shift work is an additional hazardous working condition with negative effect on the behavior attitude of workers. This study aimed at investigating some health hazards for shift work on workers at Cairo International Airport (CIA), Egypt, as a strategic work place, with more than one stressor. Assessment of noise effects were carried out in four working sites at the airport besides control sites. The average noise level in the exposure sites was 106.5 dB compared with 54 dB at the control sites. The study comprised a group of 200 male workers exposed to aircraft noise and 110 male workers not exposed to noise as control group. All workers had full general medical examination after filling specially formulated questionnaire. Hearing impairment, raised blood pressure, headaches, disturbed sleep, and symptoms of anxiety were more prominent among the exposed workers than the control. Symptoms of upper respiratory tract were reported among night shifters of both groups with high tendency for smoking. Thus, night-shift workers at CIA work under more than one stressor. Hypertension and smoking might act as intermediate factors on the causal pathway of complaints, making aircraft noise and night shift acting as two synergistic stressors. Airport workers are in need for aggressive hearing conservation programs. Organization of the working hours schedule is mandatory to avoid excessive noise exposure. © The Author(s) 2014.

Employer differences in upper-body musculoskeletal disorders and pain among immigrant Latino poultry processing workers.

PubMed

Rosenbaum, Daryl A; Mora, Dana C; Arcury, Thomas A; Chen, Haiying; Quandt, Sara A

2014-01-01

Between-employer differences in working conditions may lead to variable injury rates. The objective of this paper is to assess the difference in the prevalence of epicondylitis, rotator cuff syndrome, and low back pain among immigrant Latino poultry workers at plants of three different employers. Data were collected from a cross-sectional study among 286 poultry processing workers. Community-based sampling was used to recruit participants in western North Carolina. Rotator cuff syndrome (26.7%) and low back pain (27.9%) were more prevalent among employees of one specific employer. Multivariate analysis showed significant associations of low back pain and rotator cuff syndrome with age, task performed in the processing line, and employer. Employer is a major predictor of musculoskeletal disorders and pain. Line speed and work pace may account for these differences and provide an opportunity for regulation and intervention to protect the health of workers.

Association between shift work history and performance on the trail making test in middle-aged and elderly humans: the EpiHealth study.

PubMed

Titova, Olga E; Lindberg, Eva; Elmståhl, Sölve; Lind, Lars; Schiöth, Helgi B; Benedict, Christian

2016-09-01

Shift work has been proposed to promote cognitive disturbances in humans; however, conflicting evidence is also present. By using data from 7143 middle-aged and elderly humans (45-75 years) who participated in the Swedish EpiHealth cohort study, the present analysis sought to investigate whether self-reported shift work history would be associated with performance on the trail making test (TMT). The TMT has been proposed to be a useful neuropsychological tool to evaluate humans' executive cognitive function, which is known to decrease with age. After adjustment for potential confounders (e.g., age, education, and sleep duration), it was observed that current and recent former shift workers (worked shifts during the past 5 years) performed worse on the TMT than nonshift workers. In contrast, performance on the TMT did not differ between past shift workers (off from shift work for more than 5 years) and nonshift workers. Collectively, our results indicate that shift work history is linked to poorer performance on the TMT in a cohort of middle-aged and elderly humans. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Biomechanical Effects of Capsular Shift in the Treatment of Hip Microinstability: Creation and Testing of a Novel Hip Instability Model.

PubMed

Jackson, Timothy J; Peterson, Alexander B; Akeda, Masaki; Estess, Allyson; McGarry, Michelle H; Adamson, Gregory J; Lee, Thay Q

2016-03-01

A capsular shift procedure has been described for the treatment of hip instability; however, the biomechanical effects of such a shift are unknown. To create a cadaveric model of hip capsule laxity and evaluate the biomechanical effects of a capsular shift used to treat hip instability on this model. Controlled laboratory study. Eight cadaveric hips with an average age of 58.5 years were tested with a custom hip testing system in 6 conditions: intact, vented, instability, capsulotomy, side-to-side repair, and capsular shift. To create the hip model, the capsule was stretched in extension under 35 N·m of torque for 1 hour in neutral rotation. Measurements included internal and external rotation with 1.5 N·m of torque at 5 positions: 5° of extension and 0°, 15°, 30°, and 45° of flexion for each of the above conditions. The degree of maximum extension with 5 N·m of torque and the amount of femoral distraction with 40 N and 80 N of force were measured. Statistical analysis was performed by use of repeated-measures analysis of variance with Tukey post hoc analysis. The instability state significantly increased internal rotation at all flexion angles and increased distraction compared with the intact state. The capsulotomy condition resulted in significantly increased external rotation and internal rotation at all positions, increased distraction, and maximum extension compared with the intact state. The side-to-side repair condition restored internal rotation back to the instability state but not to the intact state at 5° of extension and 0° of flexion. The capsular shift state significantly decreased internal rotation compared with the instability state at 5° of extension and 0° and 15° of flexion. The capsular shift and side-to-side repair conditions had similar effects on external rotation at all flexion-extension positions. The capsular shift state decreased distraction and maximum extension compared with the instability state, but the side-to-side repair state did not. The hip capsular instability model was shown to have significantly greater total range of motion, external rotation, and extension compared with the intact condition. The greatest effects of capsular shift are seen with internal rotation, maximum extension, and distraction, with minimal effect on external rotation compared with the side-to side repair state. The biomechanical effects of the capsular shift procedure indicate that it can be used to treat hip capsular laxity by decreasing extension and distraction with minimal effect on external rotation. © 2015 The Author(s).

Measurement of Small Optical Polarization Rotations

ERIC Educational Resources Information Center

Kraftmakher, Yaakov

2009-01-01

When data with and without an optically active sample are acquired simultaneously while one manually rotates the analyser, the graph of the first signal versus the second one is an ellipse whose shape shows the phase shift between the two signals; this shift is twice the optical rotation. There is no need to measure the rotation of the analyser or…

The Effect of Shift Work on Urogenital Disease: a Systematic Review.

PubMed

Deng, Nanfu; Haney, Nora M; Kohn, Taylor P; Pastuszak, Alexander W; Lipshultz, Larry I

2018-05-28

Non-standard shift work schedules negatively impact the overall health of shift workers, and several studies have shown that shift work, specifically, is detrimental to urogenital health. The aims of this study are to systematically review the literature and determine the effect of shift work on the outcomes of hypogonadism, male infertility, lower urinary tract symptoms, and urogenital cancers. Recent evidence supports associations between non-standard shift work and an increase in the frequency of prostate cancer and the severity of erectile dysfunction, lower urinary tract symptoms, and hypogonadal symptoms, as well as worsening of semen parameters and fertility. These associations are strengthened by the presence of shift work sleep disorder (SWSD) which affects up to 20% of shift workers. No studies have assessed the impact of shift work on the frequency or severity of nephrolithiasis, interstitial cystitis, pelvic pain, prostatitis, or urinary tract infections. Non-standard shift work has been associated with a variety of negative health outcomes and urologic complications, especially with concurrent shift work sleep disorder. Recognition of these elevated risks among shift workers can aid in more effective screening for urologic conditions.

A Community Health Worker-Led Rotation to Train Medical Students in the Social Determinants of Health.

PubMed

Kangovi, Shreya; Carter, Tamala; Smith, Robyn A; DeLisser, Horace M

2018-01-01

Medical students often lack training in understanding and addressing the social determinants that shape the health of high-risk populations. We describe a novel clinical elective rotation in which fourth-year medical students served as apprentices to community health workers in order to develop community engagement skills and cultural humility.

Health behaviours and outcomes associated with fly-in fly-out and shift workers in Western Australia.

PubMed

Joyce, S J; Tomlin, S M; Somerford, P J; Weeramanthri, T S

2013-04-01

To examine the association of health behaviours and outcomes with employment type in the West Australian adult population. Cross-sectional study of employed adults aged 16 years and over using self-reported information collected in the WA Health and Wellbeing Surveillance System between 2008 and 2010. A total of 380 fly-in fly-out (FIFO) workers, 913 shift workers and 10 613 workers of other employment types were identified. FIFO workers exhibited similar health behaviours to shift workers but had a different sociodemographic profile. Compared with other employment types, FIFO workers were significantly more likely to be current smokers, drink alcohol at risky levels, and be overweight or obese, after adjusting for age, sex and survey sampling strategies. They were less likely to report current mental health problems. Self-reported health behaviours of FIFO workers differ from other employment types. FIFO workers are expected to increase in number over the next decade, as the mining and resources sector expands in Australia. Our findings suggest that health interventions, whether in the workplace or clinical settings, need to be informed by the demographic mix of the cohort of workers on entry as they are not a homogenous group, and targeted towards specific employment patterns (length of shifts and type of employment) to improve their current and future well-being. © 2012 The Authors; Internal Medicine Journal © 2012 Royal Australasian College of Physicians.

Exposure of hospitality workers to environmental tobacco smoke

PubMed Central

Bates, M; Fawcett, J; Dickson, S; Berezowski, R; Garrett, N

2002-01-01

Objective: To determine quantitatively the extent of exposure of hospitality workers to environmental tobacco smoke (ETS) exposure during the course of a work shift, and to relate these results to the customer smoking policy of the workplace. Subjects: Three categories of non-smoking workers were recruited: (1) staff from hospitality premises (bars and restaurants) that permitted smoking by customers; (2) staff from smokefree hospitality premises; and (3) government employees in smokefree workplaces. All participants met with a member of the study team before they began work, and again at the end of their shift or work day. At each meeting, participants answered questions from a standardised questionnaire and supplied a saliva sample. Main outcome measures: Saliva samples were analysed for cotinine. The difference between the first and second saliva sample cotinine concentrations indicated the degree of exposure to ETS over the course of the work shift. Results: Hospitality workers in premises allowing smoking by customers had significantly greater increases in cotinine than workers in smokefree premises. Workers in hospitality premises with no restrictions on customer smoking were more highly exposed to ETS than workers in premises permitting smoking only in designated areas. Conclusions: Overall, there was a clear association between within-shift cotinine concentration change and smoking policy. Workers in premises permitting customer smoking reported a higher prevalence of respiratory and irritation symptoms than workers in smokefree workplaces. Concentrations of salivary cotinine found in exposed workers in this study have been associated with substantial involuntary risks for cancer and heart disease. PMID:12035005

Increased errors and decreased performance at night: A systematic review of the evidence concerning shift work and quality.

PubMed

de Cordova, Pamela B; Bradford, Michelle A; Stone, Patricia W

2016-02-15

Shift workers have worse health outcomes than employees who work standard business hours. However, it is unclear how this poorer health shift may be related to employee work productivity. The purpose of this systematic review is to assess the relationship between shift work and errors and performance. Searches of MEDLINE/PubMed, EBSCOhost, and CINAHL were conducted to identify articles that examined the relationship between shift work, errors, quality, productivity, and performance. All articles were assessed for study quality. A total of 435 abstracts were screened with 13 meeting inclusion criteria. Eight studies were rated to be of strong, methodological quality. Nine studies demonstrated a positive relationship that night shift workers committed more errors and had decreased performance. Night shift workers have worse health that may contribute to errors and decreased performance in the workplace.

Night-shift work and risk of compromised visual acuity among the workers in an electronics manufacturing company.

PubMed

Lin, Yu-Cheng; Ho, Kuo-Jung

2018-01-01

To evaluate the association between night-shift work exposure and visual health, this cross-sectional study utilized visual acuity, a surrogate measure for visual function, as a parameter, and performed an analysis comparing visual acuity between daytime and nighttime employees in an electronics manufacturing company. Data of personal histories, occupational records, physical examinations and blood tests was obtained from the electronic health records of workers. The total of 8280 workers including 3098 women and 5182 men, wearing their own daily used eyeglasses, were included in the final analysis. The mean age of the sample population was 34.7 years old (standard deviation = 5.4 years). All workers were divided into 3 work categories - consistent daytime worker (CDW), day-shift worker (DSW) and night-shift worker (NSW). The check-up results of glasses-corrected visual acuity (c-VA) were utilized to classify individuals as good (≥ 1.2, both eyes) and inadequate (< 0.8, the better eye) c-VA. Consistent daytime workers had the highest rate of good c-VA (42.5% vs. 25.1% DSW and 21.1% NSW, p = 0.047). Night-shift workers had the highest rate of inadequate c-VA (CDW, DSW and NSW: 2.6%, 6.2%, and 7.6%, p = 0.03) among all employees. After controlling for covariates, NSW were found at an increased risk for inadequate c-VA (adjusted odds ratio (ORa) = 2.7, 95% confidence interval (CI): 2.0-3.6, vs. CDW), and less likely to have good c-VA (ORa = 0.4, 95% CI: 0.4-0.5, vs. CDW). Night-shift work is moderately associated with compromised visual acuity of employees in this electronics manufacturing company. Int J Occup Med Environ Health 2018;31(1):71-79. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Development and psychometric evaluation of a women shift workers' reproductive health questionnaire: study protocol for a sequential exploratory mixed-method study.

PubMed

Nikpour, Maryam; Tirgar, Aram; Ebadi, Abbas; Ghaffari, Fatemeh; Firouzbakht, Mojgan; Hajiahmadi, Mahmod

2018-02-06

Although shift works is a certain treat for female reproductive health, but currently, there is no standardized instrument for measuring reproductive health among female shift workers. This study aims to develop and evaluate the psychometric properties of a Women Shift Workers' Reproductive Health Questionnaire (WSW-RHQ). This is a sequential exploratory mixed-method study with a qualitative and a quantitative phase. In the qualitative phase, semi-structured interviews will be held with female shift workers who live in Mazandaran Province, Iran, additionally, the literature review will be performed by searching electronic databases. Sampling will be done in different workplaces and with maximum variation respecting female shift workers' age and job and educational and different economic situation. Interview data will be analyzed using conventional content analysis and then, the primary item pool for the questionnaire will be developed. In the quantitative phase, we will evaluate the psychometric properties of the questionnaire, i.e. its face, content, construct as well as reliability via the internal consistency, stability. Finally, a scoring system will be developed for the questionnaire. The development of WSW-RHQ will facilitate the promotion and implementation of reproductive health interventions and assessment of their effectiveness. Other scholars can cross-culturally adapt and use the questionnaire according to their immediate contexts.

Pixel-based absolute surface metrology by three flat test with shifted and rotated maps

NASA Astrophysics Data System (ADS)

Zhai, Dede; Chen, Shanyong; Xue, Shuai; Yin, Ziqiang

2018-03-01

In traditional three flat test, it only provides the absolute profile along one surface diameter. In this paper, an absolute testing algorithm based on shift-rotation with three flat test has been proposed to reconstruct two-dimensional surface exactly. Pitch and yaw error during shift procedure is analyzed and compensated in our method. Compared with multi-rotation method proposed before, it only needs a 90° rotation and a shift, which is easy to carry out especially in condition of large size surface. It allows pixel level spatial resolution to be achieved without interpolation or assumption to the test surface. In addition, numerical simulations and optical tests are implemented and show the high accuracy recovery capability of the proposed method.

Respiratory effects among rubberwood furniture factory workers in Thailand.

PubMed

Sriproed, Salakjit; Osiri, Pramuk; Sujirarat, Dusit; Chantanakul, Suttinun; Harncharoen, Kitiphong; Ong-artborirak, Parichat; Woskie, Susan R

2013-01-01

Respiratory symptoms and pulmonary function were examined among 89 rubberwood furniture factory workers. Acute and chronic irritant symptoms were assessed, lung function was measured both pre- and post-shift and personal inhalable dust exposure determined. The only symptoms with a significant increase among high dust level-exposed workers (>1 mg/m(3)) were those related to nasal irritation. High dust level-exposed workers had a significant cross-shift decrease in forced expiratory volume in 1 second/forced vital capacity (FEV(1)/FVC) compared with low dust level-exposed workers and increases in inhalable dust concentration levels (mg/m(3)) were significantly associated with decreases in the peak expiratory flow (PEF) across the work shift. For percent predicted pulmonary function levels, a significant decrement in PEF was found for high versus low rubberwood dust level-exposed workers, after controlling for confounders. These findings suggest the need for an occupational standard for rubberwood dust in Thailand.

Analysis of the workload imposed on the workers of the imprint and cutting/welding sectors of a flexible packaging manufacturer.

PubMed

de M Guimarães, L B; Pessa, S L R; Biguelini, C

2012-01-01

This article presents a study on the evaluation of the workload imposed to workers of two sectors of a flexible packaging manufacturer that operates in three shifts. The workers are allocated in one of the shifts (morning, evening and night shifts) without evaluation of their chronotype and/or social needs. The Imprint sector has a more dynamic work, which is done only by man due to the effort demanded by handling loads. The work in the Cutting/Welding sector is static, done mainly by women. The results showed that the overall workload was the same in the Imprint and Cutting/Welding sectors, because physical effort for load handling is higher in the former but the latter involves high static load. The levels of urinary catecholamines and salivary cortisol were consistent with the workers biological clock showing that none of the workers changed his/her biological cycle to accommodate to the time of the shift schedule.

Working the night shift causes increased vascular stress and delayed recovery in young women.

PubMed

Lo, Shih-Hsiang; Lin, Lian-Yu; Hwang, Jing-Shiang; Chang, Yu-Yin; Liau, Chiau-Suong; Wang, Jung-Der

2010-08-01

Shiftwork has been associated with elevated blood pressure (BP) and decreased heart-rate variability (HRV), factors that may increase the long-term risk of cardiovascular-related mortality and morbidity. This study explored the effect of shiftwork on dynamic changes in autonomic control of HRV (cardiac stress), systolic BP and diastolic BP, i.e., SBP and DBP (vascular stress), and recovery in the same subjects working different shifts. By studying the same subjects, the authors could reduce the effect of possible contribution of between-subject variation from genetic predisposition and environmental factors. The authors recruited 16 young female nurses working rotating shifts--day (08:00-16:00 h), evening (16:00-00:00 h), and night (00:00-08:00 h)--and 6 others working the regular day shift. Each nurse received simultaneous and repeated 48-h ambulatory electrocardiography and BP monitoring during their work day and the following off-duty day. Using a linear mixed-effect model to adjust for day shift, the results of the repeated-measurements and self-comparisons found significant shift differences in vascular stress. While working the night shift, the nurses showed significant increases in vascular stress, with increased SBP of 9.7 mm Hg. The changes of SBP and DBP seemed to peak during waking time at the same time on the day off as they did on the working day. Whereas HRV profiles usually returned to baseline level after each shift, the SBP and DBP of night-shift workers did not completely return to baseline levels the following off-duty day (p < .001). The authors concluded that although the nurses may recover from cardiac stress the first day off following a night shift, they do not completely recover from increases in vascular stress on that day.

Evaluation of respiratory system in textile-dyeing workers.

PubMed

Salmani Nodoushan, Mojahede; Mehrparvar, Amir Houshang; Loukzadeh, Ziba; Rahimian, Masoud; Ghove Nodoushan, Mohamad Ali; Jafari Nodoushan, Reza

2014-01-01

Despite the presence of many textile and dyeing plants in Iran, we couldn't find similar studies in this country. Forthermore, considering progress in the dyeing process and engineering controls, assessment of respiratory system is important for these workers. The present study was performed to evaluate the respiratory system in dyeing workers. In a cross-sectional study, 101 dyeing workers (all dyeing workers in yazd) and 90 workers without respiratory exposures (control group), were evaluated. A questionnaire was filled for each participant included Venables questionnaire and some other questions about age, work experience, personal or familial history of asthma or atopy, acute and chronic respiratory symptoms; Then spirometry was performed before and after the shift work Results: The frequency of acute and chronic respiratory symptoms was significantly higher among dyeing workers than controls. According to the Venables questionnaire, 11.9% of the dyeing workers suffered from asthma. Means of FVC and FEV1 of pre-shift spirometry were lower than control (p< 0.001). Across-shift spirometry showed significant reduction of FVC (p< 0.001), FEV1 (p< 0.001), FEF25-75% (p= 0.05) and FEF25% (p= 0.007) in dyeing workers compared to the control group. Evaluation of dyeing workers' respiratory system in this study showed that despite development in dyeing processes and engineering controls, workers in this job show more prevalent acute and chronic symptoms, and across-shift changes in spirometric parameters were significantly higher in this work group than the control group. Therefore it is necessary to pay attention to the control of respiratory exposures in this job.

Changes in working time arrangements over time as a consequence of work-family conflict.

PubMed

Jansen, Nicole W H; Mohren, Danielle C L; van Amelsvoort, Ludovic G P M; Janssen, Nathalie; Kant, Ijmert

2010-07-01

Existing longitudinal studies on the relationship between working time arrangements (WTA) and work-family conflict have mainly focused on the normal causal relationship, that is, the impact of WTA on work-family conflict over time. So far, however, the reversed relationship, that is, the effect of work-family conflict on adjustments in WTA over time, has hardly been studied. Because work-family conflict is highly prevalent in the working population, further insight in this reverse relationship is invaluable to gain insight into secondary selection processes. The aim of this study is to investigate whether work-family conflict is prospectively related to adjustments in work schedules, working hours, and overtime work, and to explore sex differences and different time lags in this relation. Data of the prospective Maastricht Cohort Study were used. To study the effect of work-family conflict on a change from shift- to day work over 32 months of follow-up, male three-shift (n = 727), five-shift (n = 932), and irregular-shift (n = 451) workers were selected. To study effects of work-family conflict on reduction of working hours over 12 and 24 months of follow-up, respectively, only day workers (males and females) were selected, capturing 5809 full-time workers (> or =36 h/wk) and 1387 part-time workers (<36 h/wk) at baseline. To examine effects of work-family conflict on refraining from overtime work over 12 months of follow-up, only day workers reporting frequent overtime work at baseline were selected (3145 full-time and 492 part-time workers). Cox regression analyses were performed with adjustments for age, educational level, and presence of a long-term illness. Work-family conflict was associated with a significantly increased risk of changing from shift- to day work over 32 months of follow-up in three-shift workers (relative risk [RR] = 1.77, 95% confidence interval [CI] 1.19-2.63) but not in five-shift workers (RR = 1.32, 95% CI 0.78-2.24) and irregular-shift workers (RR = 0.81, 95% CI 0.50-1.31). Within day workers, work-family conflict among full-time workers was associated with a significantly increased risk of reducing working hours during 1 yr of follow-up in women (RR = 2.80, 95% CI 1.42-5.54) but not men (RR = 1.34, 95% CI 0.81-2.22). In part-time workers, work-family conflict was associated with a significantly increased risk of reducing working hours during 1 yr of follow-up both in women (RR = 1.99, 95% CI 1.04-3.82) and men (RR = 4.03, 95% CI 1.28-12.68). Whereas the effects of work-family conflict on a reduction of working hours somewhat decreased among female full-time workers after 2 yr of follow-up (RR = 2.13, 95% CI 1.24-3.66), among male full-time workers the effects increased and reached statistical significance (RR = 1.53, 95% CI 1.05-2.21). Work-family conflict was not significantly associated with refraining from overtime work over 1 yr of follow-up. This study shows that work-family conflict has important consequences in terms of adjustments in work schedules and working hours over time, with considerable sex differences. The study thereby clearly illustrates secondary selection processes both in shift- and day workers, with significant implications for labor force participation, emphasizing the need for prevention of work-family conflict.

Relationship between sleeping on the night shift and recovery from work among nursing workers - the influence of domestic work.

PubMed

Silva-Costa, Aline; Rotenberg, Lúcia; Griep, Rosane Harter; Fischer, Frida Marina

2011-05-01

This paper is a report of a study on the association between sleep patterns during work nights and recovery from work among nursing workers, considering domestic work hours. Several hospitals allow nursing workers to sleep during the night shift, but this is rarely evaluated from the workers' health perspective. The need for recovery from work concept can be useful for testing the impact of night work on sleep. Recovery is not a problem if workers have enough time to recover between periods of work. Therefore, domestic work would be likely to interfere in the recovery process. This cross-sectional study was carried out at three hospitals in 2005-2006, through a comprehensive questionnaire. All nursing teams engaged in assistance to patients were invited to participate. Analyses included female night workers with no incidence of insomnia. Participants (n = 396) were classified into those who did not sleep during night shifts, those who slept for up to 2 hours and those who slept for 2-3 hours. Binomial logistic regression analysis showed that sleeping on the job for 2-3 hours during night shifts is related to a better recovery from work provided the workers do not undergo long domestic work hours. Being allowed to sleep at work during night shifts seemed to contribute to, but was not enough to guarantee, a good recovery from work in the studied population. Recommendations to deal with sleep-deprivation among night workers should consider the complexity of gender roles on the recovery process. © 2011 Blackwell Publishing Ltd.

Shift Workers: A Descriptive Analysis of Worker Characteristics.

ERIC Educational Resources Information Center

Medley, Carol

National Longitudinal Surveys of Labor Force Experience (NLS) data were used to describe those people who work outside the traditional 9:00 A.M. to 5:00 P.M. work day. Depending on the approximate time of day they worked, respondents were classified into four categories of workers: day, evening, night, and split shift (working hours interrupted by…

Circadian and ultradian rhythms in the feeding behaviour and nutrient intakes of oil refinery operators with shift-work every 3--4 days.

PubMed

Reinberg, A; Migraine, C; Apfelbaum, M; Brigant, L; Ghata, J; Vieux, N; Laporte, A; Nicolai

1979-03-01

Seven healthy adult men, five shift-workers and two non-shift-workers (from 21 to 36 years; mean = 26.4) volunteered to record what and when they ate, both at work and at home, every day, during eight consecutive weeks (Oct. - Dec. 1974). 1) All the subjects maintained the timing of main-meal (lunch and supper) during all shifts. 2) The major intake of protein and lipid was concentrated on the two main meals during all shifts. 3) Only the pattern of carbohydrate intake was modified by the shift-work: e.g. night-shift is associated with nibbling behaviour. 4) However, shift-work and in particular the occurence of nibbling behaviour did not result in change either in the mean 24 h caloric intake, or in the percentage of protein calories. 5) The comparison between the constancy of the timing of major meals and the shift of the timing of circadian rhythm acrophases of the 5 shift-workers leads to conclude that meal timing had a poor synchronizing effect, if any.

Work environment of Danish shift and day workers.

PubMed

Bøggild, H; Burr, H; Tüchsen, F; Jeppesen, H J

2001-04-01

Both shift work and other work environment factors have been shown to be related to heart disease. This study examined whether shift work is associated with other work environment factors related to heart disease in a random sample of the population. If so, shift work could be acting as a proxy for work environment differences. Data on 5940 employees in the Danish Work Environment Cohort Study from 1990 were reanalyzed. The information included work schedules [permanent day work, irregular workhours (including morning work), 2-shift or fixed evening and 3-shift or fixed night], length of workweek, physical factors (noise, heat, dust, passive smoking, walking, standing and monotonous repetitive tasks), and psychosocial factors (including demands and control dimensions, social support, conflicts and job insecurity). At least 1 group of shift workers had a higher prevalence of nearly every unfavorable work environment factor investigated. Exceptions were dust exposure and quantitative demands. Especially conflicts at work and low decision latitude were higher among all the groups of shift workers, and all-day walking or standing work and part-time jobs were more often found among female shift workers. The 3 different shiftwork groups were exposed to different parts of the work environment, and also men and women in shift work differed in relation to the work environment. Age and social class influenced the relationship, but not in any particular pattern. In a heterogenous population shift work was found to be associated with other work environment factors suspected to cause heart disease.

The rotate-plus-shift C-arm trajectory. Part I. Complete data with less than 180° rotation.

PubMed

Ritschl, Ludwig; Kuntz, Jan; Fleischmann, Christof; Kachelrieß, Marc

2016-05-01

In the last decade, C-arm-based cone-beam CT became a widely used modality for intraoperative imaging. Typically a C-arm CT scan is performed using a circular or elliptical trajectory around a region of interest. Therefore, an angular range of at least 180° plus fan angle must be covered to ensure a completely sampled data set. However, mobile C-arms designed with a focus on classical 2D applications like fluoroscopy may be limited to a mechanical rotation range of less than 180° to improve handling and usability. The method proposed in this paper allows for the acquisition of a fully sampled data set with a system limited to a mechanical rotation range of at least 180° minus fan angle using a new trajectory design. This enables CT like 3D imaging with a wide range of C-arm devices which are mainly designed for 2D imaging. The proposed trajectory extends the mechanical rotation range of the C-arm system with two additional linear shifts. Due to the divergent character of the fan-beam geometry, these two shifts lead to an additional angular range of half of the fan angle. Combining one shift at the beginning of the scan followed by a rotation and a second shift, the resulting rotate-plus-shift trajectory enables the acquisition of a completely sampled data set using only 180° minus fan angle of rotation. The shifts can be performed using, e.g., the two orthogonal positioning axes of a fully motorized C-arm system. The trajectory was evaluated in phantom and cadaver examinations using two prototype C-arm systems. The proposed trajectory leads to reconstructions without limited angle artifacts. Compared to the limited angle reconstructions of 180° minus fan angle, image quality increased dramatically. Details in the rotate-plus-shift reconstructions were clearly depicted, whereas they are dominated by artifacts in the limited angle scan. The method proposed here employs 3D imaging using C-arms with less than 180° rotation range adding full 3D functionality to a C-arm device retaining both handling comfort and the usability of 2D imaging. This method has a clear potential for clinical use especially to meet the increasing demand for an intraoperative 3D imaging.

The rotate-plus-shift C-arm trajectory. Part I. Complete data with less than 180° rotation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ritschl, Ludwig; Fleischmann, Christof; Kuntz, Jan, E-mail: j.kuntz@dkfz.de

Purpose: In the last decade, C-arm-based cone-beam CT became a widely used modality for intraoperative imaging. Typically a C-arm CT scan is performed using a circular or elliptical trajectory around a region of interest. Therefore, an angular range of at least 180° plus fan angle must be covered to ensure a completely sampled data set. However, mobile C-arms designed with a focus on classical 2D applications like fluoroscopy may be limited to a mechanical rotation range of less than 180° to improve handling and usability. The method proposed in this paper allows for the acquisition of a fully sampled datamore » set with a system limited to a mechanical rotation range of at least 180° minus fan angle using a new trajectory design. This enables CT like 3D imaging with a wide range of C-arm devices which are mainly designed for 2D imaging. Methods: The proposed trajectory extends the mechanical rotation range of the C-arm system with two additional linear shifts. Due to the divergent character of the fan-beam geometry, these two shifts lead to an additional angular range of half of the fan angle. Combining one shift at the beginning of the scan followed by a rotation and a second shift, the resulting rotate-plus-shift trajectory enables the acquisition of a completely sampled data set using only 180° minus fan angle of rotation. The shifts can be performed using, e.g., the two orthogonal positioning axes of a fully motorized C-arm system. The trajectory was evaluated in phantom and cadaver examinations using two prototype C-arm systems. Results: The proposed trajectory leads to reconstructions without limited angle artifacts. Compared to the limited angle reconstructions of 180° minus fan angle, image quality increased dramatically. Details in the rotate-plus-shift reconstructions were clearly depicted, whereas they are dominated by artifacts in the limited angle scan. Conclusions: The method proposed here employs 3D imaging using C-arms with less than 180° rotation range adding full 3D functionality to a C-arm device retaining both handling comfort and the usability of 2D imaging. This method has a clear potential for clinical use especially to meet the increasing demand for an intraoperative 3D imaging.« less

Minor mental disorders in Taiwanese healthcare workers and the associations with psychosocial work conditions.

PubMed

Cheng, Wan-Ju; Cheng, Yawen

2017-04-01

Healthcare workers face multiple psychosocial work hazards intrinsic to their work, including heavy workloads and shift work. However, how contemporary adverse psychosocial work conditions, such as workplace justice and insecurity, may contribute to increased mental health risks has rarely been studied. This study aimed to search for modifiable psychosocial work factors associated with mental health disorders in Taiwanese healthcare workers. A total of 349 healthcare workers were identified from 19,641 employees who participated in a national survey of Taiwan. Minor mental disorder was assessed using the five-item brief symptom rating scale. We compared psychosocial work characteristics and the prevalence of minor mental disorder in healthcare workers with that in a sociodemographically matched sample, and examined the associations of psychosocial work conditions with mental health status. Healthcare workers were found to have a higher prevalence of minor mental disorder than general workers, and they were more likely to have longer working hours, heavier psychological job demands, higher job control, more workplace violence, and a higher prevalence of shift work. Among healthcare workers, experiences of workplace violence, lower workplace justice, heavier psychological job demands, and job insecurity were associated with a higher risk for minor mental disorder, even after controlling for working hours and shift work. Despite the fact that healthcare workers work longer hours and shift work, there were several modifiable psychosocial work conditions that should be targeted to improve their mental health. Copyright © 2016. Published by Elsevier B.V.

Metabolic syndrome in fixed-shift workers.

PubMed

Canuto, Raquel; Pattussi, Marcos Pascoal; Macagnan, Jamile Block Araldi; Henn, Ruth Liane; Olinto, Maria Teresa Anselmo

2015-01-01

OBJECTIVE To analyze if metabolic syndrome and its altered components are associated with demographic, socioeconomic and behavioral factors in fixed-shift workers. METHODS A cross-sectional study was conducted on a sample of 902 shift workers of both sexes in a poultry processing plant in Southern Brazil in 2010. The diagnosis of metabolic syndrome was determined according to the recommendations from Harmonizing the Metabolic Syndrome. Its frequency was evaluated according to the demographic (sex, skin color, age and marital status), socioeconomic (educational level, income and work shift), and behavioral characteristics (smoking, alcohol intake, leisure time physical activity, number of meals and sleep duration) of the sample. The multivariate analysis followed a theoretical framework for identifying metabolic syndrome in fixed-shift workers. RESULTS The prevalence of metabolic syndrome in the sample was 9.3% (95%CI 7.4;11.2). The most frequently altered component was waist circumference (PR 48.4%; 95%CI 45.5;51.2), followed by high-density lipoprotein. Work shift was not associated with metabolic syndrome and its altered components. After adjustment, the prevalence of metabolic syndrome was positively associated with women (PR 2.16; 95%CI 1.28;3.64), workers aged over 40 years (PR 3.90; 95%CI 1.78;8.93) and those who reported sleeping five hours or less per day (PR 1.70; 95%CI 1.09;2.24). On the other hand, metabolic syndrome was inversely associated with educational level and having more than three meals per day (PR 0.43; 95%CI 0.26;0.73). CONCLUSIONS Being female, older and deprived of sleep are probable risk factors for metabolic syndrome, whereas higher educational level and higher number of meals per day are protective factors for metabolic syndrome in fixed-shift workers.

Acute suppression of serum IgM and IgA in tank workers exposed to benzene.

PubMed

Kirkeleit, J; Ulvestad, E; Riise, T; Bråtveit, M; Moen, B E

2006-12-01

We investigated associations between benzene exposure and alterations of proteins and cells of the immune system among workers maintaining cargo tanks containing crude oil residues. Individual exposure to benzene, benzene in blood and urine, peripheral blood lymphocytes (total lymphocytes, lymphocytes in subpopulations CD3, CD4, CD8, CD19, CD56 and CD4/CD8 ratio), complement factors C3 and C4 and serum concentration of immunoglobulins (IgG, IgA, IgM and IgE) were analysed among 13 tank workers and nine unexposed referents (catering section). Benzene exposure was measured during three consecutive 12-h work days. Blood and urine samples were collected pre-shift on the first day (baseline), post-shift on the third day, and pre-next shift on the following morning. The time spent in the cargo tank was logged. The individual geometric mean benzene exposure in the breathing zone of tank workers over 3 days was 0.15 p.p.m. (range 0.01-0.62 p.p.m.) (n = 26). The geometric mean benzene concentration in blood post-shift was 12.3 nmol/l among tank workers versus 0.7 nmol/l among the referents. Tank workers showed a decline (versus referents) in IgM from baseline to post-shift (t-test, P = 0.04) and IgA from baseline to pre-next shift (t-test, P = 0.01). They also showed a decline in CD4 T cells from baseline to post-shift (t-test, P = 0.04). Suppression correlated with benzene exposure, benzene concentrations in blood and urine and time spent in the tank. The groups did not differ significantly in the change in other immune parameters. The clinical significance is unknown and warrants further studies.

Nutrition and health in hotel staff on different shift patterns.

PubMed

Seibt, R; Süße, T; Spitzer, S; Hunger, B; Rudolf, M

2015-08-01

Limited research is available that examines the nutritional behaviour and health of hotel staff working alternating and regular shifts. To analyse the nutritional behaviour and health of employees working in alternating and regular shifts. The study used an ex post facto cross-sectional analysis to compare the nutritional behaviour and health parameters of workers with alternating shifts and regular shift workers. Nutritional behaviour was assessed with the Food Frequency Questionnaire. Body dimensions (body mass index, waist hip ratio, fat mass and active cell mass), metabolic values (glucose, triglyceride, total cholesterol and low- and high-density lipoprotein), diseases and health complaints were included as health parameters. Participants worked in alternating (n = 53) and regular shifts (n = 97). The average age of subjects was 35 ± 10 years. There was no significant difference in nutritional behaviour, most surveyed body dimensions or metabolic values between the two groups. However, alternating shift workers had significantly lower fat mass and higher active cell mass but nevertheless reported more pronounced health complaints. Sex and age were also confirmed as influencing the surveyed parameters. Shift-dependent nutritional problems were not conspicuously apparent in this sample of hotel industry workers. Health parameters did not show significantly negative attributes for alternating shift workers. Conceivably, both groups could have the same level of knowledge on the health effects of nutrition and comparable opportunities to apply this. Further studies on nutritional and health behaviour in the hotel industry are necessary in order to create validated screening programmes. © The Author 2015. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effect of time of day and duration into shift on hazardous exposures to biological fluids.

PubMed

Macias, D J; Hafner, J; Brillman, J C; Tandberg, D

1996-06-01

To determine whether hospital employee biological hazardous exposure rates varied with time of day or increased with time interval into shift. This was a retrospective occurrence report review conducted at a university hospital with an emergency medicine residency program. Health care worker biological hazardous exposure data over a 30-month period were reviewed. Professional status, date, time, and type of exposure (needlestick, laceration, splash), time interval into shift of exposure, and hospital location of exposure were recorded. Hourly employee counts and risky procedure counts were matched by location with each reported exposure, to determine hourly rates of biological hazardous exposures. Analysis of 411 recorded exposures demonstrated that more people were exposed between 9:00 AM and 11:00 AM (p < 0.05), yet the exposure risk did not vary significantly when expressed as the number of exposures per worker or per procedure. Of the 393 exposures with data describing time interval into shift when the exposure occurred, significant numbers of exposures occurred during the first hour and at shift's end [when corrected for exposures per worker (p < 0.05) or exposures per procedure (p < 0.05)]. While the number of exposures are increased in the AM hours, the exposure rate (as a function of workers or procedures) does not vary with time of the day. However, the exposure rate is increased during the first hour and last 2 hours of a shift. Efforts to increase worker precautions at the beginning and end of shifts are warranted.

Perceptions of health stakeholders on task shifting and motivation of community health workers in different socio demographic contexts in Kenya (nomadic, peri-urban and rural agrarian).

PubMed

Ochieng, Beverly; Akunja, Edith; Edwards, Nancy; Mombo, Diana; Marende, Leah; Kaseje, Dan C O

2014-01-01

The shortage of health professionals in low income countries is recognized as a crisis. Community health workers are part of a "task-shift" strategy to address this crisis. Task shifting in this paper refers to the delegation of tasks from health professionals to lay, trained volunteers. In Kenya, there is a debate as to whether these volunteers should be compensated, and what motivation strategies would be effective in different socio-demographic contexts, based type of tasks shifted. The purpose of this study was to find out, from stakeholders' perspectives, the type of tasks to be shifted to community health workers and the appropriate strategies to motivate and retain them. This was an analytical comparative study employing qualitative methods: key informant interviews with health policy makers, managers, and service providers, and focus group discussions with community health workers and service consumers, to explore their perspectives on tasks to be shifted and appropriate motivation strategies. The study found that there were tasks to be shifted and motivation strategies that were common to all three contexts. Common tasks were promotive, preventive, and simple curative services. Common motivation strategies were supportive supervision, means of identification, equitable allocation of resources, training, compensation, recognition, and evidence based community dialogue. The study concluded that inclusion of curative tasks for community health workers, particularly in nomadic contexts, is inevitable but raises the need for accreditation of their training and regulation of their tasks.

Hydration Status, Kidney Function, and Kidney Injury in Florida Agricultural Workers.

PubMed

Mix, Jacqueline; Elon, Lisa; Vi Thien Mac, Valerie; Flocks, Joan; Economos, Eugenia; Tovar-Aguilar, Antonio J; Stover Hertzberg, Vicki; McCauley, Linda A

2018-05-01

Recent findings suggest that laboring in hot occupational environments is related to kidney damage in agricultural workers. We examined hydration status and kidney function in 192 Florida agricultural workers. Blood and urine samples were collected over 555 workdays during the summers of 2015 and 2016. Urine-specific gravity (USG), serum creatinine, and other kidney function markers were examined pre- and post-shift on each workday. Multivariable mixed modeling was used to examine the association of risk factors with hydration status and acute kidney injury (AKI). Approximately 53% of workers were dehydrated (USG ≥1.020) pre-shift and 81% post-shift; 33% of participants had AKI on at least one workday. The odds of AKI increased 47% for each 5-degree (°F) increase in heat index. A strikingly high prevalence of dehydration and AKI exists in Florida agricultural workers.

Combined effects of noise and shift work on fatigue as a function of age.

PubMed

Saremi, Mahnaz; Rohmer, Odile; Burgmeier, André; Bonnefond, Anne; Muzet, Alain; Tassi, Patricia

2008-01-01

The study was conducted to analyse possible interactions between noise and shift work, and fatigue as a function of age. In a large questionnaire survey, we assessed personal and environmental risk factors related to fatigue. Noise exposure at work (L(Aeq, 8hr)) was measured with personal noise dosimetry. The sample included 254 day and shift workers, and was divided into 2 age groups (<40- and >40-year-olds). Noise exposure had a main effect on fatigue. The highest noise exposure resulted in an increase in the fatigue level of older shift workers. The quantity of sleep mainly depended on the type of shift and age. Our data suggest that the most important factor generating fatigue could be related to industrial noise exposure, a factor which seems to aggravate work-related fatigue generated in a synergic manner by shift work and ageing. Senior workers should be prevented from cumulating those occupational stressors.

Increasing off-service resident productivity while on their emergency department rotation using shift cards.

PubMed

Chakravarthy, Bharath; Posadas, Emerson; Ibrahim, Deena; McArthur, Kurt; Osborn, Megan; Hoonpongsimanont, Wirachin; Wong, Andrew; Lotfipour, Shahram

2015-04-01

Differences in productivity between off-service residents rotating in the emergency department (ED) and their emergency medicine (EM) resident counterparts have never been directly quantified. We sought to quantify the difference between off-service residents rotating in the ED and their EM resident counterparts. We also sought to find whether shift cards could be used to increase the productivity of off-service residents rotating in the ED. This is a prospective cohort study conducted at an urban, tertiary, Level I trauma center. We implemented the use of shift cards for off-service residents during their EM rotation. Completion of the shift card involved recording patients seen and their dispositions, procedures done, and documenting a learned bedside teaching point from their shift that day. Productivity was measured in terms of patients seen per hour (PPH) and relative value units per hour (RVU/h). Off-service residents showed a productivity of 0.529 PPH (95% confidence interval [CI] 0.493-0.566) and 1.40 RVU/h (95% CI 1.28-1.53) prior to implementation of shift cards. With the introduction of shift cards, productivity increased to 0.623 PPH (95% CI 0.584-0.663, p = 0.001) and 1.77 RVU/h (95% CI 1.64-1.91, p = 0.001). In comparison, first year EM resident productivity was 0.970 PPH (95% CI 0.918-1.02) and 3.01 RVU/h (95% CI 2.83-3.19). Shift cards can be used to foster motivation for off-service residents rotating in the ED, and is a simple and cost-effective method to improve system-based practices and utilization of resources. Copyright © 2015 Elsevier Inc. All rights reserved.

The effects of shift work on sleeping quality, hypertension and diabetes in retired workers.

PubMed

Guo, Yanjun; Liu, Yuewei; Huang, Xiji; Rong, Yi; He, Meian; Wang, Youjie; Yuan, Jing; Wu, Tangchun; Chen, Weihong

2013-01-01

Shift work has been associated with adverse health effects by disturbing circadian rhythms. However,its potential long-term health effects and the persistent effects after leaving shifts have not been well established. We studied 26,463 workers from Tongji-Dongfeng Cohort in China. All the participants are retired employees of Dongfeng Motor Company. Information on demographics, occupational history and medical history were gathered through questionnaires. After adjusting potential confounders in the logistic regression models, shift work was associated with poor sleeping quality, diabetes and hypertension independently. We observed significant effects of shift work on poor sleeping quality, diabetes and hypertension; the ORs (95%CI) are 1.18 (1.09-1.27), 1.10 (1.03-1.17) and 1.05 (1.01-1.09) respectively. In the further analysis, we found elevated ORs (95%CI) for participants with poor sleeping quality, the ORs (95%CI) are 1.34 (1.08-1.60), 1.13 (1.05-1.21), 1.05 (1.03-1.07) and 1.05 (1.01-1.09) for 1-4, 5-9, 10-19, ≥20 years of shift work respectively. However, with the extension of leaving shift work duration, the effects of shift work on sleep quality gradually reduced. Shift work may be an independent risk factor for sleeping quality, diabetes and hypertension even in retired workers. Applicable intervention strategies are needed for prevention of sleep loss, diabetes, and hypertension for shift workers.

Sleep and need for recovery in shift workers: do chronotype and age matter?

PubMed

van de Ven, Hardy A; van der Klink, Jac J L; Vetter, Céline; Roenneberg, Till; Gordijn, Marijke; Koolhaas, Wendy; de Looze, Michiel P; Brouwer, Sandra; Bültmann, Ute

2016-01-01

This study examined associations of chronotype and age with shift-specific assessments of main sleep duration, sleep quality and need for recovery in a cross-sectional study among N = 261 industrial shift workers (96.6% male). Logistic regression analyses were used, adjusted for gender, lifestyle, health, nap behaviour, season of assessment and shift schedule. Shift workers with latest versus earliest chronotype reported a shorter sleep duration (OR 11.68, 95% CI 3.31-41.17) and more awakenings complaints (OR 4.84, 95% CI 4.45-11.92) during morning shift periods. No associations were found between chronotype, sleep and need for recovery during evening and night shift periods. For age, no associations were found with any of the shift-specific outcome measures. The results stress the importance of including the concept of chronotype in shift work research and scheduling beyond the concept of age. Longitudinal research using shift-specific assessments of sleep and need for recovery are needed to confirm these results. Chronotype seems to better explain individual differences in sleep than age. In view of ageing societies, it might therefore be worthwhile to further examine the application of chronotype for individualised shift work schedules to facilitate healthy and sustainable employment.

Investigating the factorial structure and availability of work time control in a representative sample of the Swedish working population.

PubMed

Albrecht, Sophie C; Kecklund, Göran; Tucker, Philip; Leineweber, Constanze

2016-05-01

Past research has often neglected the sub-dimensions of work time control (WTC). Moreover, differences in levels of WTC with respect to work and demographic characteristics have not yet been examined in a representative sample. We investigated these matters in a recent sample of the Swedish working population. The study was based on the 2014 data collection of the Swedish Longitudinal Occupational Survey of Health. We assessed the structure of the WTC measure using exploratory and confirmatory factor analysis. Differences in WTC by work and demographic characteristics were examined with independent samplet-tests, one-way ANOVAs and gender-stratified logistic regressions. Best model fit was found for a two-factor structure that distinguished between control over daily hours and control over time off (root mean square error of approximation = 0.06; 95% CI 0.04 to 0.09; Comparative Fit Index (CFI) = 0.99). Women, shift and public-sector workers reported lower control in relation to both factors. Age showed small associations with WTC, while a stronger link was suggested for civil status and family situation. Night, roster and rotating shift work seemed to be the most influential factors on reporting low control over daily hours and time off. Our data confirm the two-dimensional structure underlying WTC, namely the components 'control over daily hours' and 'control over time off'. Women, public-sector and shift workers reported lower levels of control. Future research should examine the public health implications of WTC, in particular whether increased control over daily hours and time off can reduce health problems associated with difficult working-time arrangements. © 2015 the Nordic Societies of Public Health.

Concepts in human biological rhythms

PubMed Central

Reinberg, Alain; Ashkenazi, Israel

2003-01-01

Biological rhythms and their temporal organization are adaptive phenomena to periodic changes in environmental factors linked to the earth's rotation on its axis and around the sun. Experimental data from the plant and animal kingdoms have led to many models and concepts related to biological clocks that help describe and understand the mechanisms of these changes. Many of the prevailing concepts apply to all organisms, but most of the experimental data are insufficient to explain the dynamics of human biological clocks. This review presents phenomena thai are mainly characteristic ofand unique to - human chronobiology, and which cannot be fully explained by concepts and models drawn from laboratory experiments. We deal with the functional advantages of the human temporal organization and the problem of desynchronization, with special reference to the period (τ) of the circadian rhythm and its interindividual and intraindividual variability. We describe the differences between right- and left-hand rhythms suggesting the existence of different biological clocks in the right and left cortices, Desynchronization of rhythms is rather frequent (one example is night shift workers). In some individuals, desynchronization causes no clinical symptoms and we propose the concept of “allochronism” to designate a variant of the human temporal organization with no pathological implications. We restrict the term “dyschronism” to changes or alterations in temporal organization associated with a set of symptoms similar to those observed in subjects intolerant to shift work, eg, persisting fatigue and mood and sleep alterations. Many diseases involve chronic deprivation of sleep at night and constitute conditions mimicking thai of night shift workers who are intolerant to desynchronization. We also present a genetic model (the dian-circadian model) to explain interindividual differences in the period of biological rhythms in certain conditions. PMID:22033796

Investigating the factorial structure and availability of work time control in a representative sample of the Swedish working population

PubMed Central

Albrecht, Sophie C.; Kecklund, Göran; Tucker, Philip; Leineweber, Constanze

2015-01-01

Aims: Past research has often neglected the sub-dimensions of work time control (WTC). Moreover, differences in levels of WTC with respect to work and demographic characteristics have not yet been examined in a representative sample. We investigated these matters in a recent sample of the Swedish working population. Methods: The study was based on the 2014 data collection of the Swedish Longitudinal Occupational Survey of Health. We assessed the structure of the WTC measure using exploratory and confirmatory factor analysis. Differences in WTC by work and demographic characteristics were examined with independent sample t-tests, one-way ANOVAs and gender-stratified logistic regressions. Results: Best model fit was found for a two-factor structure that distinguished between control over daily hours and control over time off (root mean square error of approximation = 0.06; 95% CI 0.04 to 0.09; Comparative Fit Index (CFI) = 0.99). Women, shift and public-sector workers reported lower control in relation to both factors. Age showed small associations with WTC, while a stronger link was suggested for civil status and family situation. Night, roster and rotating shift work seemed to be the most influential factors on reporting low control over daily hours and time off. Conclusions: Our data confirm the two-dimensional structure underlying WTC, namely the components ‘control over daily hours’ and ‘control over time off’. Women, public-sector and shift workers reported lower levels of control. Future research should examine the public health implications of WTC, in particular whether increased control over daily hours and time off can reduce health problems associated with difficult working-time arrangements. PMID:26620363

Rapid counterclockwise shift rotation in air traffic control: effects on sleep and night work.

PubMed

Signal, T Leigh; Gander, Philippa H

2007-09-01

In Air Traffic Control, counterclockwise rapidly rotating shift schedules are often employed but may result in significant sleep loss. This has potential consequences for performance, particularly if a night shift is worked. As part of a large-scale field study, the pattern of sleep across a 4-d counterclockwise, rapidly rotating schedule (afternoon, day, morning, night shift) was documented and relationships between prior sleep and performance during the night shift were investigated. There were 28 controllers who completed 4 periods of data collection which included 2 d before and 2 d after a 4-d shift cycle. Sleep was recorded using an actigraph and sleep diary, and performance on each night shift was measured three times using the Psychomotor Vigilance Task. Across the work week, sleep duration decreased largely due to earlier rise times associated with shift start times moving backward. In the short turn-around between the morning and night shift, 90% of controllers slept for an average of 2.2 h. Improved performance on the night shift was related only to longer periods of sleep the night prior. This study demonstrates that a 4-d counterclockwise, rapidly rotating schedule results in a progressive reduction in sleep and consequently the rapid accumulation of a sleep debt. To help maintain their performance on the night shift, it is recommended that controllers attempt to obtain at least 6 h sleep the night before a night shift. It is also recommended that ATC providers educate their workforce about this issue.

Work schedule and self-reported hypertension - the potential beneficial role of on-shift naps for night workers.

PubMed

Rotenberg, Lúcia; Silva-Costa, Aline; Vasconcellos-Silva, Paulo Roberto; Griep, Rosane Härter

2016-01-01

Data on the association between shift work and hypertension are controversial. Sleep restriction is hypothesized to be involved in this relationship. Since on-shift nap can partly compensate for sleep deprivation among night workers, this investigation is aimed at (i) comparing the prevalence of hypertension among workers considering both current and former night work, (ii) testing the association between on-shift naps and hypertension among night workers, and (iii) analyzing the influence of sleep complaints in the association between on-shift nap and hypertension. Nap was defined as a sleep episode with duration shorter than the average nighttime sleep. A cross-sectional study was performed at the 18 largest public hospitals in Rio de Janeiro, Brazil, in 2010-2011 (N = 2588 female registered nurses). Nurses were informally allowed to nap for up to three consecutive hours during working nights. Workers completed a multidimensional questionnaire including self-reported information on physician diagnosis of hypertension, napping, and sleep complaints (insomnia, diurnal sleepiness, and non-satisfactory sleep). Epidemiological and statistical treatment of data included binomial logistic regression and interaction tests. Higher chances of hypertension were observed for both current and former night workers compared with workers with no previous experience in night work, i.e. exclusive day workers (OR = 1.68; CI95% 1.22-2.33 and OR = 1.40; CI95% 1.01-1.96, respectively) after adjustment for age, race/ethnicity, physical activity, smoking, alcohol consumption, insomnia, weekly work hours, and BMI. Compared with exclusive day workers, both non-nappers and nappers were at a higher likelihood of reporting hypertension (OR = 1.93 CI95% 1.35-2.79 and OR = 1.41 CI95% 1.08-2.20, respectively). An interaction was observed between napping behavior and insomnia (p = 0.037). In the whole sample of night workers, the lower OR for nappers was confirmed when they were directly compared with non-nappers (OR = 0.76 CI95% 0.59-0.98). Analysis of night workers stratified by insomnia showed a significant reduction in OR for nappers (compared to non-nappers) only among insomniacs (OR = 0.58). Napping during night work may be a protective factor for hypertension, particularly among insomniacs. Factors related to melatonin secretion, blood pressure control, and blood pressure dipping patterns are likely to be involved in the relationship between on-shift napping and blood pressure.

Prospective evaluation of postoperative compliance and outcomes after rotator cuff repair in patients with and without workers' compensation claims.

PubMed

Cuff, Derek J; Pupello, Derek R

2012-12-01

This study prospectively evaluated compliance and outcomes after rotator cuff repair in patients with and without Workers' Compensation claims. From December 2007 to January 2010, 42 consecutive patients with Workers' Compensation claims (Work Comp group), and 50 consecutive patients without a Workers' Compensation claim (non-Work Comp group) underwent arthroscopic rotator cuff repair and were enrolled in this study. Compliance with a postoperative protocol of shoulder immobilization and physical therapy was documented. Patients were monitored clinically for a minimum of 12 months. Noncompliance with protocol was documented in 22 of 42 patients (52%) in the Work Comp group compared with 2 of 50 (4%) in the non-Work Comp group (P < .001). The Work Comp group had less improvement in preoperative to postoperative outcome scores for the American Shoulder and Elbow Surgeons (ASES) score (40.4 to 60.1), Simple Shoulder Test (SST) score (3.9 to 6.0) and visual analog scale (VAS) for pain (7.0 to 3.5) compared with the non-Work Comp group (ASES, 41.7 to 89.2; SST, 4.3 to 10.7; VAS, 6.2 to 0.35; P < .0001). The compliant Work Comp patients had more favorable results in final outcome scores (ASES, 73.1; SST, 7.9; VAS, 1.5) than noncompliant Work Comp patients (ASES, 48.4; SST, 4.3; VAS, 5.3; P < .0001). Patients with Workers' Compensation claims demonstrated a high rate of postoperative noncompliance (52%) compared with patients without Workers' Compensation claims (4%) after rotator cuff repair. Those Workers' Compensation patients who had no evidence of noncompliance had significant improvements and more favorable outcomes than the noncompliant Workers' Compensation patients. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Neuroendocrine recovery after 2-week 12-h day and night shifts: an 11-day follow-up.

PubMed

Merkus, Suzanne L; Holte, Kari Anne; Huysmans, Maaike A; Hansen, Åse Marie; van de Ven, Peter M; van Mechelen, Willem; van der Beek, Allard J

2015-02-01

The study aimed to investigate the course and duration of neuroendocrine recovery after 2-week 12-h day and night shift working periods and to study whether there were differences in recovery between the shift groups. Twenty-nine male offshore employees working 2-week 12-h shift tours participated in the study; 15 participated after a day shift tour and 14 after a night shift tour. Salivary cortisol was assessed at awakening, 30 min after awakening, and before bedtime on the 1st, 4th, 7th, and 11th day of the free period, with a reference day prior to the offshore tour. Differences were tested using generalised estimating equations analysis. Compared to the reference day, night shift workers had a significantly flatter cortisol profile on the 1st day off, significantly lower cortisol concentrations at 30 min after awakening on day 4 and at awakening on day 7, and a significantly smaller decline to evening concentration on days 4 and 11. Compared to the reference day, day shift workers only showed a significantly lower cortisol concentration at awakening on the 1st day off. Compared to day workers, night shift workers had a flatter profile on the 1st day off and a lower cortisol concentration at awakening on the 4th day. Following 2-week 12-h night shift working periods, recovery was not fully complete up to day 11. Following 2-week 12-h day shift working periods, an indication of incomplete recovery was found on the 1st day off, with full recovery reached on day 4.

The correlation between movement of the center of mass and the kinematics of the spine, pelvis, and hip joints during body rotation.

PubMed

Wada, Osamu; Tateuchi, Hiroshige; Ichihashi, Noriaki

2014-01-01

Body rotation is associated with many activities. The concomitant movement of the center of mass (COM) is essential for effective body rotation. This movement is considered to be influenced by kinematic changes in the spine, pelvis, and hip joints. However, there is no research on the association between COM movement and kinematic changes during body rotation. We aimed to investigate the association between COM movement and the kinematics of the spine, pelvis, and hip joints during body rotation in standing. Twenty-four healthy men were included in the study. COM movement during active body rotation in a standing position was measured. We evaluated pelvic shift and changes in the angles of the spine, pelvis, and hip joints. We calculated the Pearson correlation coefficients to analyze the relationship between COM movement and kinematic changes in the spine, pelvis, and hip joints. There were significant correlations between lateral COM movement to the rotational side and pelvic shift to the rotational side, and between posterior COM movement and pelvic shift to the posterior side. In addition, lateral COM movement to the rotational side showed significant and negative correlation with spinal flexion and was significantly and positively correlated with the change in anterior pelvic tilt. Clinicians need to take particular note of both spinal and pelvic motion in the sagittal plane, as well as the pelvic shift, to speculate COM movement during body rotation in standing. Copyright © 2013 Elsevier B.V. All rights reserved.

Sleep problems and workplace injuries in Canada.

PubMed

Kling, Rakel N; McLeod, Christopher B; Koehoorn, Mieke

2010-05-01

To investigate the association between sleep problems and risk of work injuries among Canadian workers and to identify working groups most at risk for injuries. Population-based cross-sectional survey. Canada Participants: Working-age respondents (15-64 years of age) who worked part or full-time in the last 12 months (n = 69,584). None. This study used data from the Canadian Community Health Survey (CCHS) Cycle 1.1 2000-2001. The main indicator of sleep problems was reporting trouble going to sleep or staying asleep. Stratified logistic regression models were used to calculate odds ratios (OR) and 95% confidence intervals (CI) for the association of sleep problems and work injury after adjusting for potential confounders and for the survey design. Trouble sleeping most of the time was significantly associated with work injury in both men (OR = 1.25, 95% CI = 1.01-1.55) and women (OR = 1.54, 95% CI = 1.25-1.91). The multivariate stratified analysis found that men in trades and transportation jobs (OR = 1.50, 95% CI = 1.09-2.08), women in processing and manufacturing jobs (OR = 2.46, 95% CI = 1.11-5.47), and women who work rotating shifts (OR = 1.71, 95% CI = 1.11-2.64) were at the highest increased risk for work injury associated with trouble sleeping. Trouble sleeping was associated with an increased risk of work injury. The number of injuries attributable to sleep problems was higher for women compared to men. While most job classes and shift types showed an increased risk of injury, some groups such as women in processing and manufacturing and those who work rotating shifts warrant further investigation and attention for intervention.

Cortisol, reaction time test and health among offshore shift workers.

PubMed

Harris, Anette; Waage, Siri; Ursin, Holger; Hansen, Ase Marie; Bjorvatn, Bjørn; Eriksen, Hege R

2010-10-01

The stress hormone cortisol shows a pronounced endogenous diurnal rhythm, which is affected by the sleep/wake cycle, meals and activity. Shift work and especially night work disrupts the sleep/wake cycle and causes a desynchronization of the natural biological rhythms. Therefore, different shift schedules may have different impact on performance at work and health. The purpose was to study if health, reaction time, and the cortisol rhythm were negatively affected when a group of shift workers changed their work schedule from ordinary day-night shift (fixed shift) to "swing shift". 19 healthy workers on a Norwegian oil rig participated in the study. They worked 2 weeks offshore followed by 4 weeks off work. The ordinary schedule consisted of 12-h day shift and 12-h night shift every other work period (14 days or nights=fixed shift). "Swing shift" involved 1 week of night shift, followed by 1 week of day shift during the work period. All participants worked ordinary day-night shift when baseline data were collected (questionnaires, saliva cortisol, and reaction time during work). After collection of baseline data the workers changed their work schedule to "swing shift", for every working period, and 9 months later the same data were collected. "Swing shift" did not give any negative health effects or any negative changes in reaction time during the day they shifted from night work to day work. Personnel adapted to night shift within a week regardless of schedule, but recovery from night shift took longer time. During swing shift the cortisol rhythm went back towards a normal rhythm in the second week, but it was not returned completely to normal values when they returned home for the 4 weeks off period. However, the cortisol rhythms were readapted to normal values after 1 week at home. For personnel returning home directly from 14 consecutive night shifts, cortisol adaptation was not complete after 1 week at home. We found no increase in health complaints from swing shift or reaction time in the shift from night to day work. Recovery from night shift takes longer time. Copyright © 2010 Elsevier Ltd. All rights reserved.

Oxidative stress and insulin resistance in policemen working shifts.

PubMed

Demir, Irfan; Toker, Aysun; Zengin, Selcuk; Laloglu, Esra; Aksoy, Hulya

2016-04-01

Shift work is a work schedule involving irregular or unusual hours, compared to those of a normal daytime work schedule. In developed countries, night shift work is very common. In several cities of our country, 12/24 shift system is implemented in police organization. While night shift work composes half of the 20 shift in a month, in ergonomic shift system, an alternative shift schedule, shift work can be performed in three shifts in a day. In this study, we aimed to investigate the effects of 12/24 shift work system on insulin resistance and oxidative stress and systemic inflammation. Two hundred and four 12/24 shift workers (age 44.3 ± 5.6 years) and 193 ergonomic shift workers (age 42.6 ± 5.5 years) were included to study. Serum oxidized LDL (ox-LDL), neutrophil gelatinase lipocalin-2 (NGAL) as oxidative stress markers, glucose, insulin, ferritin, high-sensitive C-reactive protein (hsCRP) and erythrocyte sedimentation rate values were measured. Homeostasis model assessment for insulin resistance (HOMA-IR) was calculated to evaluate insulin resistance. Serum ox-LDL, HOMA-IR, hsCRP and NGAL levels in 12/24 shift system were found to be significantly higher compared with ergonomic shift workers (p < 0.0001, p = 0.02, p = 0.03, p = 0.02, respectively). When evaluated all subjects, weak but significant correlation was found between HOMA-IR with ox-LDL (r = 0.12, p = 0.01), hsCRP (r = 0.17, p = 0.001) and ferritin (r = 0.15, r = 0.003). Also in 12/24 shift work group, there were significant correlations between HOMA-IR with hsCRP (r = 0.17, p = 0.01) and ferritin (r = 0.25, p = 0.0001). It may be concluded that 12/24 shift system might give rise to insulin resistance and oxidative stress. Additionally, workers in this system may under risk of systemic inflammatory response. Working hours must be arranged in accordance with the physiological rhythm.

Meals, snacks and food choices in Brazilian shift workers with high energy expenditure.

PubMed

de Assis, M A A; Nahas, M V; Bellisle, F; Kupek, E

2003-08-01

To describe the food intake of garbage collectors, who works in three shifts, in terms of meal and snack frequency, content, time distribution and the contribution of various popular foods to the total diet. Sixty-six Brazilian garbage collectors, who work in morning, afternoon, and night shift, participated in the present study. The quantitative methods used were a combination of one 24-h recall and two 24-h records during three nonconsecutive work days. The qualitative method used was the food-based classification of eating episodes model modified in order to define meals or snacks in three categories of events: meals with three food groups of high nutrient density (three HND meals), meals with two food groups of high nutrient density (two HND meals) and snacks, composed of only one food category of high nutrient density. The total number of eating events per day was significantly higher for night shift workers. Over 24-h, 'two HND meals' were the most common events and contributed the most energy, in all three shifts. Night shift workers ate more at dawn and less in the morning than other shifts. In all three shifts, meat was the most important food contributing to energy intake. Different work schedules did not affect the relative frequency of meal types and snacks or their contribution to daily energy intake, but affected the daily distribution of eating events, with a redistribution of intake from day to night in night shift workers.

Carpal Tunnel Syndrome

MedlinePlus

... worker's wrist to maintain a natural position during work. Jobs can be rotated among workers. Employers can develop programs in ergonomics, the process of adapting workplace conditions and job ...

Ocular Measures of Sleepiness Are Increased in Night Shift Workers Undergoing a Simulated Night Shift Near the Peak Time of the 6-Sulfatoxymelatonin Rhythm

PubMed Central

Ftouni, Suzanne; Sletten, Tracey L.; Nicholas, Christian L.; Kennaway, David J.; Lockley, Steven W.; Rajaratnam, Shantha M.W.

2015-01-01

Study Objectives: The study examined the relationship between the circadian rhythm of 6-sulphatoxymelatonin (aMT6s) and ocular measures of sleepiness and neurobehavioral performance in shift workers undergoing a simulated night shift. Methods: Twenty-two shift workers (mean age 33.4, SD 11.8 years) were tested at approximately the beginning (20:00) and the end (05:55) of a simulated night shift in the laboratory. At the time point corresponding to the end of the simulated shift, 14 participants were classified as being within range of 6-sulphatoxymelatonin (aMT6s) acrophase— defined as 3 hours before or after aMT6s peak—and 8 were classified as outside aMT6s acrophase range. Participants completed the Karolinska Sleepiness Scale (KSS) and the auditory psychomotor vigilance task (aPVT). Waking electroencephalography (EEG) was recorded and infrared reflectance oculography was used to collect ocular measures of sleepiness: positive and negative amplitude/velocity ratio (PosAVR, NegAVR), mean blink total duration (BTD), the percentage of eye closure (%TEC), and a composite score of sleepiness levels (Johns Drowsiness Scale; JDS). Results: Participants who were tested within aMT6s acrophase range displayed higher levels of sleepiness on ocular measures (%TEC, BTD, PosAVR, JDS), objective sleepiness (EEG delta power frequency band), subjective ratings of sleepiness, and neurobehavioral performance, compared to those who were outside aMT6s acrophase range. Conclusions: The study demonstrated that objective ocular measures of sleepiness are sensitive to circadian rhythm misalignment in shift workers. Citation: Ftouni S, Sletten TL, Nicholas CL, Kennaway DJ, Lockley SW, Rajaratnam SM. Ocular measures of sleepiness are increased in night shift workers undergoing a simulated night shift near the peak time of the 6-sulfatoxymelatonin rhythm. J Clin Sleep Med 2015;11(10):1131–1141. PMID:26094925

Occupational health services for shift and night workers.

PubMed

Koller, M

1996-02-01

It is important for an occupational health service to plan health supervision and measures for shift and night workers considering the biorhythmic and psychosocial desynchronisation, as well as the frequent prevalence of combined effects of adverse environmental and working conditions. The measures taken should be preventive to reduce the expected health risks rather than being rehabilitative. Both a medical surveillance and a counselling service are recommended before and during engagement in shift and night work. Sleep, digestive, metabolic and cardiovascular troubles should be noted and followed up. Medical counselling is especially necessary in the first months of shift and night work exposure and then after long-term exposure. The postulate for timed surveillance and intervention is supported by data of our epidemiologic investigations. The importance of the single health measures is underlined by direct reference to the relevant literature. Recommendations that should be applied in all countries and enterprises are in accordance with the ILO Night Work Convention 1990a and include: (1) appropriate occupational health services provided for night and shift workers, including counselling; (2) first aid facilities during all shift hours; (3) the option of transfer to day work when certified unfit for night work for reasons of health; and (4) measures for women on night shifts, in particular special maternity protection (transfer to day work, social security benefits or an extension of maternity leave). Examples of occupational health services already installed in some states for shift and night workers, and information on future developments are given. Up to now the medical service has been implemented mostly on the basis of collective agreements rather than on the basis of legal provisions. The Austrian Night Shift/Heavy Work Law Regulations of 1981, revised 1993, are cited: workers exposed to night shifts under defined single or combined additional heavy workloads are entitled to a special health assessment, additional rest pauses, additional free time and early retirement depending on years of exposure.

Effects of long working hours and the night shift on severe sleepiness among workers with 12-hour shift systems for 5 to 7 consecutive days in the automobile factories of Korea.

PubMed

Son, Mia; Kong, Jeong-Ok; Koh, Sang-Baek; Kim, Jaeyoung; Härmä, Mikko

2008-12-01

We investigated the effects of 12-hour shift work for five to seven consecutive days and overtime on the prevalence of severe sleepiness in the automobile industry in Korea. [Correction added after online publication 28 Nov: Opening sentence of the summary has been rephrased for better clarity.] A total of 288 randomly selected male workers from two automobile factories were selected and investigated using questionnaires and sleep-wake diaries in South Korea. The prevalence of severe sleepiness at work [i.e. Karolinska Sleepiness Scale (KSS) score of 7 or higher] was modeled using marginal logistic regression and included theoretical risk factors related to working hours and potential confounding factors related to socio-economic status, work demands, and health behaviors. Factors related to working hours increased the risk for severe sleepiness at the end of the shift in the following order: the night shift [odds ratio (OR): 4.7; 95% confidence interval (CI): 3.6-6.0)], daily overtime (OR: 2.2; 95% CI: 1.7-2.9), weekly overtime (OR: 1.6; 95% CI: 1.0-2.6), and night overtime (OR: 1.6; 95% CI: 0.8-3.0). Long working hours and shift work had a significant interactive effect for severe sleepiness at work. Night shift workers who worked for 12 h or more a day were exposed to a risk of severe sleepiness that was 7.5 times greater than day shift workers who worked less than 11 h. Night shifts and long working hours were the main risk factors for severe sleepiness among automobile factory workers in Korea. Night shifts and long working hours have a high degree of interactive effects resulting in severe sleepiness at work, which highlight the need for immediate measures to address these characteristics among South Korean labor force patterns.

Adaptation to shift work: physiologically based modeling of the effects of lighting and shifts' start time.

PubMed

Postnova, Svetlana; Robinson, Peter A; Postnov, Dmitry D

2013-01-01

Shift work has become an integral part of our life with almost 20% of the population being involved in different shift schedules in developed countries. However, the atypical work times, especially the night shifts, are associated with reduced quality and quantity of sleep that leads to increase of sleepiness often culminating in accidents. It has been demonstrated that shift workers' sleepiness can be improved by a proper scheduling of light exposure and optimizing shifts timing. Here, an integrated physiologically-based model of sleep-wake cycles is used to predict adaptation to shift work in different light conditions and for different shift start times for a schedule of four consecutive days of work. The integrated model combines a model of the ascending arousal system in the brain that controls the sleep-wake switch and a human circadian pacemaker model. To validate the application of the integrated model and demonstrate its utility, its dynamics are adjusted to achieve a fit to published experimental results showing adaptation of night shift workers (n = 8) in conditions of either bright or regular lighting. Further, the model is used to predict the shift workers' adaptation to the same shift schedule, but for conditions not considered in the experiment. The model demonstrates that the intensity of shift light can be reduced fourfold from that used in the experiment and still produce good adaptation to night work. The model predicts that sleepiness of the workers during night shifts on a protocol with either bright or regular lighting can be significantly improved by starting the shift earlier in the night, e.g.; at 21:00 instead of 00:00. Finally, the study predicts that people of the same chronotype, i.e. with identical sleep times in normal conditions, can have drastically different responses to shift work depending on their intrinsic circadian and homeostatic parameters.

Variations of cortisol, fatigue and sleep disturbances in sound engineers: effect of job task and fast backward-rotating shifts.

PubMed

Vangelova, Katia K

2008-01-01

The aim was to study the effect of job task and fast backward-rotating shifts on the time-of-day variations of cortisol, fatigue, and sleep disturbances in broadcasting sound engineers. The concentration of saliva cortisol and ratings of stress, sleepiness, and fatigue were followed at 3-hour intervals during the fast backward-rotating shifts in 26 sound engineers: 14 subjects from control rooms, aged 45.1 +/- 7.3 years, and 12 subjects working in direct transmissions, aged 51.7 +/- 6.0 years. Saliva cortisol was assessed using an radioimmunology kit. The participants reported for stress symptoms after the shifts and filled a sleep diary. The effects of job task, shift, and time-of-day were analyzed by tests of between-subjects effects (SPSS). Cortisol retained the typical diurnal pattern with a highly significant effect of the shift. The job task and the shift interacted significantly. Higher cortisol values during the morning and night shifts in engineers working in direct transmissions were found. Their stress ratings were also higher, as well as the ratings of sleepiness and fatigue. The quality of sleep was worse in engineers working in direct transmissions. In conclusion, our data indicate that stress and fast backward-rotating shifts in sound engineers working in direct transmissions affect physiological stress markers such as cortisol and increase sleepiness, fatigue, and sleep problems.

Self-reported health and sleep complaints among nursing personnel working under 12 h night and day shifts.

PubMed

Portela, Luciana F; Rotenberg, Lúcia; Waissmann, William

2004-01-01

This cross-sectional exploratory study involved health care workers of various skill types and levels. We tested the hypothesis that the prevalence of diseases, sleep complaints, and insufficient time for nonprofessional activities (family, leisure, and rest) are higher among night than day workers. Data collection was carried out in two public hospitals using questionnaires and other forms. Night work was explored as a risk factor, considering a night worker as one who had at least one night job on the occasion of the research. Data were assessed by a univariate analysis. The association between work schedule and the dependent variables--health conditions, sleep complaints, and insufficient time for nonprofessional activities--was evaluated through the estimation of the prevalence ratio, with a confidence interval of 95%. Two hundred and fifty-eight female nursing personnel participated; 41.5% were moonlighters, and only 20 worked a shift of less than 12h in length. Reports of migraine and need of medical care the 2 weeks before the survey were more prevalent among day than night workers (PR=0.71; CI=0.55-0.92 and PR=0.71; CI=0.52-0.95, respectively). Migraine headaches occurred less frequently among night than day workers as confirmed by comparing the reports of the night workers and day workers whose work history was always day shifts (PR = 0.74; CI = 0.57-0.96). Reports of mild emotional disorders (mild depression, tension, anxiety, or insomnia) were less frequent among night (PR=0.76; CI=0.59-0.98) and ex-night workers (PR=0.68; CI=0.50-0.91) than day workers who never had worked a night job. The healthy worker effect does not seem to explain the results of the comparisons between day and night workers. The possible role of exposure by day workers to some risk factors, such as stress, was suggested as an explanation for these results. No significant difference was observed between night and day workers as to sleep complaints, a result that may have been influenced by the nature of the shift-work schedule (no successive night shifts) and possibly nap taking during the night shift. Moreover, the long work hours and moonlighting of the healthcare workers, which is common in Brazil, may have masked other possible differences between the day and night workers. Among night workers, a significant relation was found between years working nights (more than 10 yrs) and high cholesterol values (PR = 2.58; CI = 1.07-6.27), a result that deserves additional study. Working nights more than four times per 2-week span was related to complaints about insufficient time for children (PR= 1.96; CI = 1.38-2.78) and rest/leisure (PR= 1.54; CI = 1.20-1.99). These results can be related to the "social value of time," as evenings and nights are when families usually spend time together. The complexity of the professional life and the consequent heterogeneity of the group of workers under shift-work schemes confound the results. More in-depth study of the questions raised here demands a more sophisticated epidemiological treatment and larger sample size.

Whole Genome Expression in Peripheral-Blood Samples of Workers Professionally Exposed to Polycyclic Aromatic Hydrocarbons

PubMed Central

Wu, Ming-Tsang; Lee, Tzu-Chi; Su, Hung-Ju; Huang, Jie-Len; Peng, Chiung-Yu; Wang, Weihsin; Chou, Ting-Yu; Lin, Ming-Yen; Lin, Wen-Yi; Huang, Chia-Tsuan; Pan, Chih-Hong; Ho, Chi-Kung

2011-01-01

This study aims to examine global gene expression profiles before and after the work-shift among coke-oven workers (COW). COW work six consecutive days and then take two days off. Two blood and urine samples in each worker were collected before starting to work after two-days off and end-of-shift in the sixth-day work in 2009. Altered gene expressions (ratio of gene expression levels between end-of-shift and pre-shift work) were performed by Human OneArray expression system which probes ∼30,000-transcription expression profiling of human genes. Sixteen workers, all men, were enrolled in this study. Median urinary 1-hydroxypyrene (1OHP) levels (μmole/mole creatinine) in end-of-shift work were significantly higher than those in pre-shift work (2.58 vs. 0.29, p = 0.0002). Among the 20,341 genes which passed experimental quality control, 26 gene expression changes, 7 positive and 19 negative, were highly correlated with across-the-shift urinary 1OHP levels (end-of-shift – pre-shift 1OHP) (p-value < 0.001). The high and low exposure groups of across-the-shift urinary 1OHP levels dichotomized in ∼2.00 μmole/mole creatinine were able to be distinguished by these 26 genes. Some of them are known to be involved in apoptosis, chromosome stability/DNA repair, cell cycle control/tumor suppressor, cell adhesion, development/spermatogenesis, immune function, and neuronal cell function. These findings in COW will be an ideal model to study the relationship of PAHs exposure with acute changes of gene expressions. PMID:21854004

The Effects of Shift Work on Sleeping Quality, Hypertension and Diabetes in Retired Workers

PubMed Central

Guo, Yanjun; Liu, Yuewei; Huang, Xiji; Rong, Yi; He, Meian; Wang, Youjie; Yuan, Jing; Wu, Tangchun; Chen, Weihong

2013-01-01

Background Shift work has been associated with adverse health effects by disturbing circadian rhythms. However,its potential long-term health effects and the persistent effects after leaving shifts have not been well established. Methods and Results We studied 26,463 workers from Tongji-Dongfeng Cohort in China. All the participants are retired employees of Dongfeng Motor Company. Information on demographics, occupational history and medical history were gathered through questionnaires. After adjusting potential confounders in the logistic regression models, shift work was associated with poor sleeping quality, diabetes and hypertension independently. We observed significant effects of shift work on poor sleeping quality, diabetes and hypertension; the ORs (95%CI) are 1.18 (1.09–1.27), 1.10 (1.03–1.17) and 1.05 (1.01–1.09) respectively. In the further analysis, we found elevated ORs (95%CI) for participants with poor sleeping quality, the ORs (95%CI) are 1.34 (1.08–1.60), 1.13 (1.05–1.21), 1.05 (1.03–1.07) and 1.05 (1.01–1.09) for 1–4, 5–9, 10–19, ≥20 years of shift work respectively. However, with the extension of leaving shift work duration, the effects of shift work on sleep quality gradually reduced. Conclusions Shift work may be an independent risk factor for sleeping quality, diabetes and hypertension even in retired workers. Applicable intervention strategies are needed for prevention of sleep loss, diabetes, and hypertension for shift workers. PMID:23976988

Comparison of eight and 12 hour shifts: impacts on health, wellbeing, and alertness during the shift.

PubMed

Tucker, P; Barton, J; Folkard, S

1996-11-01

The generally agreed view is that there is no ideal shift system, and that most systems will have both advantages and disadvantages. As such, attention has been placed on trying to identify good and bad features of shift systems, with a view to minimising the possible ill health as a consequence of shiftwork. The present study focuses on the duration of the shift and looks at the implications for individual health, wellbeing, and alertness during the shift of extending the shift from the traditional eight hours to 12. Two groups of chemical workers, one working 12 hour shifts and the other working eight hour shifts, took part. All completed a modified version of the standard shiftwork index (SSI), a set of self reported questionnaires related to health and wellbeing. The two groups did not differ on most outcome measures, although the differences that did exist suggested advantages for the 12 hour shift workers over the eight hour shift workers; with the notable exception of rated alertness at certain times of day. The results are explained in terms of the design of the 12 hour shift system and the specific sequencing of shifts that seem to minimise the potential for the build up of fatigue. Although the current data moderately favour 12 hour shifts, a cautionary note is sounded with regard to the implications of the alertness ratings for performance and safety.

Synchrotron radiation Mössbauer spectra of a rotating absorber with implications for testing velocity and acceleration time dilation.

PubMed

Friedman, Y; Yudkin, E; Nowik, I; Felner, I; Wille, H-C; Röhlsberger, R; Haber, J; Wortmann, G; Arogeti, S; Friedman, M; Brand, Z; Levi, N; Shafir, I; Efrati, O; Frumson, T; Finkelstein, A; Chumakov, A I; Kantor, I; Rüffer, R

2015-05-01

Many Mössbauer spectroscopy (MS) experiments have used a rotating absorber in order to measure the second-order transverse Doppler (TD) shift, and to test the validity of the Einstein time dilation theory. From these experiments, one may also test the clock hypothesis (CH) and the time dilation caused by acceleration. In such experiments the absorption curves must be obtained, since it cannot be assumed that there is no broadening of the curve during the rotation. For technical reasons, it is very complicated to keep the balance of a fast rotating disk if there are moving parts on it. Thus, the Mössbauer source on a transducer should be outside the disk. Friedman and Nowik have already predicted that the X-ray beam finite size dramatically affects the MS absorption line and causes its broadening. We provide here explicit formulas to evaluate this broadening for a synchrotron Mössbauer source (SMS) beam. The broadening is linearly proportional to the rotation frequency and to the SMS beam width at the rotation axis. In addition, it is shown that the TD shift and the MS line broadening are affected by an additional factor assigned as the alignment shift which is proportional to the frequency of rotation and to the distance between the X-ray beam center and the rotation axis. This new shift helps to align the disk's axis of rotation to the X-ray beam's center. To minimize the broadening, one must focus the X-ray on the axis of the rotating disk and/or to add a slit positioned at the center, to block the rays distant from the rotation axis of the disk. Our experiment, using the (57)Fe SMS, currently available at the Nuclear Resonance beamline (ID18) at the ESRF, with a rotating stainless steel foil, confirmed our predictions. With a slit installed at the rotation axis (reducing the effective beam width from 15.6 µm to 5.4 µm), one can measure a statistically meaningful absorption spectrum up to 300 Hz, while, without a slit, such spectra could be obtained up to 100 Hz only. Thus, both the broadening and the alignment shift are very significant and must be taken into consideration in any rotating absorber experiment. Here a method is offered to measure accurately the TD shift and to test the CH.

Rotating shift work, sleep, and accidents related to sleepiness in hospital nurses

NASA Technical Reports Server (NTRS)

Gold, D. R.; Rogacz, S.; Bock, N.; Tosteson, T. D.; Baum, T. M.; Speizer, F. E.; Czeisler, C. A.

1992-01-01

A hospital-based survey on shift work, sleep, and accidents was carried out among 635 Massachusetts nurses. In comparison to nurses who worked only day/evening shifts, rotators had more sleep/wake cycle disruption and nodded off more at work. Rotators had twice the odds of nodding off while driving to or from work and twice the odds of a reported accident or error related to sleepiness. Application of circadian principles to the design of hospital work schedules may result in improved health and safety for nurses and patients.

Sleep patterns among shift-working flight controllers of the International Space Station: an observational study on the JAXA Flight Control Team.

PubMed

Mizuno, Koh; Matsumoto, Akiko; Aiba, Tatsuya; Abe, Takashi; Ohshima, Hiroshi; Takahashi, Masaya; Inoue, Yuichi

2016-09-01

Flight controllers of the International Space Station (ISS) are engaged in shift work to provide 24-h coverage to support ISS systems. The purpose of this study was to investigate the prevalence and associated factors of shift work sleep disorder (SWSD) among Japanese ISS flight controllers. A questionnaire study was conducted using the Standard Shiftwork Index to evaluate sleep-related problems and possible associated variables. Among 52 respondents out of 73 flight controllers, 30 subjects were identified as night shift workers who worked 3 or more night shifts per month. Those night shift workers who answered "almost always" to questions about experiencing insomnia or excessive sleepiness in any case of work shifts and days off were classified as having SWSD. Additionally, 7 night shift workers participated in supplemental wrist actigraphy data collection for 7 to 8 days including 3 to 4 days of consecutive night shifts. Fourteen of 30 night shift workers were classified as having SWSD. Significant group differences were observed where the SWSD group felt that night shift work was harder and reported more frequent insomniac symptoms after a night shift. However, no other variables demonstrated remarkable differences between groups. Actigraphy results characterized 5 subjects reporting better perceived adaptation as having regular daytime sleep, for 6 to 9 h in total, between consecutive night shifts. On the other hand, 2 subjects reporting perceived maladaptation revealed different sleep patterns, with longer daytime sleep and large day-to-day variation in daytime sleep between consecutive night shifts, respectively. As the tasks for flight control require high levels of alertness and cognitive function, several characteristics, namely shift-working schedule (2 to 4 consecutive night shifts), very short break time (5 to 10 min/h) during work shifts, and cooperative work with onboard astronauts during the evening/night shift, accounted for increasing workloads especially in the case of night shifts, resulting in higher or equal prevalence of SWSD to that among other shift-working populations. Further studies are required to collect more actigraphy data and examine the possibility of interventions to improve SWSD.

Accelerating recovery from jet lag: prediction from a multi-oscillator model and its experimental confirmation in model animals

NASA Astrophysics Data System (ADS)

Kori, Hiroshi; Yamaguchi, Yoshiaki; Okamura, Hitoshi

2017-04-01

The endogenous circadian clock drives oscillations that are completely synchronized with the environmental day-night rhythms with a period of approximately 24 hours. Temporal misalignment between one’s internal circadian clock and the external solar time often occurs in shift workers and long-distance travelers; such misalignments are accompanied by sleep disturbances and gastrointestinal distress. Repeated exposure to jet lag and rotating shift work increases the risk of lifestyle-related diseases, such as cardiovascular complaints and metabolic insufficiencies. However, the mechanism behind the disruption of one’s internal clock is not well understood. In this paper, we therefore present a new theoretical concept called “jet lag separatrix” to understand circadian clock disruption and slow recovery from jet lag based on the mathematical model describing the hierarchical structure of the circadian clock. To demonstrate the utility of our theoretical study, we applied it to predict that re-entrainment via a two-step jet lag in which a four-hour shift of the light-dark cycle is given in the span of two successive days requires fewer days than when given as a single eight-hour shift. We experimentally verified the feasibility of our theory in C57BL/6 strain mice, with results indicating that this pre-exposure of jet lag is indeed beneficial.

Shift Work and Sleep: Medical Implications and Management

PubMed Central

Jehan, Shazia; Zizi, Ferdinand; Pandi-Perumal, Seithikurippu R; Myers, Alyson K; Auguste, Evan; Jean-Louis, Girardin; McFarlane, Samy I

2018-01-01

The primary occupation of a worker can play an important role in achieving good sleep, as well as good physical and mental health. Shift Work Sleep Disorder (SWSD) is a condition that results from working atypical shifts (i.e. other than the typical 9 am to 5 pm schedule). Individuals who manifest SWSD usually complaint of trouble sleeping, excessive sleepiness and fatigue which interfere with overall functioning. Misalignment of circadian timing system results in undesirable health consequences. Among shift workers, good sleep is essential for efficient functioning. Disturbed sleep is associated with anxiety, depression, poor physical and mental health and eventually, leads to impaired quality of life. The economic burden of undiagnosed, under-and untreated shift work is high. The healthcare workers and policymakers can play a pivotal role in dealing with this issue by educating the public and providing them with adequate privileges to perform their work. PMID:29517053

Interleukin-6 Level among Shift and Night Workers in Japan: Cross-Sectional Analysis of the J-HOPE Study.

PubMed

Amano, Hoichi; Fukuda, Yoshiharu; Yokoo, Takashi; Yamaoka, Kazue

2018-03-27

Shift workers have a high risk of cardiovascular disease (CVD). Systemic inflammation measured has been associated with the risk of CVD onset, in addition to classical risk factors. However, the association between work schedule and inflammatory cytokine levels remains unclear. The purpose of this study was to examine the association between work schedule and interleukin-6 (IL-6)/high-sensitivity C-reactive protein (hs-CRP) levels among Japanese workers. The present cross-sectional study was a part of the Japanese Study of Health, Occupation and Psychosocial Factors Related Equity (J-HOPE). A total of 5259 persons who measured inflammatory cytokine were analyzed in this study. One-way analysis of variance was used to test log-transformed IL-6/hs-CRP differences by work schedule. Multiple regression analysis was used to examine the difference adjusted for other possible CVD risk factors. There were 3660 participants who had a regular work schedule; the remaining schedules were shift work without night work for 181 participants, shift work with night work for 1276 participants, and only night work for 142 participants. The unadjusted model showed that only night workers were significantly related to high levels of IL-6 compared with regular workers. Even in the multiple regression analysis, the higher level of IL-6 among only night workers remained significant (β=0.058, P=0.01). On the contrary, hs-CRP was not. The present study revealed that only night shift work is significantly associated with high levels of IL-6 in Japanese workers. These observations help us understand the mechanism for the association between work schedule and CVD onset.

Noise exposure and hearing loss among sand and gravel miners.

PubMed

Landen, Deborah; Wilkins, Steve; Stephenson, Mark; McWilliams, Linda

2004-08-01

The objectives of this study were to describe workplace noise exposures, risk factors for hearing loss, and hearing levels among sand and gravel miners, and to determine whether full shift noise exposures resulted in changes in hearing thresholds from baseline values. Sand and gravel miners (n = 317) were interviewed regarding medical history, leisure-time and occupational noise exposure, other occupational exposures, and use of hearing protection. Audiometric tests were performed both before the work shift (following a 12-hour noise-free interval) and immediately following the work shift. Full shift noise dosimetry was conducted. Miners' noise exposures exceeded the Recommended Exposure Limit (REL) of the National Institute for Occupational Safety and Health (NIOSH) for 69% of workers, and exceeded the Mine Safety and Health Administration's action level for enrollment in a hearing conservation program for 41% of workers. Significantly higher noise exposures occurred among employees of small companies, among workers with a job classification of truck driver, among males, and among black workers. Hearing protection usage was low, with 48% of subjects reporting that they never used hearing protection. Hearing impairment, as defined by NIOSH, was present among 37% of 275 subjects with valid audiograms. Black male workers and white male workers had higher hearing thresholds than males from a comparison North Carolina population unexposed to industrial noise. Small but statistically significant changes in hearing thresholds occurred following full shift noise exposure among subjects who had good hearing sensitivity at baseline. In a logistic regression model, age and history of a past noisy job were significant predictors of hearing impairment. Overall, sand and gravel workers have excessive noise exposures and significant hearing loss, and demonstrate inadequate use of hearing protection. Well-designed hearing conservation programs, with reduction of noise exposure, are clearly needed.

Sleep quality and quality of life in female shift-working nurses.

PubMed

Shao, Ming-Fen; Chou, Yu-Ching; Yeh, Mei-Yu; Tzeng, Wen-Chii

2010-07-01

This paper is a report of a study of the factors that influence sleep quality and quality of life among shift-working nurses and the relationship between their sleep quality and quality of life. Although shift-working nurses strive to adapt their life schedules to shift rotations, they tend to suffer from severe sleep disturbances and increased rates of cancer, cardiovascular diseases, digestive disease and irregular menstrual cycles. Poor sleep is also associated with medical errors and occupational injuries. A cross-sectional study was conducted in 2008 with a convenience sample of 435 female nurses from five regional hospitals in Taiwan. Data were collected on sleep quality and quality of life using the Pittsburgh Sleep Quality Index and World Health Organization Quality of Life Instrument-BREF Taiwan version respectively. Data were analysed using descriptive statistics, independent t-tests, analysis of variance and Pearson correlations. The majority of female shift workers (57%) had global sleep-quality scores > or = 5, indicating poor sleep and all mean scores in four domains of the quality-of-life measure were statistically significantly lower than those of females in Taiwan's general population. Scores for poor sleep quality and quality of life were related to premenstrual dysphoria, occupational injury, illness and medication use. In addition, the associations between scores on the sleep-quality and quality-of-life scales were statistically significantly inversely correlated. Advice should be included in both undergraduate programmes and continuing education to help nurses to recognize and improve their own sleep quality and life quality managers should create a supportive environment to encourage shift-working nurses to engage in healthy behaviours.

Musculoskeletal and neurological injuries associated with work organization among immigrant Latino women manual workers in North Carolina.

PubMed

Arcury, Thomas A; Cartwright, Michael S; Chen, Haiying; Rosenbaum, Daryl A; Walker, Francis O; Mora, Dana C; Quandt, Sara A

2014-04-01

This analysis examines the associations of work organization attributes among Latino women in manual occupations with musculoskeletal and neurological injuries. Participants included 234 women in western North Carolina. Outcome measures included epicondylitis, rotator cuff syndrome, back pain, and carpal tunnel syndrome. Independent measures included indicators of job demand, job control, and job support, as well as personal characteristics. Latina workers commonly experienced epicondylitis, rotator cuff syndrome, back pain, and CTS. Awkward posture and decision latitude were associated with epicondylitis. Rotator cuff syndrome was associated with awkward posture and psychological demand. Awkward posture and psychological demand, and decreased skill variety and job control were related to CTS. Work organization factors are potentially important for musculoskeletal and neurological injury among vulnerable workers. Research is required to understand the associations of work and health outcomes of these women. Policy initiatives need to consider how work organization affects health. © 2014 Wiley Periodicals, Inc.

An Evaluation of the Relationship among Urine, Air, and Hand Measures of Exposure to Bisphenol A (BPA) in US Manufacturing Workers.

PubMed

Hines, Cynthia J; Christianson, Annette L; Jackson, Matthew V; Ye, Xiaoyun; Pretty, Jack R; Arnold, James E; Calafat, Antonia M

2018-06-13

Exposure to bisphenol A (BPA) can be assessed using external and internal exposure measures. We examined the relationship between two measures of external BPA exposure (air and hand-wipe samples) and one of internal exposure (total BPA in urine) for a group of US manufacturing workers. During 2013-2014, we recruited 78 workers from six US companies that made BPA or made products with BPA. We quantified BPA in seven urine samples, two full-shift air samples and in pre- and end-shift hand-wipe samples collected from workers over 2 consecutive days. We examined correlations between creatinine-corrected urinary concentrations of total BPA (total BPACR) and BPA levels in air and hand wipes using Pearson's correlation coefficient. We also applied mixed-effects regression models to examine the relationship between total BPACR with BPA in air (urine~air model) and with BPA in end-shift hand wipes (urine~hand model), separately and together (urine~air+hand model), after adjusting for covariates. End-shift total BPACR strongly correlated with BPA in air (rp = 0.79, P < 0.0001) and nearly as strongly with BPA in end-shift hand wipes (rp = 0.75, P < 0.0001). In mixed-effect models, BPA air concentration and end-shift hand-wipe BPA level were significantly and positively associated with end-shift total BPACR (P < 0.0001 each). We found a significant effect of the Day 1 BPA air concentration on Day 2 total BPACR (P = 0.0104). When BPA air concentration and end-shift hand-wipe BPA level were in the same model, the air concentration (P < 0.0001) was more significant than the hand-wipe level (P = 0.0106). BPA levels in air and end-shift hand wipes strongly correlated with total BPACR, suggesting that both inhalation and dermal contract were likely exposure routes; however, inhalation, on average, appeared to be a more dominant exposure route than dermal contact for these manufacturing workers.

Urinary 1-hydroxypyrene and 8-hydroxydeoxyguanosine levels among coke-oven workers for 2 consecutive days.

PubMed

Nguyen, Thi-To-Uyen; Kawanami, Shoko; Kawai, Kazuaki; Kasai, Hiroshi; Li, Yun-Shan; Inoue, Jinro; Ngoan, Le Tran; Horie, Seichi

2014-01-01

This study evaluated the levels of exposure to polycyclic aromatic hydrocarbons (PAHs) and their relationship with oxidative DNA damage among Vietnamese coke-oven workers. We collected urine from 36 coke-oven workers (exposed group) at the beginning and end of the shift on 2 consecutive days. We also collected urine from 78 medical staff (control group). Information was collected by questionnaire about smoking status, drinking habit, and working position. Urinary 1-hydroxypyrene (1-OHP) and 8-hydroxydeoxyguanosine (8-OH-dG) were measured using HPLC. All statistical analyses were performed with SPSS version 19. Urinary 1-OHP was significantly higher in the coke-oven workers than in the control group (p<0.05). Top-oven workers had the highest levels of internal exposure to PAHs, followed by side-oven and then bottom-oven workers (5.41, 4.41 and 1.35 ng/mg creatinine, respectively, at the end of the shift on day 2). Urinary 8-OH-dG was significantly higher in top- and side-oven workers at the end of the shift on day 2 (4.63 and 5.88 ng/mg creatinine, respectively) than in the control group (3.85 ng/mg creatinine). Based on a multi-regression analysis, smoking status had a significant effect on urinary 8-OH-dG (p=0.049). Urinary 1-OHP tended to have a positive correlation with urinary 8-OH-dG (p=0.070). Vietnamese coke-oven workers were exposed to PAHs during their work shift. Urinary 1-OHP exceeded the recommended limit, and elevated oxidative DNA damage occurred in top- and side-oven workers on the second day of work. A tendency for positive correlation was found between urinary 1-OHP and urinary 8-OH-dG.

Is Shift Work Associated with Lipid Disturbances and Increased Insulin Resistance?

PubMed

Alefishat, Eman; Abu Farha, Rana

2015-11-01

Shift work is associated with higher risk of metabolic disturbances and cardiovascular diseases. There are contradictory reports on the effect of shift work on lipid parameters in the literature. No studies have investigated any possible association between shift work and the ratio of serum triglyceride to high density lipoprotein cholesterol (TG/HDL-C ratio). This ratio can be used as a predictor for insulin resistance. The main aim of the present cross-sectional study was to investigate the association between shift work and serum TG/HDL-C ratio, TG level, and HDL-C level. One hundred and forty adult Jordanian employees were recruited. Demographic data, lifestyle habits, clinical parameters, and working patterns data were documented through a well-structured questionnaire. Serum TG and HDL-C levels were measured after at least 9 hours fasting using enzymatic assay procedure. Compared with daytime workers (58 subjects), shift workers (82 subjects) displayed higher TG/HDL-C ratio (r = 0.217, P = 0.013), higher serum TG levels (r = 0.220, P = 0.012), and lower HDL-C levels (r = -0.200, P = 0.016). Among shift workers, 30.5% were found to have a TG/HDL-C ratio >3.5 compared with 8.6% of daytime workers (P = 0.002). In the present study, shift work was shown to be associated with higher TG/HDL-C ratio, higher serum TG, and lower HDL-C levels. These findings might indicate that shift work is associated with increased insulin resistance and consequently higher risk of metabolic syndrome and cardiovascular diseases.

The Soul of Invention

ERIC Educational Resources Information Center

Nelson, Scott Reynolds

2013-01-01

Technology shifts gears. The workers who control it need to learn how to shift gears, too. Workers brought up with universal schooling would respect authority, learn enough "geometry and mechanics" to use in their trades, keep invention alive, and finally see through "the interested complaints of faction and sedition." In other…

The effect of shift work on red blood cell distribution width.

PubMed

Loprinzi, Paul D

2015-04-01

Limited research demonstrates that shift work (e.g., evening shift, night shift, rotating shift) increases the risk of certain health outcomes, such as hypertriglyceridemia and metabolic syndrome. Red blood cell distribution width (RDW), which is commonly assessed and reported by physicians, is a novel biomarker of cardiovascular disease. However, no study has examined the association of shift work on RDW, which was the purpose of this study. Data from the 2005-2010 NHANES were used. RDW was assessed from a blood sample; shift work was assessed from a questionnaire, and various demographic, behavioral/psychological, occupational, and biological parameters were included as covariates. The fully adjusted model showed that the odds of having an elevated RDW for women on rotating shift vs. day shift increased by 46% (OR=1.46; 95% CI: 1.03-2.08). Women on a rotating shift had increased odds of having an elevated RDW, which is concerning as elevated RDW increases the risk of cardiovascular disease and mortality. Health care professionals are encouraged to include questions about organization of work schedules and their tolerance of such schedules during the patient's consultation. Copyright © 2015 Elsevier Inc. All rights reserved.

A cross-sectional study of shift work, sleep quality and cardiometabolic risk in female hospital employees.

PubMed

Lajoie, P; Aronson, K J; Day, A; Tranmer, J

2015-03-10

Investigating the potential pathways linking shift work and cardiovascular diseases (CVD), this study aimed to identify whether sleep disturbances mediate the relationship between shift work and the metabolic syndrome, a cluster of CVD risk factors. Cross-sectional study. A tertiary-level, acute care teaching hospital in Southeastern Ontario, Canada. Female hospital employees working a shift schedule of two 12 h days, two 12 h nights, followed by 5 days off (n=121) were compared with female day-only workers (n=150). Each of the seven components of the Pittsburgh Sleep Quality Index (PSQI) was measured. Of these, PSQI global score, sleep latency and sleep efficiency were examined as potential mediators in the relationship between shift work and the metabolic syndrome. Shift work status was associated with poor (>5) PSQI global score (OR=2.10, 95% CI 1.20 to 3.65), poor (≥2) sleep latency (OR=2.18, 95% CI 1.23 to 3.87) and poor (≥2) sleep efficiency (OR=2.11, 95% CI 1.16 to 3.84). Although shift work was associated with the metabolic syndrome (OR=2.29, 95% CI 1.12 to 4.70), the measured components of sleep quality did not mediate the relationship between shift work and the metabolic syndrome. Women working in a rapid forward rotating shift pattern have poorer sleep quality according to self-reported indicators of the validated PSQI and they have a higher prevalence of the metabolic syndrome compared with women who work during the day only. However, sleep quality did not mediate the relationship between shift work and the metabolic syndrome, suggesting that there are other psychophysiological pathways linking shift work to increased risk for CVD. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

A cross-sectional study of shift work, sleep quality and cardiometabolic risk in female hospital employees

PubMed Central

Aronson, K J; Day, A; Tranmer, J

2015-01-01

Objectives Investigating the potential pathways linking shift work and cardiovascular diseases (CVD), this study aimed to identify whether sleep disturbances mediate the relationship between shift work and the metabolic syndrome, a cluster of CVD risk factors. Design Cross-sectional study. Setting A tertiary-level, acute care teaching hospital in Southeastern Ontario, Canada. Participants Female hospital employees working a shift schedule of two 12 h days, two 12 h nights, followed by 5 days off (n=121) were compared with female day-only workers (n=150). Primary and secondary outcome measures Each of the seven components of the Pittsburgh Sleep Quality Index (PSQI) was measured. Of these, PSQI global score, sleep latency and sleep efficiency were examined as potential mediators in the relationship between shift work and the metabolic syndrome. Results Shift work status was associated with poor (>5) PSQI global score (OR=2.10, 95% CI 1.20 to 3.65), poor (≥2) sleep latency (OR=2.18, 95% CI 1.23 to 3.87) and poor (≥2) sleep efficiency (OR=2.11, 95% CI 1.16 to 3.84). Although shift work was associated with the metabolic syndrome (OR=2.29, 95% CI 1.12 to 4.70), the measured components of sleep quality did not mediate the relationship between shift work and the metabolic syndrome. Conclusions Women working in a rapid forward rotating shift pattern have poorer sleep quality according to self-reported indicators of the validated PSQI and they have a higher prevalence of the metabolic syndrome compared with women who work during the day only. However, sleep quality did not mediate the relationship between shift work and the metabolic syndrome, suggesting that there are other psychophysiological pathways linking shift work to increased risk for CVD. PMID:25757950

Outcome of Expedited Rotator Cuff Surgery in Injured Workers: Determinants of Successful Recovery.

PubMed

Razmjou, Helen; Boljanovic, Dragana; Lincoln, Sandra; Holtby, Richard; Gallay, Stephen; Henry, Patrick; Macritchie, Iona; Borthwick, Cheryl; Mayer, Lauren; Roknic, Carolyn; Shore, Deborah; Kamino, Allison; Grossman, Julie; Hill, Joanne; Singh, Gargi; Travers, Niki; Yanofsky, Loraine; Wilson, Marni; Sumar, Shellina; Savona, Alicia; De Medeiros, Filomena; Mann, Helen; Champsi, Aisha; Chau, Stefanie; Medeiros, Danielle; Richards, Robin R

2017-05-01

Work-related rotator cuff injuries are a common cause of disability and employee time loss. To examine the effectiveness of expedited rotator cuff surgery in injured workers who underwent rotator cuff decompression or repair and to explore the impact of demographic, clinical, and psychosocial factors in predicting the outcome of surgery. Case series; Level of evidence, 4. Injured workers who were seen at a shoulder specialty program and who underwent expedited arthroscopic rotator cuff decompression or repair were observed for a period of 6 to 12 months based on their type of surgery and recovery trajectory. The primary outcome measure was the American Shoulder and Elbow Surgeons (ASES) Standardized Shoulder Assessment Form. The impact of surgery was assessed by whether the change in the ASES score exceeded the minimal clinically important difference (MCID) of 17 points. Secondary outcomes were range of motion (ROM), medication consumption, and work status. One hundred forty-six patients (43 women [29%], 103 men [71%]; mean age, 52 years; SD, 8 years) completed the study. Sixty-seven (46%) patients underwent rotator cuff repair. The mean time between the date the patient consented to have surgery and the date of surgery was 82 (SD, 44) days. There was a statistically significant improvement in ASES score and ROM and work status (52 returned to regular duties and 59 to modified duties) ( P < .0001). Eighty-four percent (n = 122) of patients exceeded the MCID of 17 points. Individual factors that affected patient overall disability were preoperative ASES, work status prior to surgery, access to care, and autonomy at work. Achieving a minimal clinically meaningful change was influenced by perceived access to care, autonomy and stress at work, and overall satisfaction with the job. Expedited rotator cuff surgery improved disability, ROM, and work status in injured workers. Successful recovery after work-related shoulder injuries may further be facilitated by improving the psychosocial work environment and increasing access to care.

The effect of long and short head biceps loading on glenohumeral joint rotational range of motion and humeral head position.

PubMed

McGarry, Michelle H; Nguyen, Michael L; Quigley, Ryan J; Hanypsiak, Bryan; Gupta, Ranjan; Lee, Thay Q

2016-06-01

To evaluate the effect of loading the long and short heads of the biceps on glenohumeral range of motion and humeral head position. Eight cadaveric shoulders were tested in 60° abduction in the scapula and coronal plane. Muscle loading was applied based on cross-sectional area ratios. The short and long head of the biceps were loaded individually followed by combined loading. Range of motion was measured with 2.2 Nm torque, and the humeral head apex position was measured using a MicroScribe. A paired t test with Bonferroni correction was used for statistics. Long head loading decreased internal rotation in both the scapular (17.9 %) and coronal planes (5.7 %) and external rotation in the scapular plane (2.6 %) (P < 0.04). With only short head loading, maximum internal rotation was significantly increased in the scapular and coronal plane. Long head and short head loading shifted the humeral head apex posteriorly in maximum internal rotation in both planes with the long head shift being significantly greater than the short head. Long head loading also shifted the humeral apex inferiorly in internal rotation and inferiorly posteriorly in neutral rotation in the scapular plane. With the long head unloaded, there was a significant superior shift with short head loading in both planes. Loading the long head of the biceps had a much greater effect on glenohumeral range of motion and humeral head shift than the short head of the biceps; however, in the absence of long head loading, with the short head loaded, maximum internal rotation increases and the humeral head shifts superiorly, which may contribute to impingement following tenodesis of the long head of the biceps. These small changes in rotational range of motion and humeral head position with biceps tenodesis may not lead to pathologic conditions in low-demand patients; however, in throwers, biceps tenodesis may lead to increased contact pressures in late-cocking and deceleration that will likely translate to decreased performance therefore every effort should be made to preserve the biceps-labral complex.

Sleep quality in nurses: a randomized clinical trial of day and night shift workers.

PubMed

Niu, Shu-Fen; Chu, Hsin; Chung, Min-Huey; Lin, Chun-Chieh; Chang, Yu-Shiun; Chou, Kuei-Ru

2013-07-01

The study investigated the number of days off nurses working night shifts need to recover their sleep quality to the level of daytime workers during their days off. This study included 30 day-shift nurses and 32 night-shift nurses. It was conducted as a randomized clinical trial in the medical and surgical wards of a medical center in northern Taiwan in May and June 2010 using sleep diaries and sleep parameters collected by actigraphy on different workdays and days off. On workdays, the night-shift group had significantly less total sleep time (TST) on Day 5 and significantly lower sleep efficiency (SE) on Day 3 than the day-shift group. TSTs of the two groups on days off were higher than those on workdays. On the 4th consecutive day off, higher TST, a decrease in WASO, and an increase in SE suggests that the night-shift group had recovered their sleep quality to the level of the day-shift group on their days off. The SE of the night-shift group exceeded that of the day-shift group after the 4th consecutive day off, though the difference was not statistically significant in the present study. Based on these data, it is recommended that night-shift workers arrange a period of at least 4 days off after 5 consecutive night shifts and at least 5 days off if the staff who have previously worked night shifts are being assigned a set of different shifts.

Methodological aspects of shift-work research.

PubMed

Knutsson, Anders

2004-01-01

A major issue in shift-work research is to understand the possible ways in which shift work can impact performance and health. Nearly all body functions, from those of the cellular level to those of the entire body, are circadian rhythmic. Disturbances of these rhythms as well as the social consequences of odd work hours are of importance for the health and well-being of shift workers. This article reviews a number of common methodological issues which are of relevance to epidemiological studies in this area of research. It discusses conceptual problems regarding the use of the term "shift work," and it underscores the need to develop models that explain the mechanisms of disease in shift workers.

Exposure to varying concentration of fungal spores in grain storage godowns and its effect on the respiratory function status among the workers.

PubMed

Chattopadhyay, Bhaskar P; Das, Satadal; Adhikari, Atin; Alam, Jane

2007-06-01

Grain storage depot workers suffer from different respiratory problems after getting the exposure to storage grain dust. Which is a mixture of pesticides, fungi, silica, bacteria, spores, storage mites, animal hairs, pollens etc. The present study was undertaken to evaluate the fungal spore concentration in summer and winter season as well as the pulmonary function status of the workers; studies are limited in our country. In summer and winter seasons, air sampling was done to measure the airborne fungal spore concentration inside the godowns by Rotorod sampler, UK. Aspergilla, Alternaria, Drechslera, Epicoccum, Nigrospora, Periconia were very much common and found higher in winter compared to summer. The respiratory functional status was assessed in two groups of workers of the same storage grain depot (total n=316) in summer (n=136) and in winter (n=180). List of the workers was collected from the authority and randomly selected every alternate worker and divide them for the studies in summer and winter seasons. Slow Vital Capacity (SVC), Forced Vital Capacity (FVC), and Peak Expiratory Flow Rate (PEFR) were recorded and Forced Expiratory Volume in one second (FEV1), FEV1% and different flow rates were calculated. The Immunoglobulin- E (IgE) level in the blood serum was assessed on post shift pulmonary function tests (PFT) decreased workers. The age, height and weight of the same categories of workers of both studies are highly comparable. Mean PFT values in summer found higher than winter. A gradual decrement of values were found as age was increased but not with duration of exposure. Post-shift PFT was carried in 21.8% (69) workers of which 46.4% (32) workers showed the decrement of values. The serum IgE level of the post-shift PFT decreased subjects was found more than 250 IU/ml in 53.1% (17) workers. Restrictive, obstructive and combined types of respiratory impairments were noticed among the workers. Presence of different spores in varying concentration in the working atmosphere may be responsible for the post shift decrement of PFT, allergic symptoms, high IgE level and respiratory impairments among the workers.

Shifting responsibility to workers: the future of retirement adequacy in the United States.

PubMed

Steinberg, Allen; Lucas, Lori

2004-01-01

While many 401(k) participants at large companies can expect replacement of nearly 100% of preretirement income, not all workers participate in their 401(k) plan. Moreover, the authors show that even among participants, the extent of retirement preparedness depends on defined benefit (DB) plan coverage and retiree medical benefit generosity. Given recent trends in the elimination of DB plans and retiree medical subsidies and the voluntary nature of 401(k) participation, retirement income responsibility is increasingly shifting to workers. The authors discuss how employers might help workers meet their retirement income needs in this changing environment.

Compressional Alfvén eigenmodes in rotating spherical tokamak plasmas

DOE PAGES

Smith, H. M.; Fredrickson, E. D.

2017-02-07

Spherical tokamaks often have a considerable toroidal plasma rotation of several tens of kHz. Compressional Alfvén eigenmodes in such devices therefore experience a frequency shift, which if the plasma were rotating as a rigid body, would be a simple Doppler shift. However, since the rotation frequency depends on minor radius, the eigenmodes are affected in a more complicated way. The eigenmode solver CAE3B (Smith et al 2009 Plasma Phys. Control. Fusion 51 075001) has been extended to account for toroidal plasma rotation. The results show that the eigenfrequency shift due to rotation can be approximated by a rigid body rotationmore » with a frequency computed from a spatial average of the real rotation profile weighted with the eigenmode amplitude. To investigate the effect of extending the computational domain to the vessel wall, a simplified eigenmode equation, yet retaining plasma rotation, is solved by a modified version of the CAE code used in Fredrickson et al (2013 Phys. Plasmas 20 042112). Lastly, both solving the full eigenmode equation, as in the CAE3B code, and placing the boundary at the vessel wall, as in the CAE code, significantly influences the calculated eigenfrequencies.« less

Fluid losses and hydration status of industrial workers under thermal stress working extended shifts

PubMed Central

Brake, D; Bates, G

2003-01-01

Aims: To assess whether workers under significant thermal stress necessarily dehydrated during their exposure and whether "involuntary dehydration" was inevitable, as supported by ISO 9866 and other authorities. Other objectives were to quantify sweat rates against recommended occupational limits, to develop a dehydration protocol to assist with managing heat exposures, and to understand the role of meal breaks on extended shifts in terms of fluid replacement. Methods: A field investigation to examine the fluid consumption, sweat rates, and changes in the hydration state of industrial workers on extended (10, 12, and 12.5 hour) shifts under significant levels of thermal stress (wet bulb globe temperature (WBGT) >28°C) was conducted on 39 male underground miners. Urinary specific gravity was measured before, during, and at the completion of the working shift. Environmental conditions were measured hourly during the shift. Fluid replacement was measured during the working periods and during the meal breaks. Results: Average environmental conditions were severe (WBGT 30.9°C (SD 2.0°C), range 25.7–35.2°C). Fluid intake averaged 0.8 l/h during exposure (SD 0.3 l/h, range 0.3–1.5 l/h). Average urinary specific gravity at start, mid, and end of shift was 1.0251, 1.0248, and 1.0254 respectively; the differences between start and mid shift, mid and end shift, and start and end shift were not significant. However, a majority of workers were coming to work in a moderately hypohydrated state (average urinary specific gravity 1.024 (SD 0.0059)). A combined dehydration and heat illness protocol was developed. Urinary specific gravity limits of 1.022 for start of shift and 1.030 for end of shift were selected; workers exceeding these values were not allowed into the workplace (if the start of shift limit was exceeded) or were retested prior to their next working shift (if the end of shift limit was exceeded). A target of 1.015 as a euhydrated state for start of shift was adopted for workforce education. Conclusions: This study found that "involuntary dehydration" did not occur in well informed workers, which has implications for heat stress standards that do not make provision for full fluid replacement during heat exposure. Fluid replacement during meal breaks was not significantly increased above fluid replacement rates during work time, with implications for the duration and spacing of meal breaks on long shifts. Testing of urinary specific gravity was found to be a good indication of hydration status and a practical method of improving workforce awareness and understanding of this important risk factor. Approximately 10 000 dehydration tests have been conducted under the dehydration protocol in a workforce of 2000 persons exposed to thermal stress and has proved practical and reliable. PMID:12554834

[Stress and work-related injuries].

PubMed

Tomei, G; Capozzella, A; Rosati, M V; Tomei, F; Rinaldi, G; Chighine, A; di Marzio, A; Sacco, C; Pimpinella, B; Suppi, A; Scala, B; Casale, T; Sancini, A

2015-01-01

The aim of this study was to evaluate in scientific literature the more frequent work injuries among the occupational categories examined (construction workers, healthcare workers, night workers and shift work, drivers) and to identify occupational stressors that increase the risk of injury. The research was conducted through review of the scientific literature between 1990 and 2014. Two hundred articles were found of which 42 selected in the following categories: construction workers, healthcare workers, shift workers, lorry drivers. The movement of machinery and working at height are due to injury for building sector and they were positively correlated with physical (r = 0,206) and mental (r = 0,254) stress. In health workers the injuries are more frequently bruises and sprains (50%). Studies showed a higher rate of injury in a group of shift workers compared to a control group on a rota basis (p <0.0001). Road accidents for drivers represent the most frequent cause of injury of which 13% comes from falling asleep, while 31% from distractions (OR = 3.16; CI = 1:22 to 8:24). Nurses have frequent injuries due to bruises, lumbago, punctures with needles and surgical wounds. Construction workers often suffer serious injury derived from falls at height, handling machinery. For workers on a rota basis, injuries are often related to lack of sleep. Road accidents in drivers are the most common injuries. A synergistic action finalized to promote health and safety organization, to ensure a work environment more secure, is advisable.

A laboratory comparison of clockwise and counter-clockwise rapidly rotating shift schedules, part II : performance : final report.

DOT National Transportation Integrated Search

2002-07-01

INTRODUCTION. Many Air Traffic Control Specialists (ATCSs) work a relatively unique counter-clockwise, rapidly rotating shift schedule. Although arguments against these kinds of schedules are prevalent in the literature, few studies have examined rot...

Associations between shift schedule characteristics with sleep, need for recovery, health and performance measures for regular (semi-)continuous 3-shift systems.

PubMed

van de Ven, Hardy A; Brouwer, Sandra; Koolhaas, Wendy; Goudswaard, Anneke; de Looze, Michiel P; Kecklund, Göran; Almansa, Josue; Bültmann, Ute; van der Klink, Jac J L

2016-09-01

In this cross-sectional study associations were examined between eight shift schedule characteristics with shift-specific sleep complaints and need for recovery and generic health and performance measures. It was hypothesized that shift schedule characteristics meeting ergonomic recommendations are associated with better sleep, need for recovery, health and performance. Questionnaire data were collected from 491 shift workers of 18 companies with 9 regular (semi)-continuous shift schedules. The shift schedule characteristics were analyzed separately and combined using multilevel linear regression models. The hypothesis was largely not confirmed. Relatively few associations were found, of which the majority was in the direction as expected. In particular early starts of morning shifts and many consecutive shifts seem to be avoided. The healthy worker effect, limited variation between included schedules and the cross-sectional design might explain the paucity of significant results. Copyright © 2016 Elsevier Ltd. All rights reserved.

Self-assessed quality of sleep, occupational health, working environment, illness experience and job satisfaction of female nurses working different combination of shifts.

PubMed

Sveinsdóttir, Herdis

2006-06-01

The aim of this study was to describe and compare the self-assessed quality of sleep, occupational health, working environment, illness experience and job satisfaction among female nurses working different combinations of shifts. Evidence from several studies indicates that there is an association between the disruption of the circadian cycle caused by shift work and adverse health effects. A cross-sectional design was used with a sample of 348 nurses drawn from the registry of the Icelandic Nurses' Association, representing 17% of the workforce of Icelandic nurses. A self-administered questionnaire, measuring occupational health, quality of sleep, the illness experience, job satisfaction and working environment was used. Data were analysed according to type of shift (days only, rotating days/evenings, rotating days/evenings/nights) by use of analysis of variance and chi-square. No difference was found between participants based on type of shift with regard to the illness experience, job satisfaction and quality of sleep. Nurses working rotating day/evening/night shifts reported a longer working day, more stressful environmental risk factors, more strenuous work and that they were less able to control their work-pace. In general, the nurses reported low severity of symptoms; however, nurses working rotating days/evenings shifts experienced more severe gastrointestinal and musculoskeletal symptoms when compared with others. This was explained by the short rest period provided for between evening and morning shifts. In general Icelandic nurses are satisfied with their work and their shift assignment does not seem to pathologically disrupt their circadian cycle. Nevertheless, nursing directors are advised to look more closely at the organization of nurses' work during night shifts, as well as the rest period for nurses changing from evening to day shifts.

[Mental health status in railway female workers and its occupational influencing factors].

PubMed

Ji, F L; Liu, Z M; Liu, Z S; Zou, J F; Yu, W L; Li, H M; Li, J; Kong, L M; Jiang, Q

2018-02-20

Objective: To investigate the mental health status of railway female workers and related influencing factors, and to provide a scientific strategy for labor protection regulations in railway female workers. Methods: Cluster sampling was used to select 5033 female workers from Jinan, Nanning, Qinghai-Tibet, and Wuhan railway systems in China from January to August, 2016. A uniform reproductive health questionnaire, as well as the Symptom Checklist-90 (SCL-90) , was used to investigate their general information (age, marital status, education level, and family income) , work type (day shift, night shift, or work on shift) , work position, and the presence or absence of exposure to occupational hazardous factors. The score on each factor of SCL-90 and the positive rate of mental health status were calculated. Results: The positive rate of mental health status was 10.6% in railway female workers. The workers exposed to occupational hazardous factors had a significantly higher positive rate of mental health status than those not exposed to occupational hazardous factors (14.20% vs 8.02%, P <0.01) . There were significant differences in the positive rate of mental health status between workers with different ages, marital status, education levels, histories of abortion, or annual family income levels ( P <0.01) . The scores of somatization (1.54±0.62) and horror (1.28±0.47) in SCL-90 were significantly higher than the Chinese adult norm ( P <0.01) . The multivariate logistic regression analysis showed that exposure to occupational hazardous factors, night shift, overwork, and carrying heavy objects were associated with mental health problems ( OR =1.797, 95% CI : 1.393-2.318; OR =0.641, 95% CI : 0.498-0.827; OR =0.586, 95% CI : 0.439-0.783; OR =0.580, 95% CI : 0.378-0.890) . Conclusion: Railway female workers have lower levels of mental health than the general population and are under significant occupational stress. Exposure to occupational hazardous factors, night shift, overwork, and carrying heavy objects are associated with the development of mental health problems in railway female workers.

Polarization splitter and polarization rotator designs based on transformation optics.

PubMed

Kwon, Do-Hoon; Werner, Douglas H

2008-11-10

The transformation optics technique is employed in this paper to design two optical devices - a two-dimensional polarization splitter and a three-dimensional polarization rotator for propagating beams. The polarization splitter translates the TM- and the TE-polarized components of an incident beam in opposite directions (i.e., shifted up or shifted down). The polarization rotator rotates the polarization state of an incoming beam by an arbitrary angle. Both optical devices are reflectionless at the entry and exit interfaces. Design details and full-wave simulation results are provided.

Vacuum Bloch-Siegert shift in Landau polaritons with ultra-high cooperativity

NASA Astrophysics Data System (ADS)

Li, Xinwei; Bamba, Motoaki; Zhang, Qi; Fallahi, Saeed; Gardner, Geoff C.; Gao, Weilu; Lou, Minhan; Yoshioka, Katsumasa; Manfra, Michael J.; Kono, Junichiro

2018-06-01

A two-level system resonantly interacting with an a.c. magnetic or electric field constitutes the physical basis of diverse phenomena and technologies. However, Schrödinger's equation for this seemingly simple system can be solved exactly only under the rotating-wave approximation, which neglects the counter-rotating field component. When the a.c. field is sufficiently strong, this approximation fails, leading to a resonance-frequency shift known as the Bloch-Siegert shift. Here, we report the vacuum Bloch-Siegert shift, which is induced by the ultra-strong coupling of matter with the counter-rotating component of the vacuum fluctuation field in a cavity. Specifically, an ultra-high-mobility two-dimensional electron gas inside a high-Q terahertz cavity in a quantizing magnetic field revealed ultra-narrow Landau polaritons, which exhibited a vacuum Bloch-Siegert shift up to 40 GHz. This shift, clearly distinguishable from the photon-field self-interaction effect, represents a unique manifestation of a strong-field phenomenon without a strong field.

Factors associated with severe occupational injuries at mining company in Zimbabwe, 2010: a cross-sectional study.

PubMed

Chimamise, Chipo; Gombe, Notion Tafara; Tshimanga, Mufuta; Chadambuka, Addmore; Shambira, Gerald; Chimusoro, Anderson

2013-01-01

Injury rate among mining workers in Zimbabwe was 789/1000 workers in 2008. The proportion of severe occupational injuries increased from 18% in 2008 to 37% in 2009. We investigated factors associated with severe injuries at the mine. An unmatched 1:1 case-control study was carried out at the mine, a case was any worker who suffered severe occupational injury at the mine and was treated at the mine or district hospital from January 2008 to April 2010, a control was any worker who did not suffer occupational injury during same period. We randomly selected 156 cases and 156 controls and used interviewer administered questionnaires to collect data from participants. Majority of cases, 155(99.4%) and of controls 142(91%) were male, 127(81.4%) of cases and 48(30.8%) of controls worked underground. Majority (73.1%) of severe occupational injuries occurred during night shift. Underground temperatures reached 500C. Factors independently associated with getting severe occupational injuries included working underground (AOR=10.55; CI 5.97-18.65), having targets per shift (AOR=12.60; CI 3.46-45.84), inadequate PPE (AOR=3.65 CI 1.34-9.89) and working more than 8 hours per shift (AOR=8.65 CI 2.99-25.02). Having targets exerts pressure to perform on workers. Prolonged working periods decrease workers' attention and concentration resulting in increased risk to severe injuries as workers become exhausted, lose focus and alertness. Underground work environment had environmental hazards so managers to install adequate ventilation and provide adequate PPE. Management agreed to standardize shifts to eight hours and workers in some departments have been supplied with adequate PPE.

Shift work and cognitive aging: a longitudinal study.

PubMed

Bokenberger, Kathleen; Ström, Peter; Dahl Aslan, Anna K; Åkerstedt, Torbjörn; Pedersen, Nancy L

2017-09-01

Objectives The few studies of shift work and late life cognitive functioning have yielded mixed findings. The aim of the present study is to estimate the association between shift-work experience and change in cognitive performance before and after retirement age among older adults who were gainfully employed. Methods Five hundred and ninety five participants with no dementia were followed up for a mean of 17.6 standard deviation (SD) 8.8 years from a Swedish population-based sample. Participants had self-reported information on any type of shift-work experience (ever/never) in 1984 and measures of cognitive performance (verbal, spatial, memory, processing speed, and general cognitive ability) from up to 9 waves of cognitive assessments during 1986-2012. Night work history (ever/never) from 1998-2002 was available from a subsample (N=320). Early adult cognitive test scores were available for 77 men. Results In latent growth curve modeling, there were no main effects of "any-type" or night shift work on the mean scores or rate of change in any of the cognitive domains. An interaction effect between any-type shift work and education on cognitive performance at retirement was noted. Lower-educated shift workers performed better on cognitive tests than lower-educated day workers at retirement. Sensitivity analyses, however, indicated that the interactions appeared to be driven by selection effects. Lower-educated day workers demonstrated poorer cognitive ability in early adulthood than lower-educated shift workers, who may have selected jobs entailing higher cognitive demand. Conclusion There was no difference in late-life cognitive aging between individuals with a history of working shifts compared to those who had typical day work schedules during midlife.

Differences between Workers on Different Shifts in Rating of Client Skills.

ERIC Educational Resources Information Center

Gampel, Ezra S.

The study sought to determine if there are differences between shifts of workers in Intermediate Care Facilities in their ratings of the daily living skills of mentally retarded residents, and whether these differences reflect actual differences in performance by the residents. Staff were interviewed concerning the level of prompt required to…

Flexible working arrangements in healthcare: a comparison between managers of shift workers and 9-to-5 employees.

PubMed

Mercer, Danielle; Russell, Elizabeth; Arnold, Kara A

2014-01-01

This study examined healthcare managers' perceptions of flexible working arrangements and implementation barriers. Work-life conflict can lead to negative health implications, but flexible working arrangements can help manage this conflict. Little research has examined its implementation in 24/7/365 healthcare organizations or within groups of employees working 9 AM to 5 PM (9-5) versus shift-work hours. Questionnaires regarding perceptions to, benefits of, and barriers against flexible working arrangements were administered to managers of 9-5 workers and shift workers in an Atlantic Canadian healthcare organization. Few differences in perceptions and benefits of flexible working arrangements were found between management groups. However, results indicate that the interaction with patients and/or the immediacy of tasks being performed are barriers for shift-work managers. The nature of healthcare presents barriers for managers implementing flexible working arrangements, which differ only based on whether the job is physical (shift work) versus desk related (9-5 work).

Enhanced preference for high-fat foods following a simulated night shift.

PubMed

Cain, Sean W; Filtness, Ashleigh J; Phillips, Craig L; Anderson, Clare

2015-05-01

Shift workers are prone to obesity and associated co-morbidities such as diabetes and cardiovascular disease. Sleep restriction associated with shift work results in dramatic endocrine and metabolic effects that predispose shift workers to these adverse health consequences. While sleep restriction has been associated with increased caloric intake, food preference may also play a key role in weight gain associated with shift work. This study examined the impact of an overnight simulated night shift on food preference. Sixteen participants [mean 20.1, standard deviation (SD) 1.4 years; 8 women] underwent a simulated night shift and control condition in a counterbalanced order. On the following morning, participants were provided an opportunity for breakfast that included high- and low-fat food options (mean 64.8% and 6.4% fat, respectively). Participants ate significantly more high-fat breakfast items after the simulated night shift than after the control condition [167.3, standard error of the mean (SEM 28.7) g versus 211.4 (SEM 35.6) g; P=0.012]. The preference for high-fat food was apparent among the majority of individuals following the simulated night shift (81%), but not for the control condition (31%). Shift work and control conditions did not differ, however, in the total amount of food or calories consumed. A simulated night shift leads to preference for high-fat food during a subsequent breakfast opportunity. These results suggest that food choice may contribute to weight-related chronic health problems commonly seen among night shift workers.

Behavior of a Light Solid in a Rotating Horizontal Cylinder with Liquid Under Vibration

NASA Astrophysics Data System (ADS)

Karpunin, I. E.; Kozlova, A. N.; Kozlov, N. V.

2018-06-01

Dynamics of a cylindrical body in a rotating cavity is experimentally studied under transversal translational vibrations of the cavity rotation axis. Experiments are run at high rotation rate, when under the action of centrifugal force the body shifts to the rotation axis (the centrifuged state). In the absence of vibrations, the lagging rotation of the body is observed, due to the body radial shift from the axis of rotation caused by gravity. The body average rotation regime depends on the cavity rotation rate. The vibrations lead to the excitation of different regimes of body differential rotation (leading or lagging) associated with the excitation of its inertial oscillations. The dependence of the differential speed of the body rotation on the vibration frequency is investigated. The body dynamics has a complex character depending on the dimensionless vibration frequency. The analysis of body oscillation trajectory revealed that the body oscillatory motion consists of several modes, which contribute to the averaged dynamics of the body and the flows in the cavity.

Anterolateral Knee Extra-articular Stabilizers: A Robotic Sectioning Study of the Anterolateral Ligament and Distal Iliotibial Band Kaplan Fibers.

PubMed

Geeslin, Andrew G; Chahla, Jorge; Moatshe, Gilbert; Muckenhirn, Kyle J; Kruckeberg, Bradley M; Brady, Alex W; Coggins, Ashley; Dornan, Grant J; Getgood, Alan M; Godin, Jonathan A; LaPrade, Robert F

2018-05-01

The individual kinematic roles of the anterolateral ligament (ALL) and the distal iliotibial band Kaplan fibers in the setting of anterior cruciate ligament (ACL) deficiency require further clarification. This will improve understanding of their potential contribution to residual anterolateral rotational laxity after ACL reconstruction and may influence selection of an anterolateral extra-articular reconstruction technique, which is currently a matter of debate. Hypothesis/Purpose: To compare the role of the ALL and the Kaplan fibers in stabilizing the knee against tibial internal rotation, anterior tibial translation, and the pivot shift in ACL-deficient knees. We hypothesized that the Kaplan fibers would provide greater tibial internal rotation restraint than the ALL in ACL-deficient knees and that both structures would provide restraint against internal rotation during a simulated pivot-shift test. Controlled laboratory study. Ten paired fresh-frozen cadaveric knees (n = 20) were used to investigate the effect of sectioning the ALL and the Kaplan fibers in ACL-deficient knees with a 6 degrees of freedom robotic testing system. After ACL sectioning, sectioning was randomly performed for the ALL and the Kaplan fibers. An established robotic testing protocol was utilized to assess knee kinematics when the specimens were subjected to a 5-N·m internal rotation torque (0°-90° at 15° increments), a simulated pivot shift with 10-N·m valgus and 5-N·m internal rotation torque (15° and 30°), and an 88-N anterior tibial load (30° and 90°). Sectioning of the ACL led to significantly increased tibial internal rotation (from 0° to 90°) and anterior tibial translation (30° and 90°) as compared with the intact state. Significantly increased internal rotation occurred with further sectioning of the ALL (15°-90°) and Kaplan fibers (15°, 60°-90°). At higher flexion angles (60°-90°), sectioning the Kaplan fibers led to significantly greater internal rotation when compared with ALL sectioning. On simulated pivot-shift testing, ALL sectioning led to significantly increased internal rotation and anterior translation at 15° and 30°; sectioning of the Kaplan fibers led to significantly increased tibial internal rotation at 15° and 30° and anterior translation at 15°. No significant difference was found when anterior tibial translation was compared between the ACL/ALL- and ACL/Kaplan fiber-deficient states on simulated pivot-shift testing or isolated anterior tibial load. The ALL and Kaplan fibers restrain internal rotation in the ACL-deficient knee. Sectioning the Kaplan fibers led to greater tibial internal rotation at higher flexion angles (60°-90°) as compared with ALL sectioning. Additionally, the ALL and Kaplan fibers contribute to restraint of the pivot shift and anterior tibial translation in the ACL-deficient knee. This study reports that the ALL and distal iliotibial band Kaplan fibers restrain anterior tibial translation, internal rotation, and pivot shift in the ACL-deficient knee. Furthermore, sectioning the Kaplan fibers led to significantly greater tibial internal rotation when compared with ALL sectioning at high flexion angles. These results demonstrate increased rotational knee laxity with combined ACL and anterolateral extra-articular knee injuries and may allow surgeons to optimize the care of patients with this injury pattern.

[Shift work and night work: what effect on blood pressure?].

PubMed

Cassat, M; Wuerzner, G; Burnier, M

2015-09-09

Shift work has become more and more common for the last thirty years. By definition, shift work disturbs the circadian rhythm and the internal clock. Even if the pathophysiological mechanisms are not well understood, a greater cardiovascular risk has been attributed to shift work. Cross-sectional and cohort studies have identified an association between shift work and an elevated blood pressure. Shift workers also present a higher incidence of hypertension and progression than day workers. Unfortunately, the heterogeneity of the studies, the multiple confounding factors, as well as the complexity to achieve a suitable comparison group make it impossible to draw firm clinical evidence. Nevertheless, this population needs a medical follow-up focused on the cardiovascular risks and blood pressure.

Obesity and high blood pressure of 12-hour night shift female clean-room workers.

PubMed

Chen, Jong-Dar; Lin, Yu-Cheng; Hsiao, Shu-Tin

2010-01-01

The 12 h shift schedule is widely used in clean rooms for electronic semiconductor production in Taiwan. This study investigated the associations of obesity and metabolic syndrome (MetS) components among women working in a semiconductor manufacturing factory in North Taiwan. Workers were divided into four groups according to their work schedules and duties (i.e., office workers, day workers, fixed 12 h day shift, and fixed 12 h night shiftworkers). The subjects comprised 1838 women who voluntarily attended a health examination between August 2006 and November 2006. Their mean (+/-SD) age was 33.6 (+/-7.1) yrs and their mean duration of work was 7.4 (+/-5.2) yrs. Each subject's health-related behaviors, body mass index, and MetS components were measured and analyzed using multivariate logistic regression. Obesity and MetS were defined according to World Health Organization criteria for Asian populations and the National Cholesterol Educational Program and Adult Treatment Panel III Guidelines, respectively. The results showed that women working in the clean room on fixed 12 h night shifts had significantly elevated odds ratios for obesity (OR, 2.7; 95% CI, 1.6-4.5), central obesity (OR, 2.9; 95% CI, 1.7-5.1), and high blood pressure (OR, 2.3; 95% CI, 1.2-4.4) compared to female office workers; these results persisted after adjusting for age, smoking, drinking, education, and duration of work. We did not find any significant differences in triglyceride and high-density lipoprotein cholesterol among women working different schedules. We conclude that working fixed 12 h night shifts was associated with an increased odds ratio for obesity, central obesity, and high blood pressure among clean-room women workers. Weight reduction and blood pressure control programs should be implemented in the workplace for women working fixed 12 h night shifts.

STELLAR ROTATION EFFECTS IN POLARIMETRIC MICROLENSING

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sajadian, Sedighe, E-mail: sajadian@ipm.ir

2016-07-10

It is well known that the polarization signal in microlensing events of hot stars is larger than that of main-sequence stars. Most hot stars rotate rapidly around their stellar axes. The stellar rotation creates ellipticity and gravity-darkening effects that break the spherical symmetry of the source's shape and the circular symmetry of the source's surface brightness respectively. Hence, it causes a net polarization signal for the source star. This polarization signal should be considered in polarimetric microlensing of fast rotating stars. For moderately rotating stars, lensing can magnify or even characterize small polarization signals due to the stellar rotation throughmore » polarimetric observations. The gravity-darkening effect due to a rotating source star creates asymmetric perturbations in polarimetric and photometric microlensing curves whose maximum occurs when the lens trajectory crosses the projected position of the rotation pole on the sky plane. The stellar ellipticity creates a time shift (i) in the position of the second peak of the polarimetric curves in transit microlensing events and (ii) in the peak position of the polarimetric curves with respect to the photometric peak position in bypass microlensing events. By measuring this time shift via polarimetric observations of microlensing events, we can evaluate the ellipticity of the projected source surface on the sky plane. Given the characterizations of the FOcal Reducer and low dispersion Spectrograph (FORS2) polarimeter at the Very Large Telescope, the probability of observing this time shift is very small. The more accurate polarimeters of the next generation may well measure these time shifts and evaluate the ellipticity of microlensing source stars.« less

Randomised controlled trial of the efficacy of a blue-enriched light intervention to improve alertness and performance in night shift workers.

PubMed

Sletten, Tracey L; Ftouni, Suzanne; Nicholas, Christian L; Magee, Michelle; Grunstein, Ronald R; Ferguson, Sally; Kennaway, David J; O'Brien, Darren; Lockley, Steven W; Rajaratnam, Shantha M W

2017-11-01

Night workers often experience high levels of sleepiness due to misalignment of the sleep-wake cycle from the circadian pacemaker, in addition to acute and chronic sleep loss. Exposure to light, in particular short wavelength light, can improve alertness and neurobehavioural performance. This randomised controlled trial examined the efficacy of blue-enriched polychromatic light to improve alertness and neurobehavioural performance in night workers. Participants were 71 night shift workers (42 males; 32.8±10.5 years) who worked at least 6 hours between 22:00 and 08:00 hours. Sleep-wake logs and wrist actigraphy were collected for 1-3 weeks, followed by 48-hour urine collection to measure the circadian 6-sulphatoxymelatonin (aMT6s) rhythm. On the night following at least two consecutive night shifts, workers attended a simulated night shift in the laboratory which included subjective and objective assessments of sleepiness and performance. Workers were randomly assigned for exposure to one of two treatment conditions from 23:00 hours to 07:00 hours: blue-enriched white light (17 000 K, 89 lux; n=36) or standard white light (4000 K, 84 lux; n=35). Subjective and objective sleepiness increased during the night shift in both light conditions (p<0.05, η p 2 =0.06-0.31), but no significant effects of light condition were observed. The 17 000 K light, however, did improve subjective sleepiness relative to the 4000 K condition when light exposure coincided with the time of the aMT6s peak (p<0.05, d=0.41-0.60). This study suggests that, while blue-enriched light has potential to improve subjective sleepiness in night shift workers, further research is needed in the selection of light properties to maximise the benefits. The Australian New Zealand Clinical Trials Registry ACTRN12610000097044 (https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=320845&isReview=true). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Effects of Napping During Shift Work on Sleepiness and Performance in Emergency Medical Services Personnel and Similar Shift Workers: A Systematic Review and Meta-Analysis.

PubMed

Martin-Gill, Christian; Barger, Laura K; Moore, Charity G; Higgins, J Stephen; Teasley, Ellen M; Weiss, Patricia M; Condle, Joseph P; Flickinger, Katharyn L; Coppler, Patrick J; Sequeira, Denisse J; Divecha, Ayushi A; Matthews, Margaret E; Lang, Eddy S; Patterson, P Daniel

2018-02-15

Scheduled napping during work shifts may be an effective way to mitigate fatigue-related risk. This study aimed to critically review and synthesize existing literature on the impact of scheduled naps on fatigue-related outcomes for EMS personnel and similar shift worker groups. A systematic literature review was performed of the impact of a scheduled nap during shift work on EMS personnel or similar shift workers. The primary (critical) outcome of interest was EMS personnel safety. Secondary (important) outcomes were patient safety; personnel performance; acute states of fatigue, alertness, and sleepiness; indicators of sleep duration and/or quality; employee retention/turnover; indicators of long-term health; and cost to the system. Meta-analyses were performed to evaluate the impact of napping on a measure of personnel performance (the psychomotor vigilance test [PVT]) and measures of acute fatigue. Of 4,660 unique records identified, 13 experimental studies were determined relevant and summarized. The effect of napping on reaction time measured at the end of shift was small and non-significant (SMD 0.12, 95% CI -0.13 to 0.36; p = 0.34). Napping during work did not change reaction time from the beginning to the end of the shift (SMD -0.01, 95% CI -25.0 to 0.24; p = 0.96). Naps had a moderate, significant effect on sleepiness measured at the end of shift (SMD 0.40, 95% CI 0.09 to 0.72; p = 0.01). The difference in sleepiness from the start to the end of shift was moderate and statistically significant (SMD 0.41, 95% CI 0.09 to 0.72; p = 0.01). Reviewed literature indicated that scheduled naps at work improved performance and decreased fatigue in shift workers. Further research is required to identify the optimal timing and duration of scheduled naps to maximize the beneficial outcomes.

Work-related symptoms and dose-response relationships for personal exposures and pulmonary function among woodworkers.

PubMed

Mandryk, J; Alwis, K U; Hocking, A D

1999-05-01

Four sawmills, a wood chipping mill, and five joineries in New South Wales, Australia, were studied for the effects of personal exposure to wood dust, endotoxins. (1-->3)-beta-D-glucans, Gram-negative bacteria, and fungi on lung function among woodworkers. Personal inhalable and respirable dust sampling was carried out. The lung function tests of workers were conducted before and after a workshift. The mean percentage cross-shift decrease in lung function was markedly high for woodworkers compared with the controls. Dose-response relationships among personal exposures and percentage cross-shift decrease in lung function and percentage predicted lung function were more pronounced among joinery workers compared with sawmill and chip mill workers. Woodworkers had markedly high prevalence of regular cough, phlegm, and chronic bronchitis compared with controls. Significant associations were found between percentage cross-shift decrease in FVC and regular phlegm and blocked nose among sawmill and chip mill workers. Both joinery workers and sawmill and chip mill workers showed significant relationships between percentage predicted lung function (FVC, FEV1, FEV1/FVC, FEF25-75%) and respiratory symptoms. Wood dust and biohazards associated with wood dust are potential health hazards and should be controlled.

Promoting personal safety of building service workers: issues and challenges.

PubMed

Chen, Shelley I; Skillen, D Lynn

2006-06-01

This exploratory, descriptive study conducted at a large western Canadian university solicited perceptions of personal safety among building service workers who perform night shift work alone. Ten semi-structured interviews were conducted at approximately 10:00 p.m. or 7:00 a.m with a convenience sample of night building service workers in private or semi-private locations on the university campus. Transcribed interview data were subjected to inductive content analysis using descriptive, interpretive, and pattern coding (Miles & Huberman, 1994). Results suggest that building service night shift workers are exposed to personal safety hazards in their physical and psychosocial work environments. In addition, culturally and linguistically appropriate delivery of safety training and education about policies and procedures is required for culturally diverse building service workers. Promotion of personal safety in this heterogeneous worker population requires due diligence, assessment, and advocacy.

Quasiclassical trajectory study of the Cl+CH4 reaction dynamics on a quadratic configuration interaction with single and double excitation interpolated potential energy surface.

PubMed

Castillo, J F; Aoiz, F J; Bañares, L

2006-09-28

An ab initio interpolated potential energy surface (PES) for the Cl+CH(4) reactive system has been constructed using the interpolation method of Collins and co-workers [J. Chem. Phys. 102, 5647 (1995); 108, 8302 (1998); 111, 816 (1999); Theor. Chem. Acc. 108, 313 (2002)]. The ab initio calculations have been performed using quadratic configuration interaction with single and double excitation theory to build the PES. A simple scaling all correlation technique has been used to obtain a PES which yields a barrier height and reaction energy in good agreement with high level ab initio calculations and experimental measurements. Using these interpolated PESs, a detailed quasiclassical trajectory study of integral and differential cross sections, product rovibrational populations, and internal energy distributions has been carried out for the Cl+CH(4) and Cl+CD(4) reactions, and the theoretical results have been compared with the available experimental data. It has been shown that the calculated total reaction cross sections versus collision energy for the Cl+CH(4) and Cl+CD(4) reactions is very sensitive to the barrier height. Besides, due to the zero-point energy (ZPE) leakage of the CH(4) molecule to the reaction coordinate in the quasiclassical trajectory (QCT) calculations, the reaction threshold falls below the barrier height of the PES. The ZPE leakage leads to CH(3) and HCl coproducts with internal energy below its corresponding ZPEs. We have shown that a Gaussian binning (GB) analysis of the trajectories yields excitation functions in somehow better agreement with the experimental determinations. The HCl(v'=0) and DCl(v'=0) rotational distributions are as well very sensitive to the ZPE problem. The GB correction narrows and shifts the rotational distributions to lower values of the rotational quantum numbers. However, the present QCT rotational distributions are still hotter than the experimental distributions. In both reactions the angular distributions shift from backward peaked to sideways peaked as collision energy increases, as seen in the experiments and other theoretical calculations.

Quasiclassical trajectory study of the Cl +CH4 reaction dynamics on a quadratic configuration interaction with single and double excitation interpolated potential energy surface

NASA Astrophysics Data System (ADS)

Castillo, J. F.; Aoiz, F. J.; Bañares, L.

2006-09-01

An ab initio interpolated potential energy surface (PES) for the Cl +CH4 reactive system has been constructed using the interpolation method of Collins and co-workers [J. Chem. Phys. 102, 5647 (1995); 108, 8302 (1998); 111, 816 (1999); Theor. Chem. Acc. 108, 313 (2002)]. The ab initio calculations have been performed using quadratic configuration interaction with single and double excitation theory to build the PES. A simple scaling all correlation technique has been used to obtain a PES which yields a barrier height and reaction energy in good agreement with high level ab initio calculations and experimental measurements. Using these interpolated PESs, a detailed quasiclassical trajectory study of integral and differential cross sections, product rovibrational populations, and internal energy distributions has been carried out for the Cl +CH4 and Cl +CD4 reactions, and the theoretical results have been compared with the available experimental data. It has been shown that the calculated total reaction cross sections versus collision energy for the Cl +CH4 and Cl +CD4 reactions is very sensitive to the barrier height. Besides, due to the zero-point energy (ZPE) leakage of the CH4 molecule to the reaction coordinate in the quasiclassical trajectory (QCT) calculations, the reaction threshold falls below the barrier height of the PES. The ZPE leakage leads to CH3 and HCl coproducts with internal energy below its corresponding ZPEs. We have shown that a Gaussian binning (GB) analysis of the trajectories yields excitation functions in somehow better agreement with the experimental determinations. The HCl(v'=0) and DCl(v'=0) rotational distributions are as well very sensitive to the ZPE problem. The GB correction narrows and shifts the rotational distributions to lower values of the rotational quantum numbers. However, the present QCT rotational distributions are still hotter than the experimental distributions. In both reactions the angular distributions shift from backward peaked to sideways peaked as collision energy increases, as seen in the experiments and other theoretical calculations.

WE-EF-207-02: The Rotate-Plus-Shift C-Arm Trajectory: Theory and First Clinical Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ritschl, L; Kachelriess, M; Kuntz, J

Purpose: The proposed method enables the acquisition of a complete dataset for 3D reconstruction of C-Arm data using less than 180° rotation. Methods: Typically a C–arm cone–beam CT scan is performed using a circle–like trajectory around a region of interest. Therefore an angular range of at least 180° plus fan–angle must be covered to ensure a completely sampled data set. This fact defines some constraints on the geometry and technical specifications of a C–arm system, for example a larger C radius or a smaller C opening respectively. This is even more important for mobile C-arm devices which are typically usedmore » in surgical applications.To overcome these limitations we propose a new trajectory which requires only 180° minusfan–angle of rotation for a complete data set. The trajectory consists of three parts: A rotation of the C around a defined iso–center and two translational movements parallel to the detector plane at the begin and at the end of the rotation (rotate plus shift trajectory). This enables the acquisition of a completely sampled dataset using only 180° minus fan–angle of rotation. Results: For the evaluation of the method we show simulated and measured data. The results show, that the rotate plus shift scan yields equivalent image quality compared to the short scan which is assumed to be the gold standard for C-arm CT today. Compared to the pure rotational scan over only 165°, the rotate plus shift scan shows strong improvements in image quality. Conclusion: The proposed method makes 3D imaging using C–arms with less than 180° rotation range possible. This enables integrating full 3D functionality into a C- arm device without any loss of handling and usability for 2D imaging.« less

Occupational disease and workers' compensation: coverage, costs, and consequences.

PubMed

Leigh, J Paul; Robbins, John A

2004-01-01

Most of the costs of occupational disease are not covered by workers' compensation. First, the authors estimated the deaths and costs for all occupational disease in 1999, using epidemiological studies. Among the greatest contributors were job-related cancer, chronic respiratory disease, and circulatory disease. Second, the authors estimated the number of workers' compensation cases, costs, and deaths for 1999, using data from up to 16 states representing all regions of the country. Unlike the epidemiological studies that emphasized fatal diseases, the workers' compensation estimates emphasized nonfatal diseases and conditions like tendonitis and hernia. Comparisons of the epidemiological and workers' compensation estimates suggest that in 1999, workers' compensation missed roughly 46,000 to 93,000 deaths and 8 billion US dollars to 23 billion US dollars in medical costs. These deaths and costs represented substantial cost shifting from workers' compensation systems to individual workers, their families, private medical insurance, and taxpayers (through Medicare and Medicaid). Designing policies to reduce the cost shifting and its associated inefficiency will be challenging.

Shining a Light on Task-Shifting Policy: Exploring opportunities for adaptability in non-communicable disease management programmes in Uganda.

PubMed

Katende, Godfrey; Donnelly, Mary

2016-05-01

In terms of disease burden, many low- and middle-income countries are currently experiencing a transition from infectious to chronic diseases. In Uganda, non-communicable diseases (NCDs) have increased significantly in recent years; this challenge is compounded by the healthcare worker shortage and the underfunded health system administration. Addressing the growing prevalence of NCDs requires evidence-based policies and strategies to reduce morbidity and mortality rates; however, the integration and evaluation of new policies and processes pose many challenges. Task-shifting is the process whereby specific tasks are transferred to health workers with less training and fewer qualifications. Successful implementation of a task-shifting policy requires appropriate skill training, clearly defined roles, adequate evaluation, an enhanced training capacity and sufficient health worker incentives. This article focuses on task-shifting policy as a potentially effective strategy to address the growing burden of NCDs on the Ugandan healthcare system.

Circadian variation of melatonin, light exposure, and diurnal preference in day and night shift workers of both sexes.

PubMed

Papantoniou, Kyriaki; Pozo, Oscar J; Espinosa, Ana; Marcos, Josep; Castaño-Vinyals, Gemma; Basagaña, Xavier; Ribas, Ferran Calduch; Mirabent, Joan; Martín, Jordi; Carenys, Gemma; Martín, Celia Reyes; Middleton, Benita; Skene, Debra J; Kogevinas, Manolis

2014-07-01

Light-at-night has been shown in experimental studies to disrupt melatonin production but this has only partly been confirmed in studies of night shift workers. In this cross-sectional study, we examined the circadian variation of melatonin in relation to shift status, individual levels of light-at-night exposure, and diurnal preference, an attribute reflecting personal preference for activity in the morning or evening. One hundred and seventeen workers (75 night and 42 day) of both sexes, ages 22 to 64 years, were recruited from four companies. Participants collected urine samples from all voids over 24 hours and wore a data logger continuously recording their light exposure. Sociodemographic, occupational, lifestyle, and diurnal preference information were collected by interview. Concentrations of urinary 6-sulfatoxymelatonin (aMT6s), the main melatonin metabolite, were measured. Mean aMT6s levels were lower in night [10.9 ng/mg creatinine/hour; 95% confidence interval (CI), 9.5-12.6] compared with day workers (15.4; 95% CI, 12.3-19.3). The lowest aMT6s levels were observed in night workers with morning preference (6.4; 95% CI, 3.0-13.6). Peak time of aMT6s production occurred 3 hours later in night (08:42 hour, 95% CI, 07:48-09:42) compared with day workers (05:36 hour, 95% CI, 05:06-06:12). Phase delay was stronger among subjects with higher light-at-night exposure and number of nights worked. Night shift workers had lower levels and a delay in peak time of aMT6s production over a 24-hour period. Differences were modified by diurnal preference and intensity of light-at-night exposure. Night shift work affects levels and timing of melatonin production and both parameters may relate to future cancer risk. ©2014 American Association for Cancer Research.

Associations between night work and BMI, alcohol, smoking, caffeine and exercise--a cross-sectional study.

PubMed

Buchvold, Hogne Vikanes; Pallesen, Ståle; Øyane, Nicolas M F; Bjorvatn, Bjørn

2015-11-12

Shift work is associated with negative health effects. Increased prevalence of several cardiovascular risk factors among shift workers/night workers compared with day workers have been shown resulting in increased risk of cardiovascular events among shift workers and night workers. Previous studies have taken a dichotomous approach to the comparison between day and night workers. The present study uses a continuous approach and provides such a new perspective to the negative effects of night work load as a possible risk factor for undesirable health effects. This cross sectional study (The SUrvey of Shift work, Sleep and Health (SUSSH)) uses data collected from December 2008 to March 2009. The study population consists of Norwegian nurses. The study collected information about demographic and lifestyle factors: Body Mass Index (BMI), smoking habits, alcohol consumption, caffeine consumption and exercise habits. The lifestyle parameters were evaluated using multiple hierarchical regression and binary logistic regression. Number of night shifts worked last year (NNL) was used as operationalization of night work load. Adjustment for possible confounders were made. Obesity was defined as BMI > 30. Alcohol Consumption was evaluated using the short form of the Alcohol Use Disorders Identification Test Consumption (AUDIT-C). Data were analyzed using SPSS version 22. We had data from 2059 nurses. NNL was significantly and positively associated with BMI, both when evaluated against BMI as a continuous parameter (Beta = .055, p < .05), and against obesity (OR = 1.01, 95 % CI = 1.00-1.01). The AUDIT-C score was significantly and positively associated with hours worked per week (OR = 1.03, 95 % CI = 1.01-1.05). We found a positive significant association between night work load and BMI. This suggests that workers with a heavy night work load might need special attention and frequent health checks due to higher risk of undesirable health effects.

Sleep Loss, Circadian Mismatch, and Abnormalities in Reorienting of Attention in Night Workers with Shift Work Disorder

PubMed Central

Gumenyuk, Valentina; Howard, Ryan; Roth, Thomas; Korzyukov, Oleg; Drake, Christopher L.

2014-01-01

Study Objectives: Permanent night-shift workers may develop shift-work disorder (SWD). In the current study, we evaluated neurophysiological and behavioral indices of distractibility across times prior to the night shift (T1), during night hours (T2), and after acute sleep deprivation (T3) in permanent hospital night workers with and without SWD. Methods: Ten asymptomatic night workers (NW) and 18 NW with SWD participated in a 25-h sleep deprivation study. Circadian phase was evaluated by dim-light salivary melatonin onset (DLMO). Objective sleepiness was evaluated using the Multiple Sleep Latency Test (MSLT). Electrophysiological distractibility was evaluated by brain event-related potentials (ERP), whereas behavioral distractibility was evaluated by performance on a visual task in an auditory-visual distraction paradigm. Statistical analyses: Comparisons of ERP results were performed by repeated-measures analysis of variance, and t-tests were used where appropriate. A Mann-Whitney U test was used for comparison of variables (MLST, Stanford Sleepiness Scale, and DLMO) that deviated from normal. Results: First, in the SWD group, the reorienting negativity ERP amplitude was significantly attenuated compared to that in the NW group. Second, the SWD group had shorter MSLT during night shift hours (4.8 ± 4.9 min) compared to that in NW (7.8 ± 3.7 min; U = 47; z = -2.1; P < 0.03). Third, NW with SWD had a DLMO at 20:27 ± 5.0 h, whereas healthy NW had a DLMO at 05:00 ± 3.4 h (U = 43.5; z = -2.22, P < 0.03). Finally, acute sleep deprivation impaired behavioral performance and the P3a ERP in both groups. Conclusions: Our results demonstrate specific deficits in neurophysiological activity in the attentional domain among the shift-work disorder group relative to night workers. Citation: Gumenyuk V; Howard R; Roth T; Korzyukov O; Drake CL. Sleep loss, circadian mismatch, and abnormalities in reorienting of attention in night workers with shift work disorder. SLEEP 2014;37(3):545-556. PMID:24587577

Night work and BMI: is it related to on-shift napping?

PubMed

Silva-Costa, Aline; Griep, Rosane Härter; Rotenberg, Lúcia

2017-11-17

On-shift napping can benefit night workers regarding sleep loss, synchronization of circadian rhythms, and alertness. However, few studies on napping can be found in the literature focused on possible health benefits. This cross-sectional study has investigated the role of on-shift napping on the association between night work and BMI in 409 night-shift nursing professionals. The number of working nights and the years of exposure to night work were significantly associated with increased BMI levels among non-nappers, but not among nappers. Results suggest a benefit of napping for weight gain, thus subsidizing occupational health policies on the regulation of on-shift napping among nursing workers.

Night work and BMI: is it related to on-shift napping?

PubMed Central

Silva-Costa, Aline; Griep, Rosane Härter; Rotenberg, Lúcia

2017-01-01

ABSTRACT On-shift napping can benefit night workers regarding sleep loss, synchronization of circadian rhythms, and alertness. However, few studies on napping can be found in the literature focused on possible health benefits. This cross-sectional study has investigated the role of on-shift napping on the association between night work and BMI in 409 night-shift nursing professionals. The number of working nights and the years of exposure to night work were significantly associated with increased BMI levels among non-nappers, but not among nappers. Results suggest a benefit of napping for weight gain, thus subsidizing occupational health policies on the regulation of on-shift napping among nursing workers. PMID:29166450

Night shift work, chronotype and prostate cancer risk in the MCC-Spain case-control study.

PubMed

Papantoniou, Kyriaki; Castaño-Vinyals, Gemma; Espinosa, Ana; Aragonés, Nuria; Pérez-Gómez, Beatriz; Burgos, Javier; Gómez-Acebo, Inés; Llorca, Javier; Peiró, Rosana; Jimenez-Moleón, Jose Juan; Arredondo, Francisco; Tardón, Adonina; Pollan, Marina; Kogevinas, Manolis

2015-09-01

Night shift work has been classified as a probable human carcinogen based on experimental studies and limited human evidence on breast cancer. Evidence on other common cancers, such as prostate cancer, is scarce. Chronotype is an individual characteristic that may relate to night work adaptation. We evaluated night shift work with relation to prostate cancer, taking into account chronotype and disease severity in a population based case-control study in Spain. We included 1,095 prostate cancer cases and 1,388 randomly selected population controls. We collected detailed information on shift schedules (permanent vs. rotating, time schedules, duration, frequency), using lifetime occupational history. Sociodemographic and lifestyle factors were assessed by face-to-face interviews and chronotype through a validated questionnaire. We used unconditional logistic regression analysis adjusting for potential confounders. Subjects who had worked at least for one year in night shift work had a slightly higher prostate cancer risk [Odds Ratio (OR) 1.14; 95%CI 0.94, 1.37] compared with never night workers; this risk increased with longer duration of exposure (≥ 28 years: OR 1.37; 95%CI 1.05, 1.81; p-trend = 0.047). Risks were more pronounced for high risk tumors [D'Amico classification, Relative Risk Ratio (RRR) 1.40; 95%CI 1.05, 1.86], particularly among subjects with longer duration of exposure (≥28 years: RRR 1.63; 95%CI 1.08, 2.45; p-trend = 0.027). Overall risk was higher among subjects with an evening chronotype, but also increased in morning chronotypes after long-term night work. In this large population based study, we found an association between night shift work and prostate cancer particularly for tumors with worse prognosis. © 2014 UICC.

Biological rhythms and rotating shift work : some considerations for air traffic controllers and managers.

DOT National Transportation Integrated Search

1986-01-01

This report is a general review of some of the current themes and practices regarding rotating shift work; to inform air traffic controllers, technicians, and managers of these issues; and to offer some ideas that may be helpful in dealing with diffi...

An Analysis of Workers' Attitudes Toward the 4-Day, 40-Hour Workweek.

ERIC Educational Resources Information Center

Dickinson, Terry L.; Wijting, Jan P.

Employees' attitudes toward a proposed 4-day, 40-hour workweek were examined relative to job and worker variables, expectations about the new workweek schedule, and job-aspect satisfactions. Employees classified by their sex, work shifts, wage schedules, and sex and work shifts differed significantly in their attitudes toward the 4-day, 40-hour…

Dietary habits among persons hired on shift work.

PubMed

Strzemecka, Joanna; Bojar, Iwona; Strzemecka, Ewa; Owoc, Alfred

2014-01-01

Shift-work determinates irregular nutrition habits. The quality as well as the quantity of meals consumed by shift-workers can significantly affects their health. The aim of this study was to evaluate the dietary habits of people performing shift work in the Bogdanka mine. The study was carried out in the Bogdanka mine in Leczna. The questionnaire, which was designed by the author of this dissertation, was conducted among 700 shift-workers, working underground. The results were subjected to statistical analysis based on STATISTICA v. 7.1 (StatSoft, Poland) software. Nearly half of respondents reported regular consumption of meals (40.0%) Interviewees admitted having warm meals during the day (81.4%). The most frequently consumed meal during the day was the hot one (50.9%), three meals and more were consumed the least frequently (8.1%). Almost half of respondents considered their eating habits as inappropriate (46.3%). Among those, nearly half (68.2%) stated that shift - work is the reason for their nutrition habits. More than half of respondents (66.0%) admitted that shift work hampers regular consumption of meals. Shift work makes nourishment and regular consumption difficult. It contributes to the limited amount of warm meals eaten during the day. In order to maintain preventive health care and the improvement of quality of life, shift workers should be provided with an easier access to meals (including warm one) at specified times of the day.

[Fatigue symptoms and workplace related factors of long-term care workers employed in facilities].

PubMed

Kawamura, Sachiyo; Yamada, Kazuko; Morioka, Ikuharu

2015-01-01

"Regular visiting/on-demand response type long-term care" has recently been established. This will lead to a decrease in the burden on the family, but an increase in the burden of the care personnel who provide this kind of long-term care. The objectives of this study were to clarify the fatigue symptoms of long-term care workers in facilities that provide this kind of long-term care, and examine the related factors in the workplace. An anonymous questionnaire survey was conducted with 96 workers engaged in long-term care in facilities. The questionnaire was composed of cumulative fatigue symptoms index, work situation, supports in the workplace, and the attributes. The subjects were divided into two groups: those who had night shift between PM 6 to AM 8 with or without day shift (night shift group), and those who had only day shift (day shift group). The relationships between the fatigue symptom levels and work situation etc. were compared between the two groups. The night shift group consisted of 47 workers, whose mean age was 42.3 years and whose mean working experience was 6.0 years. The median number of persons they had visited in the previous month was 9. The day shift group consisted of 49 workers, whose mean age was 44.6 years and whose mean working experience was 5.9 years. The median number of persons they visited in the previous month was 9.5. Age and sex distributions showed no difference between the two groups. There was no difference in the work situations and the supports in the workplace, except for working time and the details of care the subjects were providing. The fatigue symptom levels were high in both groups, but in the night shift group the level of physical disorders was higher than in the day shift group. Satisfaction with work, education and training for mental health and consideration for traffic safety when making home visits were negatively related to fatigue symptom levels in both groups. Learning care during the previous year, and the ease of receiving paid holiday were not related to the fatigue symptom levels in the night shift group. This was different in the day shift group. Measures of fatigue symptoms should be performed for both groups. It is desirable that supports, additional to that given in the workplace to the day shift group, be given to the night shift group, and its efficacy be researched.

No difference in self reported health among coalminers in two different shift schedules at Spitsbergen, Norway, a two years follow-up.

PubMed

Hanoa, Rolf; Baste, Valborg; Kooij, Arne; Sommervold, Linda; Moen, Bente Elisabeth

2011-01-01

This study was performed among coal miners in the remote location Svea, Spitsbergen. The shift schedule used to be 7 d on and 7 d off. The aim of this study was to investigate possible changes in health after a voluntary implementation of a new shift schedule, with periods of 14 d on and 14 d off, for 74 percent of the workers in 2007. A questionnaire was distributed to all employees before and two times after the new shift schedule, comprising questions on type of work, shift schedule, pain, sleep, stress and coping. Ninety nine percent of the employees responded; 274 in 2006, 307 in 2007 and 312 in 2008. Work neither in the 14/14 shift nor 7/7 shift was related to any change in the health after these two years. The coping index for workers in the 14/14 shift improved.

Klokwerk + study protocol: An observational study to the effects of night-shift work on body weight and infection susceptibility and the mechanisms underlying these health effects.

PubMed

Loef, Bette; van Baarle, Debbie; van der Beek, Allard J; van Kerkhof, Linda W; van de Langenberg, Daniëlla; Proper, Karin I

2016-08-02

Night-shift work may cause severe disturbances in the worker's circadian rhythm, which has been associated with the onset of health problems and diseases. As a substantial part of the workforce is exposed to night-shift work, harmful aspects of night-shift work should not be overlooked. The aim of the Klokwerk + study is to study the effects of night-shift work on body weight and infection susceptibility and the mechanisms underlying these health effects. First, we will study the relation between night-shift work exposure and body weight and between night-shift work exposure and infection susceptibility. Second, we will examine the mechanisms linking night-shift work exposure to body weight and infection susceptibility, with a specific focus on sleep, physical activity, diet, light exposure, vitamin D level, and immunological factors. Lastly, we will focus on the identification of biomarkers for chronic circadian disturbance associated with night-shift work. The design of this study is a prospective observational cohort study consisting of 1,960 health care workers aged 18-65 years. The study population will consist of a group of night-shift workers and an equally sized group of non-night-shift workers. During the study, there will be two measurement periods. As one of the main outcomes of this study is infection susceptibility, the measurement periods will take place at approximately the first (September/October) (T0) and the last month (April/May) (T1, after 6 months) of the flu season. The measurements will consist of questionnaires, anthropometric measurements, a smartphone application to determine infection susceptibility, food diaries, actigraphy, light sensors, and blood sample analyses. The Klokwerk + study will contribute to the current need for high-quality data on the health effects of night-shift work and its underlying behavioral and physiological mechanisms. The findings can be the starting point for the development of interventions that prevent negative health effects caused by night-shift work. In addition, the identification of biomarkers indicative of loss of homeostasis due to circadian disturbance may be an important asset in monitoring the effects of such interventions.

[Health behaviors by job stress level in large-sized company with male and female workers].

PubMed

Park, Hyunju; Jung, Hye-Sun

2010-12-01

This study was done to investigate differences in health behaviors by job stress level in male and female workers in a large-sized company. Participants were 576 male and 228 female workers who completed questionnaires. Job stress was measured using the 'Short Form Korean Occupational Stress Scale (SF-KOSS)'. Health behaviors included smoking, alcohol consumption, regular exercise, and diet. Frequency, mean, SD, chi-square test, and multivariate logistic regression using SAS version 9.1 were used to analyze data. Smoking, drinking and regular exercise rates were not different by job stress level in male or female workers. Only regular diet was significantly different by job stress level in male and female workers. From multivariate analysis, the alcohol consumption rates for female workers differed by marital status. Regular exercise rate was significantly related to age for male workers and type of employment for female workers. After adjusting for demographic and work-related characteristics, regular diet significantly differed by shift work for male workers and marital status and shift work for female workers. The findings of the study indicate that nursing interventions should be developed to manage job stress to improve diet habits for male and female workers in large-sized companies.

Does modifying the timing of meal intake improve cardiovascular risk factors? Protocol of an Australian pilot intervention in night shift workers with abdominal obesity.

PubMed

Bonham, Maxine P; Leung, Gloria K W; Davis, Rochelle; Sletten, Tracey L; Murgia, Chiara; Young, Morag J; Eikelis, Nina; Lambert, Elisabeth A; Huggins, Catherine E

2018-03-14

Shift work is an independent risk factor for cardiovascular disease (CVD). Shift workers who are awake overnight and sleep during the day are misaligned with their body's endogenous circadian rhythm. Eating at night contributes to this increased risk of CVD by forcing the body to actively break down and process nutrients at night. This pilot study aims to determine whether altering meal timing overnight, in a shift working population, will impact favourably on modifiable risk factors for CVD (postprandial bplasma lipids and glucose concentration). A randomised cross-over study with two 4-week test periods, separated by a minimum of a 2-week washout will be undertaken. The effectiveness of redistributing energy intake overnight versus ad libitum eating patterns on CVD risk factors will be examined in night shift workers (n=20), using a standard acute test meal challenge protocol. Primary outcomes (postprandial lipids and glucose) will be compared between the two conditions: post-intervention and post-control period using analysis of variance. Potential effect size estimates to inform sample size calculations for a main trial will also be generated. Ethics approval has been granted by the Monash University Human Research Ethics Committee (2017-8619-10329). Outcomes from this study will determine whether eliminating food intake for a defined period at night (1-6 am) impacts favourably on metabolic risk factors for CVD in night shift workers. Collective results from this novel trial will be disseminated through peer-reviewed journals, and national and international presentations. The results are essential to inform health promotion policies and guidelines for shift workers, especially those who aim to improve their metabolic health. ACTRN12617000791336; Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

[Associations among physical condition, life hour, and dietary intake male Japanese shift workers: physical condition and lifestyle survey of male Japanese shift workers].

PubMed

Fukumura, Tomoe; Yoshita, Katsushi; Tabata, Masaji

2015-01-01

The purpose of this study was to understand the actual state of life hours (working time, sleep time, and time of meal intake) and dietary habits of male shift work employees, and to elucidate the impact of working arrangements and dietary habits on their physical condition and health problems. The subjects were 187 male employees (aged 18-64 years) working for an industrial company in Toyama prefecture. We used a self-administered questionnaire to assess dietary habit, lifestyle habits, and life hours at the time of a periodic health examination in April 2013. The subjects were grouped based on their working condition (i.e., day shift, late shift, and late-night shift) into two groups of day shift (n = 107) and shiftwork (n = 80). The proportion of time spent sleeping and feeding was determined in half hour increments, and the incidences of skipping meals (breakfast, lunch and dinner) and midnight snack intake were calculated for each working condition. We also examined the association between the frequency of eating and physical condition for each working condition. The state of life hours of the shiftwork group during the day was similar to that of the day shift group. However, the workers' state of life hours, incidences of skipping meals, and midnight snack intake varied considerably when working at the other shift times. In the shiftwork group, regardless of the working patterns, the BMI and % body fat of the group that ate more than three times a day were significantly lower than those of the group that ate less than twice a day. The results of the present study suggest that it is difficult to ensure the time and opportunity for meals for shift workers. We consider that it is necessary to prevent them skipping of meals, and to support a proper dietary intake during the night.

The role of human-at-work systems in business sustainability: perspectives based on expert and qualified production workers in a manufacturing enterprise.

PubMed

Genaidy, Ash M; Rinder, Maria M; Sequeira, Reynold; A-Rehim, Amal

2010-04-01

A community of highly qualified employees is desirable for the workforce to become a competitive business advantage, improving and sustaining corporate health. Currently, the scientific literature is limited on information comparing the assessment of expert and qualified workers for the employee-work environment interface. Such information would be valuable for industrial managers to obtain and act on the different perspectives of its workers for business improvement and survivability. A primary objective of this study is to explore the perspectives of expert and qualified workers on the quality of the employee-work environment interface in a manufacturing enterprise. This investigation was performed in a production department in a small manufacturing enterprise. Two expert workers participated in the study, with each being in the company for 30 years and having performed all jobs in the production department as well as supervisory and line management responsibilities. A total of 13 qualified workers from day and night shifts were used in the study, with the great majority of workers possessing 10 or more years of on-the-job experience but not acquiring the same specialised knowledge required for operating the technological resources in the department. The work compatibility methodology was used to assess the quality of employee-work environment interface for both expert and qualified workers. Both expert and qualified workers provided similar trends in terms of their compatibility assessment of experienced and acting work domains. In general, the compatibility levels for the day shift were poorer than those obtained for the night shift for acting work domains. The similarities in assessment between the expert and qualified workers were much closer for factors impacting job performance at the task and immediate surrounding levels (i.e. physical and mental task content, physical environment). There were greater differences at the macro level, that is, at the process and enterprise levels, in terms of organisational/social/technological environment. This is particularly noted for the organisational environment. The compatibility values obtained for the experienced domains mirror those obtained for acting domains. The overall workload was assessed as requiring major redesign during the day shift and needing added responsibilities for the night shift according to both expert and qualified workers. The assessment of qualified workers is comparable with that of expert workers for the job content and immediate surroundings. Differences are more observed for process- and enterprise-based factors; thereby, providing company management different perspectives in order to devise organisational strategies conducive for optimum human and corporate health and pointing to the probable interactions of the different systems impacting individual and enterprise performance. STATEMENT OF RELEVANCE: This research examines similarities and differences between qualified and expert workers in their assessment of the worker-work environment interface. The contribution to improved understanding of the complex interactions of human-at-work and enterprise systems should be beneficial to organisations in their quest to remain competitive in a global economy.

Invisible Electronic States and Their Dynamics Revealed by Perturbations

NASA Astrophysics Data System (ADS)

Merer, Anthony J.

2011-06-01

Sooner or later everyone working in the field of spectroscopy encounters perturbations. These can range in size from a small shift of a single rotational level to total destruction of the vibrational and rotational patterns of an electronic state. To some workers perturbations are a source of terror, but to others they are the most fascinating features of molecular spectra, because they give information about molecular dynamics, and about states that would otherwise be invisible as a result of unfavorable selection rules. An example of the latter is the essentially complete characterization of the tilde{b}^3A_2 state of SO_2 from the vibronic perturbations it causes in the tilde{a}^3B_1 state. The S_1-trans state of acetylene is a beautiful example of dynamics in action. The level patterns of the three bending vibrations change dramatically with increasing vibrational excitation as a result of the vibrational angular momentum and the approach to the isomerization barrier. Several vibrational levels of the S_1-cis isomer, previously thought to be unobservable, can now be assigned. They obtain their intensity through interactions with nearby levels of the trans isomer.

Factors associated with severe occupational injuries at mining company in Zimbabwe, 2010: a cross-sectional study

PubMed Central

Chimamise, Chipo; Gombe, Notion Tafara; Tshimanga, Mufuta; Chadambuka, Addmore; Shambira, Gerald; Chimusoro, Anderson

2013-01-01

Introduction Injury rate among mining workers in Zimbabwe was 789/1000 workers in 2008. The proportion of severe occupational injuries increased from 18% in 2008 to 37% in 2009. We investigated factors associated with severe injuries at the mine. Methods An unmatched 1:1 case-control study was carried out at the mine, a case was any worker who suffered severe occupational injury at the mine and was treated at the mine or district hospital from January 2008 to April 2010, a control was any worker who did not suffer occupational injury during same period. We randomly selected 156 cases and 156 controls and used interviewer administered questionnaires to collect data from participants. Results Majority of cases, 155(99.4%) and of controls 142(91%) were male, 127(81.4%) of cases and 48(30.8%) of controls worked underground. Majority (73.1%) of severe occupational injuries occurred during night shift. Underground temperatures reached 500C. Factors independently associated with getting severe occupational injuries included working underground (AOR = 10.55; CI 5.97-18.65), having targets per shift (AOR = 12.60; CI 3.46-45.84), inadequate PPE (AOR= 3.65 CI 1.34-9.89) and working more than 8 hours per shift (AOR = 8.65 CI 2.99-25.02). Conclusion Having targets exerts pressure to perform on workers. Prolonged working periods decrease workers’ attention and concentration resulting in increased risk to severe injuries as workers become exhausted, lose focus and alertness. Underground work environment had environmental hazards so managers to install adequate ventilation and provide adequate PPE. Management agreed to standardize shifts to eight hours and workers in some departments have been supplied with adequate PPE. PMID:23504270

A Pilot Study to Examine the Relationship Between Napping and Fatigue in Nurses Practicing on the Night Shift.

PubMed

Neville, Kathleen; Velmer, Gillian; Brown, Shari; Robol, Nancy

2017-11-01

The aim of this study is to explore the relationship of night-shift napping on fatigue. Nurses' fatigue, especially at night, interferes with quality of life and job performance and impacts safety and health. Night-shift nurses completed the Brief Fatigue Inventory and a demographic information sheet to determine differences in fatigue between nurses who napped during their night shift as compared with nurses who did not nap. No statistically significant differences in global fatigue were found; differences in rotating shift, age, and, gender were identified. Rotating shifts, a 2nd job, and caring for family predicted fatigue. Based on this pilot study, further investigations of fatigue among night-shift nurses are needed as well as evidence-based support to promote sleep.

Anomalous center of mass shift: gravitational dipole moment.

NASA Astrophysics Data System (ADS)

Jeong, Eue Jin

1997-02-01

The anomalous, energy dependent shift of the center of mass of an idealized, perfectly rigid, uniformly rotating hemispherical shell which is caused by the relativistic mass increase effect is investigated in detail. It is shown that a classical object on impact which has the harmonic binding force between the adjacent constituent particles has the similar effect of the energy dependent, anomalous shift of the center of mass. From these observations, the general mode of the linear acceleration is suggested to be caused by the anomalous center of mass shift whether it's due to classical or relativistic origin. The effect of the energy dependent center of mass shift perpendicular to the plane of rotation of a rotating hemisphere appears as the non zero gravitational dipole moment in general relativity. Controlled experiment for the measurement of the gravitational dipole field and its possible links to the cylindrical type line formation of a worm hole in the extreme case are suggested. The jets from the black hole accretion disc and the observed anomalous red shift from far away galaxies are considered to be the consequences of the two different aspects of the dipole gravity.

Sleep and autonomic nervous system changes - enhanced cardiac sympathetic modulations during sleep in permanent night shift nurses.

PubMed

Chung, Min-Huey; Kuo, Terry B J; Hsu, Nanly; Chu, Hsin; Chou, Kuei-Ru; Yang, Cheryl C H

2009-05-01

Disturbed sleep is the most common problem among the many health-related effects of shift work, with shift workers clearly having higher rates of cardiac disorders. However, the possible mechanism underlying the related health effects of shift work has yet to be examined. Consequently, this study aimed to explore the influence of long-term night shift work on the sleep patterns of nurses and their cardiac autonomic nervous system during sleep. Our sample comprised ten permanent night shift and ten regular morning shift nurses. Nurses slept in their dormitory where they were allowed to sleep and wake spontaneously. All sleep parameters were digitized using an ambulatory polysomnographic recorder. Using sleep patterns and heart rate variability, the day- and nighttime sleep of permanent night shift nurses were compared with the nighttime sleep of regular morning shift nurses. Compared with the nighttime sleep of regular morning shift nurses, the pattern of daytime sleep of permanent night shift nurses showed significantly lower sleep onset latency. Permanent night shift nurses' daytime sleep also had greater proportions of Stage 3 and 4 (deep sleep), and arousal index than recorded during their nighttime sleep. Both the low frequency and low to high frequency ratio of the nighttime sleep of night shift nurses were significantly higher during periods of non-rapid eye movement (NREM) sleep than the nighttime sleep of morning shift workers. In addition, the electroencephalography delta-power of the nighttime sleep of night shift nurses was significantly lower during the first NREM episode sleep than those of both the daytime sleep of night shift workers and the nighttime sleep of morning shift nurses. Permanent night shift nurses have higher sympathetic activity during nighttime sleep than regular morning shift nurses. Night shift working may have effects on the sleeping patterns of nurses in the long run, inducing higher cardiac sympathetic regulation.

Predictive factors of life quality among packaging workers in Taiwan.

PubMed

Yang, Shang-Yu; Hsu, Der-Jen; Yen, Chun-Ming; Chang, Jer-Hao

2018-05-16

The semiconductor plants on the top of high-tech industrial chain hire many packaging workers to carry out miscellaneous packing tasks for various product orders from different companies and countries. Under tremendous workload the quality of life (QoL) of such packaging workers need to be concerned. The aim of this study was to explore factors influencing their QoL. This study recruited 247 packing workers (162 male and 85 female; mean age: 35.6 years old) in 2015 and 2016 from a semiconductor plant in Taiwan by convenience sampling. The questionnaire comprised four parts: demographics, the World Health Organization Quality of Life (WHOQOL-BREF), an occupational burnout inventory and the Nordic Musculoskeletal Questionnaire. The four domains of the WHOQOL-BREF were defined as outcome variables. Predictive factors included gender (reference: male), age (reference: ≤ 35), BMI (reference: ≤ 25), educational level (reference: below university), marital/partner status (reference: married/cohabiting), years of work (reference: ≤ 5), work shift (reference: day shift), personal burnout, work-related burnout, over-commitment to work and the number of body parts with discomfort (0-9). The findings showed that physical QoL was negatively correlated with night -shift work, personal burnout, and number of body parts with discomfort. Psychological QoL was negatively correlated with night shift work and personal burnout. Environment QoL was negatively correlated with being male, night shift work and personal burnout. The results showed that the QoL among the packaging workers could be improved by reducing musculoskeletal discomfort, personal burnout and by improving work schedules.

Effects of napping on sleepiness and sleep-related performance deficits in night-shift workers: a systematic review.

PubMed

Ruggiero, Jeanne S; Redeker, Nancy S

2014-04-01

Night-shift workers are prone to sleep deprivation, misalignment of circadian rhythms, and subsequent sleepiness and sleep-related performance deficits. The purpose of this narrative systematic review is to critically review and synthesize the scientific literature regarding improvements in sleepiness and sleep-related performance deficits following planned naps taken during work-shift hours by night workers and to recommend directions for future research and practice. We conducted a literature search using the Medline, PsychInfo, CINAHL, Cochrane Library, and Health and Safety Science Abstracts databases and included English-language quasi-experimental and experimental studies that evaluated the effects of a nighttime nap taken during a simulated or actual night-work shift. We identified 13 relevant studies, which consisted primarily of small samples and mixed designs. Most investigators found that, despite short periods of sleep inertia immediately following naps, night-shift napping led to decreased sleepiness and improved sleep-related performance. None of the studies examined the effects of naps on safety outcomes in the workplace. Larger-scale randomized clinical trials of night-shift napping and direct safety outcomes are needed prior to wider implementation.

The influence of shift work on cognitive functions and oxidative stress.

PubMed

Özdemir, Pınar Güzel; Selvi, Yavuz; Özkol, Halil; Aydın, Adem; Tülüce, Yasin; Boysan, Murat; Beşiroğlu, Lütfullah

2013-12-30

Shift work influences health, performance, activity, and social relationships, and it causes impairment in cognitive functions. In this study, we investigated the effects of shift work on participants' cognitive functions in terms of memory, attention, and learning, and we measured the effects on oxidative stress. Additionally, we investigated whether there were significant relationships between cognitive functions and whole blood oxidant/antioxidant status of participants. A total of 90 health care workers participated in the study, of whom 45 subjects were night-shift workers. Neuropsychological tests were administered to the participants to assess cognitive function, and blood samples were taken to detect total antioxidant capacity and total oxidant status at 08:00. Differences in anxiety, depression, and chronotype characteristics between shift work groups were not significant. Shift workers achieved significantly lower scores on verbal memory, attention-concentration, and the digit span forward sub-scales of the Wechsler Memory Scale-Revised (WMS-R), as well as on the immediate memory and total learning sub-scales of the Auditory Verbal Learning Test (AVLT). Oxidative stress parameters were significantly associated with some types of cognitive function, including attention-concentration, recognition, and long-term memory. These findings suggest that night shift work may result in significantly poorer cognitive performance, particularly working memory. © 2013 Elsevier Ireland Ltd. All rights reserved.

The effectiveness of job rotation to prevent work-related musculoskeletal disorders: protocol of a cluster randomized clinical trial.

PubMed

Comper, Maria Luiza Caires; Padula, Rosimeire Simprini

2014-05-22

Job rotation has often been used in situations where the level of exposure cannot be reduced due to the characteristics of the job or through physical measures. However, the effectiveness of the job rotation strategy at preventing musculoskeletal complaints lacks adequate scientific data. A cluster randomized controlled trial will be used to investigate the effectiveness of job rotation to prevent musculoskeletal disorders in industrial workers. The randomized cluster was based in characteristics of production sectors. A total cluster will be 4 sectors, and 957 workers will be recruited from a textile industry and randomly allocated into intervention or control groups. Both groups will receive training on ergonomics guidelines. In addition, the intervention group will perform job rotation, switching between tasks with low, moderate, and high risk for musculoskeletal complaints. The primary outcome will be the number of working hours lost due to sick leave by musculoskeletal injuries recorded in employee administrative data bases. Secondary outcomes measured via survey include: body parts with musculoskeletal pain, the intensity of this pain, physical workload, fatigue, general health status, physical activity level, and work productivity. Secondary outcome measures will be assessed at baseline and after 3, 6, 9, and 12 months. The cost-effectiveness analysis will be performed from the societal and company perspective. Prevention of work-related musculoskeletal disorders is beneficial for workers, employers, and society. The results of this study will provide new information about the effectiveness of job rotation as a strategy to reduce work-related musculoskeletal disorders. NCT01979731, November 3, 2013.

The effectiveness of job rotation to prevent work-related musculoskeletal disorders: protocol of a cluster randomized clinical trial

PubMed Central

2014-01-01

Background Job rotation has often been used in situations where the level of exposure cannot be reduced due to the characteristics of the job or through physical measures. However, the effectiveness of the job rotation strategy at preventing musculoskeletal complaints lacks adequate scientific data. Methods/Design A cluster randomized controlled trial will be used to investigate the effectiveness of job rotation to prevent musculoskeletal disorders in industrial workers. The randomized cluster was based in characteristics of production sectors. A total cluster will be 4 sectors, and 957 workers will be recruited from a textile industry and randomly allocated into intervention or control groups. Both groups will receive training on ergonomics guidelines. In addition, the intervention group will perform job rotation, switching between tasks with low, moderate, and high risk for musculoskeletal complaints. The primary outcome will be the number of working hours lost due to sick leave by musculoskeletal injuries recorded in employee administrative data bases. Secondary outcomes measured via survey include: body parts with musculoskeletal pain, the intensity of this pain, physical workload, fatigue, general health status, physical activity level, and work productivity. Secondary outcome measures will be assessed at baseline and after 3, 6, 9, and 12 months. The cost-effectiveness analysis will be performed from the societal and company perspective. Discussion Prevention of work-related musculoskeletal disorders is beneficial for workers, employers, and society. The results of this study will provide new information about the effectiveness of job rotation as a strategy to reduce work-related musculoskeletal disorders. Trial registration NCT01979731, November 3, 2013 PMID:24885958

Offshore fleet workers and the circadian adaptation of core body temperature, blood pressure and heart rate to 12-h shifts: a field study.

PubMed

Hansen, Jakob Hønborg; Geving, Ingunn Holmen; Reinertsen, Randi Eidsmo

2010-01-01

The aim of this study was to investigate the circadian adaptation of tcr (core body temperature), BP (blood pressure), HR (heart rate) and subjective sleep quality after 7 days of working 12-h night shifts in offshore fleet workers. Night workers (N = 7) (18:00-6:00) and day workers (N = 7) (6:00-18:00) were recruited from a Norwegian offshore company operating in the North Sea. We measured t(cr), BP and HR on days 1 and 7. An increase of 0.6 °C (p = .03) was observed within the group of night workers from day 1 to day 7. Between the night and day workers there was a significant difference of 0.6 °C from day 1 to day 7 (p = .01). Sleep latency and sleep length also showed significant differences between the groups (p = .01 and p = .04). There was an interaction effect in tiredness during the shift (p = .02). The significant increase in tcr indicates an adaptation in the night workers to the new working schedule, and the extended working hours and sleep deprivation are hypothesized to be the main cause of the increased t(cr). Light exposure, altered pattern of food availability and physical activity are likely to have contributed as well. Subjective sleep quality showed inconclusive results.

Occupational Exposure to Polycyclic Aromatic Hydrocarbons in Polish Coke Plant Workers.

PubMed

Zając, Joanna; Gomółka, Ewa; Maziarz, Barbara; Szot, Wojciech

2016-11-01

Assessment of occupational exposure to polycyclic aromatic hydrocarbons (PAHs) is an urgent and important task to prevent workers' illnesses. 1-Hydroxypyrene is one of the most commonly used biomarkers. The presented study assessed exposure to PAHs molecules among 619 individuals, men working in coke plant. Average number of years spent on working posts in exposition to PAHs was 31.5 years with standard deviation = 5.3. About 35% were smokers with 14.7 cigarettes per day. For each individual, 1-hydroxypyrene concentration in urine samples was measured. Urine 1-hydroxypyrene concentration correlated with air PAHs concentration. Difference between smokers and non-smokers was statistically significant. The median value for post-shift samples was 1.3 µg g -1 and for pre-shift sample concentration reached 0.3 µg g -1 Maximal assessed concentration was 7.6 µg g -1 among pre-shift samples and 27.8 µg g -1 among post-shift samples. The most exposed working posts were coke oven workers and coal derivatives production workers. Results obtained in presented study are relatively low in comparison to other countries or other Polish results but for further improvement a regular measurement of any PAHs' biomarker should be included to standard periodic health examinations for coke plant workers. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Dynamical manifestation of an evolving Berry phase as a frequency shift of the resonance transition between two eigenstates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toriyama, Koichi; Oguchi, Akihide; Morinaga, Atsuo

2011-12-15

We investigate the phenomenon that a Berry phase evolving linearly in time induces a frequency shift of the resonance transition between two eigenstates, regardless of whether or not they are superposed. Using the magnetic-field-insensitive two-photon microwave--radio-frequency transition, which is free of any other dynamical frequency shift, we demonstrate that the frequency shift caused by a uniform rotation of the magnetic field corresponds to the derivative of the Berry phase with respect to time and depends on the direction of rotation of the magnetic field.

Mental health and well-being concerns of fly-in fly-out workers and their partners in Australia: a qualitative study

PubMed Central

Vandelanotte, Corneel

2018-01-01

Objectives Fly-in fly-out (FIFO) work involves commuting long distances to the worksite and living in provided accommodation for 1–4 weeks while on shift. While the potentially detrimental impact of FIFO work on the health and well-being of workers has been documented, little attention has been paid to how workers, or their partners, cope with this impact. This study sought to investigate how workers and their partners negotiate the impact of FIFO on their mental health and well-being. Design The study design was qualitative. FIFO workers and partners responded to open-ended questions on concerns about the FIFO lifestyle and the support they use. Setting Australian FIFO workers and partners responded to the questions via email. Participants Participants were 34 FIFO workers (25 men, M age=41 years) and 26 partners of FIFO workers (26 women, M age=40 years). Results Participant-validated thematic analysis generated three main themes: managing multiple roles, impact on mental health and well-being, and social support needs. Results revealed difficulties in adjusting between the responsibilities of perceptually distinct on-shift and off-shift lives, and managing potential psychological distance that develops while workers are on site. Participants emphasised the importance of maintaining quality communication and support from family members. Workers and partners attempted to maintain mental health and well-being by regularly engaging with support networks, although many felt organisational support was tokenistic, stigmatised or lacking. Conclusions Recommendations for enhancing support provided by FIFO organisations are offered. In particular, organisations should emphasise the importance of good mental health and well-being, maintain transparency regarding potential challenges of FIFO lifestyles, and offer professional support for managing multiple social roles and effective communication. PMID:29519796

Influence of night-shift and napping at work on urinary melatonin, 17-β-estradiol and clock gene expression in pre-menopausal nurses.

PubMed

Bracci, M; Copertaro, A; Manzella, N; Staffolani, S; Strafella, E; Nocchi, L; Barbaresi, M; Copertaro, B; Rapisarda, V; Valentino, M; Santarelli, L

2013-01-01

Night-workers experience disruption of the sleep-wake cycle and light at night which may increase breast cancer risk by suppressing the nocturnal melatonin surge, resulting in higher levels of circulating estrogens. Night-work may also deregulate peripheral clock genes which have been found to be altered in breast cancer. This study investigated urinary 6-sulfatoxymelatonin (aMT6s), serum 17-beta-estradiol levels in premenopausal shift nurses at the end of the night-shift compared to a control group of daytime nurses. Peripheral clock gene expression in lymphocytes were also investigated. All participants were sampled in the follicular phase of the menstrual cycle. The effect of nurses’ ability to take a short nap during the night-shift was also explored. The shift-work group had significantly lower aMT6s levels than daytime nurses independently of a nap. Night-shift napping significantly influences 17-beta-estradiol levels resulting in higher outcomes in nurses who do not take a nap compared to napping group and daytime workers. Peripheral clock genes expression investigated was not significantly different among the groups. Our findings suggest that shift nurses experience changes in aMT6s levels after a night-shift. Napping habits influence 17-beta-estradiol levels at the end of a night-shift. These findings might be related to the increased cancer risk reported in night-shift workers and suggest that a short nap during night-shifts may exert a positive effect.

Properties of solar ephemeral regions at the emergence stage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Shuhong; Zhang, Jun, E-mail: shuhongyang@nao.cas.cn, E-mail: zjun@nao.cas.cn

2014-01-20

For the first time, we statistically study the properties of ephemeral regions (ERs) and quantitatively determine their parameters at the emergence stage based on a sample of 2988 ERs observed by the Solar Dynamics Observatory. During the emergence process, there are three kinds of kinematic performances, i.e., separation of dipolar patches, shift of the ER's magnetic centroid, and rotation of the ER's axis. The average emergence duration, flux emergence rate, separation velocity, shift velocity, and angular speed are 49.3 minutes, 2.6 × 10{sup 15} Mx s{sup –1}, 1.1 km s{sup –1}, 0.9 km s{sup –1}, and 0.°6 minute{sup –1}, respectively.more » At the end of emergence, the mean magnetic flux, separation distance, shift distance, and rotation angle are 9.3 × 10{sup 18} Mx, 4.7 Mm, 1.1 Mm, and 12.°9, respectively. We also find that the higher the ER magnetic flux is, (1) the longer the emergence lasts, (2) the higher the flux emergence rate is, (3) the further the two polarities separate, (4) the lower the separation velocity is, (5) the larger the shift distance is, (6) the slower the ER shifts, and (7) the lower the rotation speed is. However, the rotation angle seems not to depend on the magnetic flux. Not only at the start time, but also at the end time, the ERs are randomly oriented in both the northern and the southern hemispheres. Finally, neither the anti-clockwise-rotated ERs nor the clockwise rotated ones dominate the northern or the southern hemisphere.« less

The association between weekly work hours, crew familiarity, and occupational injury and illness in emergency medical services workers.

PubMed

Weaver, Matthew D; Patterson, P Daniel; Fabio, Anthony; Moore, Charity G; Freiberg, Matthew S; Songer, Thomas J

2015-12-01

Emergency Medical Services (EMS) workers are shift workers in a high-risk, uncontrolled occupational environment. EMS-worker fatigue has been associated with self-reported injury, but the influence of extended weekly work hours is unknown. A retrospective cohort study was designed using historical shift schedules and occupational injury and illness reports. Using multilevel models, we examined the association between weekly work hours, crew familiarity, and injury or illness. In total, 966,082 shifts and 950 reports across 14 EMS agencies were obtained over a 1-3 year period. Weekly work hours were not associated with occupational injury or illness. Schedule characteristics that yield decreased exposure to occupational hazards, such as part-time work and night work, conferred reduced risk of injury or illness. Extended weekly work hours were not associated with occupational injury or illness. Future work should focus on transient exposures and agency-level characteristics that may contribute to adverse work events. © 2015 Wiley Periodicals, Inc.

Shift work and work injury in the New Zealand Blood Donors' Health Study.

PubMed

Fransen, M; Wilsmore, B; Winstanley, J; Woodward, M; Grunstein, R; Ameratunga, S; Norton, R

2006-05-01

To investigate associations between work patterns and the occurrence of work injury. A cross sectional analysis of the New Zealand Blood Donors Health Study conducted among the 15 687 (70%) participants who reported being in paid employment. After measurement of height and weight, a self-administered questionnaire collected information concerning occupation and work pattern, lifestyle behaviour, sleep, and the occurrence of an injury at work requiring treatment from a doctor during the past 12 months. Among paid employees providing information on work pattern, 3119 (21.2%) reported doing shift work (rotating with nights, rotating without nights, or permanent nights) and 1282 (8.7%) sustained a work injury. In unadjusted analysis, work injury was most strongly associated with employment in heavy manual occupations (3.6, 2.8 to 4.6) (relative risk, 95% CI), being male (1.9, 1.7 to 2.2), being obese (1.7, 1.5 to 2.0), working rotating shifts with nights (2.1, 1.7 to 2.5), and working more than three nights a week (1.9, 1.6 to 2.3). Snoring, apnoea or choking during sleep, sleep complaints, and excessive daytime sleepiness were also significantly associated with work injury. When mutually adjusting for all significant risk factors, rotating shift work, with or without nights, remained significantly associated with work injury (1.9, 1.5 to 2.4) and (1.8, 1.2 to 2.6), respectively. Working permanent night shifts was no longer significantly associated with work injury in the adjusted model. Work injury is highly associated with rotating shift work, even when accounting for increased exposure to high risk occupations, lifestyle factors, and excessive daytime sleepiness.

78 FR 37586 - TE Connectivity, CIS-Appliances Division, Including On-Site Leased Workers From Kelly Services...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-21

... supply of administrative support services (in support of production). The worker group includes on-site... components produced by the subject workers. Further, aggregate imports of articles like or directly... reconsideration, the worker supplied new information regarding a possible shift in the production of like or...

Air, hand wipe, and surface wipe sampling for Bisphenol A (BPA) among workers in industries that manufacture and use BPA in the United States.

PubMed

Hines, Cynthia J; Jackson, Matthew V; Christianson, Annette L; Clark, John C; Arnold, James E; Pretty, Jack R; Deddens, James A

2017-11-01

For decades, bisphenol A (BPA) has been used in making polycarbonate, epoxy, and phenolic resins and certain investment casting waxes, yet published exposure data are lacking for U.S. manufacturing workers. In 2013-2014, BPA air and hand exposures were quantified for 78 workers at six U.S. companies making BPA or BPA-based products. Exposure measures included an inhalable-fraction personal air sample on each of two consecutive work days (n = 146), pre- and end-shift hand wipe samples on the second day (n = 74 each), and surface wipe samples (n = 88). Potential determinants of BPA air and end-shift hand exposures (after natural log transformation) were assessed in univariate and multiple regression mixed models. The geometric mean (GM) BPA air concentration was 4.0 µg/m 3 (maximum 920 µg/m 3 ). The end-shift GM BPA hand level (26 µg/sample) was 10-times higher than the pre-shift level (2.6 µg/sample). BPA air and hand exposures differed significantly by industry and job. BPA air concentrations and end-shift hand levels were highest in the BPA-filled wax manufacturing/reclaim industry (GM Air = 48 µg/m 3 , GM Hand-End = 130 µg/sample) and in the job of working with molten BPA-filled wax (GM Air = 43 µg/m 3 , GM Hand-End = 180 µg/sample), and lowest in the phenolic resins industry (GM Air = 0.85 µg/m 3 , GM Hand-End = 0.43 µg/sample) and in the job of flaking phenolic resins (GM AIR = 0.62 µg/m 3 , GM Hand-End = 0.38 µg/sample). Determinants of increased BPA air concentration were industry, handling BPA containers, spilling BPA, and spending ≥50% of the shift in production areas; increasing age was associated with lower air concentrations. BPA hand exposure determinants were influenced by high values for two workers; for all other workers, tasks involving contact with BPA-containing materials and spending ≥50% of the shift in production areas were associated with increased BPA hand levels. Surface wipe BPA levels were significantly lower in eating/office areas (GM = 9.3 µg/100 cm 2 ) than in production areas (GM = 140 µg/100 cm 2 ). In conclusion, worker BPA exposure was associated with tasks and conditions affecting both inhalation and dermal exposure. The potential for BPA-related health effects among these workers is unknown.

Rotating night shifts too quickly may cause anxiety and decreased attentional performance, and impact prolactin levels during the subsequent day: a case control study.

PubMed

Chang, Yu-San; Chen, Hsiang-Lan; Wu, Yu-Hsuan; Hsu, Chung-Yao; Liu, Ching-Kuan; Hsu, Chin

2014-08-05

We investigated circadian changes and effects on mood, sleep-related hormones and cognitive performance when nurses worked consecutive night shifts in a rapidly rotating shift system. Daytime cognitive function, sleep propensity and sleep-related hormones (growth hormone, cortisol, prolactin, thyrotropin) were compared after participants worked two and four consecutive night shifts. Twenty-three off-duty nurses, 20 nurses working two consecutive night shifts and 16 nurses working four consecutive night shifts were enrolled. All participants completed the Maintenance of Wakefulness Test, State-Trait Anxiety Inventory, Stanford Sleepiness Scale, visual attention tasks (VAT), Wisconsin Card Sorting Test, and modified Multiple Sleep Latency Test. Hormone levels were also measured four times throughout the day, at 2-h intervals. During the day, the participants in the night shift groups were less able to maintain wakefulness, had poor performance on VAT, and higher thyrotropin levels than did those in the off-duty group. Participants who worked two night shifts were better able to maintain wakefulness, had higher anxiety scale scores, poorer initial performance and lack of learning effect on VAT, and higher prolactin levels compared with those who worked four night shifts. There were no differences in cortisol levels between the two- and four- shift groups. Rotating night shifts too quickly may cause anxiety and decreased attentional performance, and may impact daytime prolactin levels after night shifts. It is possible that the two-shift group had a higher cortisol level than did the four-shift group, which would be consistent with the group's higher state anxiety scores. The negative findings may be due to the small sample size. Further studies on the effects of consecutive night shifts on mood and cortisol levels during the daytime after sleep restriction would be valuable.

Organisational characteristics associated with shift work practices and potential opportunities for intervention: findings from a Canadian study.

PubMed

Hall, Amy L; Smit, Andrea N; Mistlberger, Ralph E; Landry, Glenn J; Koehoorn, Mieke

2017-01-01

Shift work is a common working arrangement with wide-ranging implications for worker health. Organisational determinants of shift work practices are not well characterised; such information could be used to guide evidence-based research and best practices to mitigate shift work's negative effects. This exploratory study aimed to describe and assess organisational-level determinants of shift work practices thought to affect health, across a range of industry sectors. Data on organisational characteristics, shift work scheduling, provision of shift work education materials/training to employees and night-time lighting policies in the workplace were collected during phone interviews with organisations across the Canadian province of British Columbia. Relationships between organisational characteristics and shift work practices were assessed using multivariable logistic regression models. The study sample included 88 participating organisations, representing 30 700 shift workers. Long-duration shifts, provision of shift work education materials/training to employees and night-time lighting policies were reported by approximately one-third of participating organisations. Odds of long-duration shifts increased in larger workplaces and by industry. Odds of providing shift work education materials/training increased in larger workplaces, in organisations reporting concern for shift worker health and in organisations without seasonal changes in shift work. Odds of night-time lighting policies in the workplace increased in organisations reporting previous workplace accidents or incidents that occurred during non-daytime hours, site maintenance needs and client service or care needs. This study points to organisational determinants of shift work practices that could be useful for targeting research and workplace interventions. Results should be interpreted as preliminary in an emerging body of literature on shift work and health. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Associations Among Rotating Night Shift Work, Sleep, and Skin Cancer in Nurses’ Health Study II Participants

PubMed Central

Heckman, Carolyn J.; Kloss, Jacqueline D.; Feskanich, Diane; Culnan, Elizabeth; Schernhammer, Eva S.

2016-01-01

Background Night shift work and sleep duration have been associated with breast and other cancers. Results from the few prior studies of night shift work and skin cancer risk have been mixed and not fully accounted for other potentially important health-related variables (e.g., sleep characteristics). This study evaluated the relationship between rotating night shift work and skin cancer risk and included additional skin cancer risk factors and sleep-related variables. Methods The current study used data from 74,323 Nurses’ Health Study (NHS) II participants. Cox proportional hazards models were used to estimate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for skin cancers across categories of shift work and sleep duration. Results Over 10 years of follow-up, 4308 BCC, 334 SCC and 212 melanoma cases were identified. Longer duration of rotating night shifts was associated with a linear decline in risk of BCC (HR=0.93, 95% CI: 0.90-0.97 per 5-year increase). Shift work was not significantly associated with either melanoma (HR=1.02, 95% CI: 0.86-1.21) or SCC (HR=0.92, 95% CI: 0.80-1.06). A short sleep duration (≤6 hours per day) was associated with lower risks of melanoma (HR=0.68, 95% CI: 0.46-0.98) and BCC (HR=0.93, 95% CI: 0.86-1.00) compared with the most common report of 7 hours. SCC was not associated with duration of sleep (HR=0.94, 95% CI: 0.83-1.06). Conclusions Longer duration of rotating night shift work and shorter sleep duration were associated with lower risk of some skin cancers. Further research is needed to confirm and identify the mechanisms underlying these associations. PMID:27663986

Physiological, biochemical, and psychological responses in air traffic control personnel : comparison of the 5-day and 2-2-1 shift rotation patterns.

DOT National Transportation Integrated Search

1973-12-01

Stress in controllers on the straight five-day shift was determined at Houston Intercontinental Tower in 1970. In 1971 controllers on the 2-2-1 rotation were studied at the same tower. Controllers generally prefer the 2-2-1 to the straight five-day s...

Using Doppler Shifts of GPS Signals To Measure Angular Speed

NASA Technical Reports Server (NTRS)

Campbell, Charles E., Jr.

2006-01-01

A method has been proposed for extracting information on the rate of rotation of an aircraft, spacecraft, or other body from differential Doppler shifts of Global Positioning System (GPS) signals received by antennas mounted on the body. In principle, the method should be capable of yielding low-noise estimates of rates of rotation. The method could eliminate the need for gyroscopes to measure rates of rotation. The method is based on the fact that for a given signal of frequency ft transmitted by a given GPS satellite, the differential Doppler shift is attributable to the difference between those components of the instantaneous translational velocities of the antennas that lie along the line of sight from the antennas to the GPS satellite.

Preparation of Single-cohort Colonies and Hormone Treatment of Worker Honeybees to Analyze Physiology Associated with Role and/or Endocrine System.

PubMed

Ueno, Takayuki; Kawasaki, Kiyoshi; Kubo, Takeo

2016-09-06

Honeybee workers are engaged in various tasks related to maintaining colony activity. The tasks of the workers change according to their age (age-related division of labor). Young workers are engaged in nursing the brood (nurse bees), while older workers are engaged in foraging for nectar and pollen (foragers). The physiology of the workers changes in association with this role shift. For example, the main function of the hypopharyngeal glands (HPGs) changes from the secretion of major royal jelly proteins (MRJPs) to the secretion of carbohydrate-metabolizing enzymes. Because worker tasks change as the workers age in typical colonies, it is difficult to discriminate the physiological changes that occur with aging from those that occur with the role shift. To study the physiological changes in worker tissues, including the HPGs, in association with the role shift, it would be useful to manipulate the honeybee colony population by preparing single-cohort colonies in which workers of almost the same age perform different tasks. Here we describe a detailed protocol for preparing single-cohort colonies for this analysis. Six to eight days after single-cohort colony preparation, precocious foragers that perform foraging tasks earlier than usual appear in the colony. Representative results indicated role-associated changes in HPG gene expression, suggesting role-associated HPG function. In addition to manipulating the colony population, analysis of the endocrine system is important for investigating role-associated physiology. Here, we also describe a detailed protocol for treating workers with 20-hydroxyecdysone (20E), an active form of ecdysone, and methoprene, a juvenile hormone analogue. The survival rate of treated bees was sufficient to examine gene expression in the HPGs. Gene expression changes were observed in response to 20E- and/or methoprene-treatment, suggesting that hormone treatments induce physiological changes of the HPGs. The protocol for hormone treatment described here is appropriate for examining hormonal effects on worker physiology.

Night shift work at specific age ranges and chronic disease risk factors

PubMed Central

Ramin, Cody; Devore, Elizabeth E; Wang, Weike; Pierre-Paul, Jeffrey; Wegrzyn, Lani R; Schernhammer, Eva S

2014-01-01

Objectives We examined the association of night shift work history and age when night shift work was performed with cancer and cardiovascular disease risk factors among 54 724 women in the Nurses' Health Study (NHS) II. Methods We calculated age-adjusted and socioeconomic status-adjusted means and percentages for cancer and cardiovascular risk factors in 2009 across categories of night shift work history. We used multivariable-adjusted logistic regression to estimate odds ratios (ORs) and 95% CIs for key risk factors among 54 724 participants (72% ever shift workers). We further examined these associations by age (20–25, 26–35, 36– 45 and 46+ years) at which shift work was performed. Results Ever night shift workers had increased odds of obesity (body mass index ≥30 kg/m2; OR=1.37, 95% CI 1.31 to 1.43); higher caffeine intake (≥131 mg/day; OR=1.16, 95% CI 1.12 to 1.22) and total calorie intake (≥1715 kcal/day; OR=1.09, 95% CI 1.04 to 1.13); current smoking (OR=1.30, 95% CI 1.19 to 1.42); and shorter sleep durations (≤7 h of sleep/day; OR=1.19, 95% CI 1.15 to 1.24) compared to never night shift workers. These estimates varied depending on age at which night work was performed, with a suggestion that night shift work before age 25 was associated with fewer risk factors compared to night shift work at older ages. Conclusions Our results indicate that night shift work may contribute to an adverse chronic disease risk profile, and that risk factors may vary depending on the age at which night shift work was performed. PMID:25261528

Rotator cuff strength balance in glovebox workers

DOE PAGES

Lawton, Cindy M.; Weaver, Amelia M.; Chan, Martha Kwan Yi; ...

2016-11-23

Gloveboxes are essential to the pharmaceutical, semi-conductor, nuclear, and biochemical industries. While gloveboxes serve as effective containment systems, they are often difficult to work in and present a number of ergonomic hazards. One such hazard is injury to the rotator cuff, a group of tendons and muscles in the shoulder, connecting the upper arm to the shoulder blade. Rotator cuff integrity is critical to shoulder health. This study compared the rotator cuff muscle strength ratios of glovebox workers to the healthy norm. Descriptive statistics were collected using a short questionnaire. Handheld dynamometry was used to quantify the ratio of forcesmore » produced for shoulder internal and external rotation. Results showed this population to have shoulder strength ratios significantly different from the healthy norm. Strength ratios were found to be a sound predictor of symptom incidence. The deviation from the normal ratio demonstrates the need for solutions designed to reduce the workload on the rotator cuff musculature in order to improve health and safety. Assessment of strength ratios can be used to screen for risk of symptom development. As a result, this increases technical knowledge and augments operational safety.« less

Rotator cuff strength balance in glovebox workers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawton, Cindy M.; Weaver, Amelia M.; Chan, Martha Kwan Yi

Gloveboxes are essential to the pharmaceutical, semi-conductor, nuclear, and biochemical industries. While gloveboxes serve as effective containment systems, they are often difficult to work in and present a number of ergonomic hazards. One such hazard is injury to the rotator cuff, a group of tendons and muscles in the shoulder, connecting the upper arm to the shoulder blade. Rotator cuff integrity is critical to shoulder health. This study compared the rotator cuff muscle strength ratios of glovebox workers to the healthy norm. Descriptive statistics were collected using a short questionnaire. Handheld dynamometry was used to quantify the ratio of forcesmore » produced for shoulder internal and external rotation. Results showed this population to have shoulder strength ratios significantly different from the healthy norm. Strength ratios were found to be a sound predictor of symptom incidence. The deviation from the normal ratio demonstrates the need for solutions designed to reduce the workload on the rotator cuff musculature in order to improve health and safety. Assessment of strength ratios can be used to screen for risk of symptom development. As a result, this increases technical knowledge and augments operational safety.« less

Perceptions of health stakeholders on task shifting and motivation of community health workers in different socio demographic contexts in Kenya (nomadic, peri-urban and rural agrarian)

PubMed Central

2014-01-01

Background The shortage of health professionals in low income countries is recognized as a crisis. Community health workers are part of a “task-shift” strategy to address this crisis. Task shifting in this paper refers to the delegation of tasks from health professionals to lay, trained volunteers. In Kenya, there is a debate as to whether these volunteers should be compensated, and what motivation strategies would be effective in different socio-demographic contexts, based type of tasks shifted. The purpose of this study was to find out, from stakeholders’ perspectives, the type of tasks to be shifted to community health workers and the appropriate strategies to motivate and retain them. Methods This was an analytical comparative study employing qualitative methods: key informant interviews with health policy makers, managers, and service providers, and focus group discussions with community health workers and service consumers, to explore their perspectives on tasks to be shifted and appropriate motivation strategies. Results The study found that there were tasks to be shifted and motivation strategies that were common to all three contexts. Common tasks were promotive, preventive, and simple curative services. Common motivation strategies were supportive supervision, means of identification, equitable allocation of resources, training, compensation, recognition, and evidence based community dialogue. Further, in the nomadic and peri-urban sites, community health workers had assumed curative services beyond the range provided for in the Kenyan task shifting policy. This was explained to be influenced by lack of access to care due to distance to health facilities, population movement, and scarcity of health providers in the nomadic setting and the harsh economic realities in peri-urban set up. Therefore, their motivation strategies included training on curative skills, technical support, and resources for curative care. Data collection was viewed as an important task in the rural site, but was not recognized as priority in nomadic and peri-urban sites, where they sought monetary compensation for data collection. Conclusions The study concluded that inclusion of curative tasks for community health workers, particularly in nomadic contexts, is inevitable but raises the need for accreditation of their training and regulation of their tasks. PMID:25079588

Biological monitoring of workers exposed to 4,4'-methylenediphenyl diisocyanate (MDI) in 19 French polyurethane industries.

PubMed

Robert, A; Ducos, P; Francin, J M; Marsan, P

2007-04-01

To study the range of urinary levels of 4,4'-methylenedianiline (MDA), a metabolite of methylenediphenyl diisocyanate (MDI), across factories in the polyurethane industries and to evaluate the validity of this biomarker to assess MDI occupational exposure. Workers exposed to MDI, as well as non-occupationally exposed subjects, were studied and pre- and post-shift urine samples were collected from 169 workers of 19 French factories and 120 controls. Details on work activities and practices were collected by a questionnaire and workers were classified into three job categories. The identification and quantification of the total urinary MDA were performed by high-performance liquid chromatography with electrochemical detection (HPLC/EC). For all the factories, MDA was detectable in 73% of the post-shift urine samples. These post-shift values, in the range of <0.10 (detection limit)-23.60 microg/l, were significantly higher than those of the pre-shift samples. Urinary MDA levels in the control group were in the range of < 0.10-0.80 microg/l. The degree of automation of the mixing operation (polyols and MDI) appears as a determinant in the extent of exposure levels. The highest amounts of MDA in urine were found in the spraying or hot processes. The excretion levels of the workers directly exposed to the hardener containing the MDI monomer were significantly higher than those of the other workers. In addition, skin exposure to MDI monomer or to polyurethane resin during the curing step were always associated with significant MDA levels in urine. Total MDA in post-shift urine samples is a reliable biomarker to assess occupational exposure to MDI in various industrial applications and to help factories to improve their manufacturing processes and working practices. A biological guiding value not exceeding 7 microg/l (5 microg/g creatinine) could be proposed in France.

Daytime Sleep Disturbance in Night Shift Work and the Role of PERIOD3.

PubMed

Cheng, Philip; Tallent, Gabriel; Burgess, Helen J; Tran, Kieulinh Michelle; Roth, Thomas; Drake, Christopher L

2018-03-15

Recent evidence indicates that daytime sleep disturbance associated with night shift work may arise from both circadian misalignment and sleep reactivity to stress. This presents an important clinical challenge because there are limited means of predicting and distinguishing between the two mechanisms, and the respective treatments differ categorically; however, there is support that a polymorphism in the PERIOD3 gene ( PER3 ) may indicate differences in vulnerability to daytime sleep disturbance in shift workers. We recruited 30 fixed night shift workers for laboratory assessments of circadian misalignment (dim light melatonin onset), sleep reactivity to stress (Ford Insomnia Response to Stress Test), daytime sleep disturbance (daytime Insomnia Severity Index), and PER3 genotype ( PER3 4/4 , PER3 5 /- ). The two mechanisms for daytime sleep disturbance (circadian misalignment and sleep reactivity to stress) were compared between PER3 genotypes. Disturbed daytime sleep in the PER3 4/4 group was more likely related to sleep reactivity to stress, whereas disturbed sleep in the PER3 5 /- group was more likely related to circadian misalignment. Exploratory analyses also revealed a blunted melatonin amplitude in the PER3 4/4 genotype group. This study provides further evidence for multiple mechanisms (ie, circadian misalignment versus sleep reactivity to stress) associated with daytime sleep disturbances in shift workers. Additionally, it provides the new finding that PER3 genotype may play an important role in individual vulnerability to the different mechanisms of daytime sleep disturbance in night shift workers. © 2018 American Academy of Sleep Medicine.

Postprandial metabolic profiles following meals and snacks eaten during simulated night and day shift work.

PubMed

Al-Naimi, S; Hampton, S M; Richard, P; Tzung, C; Morgan, L M

2004-01-01

Shift workers are known to have an increased risk of developing cardiovascular disease (CVD) compared with day workers. An important factor contributing to this increased risk could be the increased incidence of postprandial metabolic risk factors for CVD among shift workers, as a consequence of the maladaptation of endogenous circadian rhythms to abrupt changes in shift times. We have previously shown that both simulated and real shift workers showed relatively impaired glucose and lipid tolerance if a single test meal was consumed between 00:00-02:00 h (night shift) compared with 12:00-14:00 h (day shift). The objective of the present study was to extend these observations to compare the cumulative metabolic effect of consecutive snacks/meals, as might normally be consumed throughout a period of night or day shift work. In a randomized crossover study, eight healthy nonobese men (20-33 yrs, BMI 20-25kg/m2) consumed a combination of two meals and a snack on two occasions following a standardized prestudy meal, simulating night and day shift working (total energy 2500 kcal: 40% fat, 50% carbohydrate, 10% protein). Meals were consumed at 01:00/ 13:00 h and 07:00/19:00h, and the snack at 04:00/16:00 h. Blood was taken after an overnight fast, and for 8 h following the first meal on each occasion, for the measurement of glucose, insulin, triacylglycerol (TAG), and nonesterified fatty acids (NEFA). RM-ANOVA (factors time and shift) showed a significant effect of shift for plasma TAG, with higher levels on simulated night compared to day shift (p < 0.05). There was a trend toward an effect of shift for plasma glucose, with higher plasma glucose at night (p = 0.08), and there was a time-shift interaction for plasma insulin levels (p < 0.01). NEFA levels were unaffected by shift. Inspection of the area under the plasma response curve (AUC) following each meal and snack revealed that the differences in lipid tolerance occurred throughout the study, with greatest differences occurring following the mid-shift snack. In contrast, glucose tolerance was relatively impaired following the first night-time meal, with no differences observed following the second meal. Plasma insulin levels were significantly lower following the first meal (p < 0.05), but significantly higher following the second meal (p < 0.01) on the simulated night shift. These findings confirm our previous observations of raised postprandial TAG and glucose at night, and show that sequential meal ingestion has a more pronounced effect on subsequent lipid than carbohydrate tolerance.

Twenty-four/seven: a mixed-method systematic review of the off-shift literature

PubMed Central

de Cordova, Pamela B.; Phibbs, Ciaran S.; Bartel, Ann P.; Stone, Patricia W.

2012-01-01

Aim This article is a report of a review that aimed to synthesize qualitative and quantitative evidence of ‘off-shifts’ (nights, weekends and/or holidays) on quality and employee outcomes in hospitals. Background Healthcare workers provide 24-hour-a-day, 7-day-a-week service. Quality and employee outcomes may differ on off-shifts as compared to regular hours. Data sources Searches for studies occurred between the years 1985–2011 using computerized databases including Business Source Complete, EconLit, ProQuest, PubMed and MEDLINE. Review design and methods Design was a mixed-method systematic review with quantitative and qualitative studies. To be included, studies met the following criteria: (1) the independent variable was an off-shift; (2) the article was a research study and peer-reviewed; (3) the article could be obtained in English; and (4) the article pertained to health care. Studies were not excluded on design. Results Sixty studies were included. There were 37 quality outcome, 19 employee outcome and four qualitative studies. In the quality outcome studies, researchers often used quantitative, longitudinal study designs with large sample sizes. Researchers found important differences between patients admitted on weekends and mortality. Important differences were also found between nighttime birth and mortality and rotating night work and fatigue, stress and low mental well-being. Most studies (9 of 12) did not find an important association between patients admitted at night and mortality. Conclusion Patient outcomes on weekends and employee outcomes at night are worse than during the day. It is important to further investigate why care on off-shifts differs from weekly day shifts. PMID:22905343

Job Rotation Designed to Prevent Musculoskeletal Disorders and Control Risk in Manufacturing Industries: A Systematic Review

PubMed Central

Padula, Rosimeire Simprini; Comper, Maria Luiza Caires; Sparer, Emily H.; Dennerlein, Jack T

2017-01-01

To better understand job rotation in the manufacturing industry, we completed a systematic review asking the following questions: 1) How do job-rotation programs impact work-related musculoskeletal disorders (MSDs) and related risk control for these MSDs, as well as psychosocial factors? and 2) How best should the job rotation programs be designed? We searched MEDLINE, EMBASE, Business Source Premier, ISI Web of Knowledge, CINAHL, PsyINFO, Scopus, and SciELO databases for articles published in peer-reviewed journals. Eligible studies were examined by two independent reviewers for relevance (population of manufacturing workers, outcomes of musculoskeletal disease, physical factors, psychosocial factors, and strategies used in job-rotation implantation) and methodological quality rating. From 10,809 potential articles, 71 were read for full text analysis. Of the 14 studies included for data extraction, two were non-randomized control trial studies, one was a case-control study, and 11 were cross-sectional comparisons. Only one, with a case-control design, was scored with good methodological quality. Currently, weak evidence exists supporting job rotation as a strategy for the prevention and control of musculoskeletal disorders. Job rotation did not appear to reduce the exposure of physical risk factors; yet, there are positive correlations between job rotation and higher job satisfaction. Worker training has been described as a crucial component of a successful job-rotation program. The studies reported a range of parameters used to implement and measure job-rotation programs. More rigorous studies are needed to better understand the full impact of job rotation on production and health. PMID:27633235

76 FR 46852 - Panasonic Corporation of North America, Business Operations Group, Rolling Meadows, IL; Panasonic...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-03

... workers of the subject firm who were adversely affected by a shift in services to India. The amended... To Apply for Worker Adjustment Assistance In accordance with Section 223 of the Trade Act of 1974, as... Eligibility to Apply for Worker Adjustment Assistance on April 7, 2011, applicable to workers of Panasonic...

Shift work--problems and its impact on female nurses in Udaipur, Rajasthan India.

PubMed

Rathore, H; Shukla, K; Singh, S; Tiwari, G

2012-01-01

Abstract : There is good evidence that shift work has negative effects on workers health, safety and performance. It is quite appropriate that attention is paid to this very important feature of socio-technical systems, which may adversely affect mental and physical health, social life and safety of shift workers. Research into the impact of shift work on professionals has consistently identified a range of negative outcomes in physical, psychological, and social domains (Akerstedt, 1988; Costa, Lievore, Casaletti, Gaffuri, & Folkard, 1989; Kogi, 2005; Paley & Tepas, 1994). Hospitals, the biggest employer in the health care field, employ more night shift workers than any other industry. It can therefore be inferred that in medical domain high percentage of workforce may be affected by problems related to shift work. Thus the present study will provide knowledge base for the problems faced by the female nurses. The present study was undertaken with an objective of getting an insight into the problems faced by female nurses in shift work. . It was found that the female nurses in India worked on roaster pattern of change in shift every seven days. They did not have a say in the change of duties, it could only be done on mutual grounds. Partners of younger group did not much adjust to their shift pattern this created stress among the nurses.The results showed that the female nurses in both the age groups i.e. 30-45 years and 45-60 years faced many problems related to health and well being, fatigue, social and domestic situations. They could not give much time to their children in particular. Travelling in nights was risky for them. Common problem was the insufficient sleep during night shifts. The nurses had to cater to the needs of the family, children in particular along with the adjustments to be made due to shift work. They had to sometimes do the night duties and attend social functions as a part of their duty. Children and husband in some cases did not cooperate this lead to frustration. When asked as to whether they would could shift job if they get regular one more than 50 % said yes this means that there need to be come training and intervention for the shift workers and their family so that the problems faced and their impact on personal health of the female nurses could be reduced.

Effects of Shift and Night Work in the Offshore Petroleum Industry: A Systematic Review

PubMed Central

FOSSUM, Ingrid Nesdal; BJORVATN, Bjørn; WAAGE, Siri; PALLESEN, Ståle

2013-01-01

Shift and night work are associated with several negative outcomes. The aim of this study was to make a systematic review of all studies which examine effects of shift and night work in the offshore petroleum industry, to synthesize the knowledge of how shift work offshore may affect the workers. Searches for studies concerning effects on health, sleep, adaptation, safety, working conditions, family- and social life and turnover were conducted via the databases Web of Knowledge, PsycINFO and PubMed. Search was also conducted through inspection of reference lists of relevant literature. We identified studies describing effects of shift work in terms of sleep, adaptation and re-adaptation of circadian rhythms, health outcomes, safety and accidents, family and social life, and work perceptions. Twenty-nine studies were included. In conclusion, the longitudinal studies were generally consistent in showing that adaptation to night work was complete within one to two weeks of work, while re-adaptation to a daytime schedule was slower. Shift workers reported more sleep problems than day workers. The data regarding mental and physical health, family and social life, and accidents yielded inconsistent results, and were insufficient as a base for drawing general conclusions. More research in the field is warranted. PMID:23803497

Noninvasive method for assessing the human circadian clock using hair follicle cells

PubMed Central

Akashi, Makoto; Soma, Haruhiko; Yamamoto, Takuro; Tsugitomi, Asuka; Yamashita, Shiko; Yamamoto, Takuya; Nishida, Eisuke; Yasuda, Akio; Liao, James K.; Node, Koichi

2010-01-01

A thorough understanding of the circadian clock requires qualitative evaluation of circadian clock gene expression. Thus far, no simple and effective method for detecting human clock gene expression has become available. This limitation has greatly hampered our understanding of human circadian rhythm. Here we report a convenient, reliable, and less invasive method for detecting human clock gene expression using biopsy samples of hair follicle cells from the head or chin. We show that the circadian phase of clock gene expression in hair follicle cells accurately reflects that of individual behavioral rhythms, demonstrating that this strategy is appropriate for evaluating the human peripheral circadian clock. Furthermore, using this method, we indicate that rotating shift workers suffer from a serious time lag between circadian gene expression rhythms and lifestyle. Qualitative evaluation of clock gene expression in hair follicle cells, therefore, may be an effective approach for studying the human circadian clock in the clinical setting. PMID:20798039

Association of salivary cortisol with chronomics of 24 hours ambulatory blood pressure/heart rate among night shift workers.

PubMed

Anjum, B; Verma, N S; Tiwari, S; Singh, R; Mahdi, A A; Singh, R B; Singh, R K

2011-08-01

Recent studies indicate a circadian rhythm in blood pressure and heart rate and its association with various neurotransmitters. In the present study, we examine the circadian nature of blood pressure/heart rate and salivary cortisol in night shift workers and whether these circadian changes produced by night shifts are reversible. Sixteen healthy nurses of both genders, aged 20-40 years, performing day and night shift duties, were randomly selected out of 22 who volunteered for this study. Ambulatory blood pressure monitoring was done in all the subjects and salivary cortisol levels were analyzed during both day and night shift duties. There were clinically significant changes in the Acrophase of blood pressure and cortisol levels, indicating ecphasia (odd timing of systolic blood pressure) individually during night as well as day shifts. However, this pattern was statistically not significant. A reverse pattern of Acrophase was observed in 8 out of 16 subjects when they were posted on day shift. No significant change was found in midline estimating statistics of rhythm (MESOR) of blood pressure values. Changes in Double amplitude (Predictable change) were observed in 8 subjects during night shifts as well as in 7 subjects during day shifts. However, the pattern was not similar and night workers had an altered circadian pattern in the night as well as during day shifts. Changes in Double amplitude, Acrophase and Salivary cortisol were found during night as well as day shifts but these changes were not statistically significant (p > 0.05) due to incomplete recovery during day shifts (changes again seen when they came back to day shifts). Salivary cortisol levels were lowest in early morning, increased at midnight and further increased in the afternoon during night shifts along with ecphasia. It is possible that nurses working the night shift felt more tired due to the altered circadian cycle.

Nasal lavage cellularity, grain dust, and airflow obstruction.

PubMed

Blaski, C A; Watt, J L; Quinn, T J; Thorne, P S; Schwartz, D A

1996-04-01

To evaluate the clinical utility of nasal lavage (NL), we performed post-work shift NL on 172 grain workers and 78 postal worker control subjects. The grain worker group included a higher percentage of current smokers (25.7% vs 16.7%) and a lower percentage of former smokers (21.15% vs 35.9%) compared with the postal workers. The control subjects included more female workers and were slightly older than the grain workers. Compared with the postal workers, the grain workers were exposed to significantly greater concentrations of total dust (0.1 +/- 0.0 vs 6.8 +/- 1.4 mg/m3; mean +/- SEM) and total endotoxin (4.3 +/- 0.8 vs 2,372.4 +/- 653.8 endotoxin units/m3). NL from gain workers showed a higher concentration of total cells (55,000 +/- 14,000 vs 25,000 +/- 5,000 cells per milliliter; p=0.03), a higher concentration of squamous epithelial cells (17,029.0 +/- 4,177 .0 vs 7,103.7 +/- 1,479.8 cells per milliliter; p=0.03), and a higher concentration of neutrophils (40,058.0 +/- 12,803.2 vs 17,891.0 +/- 3,822.3 cells per milliliter; p=0.10) compared with postal workers. Importantly, these differences in NL cellularity between grain workers and postal workers were observed within the three strata of smokers. To further assess the importance of total cells, squamous epithelial cells, and neutrophils in the NL fluid of grain workers, we investigated the relationship between these cell concentrations and (1) measures of dust and endotoxin exposure during the work shift. (2) spirometric measures of airflow obtained immediately before the NL, and (3) work-related respiratory symptoms. The concentration of total cells, the concentration of squamous epithelial cells, or the concentration of neutrophils in the NL was not associated with ambient levels of dust or endotoxin, with baseline or cross-shift changes in lung function, or with work-related respiratory symptoms. These findings suggest that increased NL cellularity may be seen in workers exposed to high dust levels. However, the NL cellularity does not appear to be associated with ambient concentrations of dusts or endotoxins, with signs of airflow obstruction, or with work-related respiratory symptoms.

Exercise, Energy Balance and the Shift Worker

PubMed Central

Atkinson, Greg; Fullick, Sarah; Grindey, Charlotte; Maclaren, Don; Waterhouse, Jim

2009-01-01

Shift work is now common in society and is not restricted to heavy industry or emergency services, but is increasingly found amongst ‘white collar’ occupations and the growing number of service industries. Participation in shift work is associated with increased body mass index, prevalence of obesity and other health problems. We review the behavioural and biological disturbances that occur during shift work and discuss their impact on leisure-time physical activity and energy balance. Shift work generally decreases opportunities for physical activity and participation in sports. For those shift workers who are able to exercise, subjective and biological responses can be altered if the exercise is taken at unusual times of day and/or if the shift worker is sleep-deprived. These altered responses may in turn impact on the longer-term adherence to an exercise programme. The favourable effects of exercise on body mass control and sleep quality have not been confirmed in shift workers. Similarly, recent reports of relationships between sleep duration and obesity have not been examined in a shift work context. There is no evidence that exercise can mediate certain circadian rhythm characteristics (e.g. amplitude or timing) for improved tolerance to shift work. Total energy intake and meal composition do not seem to be affected by participation in shift work. Meal frequency is generally reduced but snacking is increased on the night shift. Unavailability of preferred foods in the workplace, a lack of time, and a reduced desire to eat at night explain these findings. ‘Normal’ eating habits with the family are also disrupted. The metabolic responses to food are also altered by shift work-mediated disruptions to sleep and circadian rhythms. Whether any interactions on human metabolism exist between timing or content of food intake and physical activity during shift work is not known at present. There are very few randomised controlled studies on the efficacy of physical activity or dietary interventions during shift work. Some favourable effects of such interventions on fatigue levels at work have been reported, but biological and behavioural outcomes relevant to long-term health and energy balance have not been studied adequately. In addition, recruitment and retention of research participants for randomised controlled trials of physical activity or dietary interventions has been very difficult. We present a model of the various behavioural and biological factors relevant to exercise and energy balance during shift work as a framework for future research. PMID:18620467

The factor harmful to the quality of human life--shift-work.

PubMed

Strzemecka, Joanna; Pencuła, Marcin; Owoc, Alfred; Szot, Wojciech; Strzemecka, Ewa; Jabłoński, Mirosław; Bojar, Iwona

2013-01-01

The system of human activity, which is established by genetics and regulated by outer and inner factors, is associated with many characteristics which maintain the body in the best condition and ensure appropriate life quality. To evaluate of life quality among male shift-workers. Research based on a self-devised questionnaire, conducted among 700 shift-workers, followed by statistical analysis of the results. Nearly a half of respondents (43.00%) reported that shift-work influences the quality of their family life. Remarkably, such an opinion was often stated by people with children (46.01%) p<0.05, the divorced (58.22%), married people (44.74%) and bachelors (25.33%), respectively. Fathers usually indicated lack of contact with their family as well as irregular consumption of meals (66.91%). Almost every third respondent noted that their shift type of work negatively influence their sexual life (31.14%). It was shown that shift-work negatively influences the respondents' life quality in the form of deterioration of the quality of family life; the respondents, regardless of marital status, age and having children, most often complained about the lack of contact with the family and irregular eating with them; negative influence on sexual life, which was the case in one-third of respondents. In order to encourage healthy behaviour and increase the quality of life of people performing shift-work, training and programmes should be introduced. These would help shift- workers to adjust their work time to their family and social life.

Effects of Fatigue on Driving Safety: A Comparison of Brake Reaction Times in Night Float and Postcall Physicians in Training.

PubMed

Talusan, Paul G; Long, Theodore; Halim, Andrea; Guliani, Laura; Carroll, Nicole; Reach, John

2014-12-01

Concerns about duty hour and resident safety have fostered discussion about postshift fatigue and driving impairment. We assessed how converting to a night float schedule for overnight coverage affected driving safety for trainees. Brake reaction times were measured for internal medicine and orthopaedic surgery resident volunteers after a traditional 28-hour call shift and after a night float shift. We conducted matched paired t tests of preshift and postshift reaction time means. Participants also completed the Epworth Sleepiness Scale pre- and postshift. From June to July 2013, we enrolled 58 interns and residents (28 orthopaedic surgery, 30 internal medicine). We included 24 (41%) trainees on night float rotations and 34 (59%) trainees on traditional 28-hour call shifts. For all residents on night float rotations, there was no significant difference pre- and postshift. An increase in reaction times was noted among trainees on 28-hour call rotations. This included no effect on reaction times for internal medicine trainees pre- and postshift, and an increase in reaction times for orthopaedic trainees. For both night float and traditional call groups, there were significant increases in the Epworth Sleepiness Scale. Trainees on traditional 28-hour call rotations had significantly worse postshift brake reaction times, whereas trainees on night float rotations had no difference. Orthopaedic trainees had significant differences in brake reaction times after a traditional call shift.

Work-Related Pain and Injury and Barriers to Workers’ Compensation Among Las Vegas Hotel Room Cleaners

PubMed Central

Scherzer, Teresa; Rugulies, Reiner; Krause, Niklas

2005-01-01

Objectives. We examined the prevalence of work-related pain and injury and explored barriers to and experiences of reporting among workers. Methods. We surveyed 941 unionized hotel room cleaners about work-related pain, injury, disability, and reporting. Results. During the past 12 months, 75% of workers in our study experienced work-related pain, and 31% reported it to management; 20% filed claims for workers’ compensation as a result of work-related injury, and 35% of their claims were denied. Barriers to reporting injury included “It would be too much trouble” (43%), “I was afraid” (26%), and “I didn’t know how” (18%). An estimated 69% of medical costs were shifted from employers to workers. Conclusions. The reasons for underreporting and the extent of claim denial warrant further investigation. Implications for worker health and the precise quantification of shifting costs to workers also should be addressed. PMID:15727981

When is job rotation perceived useful and easy to use to prevent work-related musculoskeletal complaints?

PubMed

Leider, Priscilla C; Boschman, Julitta S; Frings-Dresen, Monique H W; van der Molen, Henk F

2015-11-01

Job rotation is often recommended to optimize physical work demands and prevent work-related musculoskeletal complaints, but little is known about possible facilitators and barriers to its usefulness and ease of use. Following a qualitative research design, semi-structured interviews with employers (n = 12) and workers (n = 11) from the construction industry were conducted. Organizational climate, job autonomy, job characteristics and work processes were mentioned as either facilitators or barriers on an organizational level. Worker characteristics, work behavior and attitude were mentioned as either facilitators or barriers on an individual level. Following a structured approach to assess usefulness of job rotation to optimize physical work exposures and identifying barriers to usefulness and ease of use in relevant stakeholder groups is necessary in order to select or develop strategies to overcome these barriers, or to reject job rotation as a useful or easy to use intervention in the given context. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

A longitudinal study of the influence of shift work on serum uric acid levels in workers at a telecommunications company.

PubMed

Uetani, Mirei; Suwazono, Yasushi; Kobayashi, Etsuko; Inaba, Takeya; Oishi, Mitsuhiro; Nogawa, Koji

2006-03-01

Hyperuricemia is a lifestyle-related disease. Although there have been many previous reports about the association of serum uric acid (UA) levels with lifestyle, including eating habits and alcohol intake, there has been no report of a longitudinal study of the relationship between serum UA levels and shift work. To clarify the influence of shift work on serum UA levels in Japanese workers. This was a 4-year cohort study of 15 871 workers at a telecommunications company. Pooled logistic regression analyses by sex were performed, with job schedule type, age, body mass index (BMI), lifestyle and the results of blood chemistries as covariates. In males, shift work, part-time work, BMI, consumption of alcohol (less than twice per week, two to five times per week or more than five times per week) and little preference for vegetables were positively associated with the development of increased serum UA (>or=8 mg/dl in males, >or=6 mg/dl in females). In females, age, BMI and a history of smoking were positively associated with the development of increased serum UA. This study revealed that shift work is independently related to increased serum UA in males.

Are chronotype, social jetlag and sleep duration associated with health measured by Work Ability Index?

PubMed

Yong, Mei; Fischer, Dorothee; Germann, Christina; Lang, Stefan; Vetter, Céline; Oberlinner, Christoph

The present study investigates the impact of chronotype, social jetlag and sleep duration on self-perceived health, measured by Work Ability Index (WAI), within an industrial setting. Between 2011 and 2013, 2474 day and shift workers participated in a health check offered by an occupational health promotion program and filled out the Munich ChronoType Questionnaire (adapted to the rotational 12-h schedule for shift workers) and the WAI. We computed sleep duration on work and free days, chronotype, and social jetlag. We used linear regression models to examine chronotype, sleep duration and social jetlag for association with the WAI sum score, and proportional odds models to estimate the combined effect of social jetlag and sleep duration. Participants reported an average daily sleep duration of 7.35 h (SD: 1.2 h), had an average chronotype of 3:08 a.m. (SD: 1 h), and the average social jetlag corresponded to 1.96 h (SD: 2.05 h). Increasing social jetlag and shorter sleep duration were independently associated with a decreasing WAI, while chronotype per se was not associated with WAI. Short sleep duration combined with high social jetlag significantly increased the risk of poor WAI (OR = 1.36; 95% CI: 1.09-1.72), while long sleep duration and high social jetlag were not associated with poor WAI (OR = 1.09; 95% CI: 0.88-1.35). Our results add to a growing body of literature, suggesting that circadian misalignment, but not chronotype per se, may be critical for health. Our results indicate that longer sleep may override the adverse effects of social jetlag on WAI.

Concurrent error detecting codes for arithmetic processors

NASA Technical Reports Server (NTRS)

Lim, R. S.

1979-01-01

A method of concurrent error detection for arithmetic processors is described. Low-cost residue codes with check-length l and checkbase m = 2 to the l power - 1 are described for checking arithmetic operations of addition, subtraction, multiplication, division complement, shift, and rotate. Of the three number representations, the signed-magnitude representation is preferred for residue checking. Two methods of residue generation are described: the standard method of using modulo m adders and the method of using a self-testing residue tree. A simple single-bit parity-check code is described for checking the logical operations of XOR, OR, and AND, and also the arithmetic operations of complement, shift, and rotate. For checking complement, shift, and rotate, the single-bit parity-check code is simpler to implement than the residue codes.

Time savings--realized and potential--and fair compensation for community health workers in Kenyan health facilities: a mixed-methods approach.

PubMed

Sander, Laura D; Holtzman, David; Pauly, Mark; Cohn, Jennifer

2015-01-30

Sub-Saharan Africa faces a severe health worker shortage, which community health workers (CHWs) may fill. This study describes tasks shifted from clinicians to CHWs in Kenya, places monetary valuations on CHWs' efforts, and models effects of further task shifting on time demands of clinicians and CHWs. Mixed methods were used for this study. Interviews were conducted with 28 CHWs and 19 clinicians in 17 health facilities throughout Kenya focusing on task shifting involving CHWs, time savings for clinicians as a result of task shifting, barriers and enabling factors to CHWs' work, and appropriate CHW compensation. Twenty CHWs completed task diaries over a 14-day period to examine current CHW tasks and the amount of time spent performing them. A modeling exercise was conducted examining a current task-shifting example and another scenario in which additional task shifting to CHWs has occurred. CHWs worked an average of 5.3 hours per day and spent 36% of their time performing tasks shifted from clinicians. We estimated a monthly valuation of US$ 117 per CHW. The modeling exercise demonstrated that further task shifting would reduce the number of clinicians needed while maintaining clinic productivity by significantly increasing the number of CHWs. CHWs are an important component of healthcare delivery in Kenya. Our monetary estimates of current CHW contributions provide starting points for further discussion, research and planning regarding CHW compensation and programs. Additional task shifting to CHWs may further offload overworked clinicians while maintaining overall productivity.

Impact of shift work on sleep and daytime performance among health care professionals.

PubMed

Alshahrani, Sultan M; Baqays, Abdulsalam A; Alenazi, Abdelelah A; AlAngari, Abdulaziz M; AlHadi, Ahmad N

2017-08-01

To evaluate sleep quality and daytime sleepiness in health care professionals who are performing shift work. Methods: This cross-sectional study was conducted on 510 health care professionals at Prince Sultan Military Medical City and King Khalid University Hospital, King Saud University, Riyadh, Kingdom of Saudi Arabia between December 2015 and April 2016. Data were collected using the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). Participants were divided into 2 groups: shift workers and non-shift workers. Results: We compared both groups regarding the effect of shift work on the total score of PSQI and ESS. We found that the PSQI global score (p less than 0.001) and the total ESS score (p=0.003) were significantly higher in shift work health care professionals.  Conclusion: Shift work among health care professionals is associated with poor sleep quality but not excessive daytime sleepiness. Health care professionals performing shift work have PSQI and ESS scores slightly higher than non-shift work health professionals.

Medial Entorhinal Grid Cells and Head Direction Cells Rotate with a T-Maze More Often During Less Recently Experienced Rotations

PubMed Central

Gupta, Kishan; Beer, Nathan J.; Keller, Lauren A.; Hasselmo, Michael E.

2014-01-01

Prior studies of head direction (HD) cells indicate strong landmark control over the preferred firing direction of these cells, with few studies exhibiting shifts away from local reference frames over time. We recorded spiking activity of grid and HD cells in the medial entorhinal cortex of rats, testing correlations of local environmental cues with the spatial tuning curves of these cells' firing fields as animals performed continuous spatial alternation on a T-maze that shared the boundaries of an open-field arena. The environment was rotated into configurations the animal had either seen or not seen in the past recording week. Tuning curves of both cell types demonstrated commensurate shifts of tuning with T-maze rotations during less recent rotations, more so than recent rotations. This strongly suggests that animals are shifting their reference frame away from the local environmental cues over time, learning to use a different reference frame more likely reliant on distal or idiothetic cues. In addition, grid fields demonstrated varying levels of “fragmentation” on the T-maze. The propensity for fragmentation does not depend on grid spacing and grid score, nor animal trajectory, indicating the cognitive treatment of environmental subcompartments is likely driven by task demands. PMID:23382518

[Comparative study of sleep patterns in nurses working day and night shifts].

PubMed

De Martino, Milva Maria Figueiredo

2002-08-01

To compare sleep patterns in nurses working day and night shifts in a hospital in Campinas (SP), Brazil. Fifty-nine nurses between 23 and 59 years of age participated in the study. For day shift workers, the pattern of nocturnal sleep was examined; for night shift workers, nocturnal and diurnal sleep patterns were examined. During 1 week, participants filled out a sleep diary right after waking up. The following items were assessed: time going to bed, falling asleep, and waking up; sleep latency; duration in hours of nocturnal and diurnal sleep; naps; quality of sleep; mode of waking up; and comparison between the sleep recorded in the diary with the usual sleep. Personal and professional information was also collected. Day shift workers went to bed at 23h36min, and night workers at 23h52min (P > 0.05). The nurses working a day schedule woke up earlier (7h3min) than those working a night schedule when they slept at night (8h30min) (P

76 FR 16450 - Management Resources Group, Inc., Including Workers in the States of Georgia and New York...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-23

...) there has been a shift by the workers' firm to a foreign country in the production of articles or supply...) there has been an acquisition from a foreign country by the workers' firm of articles/services that are.... Further, the Department determined that workers in the Inventory Services Group, which performs activities...

Time-motion analysis as a novel approach for evaluating the impact of environmental heat exposure on labor loss in agriculture workers

PubMed Central

Ioannou, Leonidas G.; Tsoutsoubi, Lydia; Samoutis, George; Bogataj, Lucka Kajfez; Kenny, Glen P.; Kjellstrom, Tord

2017-01-01

ABSTRACT Introduction: In this study we (i) introduced time-motion analysis for assessing the impact of workplace heat on the work shift time spent doing labor (WTL) of grape-picking workers, (ii) examined whether seasonal environmental differences can influence their WTL, and (iii) investigated whether their WTL can be assessed by monitoring productivity or the vineyard manager's estimate of WTL. Methods: Seven grape-picking workers were assessed during the summer and/or autumn via video throughout four work shifts. Results: Air temperature (26.8 ± 4.8°C), wet bulb globe temperature (WBGT; 25.2 ± 4.1°C), universal thermal climate index (UTCI; 35.2 ± 6.7°C), and solar radiation (719.1 ± 187.5 W/m2) were associated with changes in mean skin temperature (1.7 ± 1.8°C) (p < 0.05). Time-motion analysis showed that 12.4% (summer 15.3% vs. autumn 10.0%; p < 0.001) of total work shift time was spent on irregular breaks (WTB). There was a 0.8%, 0.8%, 0.6%, and 2.1% increase in hourly WTB for every degree Celsius increase in temperature, WBGT, UTCI, and mean skin temperature, respectively (p < 0.01). Seasonal changes in UTCI explained 64.0% of the seasonal changes in WTL (p = 0.017). Productivity explained 36.6% of the variance in WTL (p < 0.001), while the vineyard manager's WTL estimate was too optimistic (p < 0.001) and explained only 2.8% of the variance in the true WTL (p = 0.456). Conclusion: Time-motion analysis accurately assesses WTL, evaluating every second spent by each worker during every work shift. The studied grape-picking workers experienced increased workplace heat, leading to significant labor loss. Monitoring productivity or the vineyard manager's estimate of each worker's WTL did not completely reflect the true WTL in these grape-picking workers. PMID:28944274

Task-shifting point-of-care CD4+ testing to lay health workers in HIV care and treatment services in Namibia.

PubMed

Kaindjee-Tjituka, Francina; Sawadogo, Souleymane; Mutandi, Graham; Maher, Andrew D; Salomo, Natanael; Mbapaha, Claudia; Neo, Marytha; Beukes, Anita; Gweshe, Justice; Muadinohamba, Alexinah; Lowrance, David W

2017-01-01

Access to CD4+ testing remains a common barrier to early initiation of antiretroviral therapy among persons living with HIV/AIDS in low- and middle-income countries. The feasibility of task-shifting of point-of-care (POC) CD4+ testing to lay health workers in Namibia has not been evaluated. From July to August 2011, Pima CD4+ analysers were used to improve access to CD4+ testing at 10 selected public health facilities in Namibia. POC Pima CD4+ testing was performed by nurses or lay health workers. Venous blood samples were collected from 10% of patients and sent to centralised laboratories for CD4+ testing with standard methods. Outcomes for POC Pima CD4+ testing and patient receipt of results were compared between nurses and lay health workers and between the POC method and standard laboratory CD4+ testing methods. Overall, 1429 patients received a Pima CD4+ test; 500 (35.0%) tests were performed by nurses and 929 (65.0%) were performed by lay health workers. When Pima CD4+ testing was performed by a nurse or a lay health worker, 93.2% and 95.2% of results were valid ( p = 0.1); 95.6% and 98.1% of results were received by the patient ( p = 0.007); 96.2% and 94.0% of results were received by the patient on the same day ( p = 0.08). Overall, 97.2% of Pima CD4+ results were received by patients, compared to 55.4% of standard laboratory CD4+ results ( p < 0.001). POC CD4+ testing was feasible and effective when task-shifted to lay health workers. Rollout of POC CD4+ testing via task-shifting can improve access to CD4+ testing and retention in care between HIV diagnosis and antiretroviral therapy initiation in low- and middle-income countries.

The effect of work shift configurations on emergency medical dispatch center response.

PubMed

Montassier, Emmanuel; Labady, Julien; Andre, Antoine; Potel, Gilles; Berthier, Frederic; Jenvrin, Joel; Penverne, Yann

2015-01-01

It has been proved that emergency medical dispatch centers (EMDC) save lives by promoting an appropriate allocation of emergency medical service resources. Indeed, optimal dispatcher call duration is pivotal to reduce the time gap between the time a call is placed and the delivery of medical care. However, little is known about the impact of work shift configurations (i.e., work shift duration and work shift rotation throughout the day) and dispatcher call duration. Thus, the objective of our study was to assess the effect of work shift configurations on dispatcher call duration. During a 1-year study period, we analyzed the dispatcher call durations for medical and trauma calls during the 4 different work shift rotations (day, morning, evening, and night) and during the 10-hour work shift of each dispatcher in the EMDC of Nantes. We extracted dispatcher call durations from our advanced telephone system, configured with CC Pulse + (Genesys, Alcatel Lucent), and collected them in a custom designed database (Excel, Microsoft). Afterward, we analyzed these data using linear mixed effects models. During the study period, our EMDC received 408,077 calls. Globally, the mean dispatcher call duration was 107 ± 45 seconds. Based on multivariate linear mixed effects models, the dispatcher call duration was affected by night work shift and work shift duration greater than 8 hours, increasing it by about 10 ± 1 seconds and 4 ± 1 seconds, respectively (both p < 0.001). Our study showed that there was a statistically significant difference in dispatcher call duration over work shift rotation and duration, with longer durations seen over night shifts and shifts over 8 hours. While these differences are small and may not have clinical significance, they may have implications for EMDC efficiency.

[Possibilities and limits of sleep recovery for night-nursing workers].

PubMed

de Medeiros, Soraya Maria; de Macêdo, Maria Lúcia Azevedo Ferreira; de Oliveira, Jonas Sâmi Albuquerque; Ribeiro, Laiane Medeiros

2009-03-01

The present study had the objective of investigating the possibilities/limits of sleep recovery in women workers with medium level in nursing that develop their activities in night shifts in a first-aid clinic at a public hospital in Natal, Rio Grande do Norte, Brazil. This was an analytic study, with a qualitative approach which used the technique of thematic oral history Fifteen women workers with medium level in nursing were interviewed. The following empirical categories were defined: night shift work and night sleep and night rest at work environment Physiological and psychological sufferings are evident on their speech as well as what the lack of sleep causes in health and personal life of these women workers, making the overload of work clear and also the sociocultural imperfections of feminine gender

An In Vitro Robotic Assessment of the Anterolateral Ligament, Part 1: Secondary Role of the Anterolateral Ligament in the Setting of an Anterior Cruciate Ligament Injury.

PubMed

Rasmussen, Matthew T; Nitri, Marco; Williams, Brady T; Moulton, Samuel G; Cruz, Raphael Serra; Dornan, Grant J; Goldsmith, Mary T; LaPrade, Robert F

2016-03-01

Recent investigations have described the structural and functional behavior of the anterolateral ligament (ALL) of the knee through pull-apart and isolated sectioning studies. However, the secondary stabilizing role of the ALL in the setting of a complete anterior cruciate ligament (ACL) tear has not been fully defined for common simulated clinical examinations, such as the pivot-shift, anterior drawer, and internal rotation tests. Combined sectioning of the ALL and ACL would lead to increased internal rotation and increased axial plane translation during a pivot-shift test when compared with isolated sectioning of the ACL. Controlled laboratory study. Ten fresh-frozen human cadaveric knees were subjected to a simulated pivot-shift test with coupled 10-N·m valgus and 5-N·m internal rotation torques from 0° to 60° of knee flexion and a 5-N·m internal rotation torque and an 88-N anterior tibial load, both from 0° to 120° of knee flexion via a 6 degrees of freedom robotic system. Kinematic changes were measured and compared with the intact state for isolated sectioning of the ACL and combined sectioning of the ACL and ALL. Combined sectioning of the ACL and ALL resulted in a significant increase in axial plane tibial translation during a simulated pivot shift at 0°, 15°, 30°, and 60° of knee flexion and a significant increase in internal rotation at 0°, 15°, 30°, 45°, 60°, 75°, 90°, 105°, and 120° when compared with the intact and ACL-deficient states. Based on the model results, ALL sectioning resulted in an additional 2.1 mm (95% CI, 1.4-2.9 mm; P < .001) of axial plane translation during the pivot shift when compared with ACL-only sectioning, when pooling evidence over all flexion angles. Likewise, when subjected to IR torque, the ACL+ALL-deficient state resulted in an additional 3.2° of internal rotation (95% CI, 2.4°-4.1°; P < .001) versus the intact state, and the additional sectioning of the ALL increased internal rotation by 2.7° (95% CI, 1.8°-3.6°; P < .001) versus the ACL-deficient state. The results of this study confirm the ALL as an important lateral knee structure that provides rotatory stability to the knee. Specifically, the ALL was a significant secondary stabilizer throughout flexion during an applied internal rotation torque and simulated pivot-shift test in the context of an ACL-deficient knee. Residual internal rotation and a positive pivot shift after ACL reconstruction may be attributed to ALL injury. For these patients, surgical treatment of an ALL tear may be considered. © 2015 The Author(s).

Psychosocial work characteristics predicting daytime sleepiness in day and shift workers.

PubMed

Takahashi, Masaya; Nakata, Akinori; Haratani, Takashi; Otsuka, Yasumasa; Kaida, Kosuke; Fukasawa, Kenji

2006-01-01

Characteristics of work organization other than working time arrangements may contribute importantly to daytime sleepiness. The present study was designed to identify the psychosocial factors at work that predict daytime sleepiness in a sample of day and shift workers. Participants working at a pulp and chemical factory completed an annual questionnaire regarding psychosocial factors at work using the U.S. National Institute for Occupational Safety and Health Generic Job Stress Questionnaire (i.e., quantitative workload, variance in workload, job control, support from supervisor, coworkers, or family/friends, job satisfaction, and depressive symptoms), as well as daytime sleepiness (through the Epworth Sleepiness Scale [ESS]) and sleep disturbances for three years starting in 2002 (response rates, 94.6-99.0%). The present analysis included 55 day workers (11 women) and 57 shift workers (all men) who participated in all three years of the study, worked under the same work schedule throughout the study period, and had no missing data on any of the daytime sleep items. A repeated-measures analysis of covariance (ANCOVA) was used to test the effects of work schedule (day vs. shift work) and psychosocial factors at work in 2002 on the ESS scores in subsequent years, with sleep duration, insomnia symptoms, chronic diseases, and sleepiness levels at baseline as covariates. Given significant and near-significant interactions of work schedules with psychosocial factor or study year, the ANCOVA, with the factors of psychosocial work characteristics and study year, was performed by type of work schedule. The results indicated a significant main effect of psychosocial work characteristics (p = 0.010, partial eng2 = 0.14) and an almost significant main effect of study year (p = 0.067, partial eng2 = 0.06) and interaction between psychosocial work characteristics and study year (p = 0.085, partial eng2 = 0.06) for variance in workload among the day work group. The day workers reporting high variance in workload in 2002 exhibited significantly higher ESS scores in 2003 and 2004 than did those reporting low variance in workload. The ANCOVA for the shift work group showed a main effect of psychosocial work characteristics for job satisfaction (p = 0.026, partial eng2 = 0.10) and depressive symptoms (p = 0.094, partial eng2 = 0.06) with the interaction between psychosocial work characteristics and study year for job satisfaction (p = 0.172, partial eng2 = 0.04) and depressive symptoms (p = 0.035, partial eng2 = 0.07). The shift workers with low job satisfaction and high symptoms of depression in 2002 showed significantly greater ESS scores in 2003 and/or 2004 than did those with opposite characteristics. These results may suggest a potential predictive value of variance in workload for day workers as well as job satisfaction and depressive symptoms for shift workers with respect to daytime sleepiness. The present findings may imply that redesigning these aspects of work environment would be of help in managing daytime sleepiness.

Effects of Accumulating Work Shifts on Performance-Based Fatigue Using Multiple Strength Measurements in Day and Night Shift Nurses and Aides.

PubMed

Thompson, Brennan J; Stock, Matt S; Banuelas, Victoria K

2017-05-01

Objective This study aimed to examine the effects of accumulating nursing work on maximal and rapid strength characteristics in female nurses and compare these effects in day versus night shift workers. Background Nurses exhibit among the highest nonfatal injury rates of all occupations, which may be a consequence of long, cumulative work shift schedules. Fatigue may accumulate across multiple shifts and lead to performance impairments, which in turn may be linked to injury risks. Method Thirty-seven nurses and aides performed isometric strength-based performance testing of three muscle groups, including the knee extensors, knee flexors, and wrist flexors (hand grip), as well as countermovement jumps, at baseline and following exposure to three 12-hour work shifts in a four-day period. Variables included peak torque (PT) and rate of torque development (RTD) from isometric strength testing and jump height and power output. Results The rigorous work period resulted in significant decreases (-7.2% to -19.2%) in a large majority (8/9) of the isometric strength-based measurements. No differences were noted for the day versus night shift workers except for the RTD at 200 millisecond variable, for which the night shift had greater work-induced decreases than the day shift workers. No changes were observed for jump height or power output. Conclusions A compressed nursing work schedule resulted in decreases in strength-based performance abilities, being indicative of performance fatigue. Application Compressed work schedules involving long shifts lead to functional declines in nurse performance capacities that may pose risks for both the nurse and patient quality of care. Fatigue management plans are needed to monitor and regulate increased levels of fatigue.

Third-order-harmonic generation in coherently spinning molecules

NASA Astrophysics Data System (ADS)

Prost, E.; Zhang, H.; Hertz, E.; Billard, F.; Lavorel, B.; Bejot, P.; Zyss, Joseph; Averbukh, Ilya Sh.; Faucher, O.

2017-10-01

The rotational Doppler effect occurs when circularly polarized light interacts with a rotating anisotropic material. It is manifested by the appearance of a spectral shift ensuing from the transfer of angular momentum and energy between radiation and matter. Recently, we reported terahertz-range rotational Doppler shifts produced in third-order nonlinear optical conversion [O. Faucher et al., Phys. Rev. A 94, 051402(R) (2016), 10.1103/PhysRevA.94.051402]. The experiment was performed in an ensemble of coherently spinning molecules prepared by a short laser pulse exhibiting a twisted linear polarization. The present work provides an extensive analysis of the rotational Doppler effect in third-order-harmonic generation from spinning linear molecules. The underlying physics is investigated both experimentally and theoretically. The implication of the rotational Doppler effect in higher-order processes like high-order-harmonic generation is discussed.

Shiftwork and metabolic dysfunction.

PubMed

Tucker, Philip; Marquié, Jean-Claude; Folkard, Simon; Ansiau, David; Esquirol, Yolande

2012-06-01

Many of the health problems that are more prevalent among shiftworkers are thought to be linked to their heightened susceptibility to metabolic syndrome, i.e., the association of even moderate degrees of visceral obesity, dyslipidemia, abnormal blood pressure, and serum glucose levels in the same individual. Although previous studies have identified associations between shiftwork and metabolic syndrome, there is relatively little evidence to date of how the risk of developing it varies as a function of exposure to shiftwork. The current study seeks to confirm earlier findings of an association between shiftwork exposure and metabolic dysfunction, and to examine the impact of exposure duration, while adjusting for a number of covariates in the analyses. The analyses were based on data from VISAT, a study involving the measurement of physiological, behavioral, and subjective outcomes from 1757 participants, 989 being current or former shiftworkers. The sample comprised employed and retired wage earners, male and female, who were 32, 42, 52, and 62 yrs old. The first analysis sought to confirm previous findings of an association between exposure to shiftwork and the risk of developing metabolic syndrome. It indicated that participants who were or who had previously been shiftworkers (i.e., working schedules that involved rotating shifts; not being able to go to bed before midnight; having to get up before 05:00 h; or being prevented from sleeping during the night) were more likely to exhibit symptoms of metabolic syndrome, after adjusting for age, sex, socioeconomic status, smoking, alcohol intake, perceived stress, and sleep difficulty (odds ratio [OR] 1.78; 95% confidence interval [CI] 1.03-3.08). The results suggest the association between shiftwork and metabolic syndrome cannot be fully accounted for by either higher levels of strain or increased sleep difficulty among shiftworkers, although it remains a possibility that either one or both of these factors may have played a contributing role. The second analysis addressed the issue of duration of exposure to shiftwork. Participants with >10 yrs' experience of working rotating shifts were more likely to exhibit symptoms of metabolic syndrome than participants without exposure to shiftwork, i.e., dayworkers, even after adjusting for age and sex (OR 1.96; 95% CI 1.03-3.75). Thus, the current study confirms the association between shiftwork exposure and metabolic syndrome. It also provides new information regarding the time course of the development of the illness as function of exposure duration, although this was only examined in relation to rotating shiftwork. It is concluded that those responsible for monitoring workers' health should pay particular attention to indices of metabolic dysfunction in workers who have been exposed to shiftwork for >10 yrs.

Review of Professional Workers' Multicultural Competence: Implications in Korea

ERIC Educational Resources Information Center

Lee, Romee; Heo, Gyeong Mi; Kim, Jinhee

2016-01-01

The importance of professional workers' multicultural competence (MC) is increasingly noted in Korea, which is shifting into a multicultural society. This study investigates the current location of the discussion regarding the MC of professional workers in Korea using reviews of existing studies in international and Korean contexts. This paper…

Training Child Welfare Workers from an Intersectional Cultural Humility Perspective: A Paradigm Shift

ERIC Educational Resources Information Center

Ortega, Robert M.; Faller, Kathleen Coulborn

2011-01-01

The increasing diversity of the populations encountered and served by child welfare workers challenges cultural competence models. Current concerns focus on the unintentional over-emphasis on shared group characteristics, undervaluing unique differences of individuals served, and privileging worker expertise about the client's culture, thereby…

Changing Times: Understanding Social Workers' Motivation To Be Field Instructors.

ERIC Educational Resources Information Center

Globerman, Judith; Bogo, Marion

2003-01-01

This article reports on social workers' motivations to become field instructors. The findings from qualitative interviews indicate that current organizational culture has a powerful influence on social workers' motivations to volunteer to become field instructors. The implications of this shift are discussed in relation to rejuvenating the…

Empowering Public Welfare Workers through Mutual Support.

ERIC Educational Resources Information Center

Sherman, Wendy Ruth; Wenocur, Stanley

1983-01-01

Examines the organizational binds facing social workers concerned with the provision of services to clients in times of fiscal restraint. Suggests a mutual support group as a step toward empowerment. Workers may shift from a support group to a coalition for action as change agents within institutional settings. (JAC)

After-shift Musculoskeletal Disorder Symptoms in Female Workers and Work-related Factors: A Cross-sectional Study in a Seafood Processing Factory in Vietnam.

PubMed

Tran, Thuy Thi Thu; Phan, Chinh Thi Thuy; Pham, Tuan Cong; Nguyen, Quynh Thuy

2016-01-01

The seafood processing industry has been developing and providing marked contribution to Vietnam's economic growth in recent years. However, information on working conditions and their impacts to workers' health in this sector, focusing on musculoskeletal problems in female workers, has been poorly documented. This paper examines the prevalence of after-shift musculoskeletal disorder symptoms (A-MSDS) and work-related factors in female workers in a seafood processing factory in Vietnam. As part of a comprehensive study, a cross-sectional survey was implemented in one seafood processing factory in the center of Vietnam in 2014. A self-administered questionnaire was completed by 394 female workers to collect information about their A-MSDS state, demographic characteristics, health status and work conditions. Descriptive analysis and logistic regression were applied to describe and analyse the results. Nearly four-fifths of female workers experienced MSDs in at least one body part (77.7%) and 20.1% of them had MSDs in all investigated regions. The prevalence of A-MSDS in different body parts markedly varied, with the proportion of pain in the hips and lower extremities being as high as 53.3%, followed by pain in the shoulders and upper extremities (42.6%) and the neck (41.1%). A humid working environment, exposure to vibration and chemicals as well as taxing task demands and work organizations were found to significantly contribute to the increased risk of after-shift musculoskeletal disorders in female workers. Approximately 80% of female workers in the seafood processing factory experienced musculoskeletal pains after work, especially in the hips, extremities, neck and shoulders which were contributed by work conditions and task demands.

Work Intensity, Low-Grade Inflammation, and Oxidative Status: A Comparison between Office and Slaughterhouse Workers.

PubMed

Zelzer, Sieglinde; Tatzber, Franz; Herrmann, Markus; Wonisch, Willibald; Rinnerhofer, Stefan; Kundi, Michael; Obermayer-Pietsch, Barbara; Niedrist, Tobias; Cvirn, Gerhard; Wultsch, Georg; Mangge, Harald

2018-01-01

Limited knowledge exists about the impact of physical workload on oxidative stress in different occupational categories. Thus, we aimed to investigate the oxidative and inflammatory status in employees with different physical workloads. We enrolled a total of 79 male subjects, 27 office workers (mean age 38.8 ± 9.1 years) and 52 heavy workers, in a slaughterhouse (mean age 40.8 ± 8.2 years). Fasting blood was drawn from an antecubital vein in the morning of the midweek before an 8-hour or 12-hour work shift. The antioxidative capacity was assessed measuring total antioxidant capacity (TAC), uric acid, total polyphenols (PPm), and endogenous peroxidase activity (EPA). Total peroxides (TOC), malondialdehyde (MDA), and myeloperoxidase (MPO) were analyzed as prooxidative biomarkers, and an oxidative stress index (OSI) was calculated. In addition, hsCRP, interleukin-6 (IL-6), MDA-LDL IgM antibodies, galectin-3, adrenocorticotropic hormone (ACTH), and the brain-derived neurotrophic factor (BDNF) were measured as biomarkers of chronic systemic inflammation and emotional stress. TOC ( p = 0.032), TAC ( p < 0.001), ACTH ( p < 0.001), OSI ( p = 0.011), and hsCRP ( p = 0.019) were significantly increased in the heavy workers group, while EPA, BDNF ( p < 0.001), and polyphenols ( p = 0.004) were significantly higher in office workers. Comparison between 8 and 12 h shifts showed a worse psychological condition in heavy workers with increased levels for hsCRP ( p = 0.001) and reduced concentration of BDNF ( p = 0.012) compared to office workers. Oxidative stress and inflammation are induced in heavy workers and are particularly pronounced during long working hours, that is, 12-hour versus 8-hour shifts.

After-shift Musculoskeletal Disorder Symptoms in Female Workers and Work-related Factors: A Cross-sectional Study in a Seafood Processing Factory in Vietnam

PubMed Central

Tran, Thuy Thi Thu; Phan, Chinh Thi Thuy; Pham, Tuan Cong; Nguyen, Quynh Thuy

2016-01-01

Background The seafood processing industry has been developing and providing marked contribution to Vietnam's economic growth in recent years. However, information on working conditions and their impacts to workers' health in this sector, focusing on musculoskeletal problems in female workers, has been poorly documented. Objectives This paper examines the prevalence of after-shift musculoskeletal disorder symptoms (A-MSDS) and work-related factors in female workers in a seafood processing factory in Vietnam. Materials and Methods As part of a comprehensive study, a cross-sectional survey was implemented in one seafood processing factory in the center of Vietnam in 2014. A self-administered questionnaire was completed by 394 female workers to collect information about their A-MSDS state, demographic characteristics, health status and work conditions. Descriptive analysis and logistic regression were applied to describe and analyse the results. Results Nearly four-fifths of female workers experienced MSDs in at least one body part (77.7%) and 20.1% of them had MSDs in all investigated regions. The prevalence of A-MSDS in different body parts markedly varied, with the proportion of pain in the hips and lower extremities being as high as 53.3%, followed by pain in the shoulders and upper extremities (42.6%) and the neck (41.1%). A humid working environment, exposure to vibration and chemicals as well as taxing task demands and work organizations were found to significantly contribute to the increased risk of after-shift musculoskeletal disorders in female workers. Conclusion Approximately 80% of female workers in the seafood processing factory experienced musculoskeletal pains after work, especially in the hips, extremities, neck and shoulders which were contributed by work conditions and task demands. PMID:29546192

Geometry of tracer trajectories in rotating turbulent flows

NASA Astrophysics Data System (ADS)

Alards, Kim M. J.; Rajaei, Hadi; Del Castello, Lorenzo; Kunnen, Rudie P. J.; Toschi, Federico; Clercx, Herman J. H.

2017-04-01

The geometry of passive tracer trajectories is studied in two different types of rotating turbulent flows; rotating Rayleigh-Bénard convection (RBC; experiments and direct numerical simulations) and rotating electromagnetically forced turbulence (EFT; experiments). This geometry is fully described by the curvature and torsion of trajectories, and from these geometrical quantities we can subtract information on the typical flow structures at different rotation rates. Previous studies, focusing on nonrotating homogeneous isotropic turbulence (HIT), show that the probability density functions (PDFs) of curvature and torsion reveal pronounced power laws. However, the set-ups studied here involve inhomogeneous turbulence, and in RBC the flow near the horizontal plates is definitely anisotropic. We investigate how the typical shapes of the curvature and torsion PDFs, including the pronounced scaling laws, are influenced by this level of anisotropy and inhomogeneity and how this effect changes with rotation. A first effect of rotation is observed as a shift of the curvature and torsion PDFs towards higher values in the case of RBC and towards lower values in the case of EFT. This shift is related to the length scale of typical vortical structures that decreases with rotation in RBC, but increases with rotation in EFT, explaining the opposite shifts of the curvature (and torsion) PDFs. A second remarkable observation is that in RBC the HIT scaling laws are always recovered, as long as the boundary layer (BL) is excluded. This suggests that these scaling laws are very robust and hold as long as we measure in the turbulent bulk. In the BL of the RBC cell, however, the scaling deviates from the HIT prediction for lower rotation rates. This scaling behavior is found to be consistent with the coupling between the boundary layer dynamics and the bulk flow, which changes under rotation. In particular, it is found that the active coupling of the Ekman-type boundary layer with the bulk flow suppresses anisotropy in the BL region for increasing rotation rates.

Armodafinil for treatment of excessive sleepiness associated with shift work disorder: a randomized controlled study.

PubMed

Czeisler, Charles A; Walsh, James K; Wesnes, Keith A; Arora, Sanjay; Roth, Thomas

2009-11-01

To assess the effect of armodafinil, 150 mg, on the physiologic propensity for sleep and cognitive performance during usual night shift hours in patients with excessive sleepiness associated with chronic (> or =3 months) shift work disorder (SWD) of moderate or greater severity. This 12-week, randomized controlled study was conducted at 42 sleep research facilities in North America from April 2 through December 23, 2004, and enrolled 254 permanent or rotating night shift workers with SWD. Entry criteria included excessive sleepiness during usual night shifts for 3 months or longer (corroborated by mean sleep latency of < or =6 minutes on a Multiple Sleep Latency Test), insomnia (sleep efficiency < or =87.5% during daytime sleep), and SWD that was judged clinically to be of moderate or greater severity. Patients received armodafinil, 150 mg, or placebo 30 to 60 minutes before each night shift. Physiologic sleep propensity during night shift hours, clinical impression of severity, patient-reported sleepiness, and cognitive function were assessed during laboratory night shifts at weeks 4, 8, and 12. Armodafinil significantly improved mean (SD) sleep latency from 2.3 (1.6) minutes at baseline to 5.3 (5.0) minutes at final visit, compared with a change from 2.4 (1.6) minutes to 2.8 (2.9) minutes in the placebo group (P<.001). Clinical condition ratings improved in more patients receiving armodafinil (79%) vs placebo (59%) (P=.001). As reported by patients' diaries, armodafinil significantly reduced sleepiness during laboratory nights (P<.001), night shifts at work (P<.001), and the commute home (P=.003). Armodafinil improved performance on standardized memory (P<.001) and attention (power, P=.001; continuity, P<.001) tests compared with placebo. Armodafinil was well tolerated and did not affect daytime sleep, as measured by polysomnography. In patients with excessive sleepiness associated with chronic SWD of moderate or greater severity, armodafinil significantly improved wakefulness during scheduled night work, raising mean nighttime sleep latency above the level considered to indicate severe sleepiness during the daytime. Armodafinil also significantly improved measures of overall clinical condition, long-term memory, and attention. clinicaltrials.gov Identifier: NCT00080288.

Managing ergonomics in the development of rotation between workstations in the automotive industry. A balance between health and traceability of tasks.

PubMed

Filus, Rodrigo; Partel, Luciana

2012-01-01

Abstract When the subject rotation between workstations (job rotation) is inside the organizations it's seemed that technically there are lots of restrictions to the development of an adequate system of rotation. We went from the need for an advanced ergonomic study and even possible restrictions of versatility and training of employees. The implementation of the ideal system of rotation passes through stages of development and research ergonomic study of the level of employee versatility, awareness and discussion with employees, implementation of the proposed system, feedback and audits for maintenance of the ideal sequence and time of rotation. For the success of the project there is a need for multidisciplinary involvement in the areas of manufacturing engineering, industrial engineering, human resources, medical services and manufacturing. Rotation between the tasks may mean that a worker should conduct two or more different activities in different parts of the day (ie. change between activity A and activity B "between 1 hours and 2 hours interval). An important consideration is to ensure that different activities do not present the same ergonomic risk for the same body part. The tracing of the execution of the activity is an important factor for production processes. Thus it is possible to conduct appropriate levels of training for employees and ensure safe and sustainable processes in terms of workers' health, productivity and quality.

Job rotation designed to prevent musculoskeletal disorders and control risk in manufacturing industries: A systematic review.

PubMed

Padula, Rosimeire Simprini; Comper, Maria Luiza Caires; Sparer, Emily H; Dennerlein, Jack T

2017-01-01

To better understand job rotation in the manufacturing industry, we completed a systematic review asking the following questions: 1) How do job-rotation programs impact work-related musculoskeletal disorders (MSDs) and related risk control for these MSDs, as well as psychosocial factors? and 2) How best should the job rotation programs be designed? We searched MEDLINE, EMBASE, Business Source Premier, ISI Web of Knowledge, CINAHL, PsyINFO, Scopus, and SciELO databases for articles published in peer-reviewed journals. Eligible studies were examined by two independent reviewers for relevance (population of manufacturing workers, outcomes of musculoskeletal disorders, physical factors, psychosocial factors, and strategies used in job-rotation implantation) and methodological quality rating. From 10,809 potential articles, 71 were read for full text analysis. Of the 14 studies included for data extraction, two were non-randomized control trial studies, one was a case-control study, and 11 were cross-sectional comparisons. Only one, with a case-control design, was scored with good methodological quality. Currently, weak evidence exists supporting job rotation as a strategy for the prevention and control of musculoskeletal disorders. Job rotation did not appear to reduce the exposure of physical risk factors; yet, there are positive correlations between job rotation and higher job satisfaction. Worker training has been described as a crucial component of a successful job-rotation program. The studies reported a range of parameters used to implement and measure job-rotation programs. More rigorous studies are needed to better understand the full impact of job rotation on production and health. CRD42014013319. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparative Study of Job Burnout Among Critical Care Nurses With Fixed and Rotating Shift Schedules

PubMed Central

Shamali, Mahdi; Shahriari, Mohsen; Babaii, Atye; Abbasinia, Mohammad

2015-01-01

Background: Nurses, as health care providers, are insurmountably obliged to the practice of shift work. Literature has reported shift working as one of the inducing factors of burnout. Despite numerous studies in this area, there are inconsistencies on the relationship between shift working and burnout among nurses, especially in those who work in critical care settings. Objectives: The aim of this study was to compare the occupational burnout in critical care nurses with and without fixed shift schedules. Patients and Methods: In this comparative study, 130 nurses with rotating shift schedule and 130 nurses with fixed shift schedule from six university hospitals were selected using stratified random sampling. Maslach burnout inventory was used for data collection. Independent samples t-test, chi-square and one-way ANOVA tests were used to analyze the data. Results: Most of the participants were females (62.7%), aged between 22 - 29 years (38.5%), married (59.2%), and had a bachelor degree (86.9%). The mean score of emotional exhaustion was significantly higher in nurses with fixed shift schedules (P < 0.001). However, no significant difference was found between the mean scores of the two groups in the personal accomplishment and depersonalization subscales (P > 0.05). Moreover, no significant difference was found in burnout mean scores between nurses with fixed morning and fixed night shifts (P > 0.05). The means of the emotional exhaustion subscale were significantly different in nurses with different characteristics (P < 0.05) except the gender and working unit. Conclusions: As a result of this study, it was found that critical care nurses with fixed shift schedules display more burnout in emotional exhaustion dimension, compared to those working with rotating shift schedules. PMID:26576442

Geometry of tracer trajectories in turbulent rotating convection

NASA Astrophysics Data System (ADS)

Alards, Kim; Rajaei, Hadi; Kunnen, Rudie; Toschi, Federico; Clercx, Herman

2016-11-01

In Rayleigh-Bénard convection rotation is known to cause transitions in flow structures and to change the level of anisotropy close to the horizontal plates. To analyze this effect of rotation, we collect curvature and torsion statistics of passive tracer trajectories in rotating Rayleigh-Bénard convection, using both experiments and direct numerical simulations. In previous studies, focusing on homogeneous isotropic turbulence (HIT), curvature and torsion PDFs are found to reveal pronounced power laws. In the center of the convection cell, where the flow is closest to HIT, we recover these power laws, regardless of the rotation rate. However, near the top plate, where we expect the flow to be anisotropic, the scaling of the PDFs deviates from the HIT prediction for lower rotation rates. This indicates that anisotropy clearly affects the geometry of tracer trajectories. Another effect of rotation is observed as a shift of curvature and torsion PDFs towards higher values. We expect this shift to be related to the length scale of typical flow structures. Using curvature and torsion statistics, we can characterize how these typical length scales evolve under rotation and moreover analyze the effect of rotation on more complicated flow characteristics, such as anisotropy.

Bloch-Siegert shift in an interacting Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

Zhang, Jinyi; Eigen, Christoph; Lopes, Raphael; Garratt, Sam; Rousso, David; Smith, Robert P.; Hadzibabic, Zoran; Navon, Nir

2017-04-01

The Bloch-Siegert shift (BSS) is a paradigmatic frequency shift that arises from the nonlinear response of a two-level system (TLS) subjected to strong driving fields. When a TLS is driven by a linearly polarized field, the co-rotating-wave component leads to the famous Rabi oscillations. By contrast the co-rotating-wave component, whose role is usually neglected in a weak driving, leads to a frequency shift of the TLS resonance frequency. This phenomenon is encountered in various areas, from quantum optics to nuclear magnetic resonance.Here, we investigate the BSS in a box-trapped 87 Rb Bose-Einstein condensate (BEC) driven by a strong oscillating magnetic field gradient. By tuning the chemical potential of the gas, we investigate how the BSS evolves from the ideal shift of the two lowest energy levels of a single particle in a box to the unexplored shift of long-wavelength collective excitations of the interacting BEC.

Shift and rotation invariant photorefractive crystal-based associative memory

NASA Astrophysics Data System (ADS)

Uang, Chii-Maw; Lin, Wei-Feng; Lu, Ming-Huei; Lu, Guowen; Lu, Mingzhe

1995-08-01

A shift and rotation invariant photorefractive (PR) crystal based associative memory is addressed. The proposed associative memory has three layers: the feature extraction, inner- product, and output mapping layers. The feature extraction is performed by expanding an input object into a set of circular harmonic expansions (CHE) in the Fourier domain to acquire both the shift and rotation invariant properties. The inner product operation is performed by taking the advantage of Bragg diffraction of the bulky PR-crystal. The output mapping is achieved by using the massive storage capacity of the PR-crystal. In the training process, memories are stored in another PR-crystal by using the wavelength multiplexing technique. During the recall process, the output from the winner-take-all processor decides which wavelength should be used to read out the memory from the PR-crystal.

Knowledge-based support for the participatory design and implementation of shift systems.

PubMed

Gissel, A; Knauth, P

1998-01-01

This study developed a knowledge-based software system to support the participatory design and implementation of shift systems as a joint planning process including shift workers, the workers' committee, and management. The system was developed using a model-based approach. During the 1st phase, group discussions were repeatedly conducted with 2 experts. Thereafter a structure model of the process was generated and subsequently refined by the experts in additional semistructured interviews. Next, a factual knowledge base of 1713 relevant studies was collected on the effects of shift work. Finally, a prototype of the knowledge-based system was tested on 12 case studies. During the first 2 phases of the system, important basic information about the tasks to be carried out is provided for the user. During the 3rd phase this approach uses the problem-solving method of case-based reasoning to determine a shift rota which has already proved successful in other applications. It can then be modified in the 4th phase according to the shift workers' preferences. The last 2 phases support the final testing and evaluation of the system. The application of this system has shown that it is possible to obtain shift rotas suitable to actual problems and representative of good ergonomic solutions. A knowledge-based approach seems to provide valuable support for the complex task of designing and implementing a new shift system. The separation of the task into several phases, the provision of information at all stages, and the integration of all parties concerned seem to be essential factors for the success of the application.

Occupational Noise Exposure of Employees at Locally-Owned Restaurants in a College Town

PubMed Central

Green, Deirdre R.; Anthony, T. Renée

2016-01-01

While many restaurant employees work in loud environments, in both dining and food preparation areas, little is known about worker exposures to noise. The risk of hearing loss to millions of food service workers around the country is unknown. This study evaluated full-shift noise exposure to workers at six locally-owned restaurants to examine risk factors associated with noise exposures during the day shift. Participants included cooks, counter attendants, bartenders, and waiters at full-service restaurants with bar service and at limited-service restaurants that provided counter service only. Assessments were made on weekdays and weekends, both during the summer and the fall (with a local university in session) to examine whether the time of week or year affects noise exposures to this population in a college town. In addition, the relationships between noise exposures and the type of restaurant and job classification were assessed. One-hundred eighty full-shift time-weighted average (TWA) exposures were assessed, using both Occupational Safety and Health Administration (OSHA) and National Institute for Occupational Safety and Health (NIOSH) criteria. No TWA measurements exceeded the 90 dBA OSHA 8 hr permissible exposure limit, although six projected TWAs exceeded the 85 dBA OSHA hearing conservation action limit. Using NIOSH criteria, TWAs ranged from 69–90 dBA with a mean of 80 dBA (SD = 4 dBA). Nearly 8% (14) of the exposures exceeded the NIOSH 8-hr 85 dBA. Full-shift exposures were larger for all workers in full-service restaurants (p < 0.001) and for cooks (p = 0.003), regardless of restaurant type. The fall semester (p = 0.003) and weekend (p = 0.048) exposures were louder than summer and weekdays. Multiple linear regression analysis suggested that the combination of restaurant type, job classification, and season had a significant effect on restaurant worker noise exposures (p < 0.001) in this college town. While evening/night shift exposures, where noise exposures may be anticipated to be louder, were not assessed, this study identified that restaurant type, job classification, time of week, and season significantly affected the noise exposures for day-shift workers. Intervention studies to prevent noise-induced hearing loss (NIHL) should consider these variables. PMID:25738733

Occupational Noise Exposure of Employees at Locally-Owned Restaurants in a College Town.

PubMed

Green, Deirdre R; Anthony, T Renée

2015-01-01

While many restaurant employees work in loud environments, in both dining and food preparation areas, little is known about worker exposures to noise. The risk of hearing loss to millions of food service workers around the country is unknown. This study evaluated full-shift noise exposure to workers at six locally-owned restaurants to examine risk factors associated with noise exposures during the day shift. Participants included cooks, counter attendants, bartenders, and waiters at full-service restaurants with bar service and at limited-service restaurants that provided counter service only. Assessments were made on weekdays and weekends, both during the summer and the fall (with a local university in session) to examine whether the time of week or year affects noise exposures to this population in a college town. In addition, the relationships between noise exposures and the type of restaurant and job classification were assessed. One-hundred eighty full-shift time-weighted average (TWA) exposures were assessed, using both Occupational Safety and Health Administration (OSHA) and National Institute for Occupational Safety and Health (NIOSH) criteria. No TWA measurements exceeded the 90 dBA OSHA 8 hr permissible exposure limit, although six projected TWAs exceeded the 85 dBA OSHA hearing conservation action limit. Using NIOSH criteria, TWAs ranged from 69-90 dBA with a mean of 80 dBA (SD = 4 dBA). Nearly 8% (14) of the exposures exceeded the NIOSH 8-hr 85 dBA. Full-shift exposures were larger for all workers in full-service restaurants (p < 0.001) and for cooks (p = 0.003), regardless of restaurant type. The fall semester (p = 0.003) and weekend (p = 0.048) exposures were louder than summer and weekdays. Multiple linear regression analysis suggested that the combination of restaurant type, job classification, and season had a significant effect on restaurant worker noise exposures (p < 0.001) in this college town. While evening/night shift exposures, where noise exposures may be anticipated to be louder, were not assessed, this study identified that restaurant type, job classification, time of week, and season significantly affected the noise exposures for day-shift workers. Intervention studies to prevent noise-induced hearing loss (NIHL) should consider these variables.

A new typology of work schedules: Evidence from a cross-sectional study among nurses working in residential elder care.

PubMed

Peters, V; de Rijk, A; Engels, J; Heerkens, Y; Nijhuis, F

2016-04-07

Work schedules contribute substantially to the health and well-being of nurses. Too broad typologies are used in research that do not meet the current variety in work schedules. To develop a new typology for nurses' work schedules based on five requirements and to validate the typology. This study is based on a questionnaire returned by 498 nurses (response 51%) including questions regarding nurses' work schedule, socio-demographic, and family characteristics and their appraisal of the work schedule. Frequencies of the different schedules were computed to determine the typology. To validate the typology, differences between the types were tested with ANOVAs, Chi2 and Kruskal-Wallis tests. Five main types can be distinguished based on predetermined requirements and frequencies, namely: (1) fixed early shift, (2) rotating two shift pattern without night shift, (3) rotating three shift pattern, (4) fixed and rotating two shift pattern including night shift, and (5) fixed normal day or afternoon shifts. Nurses in these types of work schedule differed significantly with respect to hours worked, days off between shifts, age, education, years in the job, commuting time, contribution to household income, satisfaction with work schedule and work schedule control. Especially nurses with type 3 schedules differed from other types. A typology of five main types of work schedules is proposed. Content validity of the typology is sufficient and the new typology seems useful for research on work-related aspects of nursing.

Effects of Fatigue on Driving Safety: A Comparison of Brake Reaction Times in Night Float and Postcall Physicians in Training

PubMed Central

Talusan, Paul G.; Long, Theodore; Halim, Andrea; Guliani, Laura; Carroll, Nicole; Reach, John

2014-01-01

Background Concerns about duty hour and resident safety have fostered discussion about postshift fatigue and driving impairment. Objective We assessed how converting to a night float schedule for overnight coverage affected driving safety for trainees. Methods Brake reaction times were measured for internal medicine and orthopaedic surgery resident volunteers after a traditional 28-hour call shift and after a night float shift. We conducted matched paired t tests of preshift and postshift reaction time means. Participants also completed the Epworth Sleepiness Scale pre- and postshift. Results From June to July 2013, we enrolled 58 interns and residents (28 orthopaedic surgery, 30 internal medicine). We included 24 (41%) trainees on night float rotations and 34 (59%) trainees on traditional 28-hour call shifts. For all residents on night float rotations, there was no significant difference pre- and postshift. An increase in reaction times was noted among trainees on 28-hour call rotations. This included no effect on reaction times for internal medicine trainees pre- and postshift, and an increase in reaction times for orthopaedic trainees. For both night float and traditional call groups, there were significant increases in the Epworth Sleepiness Scale. Conclusions Trainees on traditional 28-hour call rotations had significantly worse postshift brake reaction times, whereas trainees on night float rotations had no difference. Orthopaedic trainees had significant differences in brake reaction times after a traditional call shift. PMID:26140113

Associations among rotating night shift work, sleep and skin cancer in Nurses' Health Study II participants.

PubMed

Heckman, Carolyn J; Kloss, Jacqueline D; Feskanich, Diane; Culnan, Elizabeth; Schernhammer, Eva S

2017-03-01

Night shift work and sleep duration have been associated with breast and other cancers. Results from the few prior studies of night shift work and skin cancer risk have been mixed and not fully accounted for other potentially important health-related variables (eg, sleep characteristics). This study evaluated the relationship between rotating night shift work and skin cancer risk and included additional skin cancer risk factors and sleep-related variables. The current study used data from 74 323 Nurses' Health Study (NHS) II participants. Cox proportional hazards models were used to estimate multivariable-adjusted HRs and 95% CIs for skin cancers across categories of shift work and sleep duration. Over 10 years of follow-up, 4308 basal cell carcinoma (BCC), 334 squamous cell carcinoma (SCC) and 212 melanoma cases were identified. Longer duration of rotating night shifts was associated with a linear decline in risk of BCC (HR=0.93, 95% CI 0.90 to 0.97 per 5-year increase). Shift work was not significantly associated with either melanoma (HR=1.02, 95% CI 0.86 to 1.21) or SCC (HR=0.92, 95% CI 0.80 to 1.06). A short sleep duration (≤6 hours per day) was associated with lower risks of melanoma (HR=0.68, 95% CI 0.46 to 0.98) and BCC (HR=0.93, 95% CI 0.86 to 1.00) compared with the most common report of 7 hours. SCC was not associated with duration of sleep (HR=0.94, 95% CI 0.83 to 1.06). Longer duration of rotating night shift work and shorter sleep duration were associated with lower risk of some skin cancers. Further research is needed to confirm and identify the mechanisms underlying these associations. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Night shift work at specific age ranges and chronic disease risk factors.

PubMed

Ramin, Cody; Devore, Elizabeth E; Wang, Weike; Pierre-Paul, Jeffrey; Wegrzyn, Lani R; Schernhammer, Eva S

2015-02-01

We examined the association of night shift work history and age when night shift work was performed with cancer and cardiovascular disease risk factors among 54 724 women in the Nurses' Health Study (NHS) II. We calculated age-adjusted and socioeconomic status-adjusted means and percentages for cancer and cardiovascular risk factors in 2009 across categories of night shift work history. We used multivariable-adjusted logistic regression to estimate odds ratios (ORs) and 95% CIs for key risk factors among 54 724 participants (72% ever shift workers). We further examined these associations by age (20-25, 26-35, 36-45 and 46+ years) at which shift work was performed. Ever night shift workers had increased odds of obesity (body mass index ≥30 kg/m(2); OR=1.37, 95% CI 1.31 to 1.43); higher caffeine intake (≥131 mg/day; OR=1.16, 95% CI 1.12 to 1.22) and total calorie intake (≥1715 kcal/day; OR=1.09, 95% CI 1.04 to 1.13); current smoking (OR=1.30, 95% CI 1.19 to 1.42); and shorter sleep durations (≤7 h of sleep/day; OR=1.19, 95% CI 1.15 to 1.24) compared to never night shift workers. These estimates varied depending on age at which night work was performed, with a suggestion that night shift work before age 25 was associated with fewer risk factors compared to night shift work at older ages. Our results indicate that night shift work may contribute to an adverse chronic disease risk profile, and that risk factors may vary depending on the age at which night shift work was performed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Excessive sleepiness and self-reported shift work disorder: an Internet survey of shift workers.

PubMed

Lieberman, Joseph A; Sylvester, Lauren; Paik, Sharon

2013-05-01

To compare excessive sleepiness and quality of life (QoL) scores in shift workers who report having a diagnosis of shift work disorder (SWD) with those who report having no such diagnosis. An Internet-based survey was conducted between March and April 2009 that included shift workers with or without a self-reported diagnosis of SWD. Participation required working ≥ 21 hours/week for 2 weeks prior, a diagnosis of SWD or a score of ≥ 10 on the Epworth Sleepiness Scale, and a score of ≥ 5 on any subscale of the Sheehan Disability Scale. Surveys included 260 shift workers (103 with an SWD diagnosis and 157 without an SWD diagnosis). Diagnosed and undiagnosed respondents demonstrated similar Epworth Sleepiness Scale (13.7 vs 13.6, respectively) and Karolinska Sleepiness Scale (6.0 vs 5.5, respectively) scores. Sheehan Disability Scale social life and family life scores were similar between the 2 groups, although diagnosed respondents had a greater mean Sheehan Disability Scale work disability score compared with undiagnosed respondents (6.7 vs 5.5; P < 0.0001). Quality of life was more impaired in diagnosed patients in terms of ability to drive safely, propensity for accidents, work performance, and anxiety (P ≤ 0.039 vs undiagnosed). Work-related accidents (16% vs 5%; P = 0.0076) and injuries at work (17% vs 7%; P = 0.0233) were also reported by more diagnosed respondents than by undiagnosed respondents. Many respondents used caffeine and 57% of diagnosed respondents received prescription medication to treat symptoms of SWD. Individuals with diagnosed SWD demonstrated impairment in QoL and reported more work-related accidents and injuries, although many measures of QoL and prescription drug use were similar between groups. Shift work disorder is underrecognized by clinicians and patients, resulting in undertreatment, despite the availability of several behavioral and therapeutic treatment options.

The Differential Effects of Regular Shift Work and Obstructive Sleep Apnea on Sleepiness, Mood and Neurocognitive Function.

PubMed

Cori, Jennifer M; Jackson, Melinda L; Barnes, Maree; Westlake, Justine; Emerson, Paul; Lee, Jacen; Galante, Rosa; Hayley, Amie; Wilsmore, Nicholas; Kennedy, Gerard A; Howard, Mark

2018-06-15

To assess whether poor sleep quality experienced by regular shift workers and individuals with obstructive sleep apnea (OSA) affects neurobehavioral function similarly, or whether the different etiologies have distinct patterns of impairment. Thirty-seven shift workers (> 24 hours after their last shift), 36 untreated patients with OSA, and 39 healthy controls underwent assessment of sleepiness (Epworth Sleepiness Scale [ESS]), mood (Beck Depression Index, State Trait Anxiety Inventory [STAI], Profile of Mood States), vigilance (Psychomotor Vigilance Task [PVT], Oxford Sleep Resistance Test [OSLER], driving simulation), neurocognitive function (Logical Memory, Trails Making Task, Digit Span Task, Victoria Stroop Test) and polysomnography. Sleepiness (ESS score; median, interquartile range) did not differ between the OSA (10.5, 6.3-14) and shift work (7, 5-11.5) groups, but both had significantly elevated scores relative to the control group (5, 3-6). State anxiety (STAI-S) was the only mood variable that differed significantly between the OSA (35, 29-43) and shift work (30, 24-33.5) groups, however both demonstrated several mood deficits relative to the control group. The shift work and control groups performed similarly on neurobehavioral tasks (simulated driving, PVT, OSLER and neurocognitive tests), whereas the OSA group performed worse. On the PVT, lapses were significantly greater for the OSA group (3, 2-6) than both the shift work (2, 0-3.5) and control (1, 0-4) groups. Shift workers and patients with OSA had similar sleepiness and mood deficits relative to healthy individuals. However, only the patients with OSA showed deficits on vigilance and neurocognitive function relative to healthy individuals. These findings suggest that distinct causes of sleep disturbance likely result in different patterns of neurobehavioral dysfunction. © 2018 American Academy of Sleep Medicine.

Heat stress, dehydration, and kidney function in sugarcane cutters in El Salvador--A cross-shift study of workers at risk of Mesoamerican nephropathy.

PubMed

García-Trabanino, Ramón; Jarquín, Emmanuel; Wesseling, Catharina; Johnson, Richard J; González-Quiroz, Marvin; Weiss, Ilana; Glaser, Jason; José Vindell, Juan; Stockfelt, Leo; Roncal, Carlos; Harra, Tamara; Barregard, Lars

2015-10-01

An epidemic of progressive kidney failure afflicts sugarcane workers in Central America. Repeated high-intensity work in hot environments is a possible cause. To assess heat stress, dehydration, biomarkers of renal function and their possible associations. A secondary aim was to evaluate the prevalence of pre-shift renal damage and possible causal factors. Sugarcane cutters (N=189, aged 18-49 years, 168 of them male) from three regions in El Salvador were examined before and after shift. Cross-shift changes in markers of dehydration and renal function were examined and associations with temperature, work time, region, and fluid intake were assessed. Pre-shift glomerular filtration rate was estimated (eGFR) from serum creatinine. The mean work-time was 4 (1.4-11) hours. Mean workday temperature was 34-36 °C before noon, and 39-42 °C at noon. The mean liquid intake during work was 0.8L per hour. There were statistically significant changes across shift. The mean urine specific gravity, urine osmolality and creatinine increased, and urinary pH decreased. Serum creatinine, uric acid and urea nitrogen increased, while chloride and potassium decreased. Pre-shift serum uric acid levels were remarkably high and pre-shift eGFR was reduced (<60 mL/min) in 23 male workers (14%). The high prevalence of reduced eGFR, and the cross-shift changes are consistent with recurrent dehydration from strenuous work in a hot and humid environment as an important causal factor. The pathophysiology may include decreased renal blood flow, high demands on tubular reabsorption, and increased levels of uric acid. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Task shifting and sharing in maternal and reproductive health in low-income countries: a narrative synthesis of current evidence.

PubMed

Dawson, Angela J; Buchan, James; Duffield, Christine; Homer, Caroline S E; Wijewardena, Kumudu

2014-05-01

Reducing maternal mortality and providing universal access to reproductive health in resource poor settings has been severely constrained by a shortage of health workers required to deliver interventions. The aim of this article is to determine evidence to optimize health worker roles through task shifting/sharing to address Millennium Development Goal 5 and reduce maternal mortality and provide universal access to reproductive health. A narrative synthesis of peer-reviewed literature from 2000 to 2011 was undertaken with retrieved documents assessed using an inclusion/exclusion criterion and quality appraisal guided by critical assessment tools. Concepts were analysed thematically. The analysis identified a focus on clinical tasks (the delivery of obstetric surgery, anaesthesia and abortion) that were shifted to and/or shared with doctors, non-physician clinicians, nurses and midwives. Findings indicate that shifting and sharing these tasks may increase access to and availability of maternal and reproductive health (MRH) services without compromising performance or patient outcomes and may be cost effective. However, a number of issues and barriers were identified with health workers calling for improved in-service training, supervision, career progression and incentive packages to better support their practice. Collaborative approaches involving community members and health workers at all levels have the potential to deliver MRH interventions effectively if accompanied by ongoing investment in the health care system.

Reducing Risks to Women Linked to Shift Work, Long Work Hours, and Related Workplace Sleep and Fatigue Issues.

PubMed

Caruso, Claire C

2015-10-01

In the United States, an estimated 12% to 28% of working women are on shift work schedules, and 12% work more than 48 hours per week. Shift work and long work hours are associated with many health and safety risks, including obesity, injuries, and negative reproductive outcomes. Over time, the worker is at risk for developing a wide range of chronic diseases. These work schedules can also strain personal relationships, owing to fatigue and poor mood from sleep deprivation and reduced quality time to spend with family and friends. Worker errors from fatigue can lead to reduced quality of goods and services, negatively impacting the employer. In addition, mistakes by fatigued workers can have far-reaching negative effects on the community, ranging from medical care errors to motor vehicle crashes and industrial disasters that endanger others. To reduce the many risks that are linked to these demanding work hours, the National Institute for Occupational Safety and Health (NIOSH) conducts research, develops guidance and authoritative recommendations, and translates and disseminates scientific information to protect workers, their families, employers, and the community. The key message to reduce these risks is making sleep a priority in the employer's systems for organizing work and in the worker's personal life. The NIOSH website has freely available online training programs with suggestions for workers and their managers to help them better cope with this workplace hazard.

Effects of partial circadian adjustments on sleep and vigilance quality during simulated night work.

PubMed

Chapdelaine, Simon; Paquet, Jean; Dumont, Marie

2012-08-01

In most situations, complete circadian adjustment is not recommended for night workers. With complete adjustment, workers experience circadian misalignment when returning on a day-active schedule, causing repeated circadian phase shifts and internal desynchrony. For this reason, partial circadian realignment was proposed as a good compromise to stabilize internal circadian rhythms in night shift workers. However, the extent of partial circadian adjustment necessary to improve sleep and vigilance quality is still a matter of debate. In this study, the effects of small but statistically significant partial circadian adjustments on sleep and vigilance quality were assessed in a laboratory simulation of night work to determine whether they were also of clinical significance. Partial adjustments obtained by phase delay or by phase advance were quantified not only by the phase shift of dim light salivary melatonin onset, but also by the overlap of the episode of melatonin production with the sleep-wake cycle adopted during simulated night work. The effects on daytime sleep and night-time vigilance quality were modest. However, they suggest that even small adjustments by phase delay may decrease the accumulation of sleep debt, whereas the advance strategy improves subjective alertness and mood during night work. Furthermore, absolute phase shifts, by advance or by delay, were associated with improved subjective alertness and mood during the night shift. These strategies need to be tested in the field, to determine whether they can be adapted to real-life situations and provide effective support to night workers. © 2012 European Sleep Research Society.

Nightshift work and genome-wide DNA methylation.

PubMed

Bhatti, Parveen; Zhang, Yuzheng; Song, Xiaoling; Makar, Karen W; Sather, Cassandra L; Kelsey, Karl T; Houseman, E Andres; Wang, Pei

2015-02-01

The negative health effects of shift work, including carcinogenesis, may be mediated by changes in DNA methylation, particularly in the circadian genes. Using the Infinium HumanMethylation450 Bead Array (Illumina, San Diego, CA), we compared genome-wide methylation between 65 actively working dayshift workers and 59 actively working nightshift workers in the healthcare industry. A total of 473 800 loci, including 391 loci across the 12 core circadian genes, were analyzed to identify methylation markers associated with shift work status using linear regression models adjusted for gender, age, body mass index, race, smoking status and leukocyte cell profile as measured by flow cytometry. Analyses at the level of gene, CpG island and gene region were also conducted. To account for multiple comparisons, we controlled the false discovery rate (FDR ≤0.05). Significant differences between nightshift and dayshift workers were found at 16 135 of 473 800 loci, across 3769 of 20 164 genes, across 7173 of 22 721 CpG islands and across 5508 of 51 843 gene regions. For each significant loci, gene, CpG island or gene region, average methylation was consistently found to be decreased among nightshift workers compared to dayshift workers. Twenty-one loci located in the circadian genes were also found to be significantly hypomethylated among nightshift workers. The largest differences were observed for three loci located in the gene body of PER3. A total of nine significant loci were found in the CSNK1E gene, most of which were located in a CpG island and near the transcription start site of the gene. Methylation changes in these circadian genes may lead to altered expression of these genes which has been associated with cancer in previous studies. Gene ontology enrichment analysis revealed that among the significantly hypomethylated genes, processes related to host defense and immunity were represented. Our results indicate that the health effects of shift work may be mediated by hypomethylation of a wide variety of genes, including those related to circadian rhythms. While these findings need to be followed-up among a considerably expanded group of shift workers, the data generated by this study supports the need for future targeted research into the potential impacts of shift work on specific carcinogenic mechanisms.

The Effects of Aromatherapy Massage on Sleep Quality of Nurses on Monthly Rotating Night Shifts

PubMed Central

Lin, Chao-Ling

2017-01-01

The goal of this study is to examine the effects of aromatherapy massage on sleep quality of nurses with monthly rotating night shifts. Subjects were enrolled at a medical center in central Taiwan with overall score ≥ 5 of Pittsburgh Sleep Quality Index (PSQI) and randomly assigned to the treatment or control groups. They were validated by pretests during their first graveyard shift in the trial period and the sleep quality information was collected by using the PSQI and sleep detectors. During the second graveyard shift, the treatment group received aromatherapy massage and the control group rested in the same aromatherapy room after work. All subjects filled out the PSQI surveys and the sleep quality information was collected during massage or resting and the following night. We found that the total PSQI was significantly decreased in the treatment group following the aromatherapy massage. Specifically, the components such as subjective sleep quality, sleep disturbance, and daytime dysfunction were significantly decreased. However, there were no significant changes of average PSQI scores between the two groups before and after intervention. Taken together, our study suggested that aromatherapy massage could improve sleep quality of nurses with monthly rotating night shift. PMID:28761497

The Effects of Aromatherapy Massage on Sleep Quality of Nurses on Monthly Rotating Night Shifts.

PubMed

Chang, Ying-Ying; Lin, Chao-Ling; Chang, Li-Yin

2017-01-01

The goal of this study is to examine the effects of aromatherapy massage on sleep quality of nurses with monthly rotating night shifts. Subjects were enrolled at a medical center in central Taiwan with overall score ≥ 5 of Pittsburgh Sleep Quality Index (PSQI) and randomly assigned to the treatment or control groups. They were validated by pretests during their first graveyard shift in the trial period and the sleep quality information was collected by using the PSQI and sleep detectors. During the second graveyard shift, the treatment group received aromatherapy massage and the control group rested in the same aromatherapy room after work. All subjects filled out the PSQI surveys and the sleep quality information was collected during massage or resting and the following night. We found that the total PSQI was significantly decreased in the treatment group following the aromatherapy massage. Specifically, the components such as subjective sleep quality, sleep disturbance, and daytime dysfunction were significantly decreased. However, there were no significant changes of average PSQI scores between the two groups before and after intervention. Taken together, our study suggested that aromatherapy massage could improve sleep quality of nurses with monthly rotating night shift.

Rotation of an optically trapped vaterite microsphere measured using rotational Doppler effect

NASA Astrophysics Data System (ADS)

Chen, Xinlin; Xiao, Guangzong; Xiong, Wei; Yang, Kaiyong; Luo, Hui; Yao, Baoli

2018-03-01

The angular velocity of a vaterite microsphere spinning in the optical trap is measured using rotational Doppler effect. The perfectly spherical vaterite microspheres are synthesized via coprecipitation in the presence of silk fibroin nanospheres. When trapped by a circularly polarized beam, the vaterite microsphere is uniformly rotated in the trap center. The probe beams containing two Laguerre-Gaussian beams of opposite topological charge l = ± 7, l = ± 8, and l = ± 9 are illuminated on the spinning vaterite. By analyzing the backscattered light, a frequency shift is observed scaling with the rotation rate of the vaterite microsphere. The multiplicative enhancement of the frequency shift proportion to the topological charge has greatly improved the measurement precision. The reliability and practicability of this approach are verified through varying the topological charge of the probe beam and the trapping laser power. In consideration of the excellent measurement precision of the rotation frequency, this technique might be generally applicable in studying the torsional properties of micro-objects.

Productivity impact of headache on a heavy-manufacturing workforce in Turkey

PubMed Central

2013-01-01

Background Headache disorders cause substantial productivity losses through absenteeism and impaired effectiveness at work (presenteeism). We measured productivity losses from both causes at a heavy-manufacturing company with a largely male workforce in north-western Turkey. Methods We used the HALT Index as the survey instrument. We first assessed productivity losses by surveying the entire workforce. Because we anticipated much non-participation, we also applied HALT at the annual health-checks provided to all employees by the company’s on-site health clinic. Results Mean age of the workforce (N = 7,200) was 31 yr. About two thirds (90% male) were manual workers rotating weekly through early, late and night shifts. One third (50% male) were clerical/managerial, working a standard 5-day week. In the first assessment, 3,939 questionnaires (54.7%) were returned with usable data. In the previous 3 months, absenteeism of ≥1 day was reported by 360 respondents (9.1%), of whom 4 (0.10%) recorded ≥45 days (average per worker: 0.92 days/yr). Presenteeism equivalent to ≥1 day’s absence was reported by 1,187 respondents (29.4%) (average per worker: 6.0 days/yr). We estimated that 23,519 days/yr were lost in total among respondents (2.3% of workforce capacity). In the first 6 months of annual health-checks, 2,691 employees (37.4%) attended (94.4% male). Absenteeism was reported by 40 (1.5%), with 74 days lost, presenteeism by 348 (12.9%), with 1,240 days lost. We estimated that, altogether, 41,771 man-days/yr were lost in the entire workforce (2.4% of capacity; 94% due to presenteeism), closely matching the earlier estimate. A small minority (5.7%) of those with headache, who were only 2.5% of the workforce, accounted for >45% of presenteeism-related lost productivity. Conclusion The high productivity losses in a largely male workforce were surprising. Possible factors were the nature of the work – manual labour for two thirds, often heavy – and the recurring schedule disturbances of shift-work. There was a highly-disabled minority. PMID:24171915

76 FR 61748 - Mercer (US), Inc., a Subsidiary of Mercer LLC, a Subsidiary of Mercer, Inc., a Subsidiary of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-05

... that subject worker group separations were due to a shift to India and stated that other similar firms... for Reconsideration By application received July 22, 2011, a worker requested administrative reconsideration of the negative determination regarding workers' eligibility to apply for Trade Adjustment...

76 FR 61741 - Bmc Software, Inc. Including On-Site Leased Workers From COMSYS ITS Including Remote Workers...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-05

... employees provided various activities related to software development services. Based on these findings, the... workers of the subject firm who were adversely affected by a shift in software development services to a... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-74,540] Bmc Software, Inc...

Not-Knowing Gives Way to Knowing

ERIC Educational Resources Information Center

Anderson-Nathe, Ben

2008-01-01

One of the few truly reassuring features of not-knowing among youth workers is the realization that not-knowing cannot last forever. Eventually, some feature of the situation shifts, and youth workers move back into the capacity for action. This chapter describes the last of five themes associated with youth workers' experiences of not knowing…

Respirable Crystalline Silica Exposures During Asphalt Pavement Milling at Eleven Highway Construction Sites

PubMed Central

Hammond, Duane R.; Shulman, Stanley A.; Echt, Alan S.

2016-01-01

Asphalt pavement milling machines use a rotating cutter drum to remove the deteriorated road surface for recycling. The removal of the road surface has the potential to release respirable crystalline silica, to which workers can be exposed. This paper describes an evaluation of respirable crystalline silica exposures to the operator and ground worker from two different half-lane and larger asphalt pavement milling machines that had ventilation dust controls and water-sprays designed and installed by the manufacturers. Manufacturer A completed milling for eleven days at four highway construction sites in Wisconsin, while Manufacturer B completed milling for ten days at seven highway construction sites in Indiana. To evaluate the dust controls, full-shift personal breathing zone air samples were collected from an operator and ground worker during the course of normal employee work activities of asphalt pavement milling at eleven different sites. Forty-two personal breathing zone air samples were collected over 21 days (sampling on an operator and ground worker each day). All samples were below 50 µg/m3 for respirable crystalline silica, the National Institute for Occupational Safety and Health recommended exposure limit. The geometric mean personal breathing zone air sample was 6.2 µg/m3 for the operator and 6.1 µg/m3 for the ground worker for the Manufacturer A milling machine. The geometric mean personal breathing zone air sample was 4.2 µg/m3 for the operator and 9.0 µg/m3 for the ground worker for the Manufacturer B milling machine. In addition, upper 95% confidence limits for the mean exposure for each occupation were well below 50 µg/m3 for both studies. The silica content in the bulk asphalt material being milled ranged from 7% to 23% silica for roads milled by Manufacturer A and from 5% to 12% silica for roads milled by Manufacturer B. The results indicate that engineering controls consisting of ventilation controls in combination with water-sprays are capable of controlling occupational exposures to respirable crystalline silica generated by asphalt pavement milling machines on highway construction sites. PMID:26913983